Upgrade protolude to 0.3.1 (#2306 )

bump version to 9.0.1
* Format CHANGELOG
2022-06-08 16:15:56 -05:00 · 2022-06-03 22:19:16 -05:00 · 2022-06-03 22:19:16 -05:00 · 2022-06-03 22:19:16 -05:00 · 2022-06-03 22:19:16 -05:00 · 2022-06-03 22:19:16 -05:00
205 changed files with 7979 additions and 30085 deletions
@@ -1,9 +1,9 @@
 freebsd_instance:
-  image_family: freebsd-13-1
+  image_family: freebsd-13-0

 build_task:
  name: Build FreeBSD (Stack)
-  install_script: pkg install -y postgresql13-client hs-stack git
+  install_script: pkg install -y postgresql13-client hs-stack

  stack_cache:
    folders: /.stack
@@ -11,10 +11,8 @@ inputs:
 runs:
  using: composite
  steps:
-    - uses: cachix/install-nix-action@v23
-      with:
-        install_url: https://releases.nixos.org/nix/nix-2.13.3/install
-    - uses: cachix/cachix-action@v12
+    - uses: cachix/install-nix-action@v16
+    - uses: cachix/cachix-action@v10
      with:
        name: postgrest
        authToken: ${{ inputs.authToken }}
@@ -1,11 +1,6 @@
 version: 2
 updates:
-  - package-ecosystem: github-actions
-    directory: /
-    schedule:
-      interval: weekly
-
-  - package-ecosystem: github-actions
-    directory: /.github/actions/setup-nix
-    schedule:
-      interval: weekly
+- package-ecosystem: github-actions
+  directory: /
+  schedule:
+    interval: weekly
@@ -7,13 +7,12 @@ set -euo pipefail
 # https://docs.github.com/en/rest/reference/checks#list-check-suites-for-a-git-reference

 cirrus_artifact_name=bin
-gh_auth_header="Authorization: Bearer $GITHUB_TOKEN"
 gh_accept_header="Accept: application/vnd.github.v3+json"

 get_gh_check_runs_url() {
  gh_checks_list_url="https://api.github.com/repos/$GITHUB_REPOSITORY/commits/$GITHUB_COMMIT/check-suites"
  >&2 echo "Getting list of check-suites from $gh_checks_list_url ..."
-  curl --fail -H "$gh_auth_header" -H "$gh_accept_header"  "$gh_checks_list_url" \
+  curl --fail -H "$gh_accept_header"  "$gh_checks_list_url" \
    | jq -r '.check_suites[] | select(.app.slug == "cirrus-ci") | .check_runs_url'
 }

@@ -22,7 +21,7 @@ wait_for_cirrusci() {
  >&2 echo "Waiting to CirrusCI run to complete (two hours maximum)..."
  for _ in $(seq 1 120); do
    echo "Checking for CirrusCI task status at $gh_check_runs_url ..."
-    status=$(curl --fail -H "$gh_auth_header" "$gh_check_runs_url" | jq -r '.check_runs[] | .status')
+    status=$(curl --fail "$gh_check_runs_url" | jq -r '.check_runs[] | .status')
    if [ "$status" == "completed" ]; then
      break
    else
@@ -38,7 +37,7 @@ wait_for_cirrusci() {
 get_cirrus_taskid() {
  gh_check_runs_url="$(get_gh_check_runs_url)"
  >&2 echo "Getting the CirrusCI task id from $gh_check_runs_url ..."
-  curl --fail -H "$gh_auth_header" -H "$gh_accept_header" "$gh_check_runs_url" \
+  curl --fail -H "$gh_accept_header" "$gh_check_runs_url" \
    | jq -r '.check_runs[] | .external_id'
 }

@@ -4,15 +4,11 @@

 [ -z "$1" ] && { echo "Missing 1st argument: PostgREST github commit SHA"; exit 1; }
 [ -z "$2" ] && { echo "Missing 2nd argument: Build environment directory name"; exit 1; }
-[ -z "$3" ] && { echo "Missing 3rd argument: GHC version"; exit 1; }

 PGRST_GITHUB_COMMIT="$1"
 SCRIPT_DIR="$2"

 DOCKER_BUILD_DIR="$SCRIPT_DIR/docker-env"
-# latest is a shortcut documented on https://www.haskell.org/ghcup/guide/#tags-and-shortcuts
-CABAL_VERSION="latest"
-GHC_VERSION="$3"

 install_packages() {
  sudo apt-get update -y
@@ -30,14 +26,13 @@ install_ghcup() {

 install_cabal() {
  ghcup upgrade
-  ghcup install cabal $CABAL_VERSION
-  ghcup set cabal $CABAL_VERSION
+  ghcup install cabal 3.6.0.0
+  ghcup set cabal 3.6.0.0
 }

 install_ghc() {
-  ghcup upgrade
-  ghcup install ghc $GHC_VERSION
-  ghcup set ghc $GHC_VERSION
+  ghcup install ghc 8.10.7
+  ghcup set ghc 8.10.7
 }

 install_packages
@@ -46,8 +41,8 @@ install_packages
 [ -f ~/.ghcup/env ] && source ~/.ghcup/env

 ghcup --version || install_ghcup
-ghcup set cabal $CABAL_VERSION || install_cabal
-ghcup set ghc $GHC_VERSION || install_ghc
+cabal --version || install_cabal
+ghc --version || install_ghc

 cd ~/$SCRIPT_DIR

@@ -13,6 +13,4 @@ EXPOSE 3000

 USER 1000

-# Use the array form to avoid running the command using bash, which does not handle `SIGTERM` properly. 
-# See https://docs.docker.com/compose/faq/#why-do-my-services-take-10-seconds-to-recreate-or-stop 
-CMD ["postgrest"]
+CMD postgrest
@@ -1,78 +0,0 @@
-name: Cachix
-
-# This workflow serves to
-#   - keep cachix up to date with the main branch
-#   - incrementally update cachix for large dependency
-#     updates, e.g. after running postgrest-nixpkgs-upgrade,
-#     which can cause the main CI workflow to time out
-
-on:
-  workflow_dispatch:
-  push:
-    branches:
-      - main
-      - rel-*
-    tags:
-      - v*
-
-jobs:
-  Seed-Cachix:
-    strategy:
-      fail-fast: false
-      matrix:
-        include:
-          - os: Linux
-            runs-on: ubuntu-latest
-          - os: MacOS
-            runs-on: macos-latest
-    name: Seed ${{ matrix.os }}
-    runs-on: ${{ matrix.runs-on }}
-    steps:
-      - uses: actions/checkout@v4
-      - name: Setup Nix Environment
-        uses: ./.github/actions/setup-nix
-        with:
-          authToken: '${{ secrets.CACHIX_AUTH_TOKEN }}'
-
-      - name: Install cachix tooling
-        run: |
-          nix-env -f default.nix -iA devTools.pushCachix.bin
-          postgrest-push-cachix
-
-      - name: Seed dynamic postgrest build
-        run: |
-          nix-build -A postgrestPackage
-          postgrest-push-cachix
-
-      - name: Seed style tools
-        run: |
-          nix-build -A style
-          postgrest-push-cachix
-
-      - name: Seed test tools
-        run: |
-          nix-build -A tests
-          postgrest-push-cachix
-
-      - name: Seed static toolchain
-        if: matrix.os == 'Linux'
-        run: |
-          nix-build -A packagesStatic.haskellPackages.hello
-          postgrest-push-cachix
-
-      - name: Seed static postgresql build (for libpq)
-        if: matrix.os == 'Linux'
-        run: |
-          nix-build -A packagesStatic.pkgs.postgresql
-          postgrest-push-cachix
-
-      - name: Seed static postgrest build
-        if: matrix.os == 'Linux'
-        run: |
-          nix-build -A postgrestStatic
-          postgrest-push-cachix
-
-      - name: Build and push everything to Cachix
-        run: |
-          nix-build
-          postgrest-push-cachix
@@ -17,7 +17,7 @@ jobs:
    name: Lint & check code style
    runs-on: ubuntu-latest
    steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v3
      - name: Setup Nix Environment
        uses: ./.github/actions/setup-nix
        with:
@@ -37,16 +37,16 @@ jobs:
        # https://github.com/actions/runner/issues/241#issuecomment-842566950
        shell: script -qec "bash --noprofile --norc -eo pipefail {0}"
    steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v3
      - name: Setup Nix Environment
        uses: ./.github/actions/setup-nix
        with:
          tools: tests

-      - name: Run coverage (IO tests and Spec tests against PostgreSQL 15)
+      - name: Run coverage (IO tests and Spec tests against PostgreSQL 14)
        run: postgrest-coverage
      - name: Upload coverage to codecov
-        uses: codecov/codecov-action@v3.1.4
+        uses: codecov/codecov-action@v3.1.0
        with:
          files: ./coverage/codecov.json

@@ -63,7 +63,7 @@ jobs:
    strategy:
      fail-fast: false
      matrix:
-        pgVersion: [9.6, 10, 11, 12, 13, 14, 15, 16]
+        pgVersion: [9.6, 10, 11, 12, 13, 14]
    name: Test PG ${{ matrix.pgVersion }} (Nix)
    runs-on: ubuntu-latest
    defaults:
@@ -72,7 +72,7 @@ jobs:
        # https://github.com/actions/runner/issues/241#issuecomment-842566950
        shell: script -qec "bash --noprofile --norc -eo pipefail {0}"
    steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v3
      - name: Setup Nix Environment
        uses: ./.github/actions/setup-nix
        with:
@@ -84,14 +84,18 @@ jobs:

      - name: Run IO tests
        if: always()
-        run: postgrest-with-postgresql-${{ matrix.pgVersion }} -f test/io/fixtures.sql postgrest-test-io -vv
+        run: postgrest-with-postgresql-${{ matrix.pgVersion }} -f test/io/fixtures.sql postgrest-test-io
+
+      - name: Run query cost tests
+        if: always()
+        run: postgrest-with-postgresql-${{ matrix.pgVersion }} postgrest-test-querycost


  Test-Memory-Nix:
    name: Test memory (Nix)
    runs-on: ubuntu-latest
    steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v3
      - name: Setup Nix Environment
        uses: ./.github/actions/setup-nix
        with:
@@ -104,16 +108,14 @@ jobs:
    name: Build Linux static (Nix)
    runs-on: ubuntu-latest
    steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v3
      - name: Setup Nix Environment
        uses: ./.github/actions/setup-nix
        with:
-          tools: tests
+          authToken: '${{ secrets.CACHIX_AUTH_TOKEN }}'

      - name: Build static executable
        run: nix-build -A postgrestStatic
-      - name: Check static executable
-        run: postgrest-check-static result/bin/postgrest
      - name: Save built executable as artifact
        uses: actions/upload-artifact@v3
        with:
@@ -130,18 +132,12 @@ jobs:
          path: postgrest-docker.tar.gz
          if-no-files-found: error

-
-  Build-Macos-Nix:
-    name: Build MacOS (Nix)
-    runs-on: macos-latest
-    steps:
-      - uses: actions/checkout@v4
-      - name: Setup Nix Environment
-        uses: ./.github/actions/setup-nix
-
-      - name: Build everything
+      - name: Build and push everything to Cachix (main branch only)
+        if: ${{ github.ref == 'refs/heads/main' }}
        run: |
          nix-build
+          nix-env -f default.nix -iA devTools
+          postgrest-push-cachix


  Build-Stack:
@@ -149,18 +145,22 @@ jobs:
      fail-fast: false
      matrix:
        include:
-          - name: Linux
+          - name: Linux & test
            runs-on: ubuntu-latest
            cache: |
              ~/.stack
              .stack-work
+            test: true
+            pgdir: /usr/lib/postgresql
            artifact: postgrest-ubuntu-x64

-          - name: MacOS
+          - name: MacOS & test
            runs-on: macos-latest
            cache: |
              ~/.stack
              .stack-work
+            test: true
+            pgdir: /usr/local/Cellar/postgresql
            artifact: postgrest-macos-x64

          - name: Windows
@@ -170,12 +170,14 @@ jobs:
              ~\AppData\Local\Programs\stack
              .stack-work
            deps: Add-Content $env:GITHUB_PATH $env:PGBIN
+            # We'd need to make test/with_tmp_db run on Windows first
+            # test: true
            artifact: postgrest-windows-x64

    name: Build ${{ matrix.name }} (Stack)
    runs-on: ${{ matrix.runs-on }}
    steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v3
      - name: Stack working files cache
        uses: actions/cache@v3
        with:
@@ -186,6 +188,12 @@ jobs:
        run: ${{ matrix.deps }}
      - name: Build with Stack
        run: stack build --local-bin-path result --copy-bins
+      - name: Run Spec tests with Stack
+        if: ${{ matrix.test }}
+        run: |
+          postgresql_bin="$(find ${{ matrix.pgdir }} -maxdepth 2 -type d -name bin | head -n 1)"
+          echo "Using PostgreSQL binaries at $postgresql_bin ..."
+          PATH="$postgresql_bin:$PATH" test/with_tmp_db stack test
      - name: Save built executable as artifact
        uses: actions/upload-artifact@v3
        with:
@@ -199,12 +207,11 @@ jobs:
    name: Get FreeBSD build from CirrusCI
    runs-on: ubuntu-latest
    steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v3
      - name: Get FreeBSD executable from CirrusCI
        env:
          # GITHUB_SHA does weird things for pull request, so we roll our own:
-          GITHUB_COMMIT: ${{ github.event.pull_request.head.sha || github.sha }}
-          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          GITHUB_COMMIT: ${{github.event.pull_request.head.sha || github.sha}}
        run: .github/get_cirrusci_freebsd
      - name: Save executable as artifact
        uses: actions/upload-artifact@v3
@@ -213,57 +220,19 @@ jobs:
          path: postgrest
          if-no-files-found: error

-  Build-Cabal:
-    strategy:
-      matrix:
-        ghc: ['9.0.2', '9.2.4']
-      fail-fast: false
-    name: Build Linux (Cabal, GHC ${{ matrix.ghc }})
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v4
-      - name: Workaround runner image issue
-        # https://github.com/actions/runner-images/issues/7061
-        run: sudo chown -R "$USER" /usr/local/.ghcup
-      - name: ghcup
-        run: |
-          ghcup install ghc ${{ matrix.ghc }}
-          ghcup set ghc ${{ matrix.ghc }}
-      - name: Copy cabal.project
-        run: |
-          cp cabal.project.non-nix cabal.project
-      - name: Cache
-        uses: actions/cache@v3
-        with:
-          path: ~/.cabal
-          key: ${{ runner.os }}-${{ matrix.ghc }}-${{ hashFiles('**/*.cabal') }}-${{ hashFiles('**/cabal.project') }}
-          restore-keys: |
-            ${{ runner.os }}-${{ matrix.ghc }}-
-      - name: Install dependencies
-        run: |
-          cabal update
-          cabal build --only-dependencies --enable-tests --enable-benchmarks
-      - name: Build
-        run: cabal build --enable-tests --enable-benchmarks all
-
  Build-Cabal-Arm:
-    strategy:
-      matrix:
-        ghc: ['9.2.4']
-      fail-fast: false
-    name: Build aarch64 (Cabal, GHC ${{ matrix.ghc }})
+    name: Build aarch64 (Cabal)
    if: ${{ github.ref == 'refs/heads/main' || startsWith(github.ref, 'refs/tags/v') || startsWith(github.ref, 'refs/heads/rel-') }}
    runs-on: ubuntu-latest
    outputs:
      remotepath: ${{ steps.Remote-Dir.outputs.remotepath }}
    env:
      GITHUB_COMMIT: ${{ github.sha }}
-      GHC_VERSION: ${{ matrix.ghc }}
    steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v2.4.0
      - id: Remote-Dir
        name: Unique directory name for the remote build
-        run: echo "remotepath=postgrest-build-$(uuidgen)" >> "$GITHUB_OUTPUT"
+        run: echo "::set-output name=remotepath::postgrest-build-$(uuidgen)"
      - name: Copy script files to the remote server
        uses: appleboy/scp-action@master
        with:
@@ -285,8 +254,8 @@ jobs:
          fingerprint: ${{ secrets.SSH_ARM_FINGERPRINT }}
          command_timeout: 120m
          script_stop: true
-          envs: GITHUB_COMMIT,REMOTE_DIR,GHC_VERSION
-          script: bash ~/$REMOTE_DIR/build.sh "$GITHUB_COMMIT" "$REMOTE_DIR" "GHC_VERSION"
+          envs: GITHUB_COMMIT,REMOTE_DIR
+          script: bash ~/$REMOTE_DIR/build.sh "$GITHUB_COMMIT" "$REMOTE_DIR"
      - name: Download binaries from remote server
        uses: nicklasfrahm/scp-action@main
        with:
@@ -300,7 +269,7 @@ jobs:
      - name: Extract downloaded binaries
        run: tar -xvf result.tar.xz && rm result.tar.xz
      - name: Save aarch64 executable as artifact
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v2.3.1
        with:
          name: postgrest-ubuntu-aarch64
          path: result/postgrest
@@ -324,7 +293,7 @@ jobs:
      version: ${{ steps.Identify-Version.outputs.version }}
      isprerelease: ${{ steps.Identify-Version.outputs.isprerelease }}
    steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v3
      - id: Identify-Version
        name: Identify the version to be released
        run: |
@@ -336,14 +305,14 @@ jobs:
            exit 1
          else
            echo "Version to be released is $cabal_version"
-            echo "version=$cabal_version" >> "$GITHUB_OUTPUT"
+            echo "::set-output name=version::$cabal_version"
          fi

          if [[ "$cabal_version" != *.*.*.* ]]; then
            echo "Version is for a full release (version does not have four components)"
          else
            echo "Version is for a pre-release (version has four components, e.g., 1.1.1.1)"
-            echo "isprerelease=1" >> "$GITHUB_OUTPUT"
+            echo "::set-output name=isprerelease::1"
          fi
      - name: Identify changes from CHANGELOG.md
        run: |
@@ -377,7 +346,7 @@ jobs:
    env:
      VERSION: ${{ needs.Prepare-Release.outputs.version }}
    steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v3
      - name: Download all artifacts
        uses: actions/download-artifact@v3
        with:
@@ -434,6 +403,7 @@ jobs:
    name: Release on Docker Hub
    runs-on: ubuntu-latest
    needs:
+      - Build-Cabal-Arm
      - Prepare-Release
    env:
      GITHUB_COMMIT: ${{ github.sha }}
@@ -443,7 +413,7 @@ jobs:
      VERSION: ${{ needs.Prepare-Release.outputs.version }}
      ISPRERELEASE: ${{ needs.Prepare-Release.outputs.isprerelease }}
    steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v3
      - name: Setup Nix Environment
        uses: ./.github/actions/setup-nix
        with:
@@ -468,6 +438,18 @@ jobs:
          else
            echo "Skipping pushing to 'latest' tag for v$VERSION pre-release..."
          fi
+      - name: Publish images for ARM builds on Docker Hub
+        uses: appleboy/ssh-action@master
+        env:
+          REMOTE_DIR: ${{ needs.Build-Cabal-Arm.outputs.remotepath }}
+        with:
+          host: ${{ secrets.SSH_ARM_HOST }}
+          username: ubuntu
+          key: ${{ secrets.SSH_ARM_PRIVATE_KEY }}
+          fingerprint: ${{ secrets.SSH_ARM_FINGERPRINT }}
+          script_stop: true
+          envs: GITHUB_COMMIT,DOCKER_REPO,DOCKER_USER,DOCKER_PASS,REMOTE_DIR,VERSION,ISPRERELEASE
+          script: bash ~/$REMOTE_DIR/docker-publish.sh "$GITHUB_COMMIT" "$DOCKER_REPO" "$DOCKER_USER" "$DOCKER_PASS" "$REMOTE_DIR" "$VERSION" "$ISPRERELEASE"
 # TODO: Enable dockerhub description update again, once a solution for the permission problem is found:
 # https://github.com/docker/hub-feedback/issues/1927
 #      - name: Update descriptions on Docker Hub
@@ -481,49 +463,17 @@ jobs:
 #            echo "Skipping updating description for pre-release..."
 #          fi

-  Release-Docker-Arm:
-    name: Release Arm Builds on Docker Hub
-    runs-on: ubuntu-latest
-    needs:
-      - Build-Cabal-Arm
-      - Prepare-Release
-      - Release-Docker
-    env:
-      GITHUB_COMMIT: ${{ github.sha }}
-      DOCKER_REPO: postgrest
-      DOCKER_USER: stevechavez
-      DOCKER_PASS: ${{ secrets.DOCKER_PASS }}
-      VERSION: ${{ needs.Prepare-Release.outputs.version }}
-      ISPRERELEASE: ${{ needs.Prepare-Release.outputs.isprerelease }}
-    steps:
-      - uses: actions/checkout@v4
-      - name: Publish images for ARM builds on Docker Hub
-        uses: appleboy/ssh-action@master
-        env:
-          REMOTE_DIR: ${{ needs.Build-Cabal-Arm.outputs.remotepath }}
-        with:
-          host: ${{ secrets.SSH_ARM_HOST }}
-          username: ubuntu
-          key: ${{ secrets.SSH_ARM_PRIVATE_KEY }}
-          fingerprint: ${{ secrets.SSH_ARM_FINGERPRINT }}
-          script_stop: true
-          envs: GITHUB_COMMIT,DOCKER_REPO,DOCKER_USER,DOCKER_PASS,REMOTE_DIR,VERSION,ISPRERELEASE
-          script: bash ~/$REMOTE_DIR/docker-publish.sh "$GITHUB_COMMIT" "$DOCKER_REPO" "$DOCKER_USER" "$DOCKER_PASS" "$REMOTE_DIR" "$VERSION" "$ISPRERELEASE"
-
  Clean-Arm-Server:
    name: Remove copied files from server
    needs:
      - Build-Cabal-Arm
-      - Release-Docker-Arm
-    if: success() ||
-      needs.Build-Cabal-Arm.result == 'failure' ||
-      needs.Build-Cabal-Arm.result == 'cancelled' ||
-      (needs.Build-Cabal-Arm.result == 'success' && !startsWith(github.ref, 'refs/tags/v'))
+      - Release-Docker
+    if: ${{ always() && (github.ref == 'refs/heads/main' || startsWith(github.ref, 'refs/tags/v') || startsWith(github.ref, 'refs/heads/rel-')) }}
    runs-on: ubuntu-latest
    env:
      REMOTE_DIR: ${{ needs.Build-Cabal-Arm.outputs.remotepath }}
    steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v2.4.0
      - name: Remove uploaded files from server
        uses: appleboy/ssh-action@master
        with:
@@ -15,7 +15,7 @@ jobs:
    name: Loadtest (Nix)
    runs-on: ubuntu-latest
    steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v3
        with:
          fetch-depth: 0
      - name: Setup Nix Environment
@@ -22,7 +22,7 @@ jobs:
          name: loadtest.md
          path: artifacts
      - name: Upload to GitHub Checks
-        uses: LouisBrunner/checks-action@v1.6.2
+        uses: LouisBrunner/checks-action@v1.2.0
        with:
          token: ${{ secrets.GITHUB_TOKEN }}
          sha: ${{ github.event.workflow_run.head_sha }}
@@ -22,4 +22,3 @@ __pycache__
 coverage
 .hpc
 loadtest
-.history
@@ -1,68 +0,0 @@
-# Architecture
-
-This document describes the high-level architecture of PostgREST.
-
-## Bird's Eye View
-
-```haskell
-postgrest :: Request -> Either Error SQLStatement -> Response
-```
-
-On the highest level, PostgREST processes an HTTP request, if it's accepted it builds a SQL statement for it, executes it, and produces a response.
-
-## Code Map
-
-This section talks briefly about various important modules.
-
-The starting point of the program is `main/Main.hs`, which calls `src/PostgREST/CLI.hs` which then calls `src/PostgREST/App.hs`.
-
-`App.hs` is then in charge of composing the different modules.
-
-### ApiRequest.hs
-
-PostgREST operates over two types of resources: database relations(tables or views) and database functions; providing different representations(depending on the media type)
-for them.
-
-This module is in charge of representing the operation over an `ApiRequest` type. It parses the URL querystring following PostgREST syntax, the request headers, and the request body
-(if possible it avoids parsing the body and sends it directly to the db).
-
-A request might be rejected at this level if it's invalid, e.g. providing an unknown media type to PostgREST or using an unknown HTTP method.
-
-### Plan.hs
-
-Using the Schema Cache, this module enables more complex functionality(like resource embedding) by enriching the ApiRequest. It generates Plan types(`ReadPlan`, `MutatePlan`)
-that then will be used to generate a SQL statement.
-
-A request might be rejected at this level if it's invalid, e.g. by doing resource embedding on a nonexistent resource.
-
-An OPTIONS request doesn't require a plan to be generated.
-
-### Query.hs
-
-This module constructs single SQL statements that can be parametrized and prepared. Only at this stage a PostgreSQL connection from the pool is used.
-
-A query might fail(and be rollbacked) at this level if it doesn't comply to certain conditions, e.g. by not returning a single row when a ``Accept: application/vnd.pgrst.object`` header is specified.
-
-An OPTIONS request doesn't require a query to be executed.
-
-### Response.hs
-
-This module constructs the HTTP response body with the right headers.
-
-It builds the OpenAPI response using the schema cache.
-
-### Auth.hs
-
-This module provides functions to deal with JWT authorization.
-
-### SchemaCache.hs
-
-This queries the PostgreSQL system catalogs and caches the metadata into a SchemaCache type,
-
-### AppState.hs
-
-The state of the App which is kept across requests.
-
-This spawns threads which are used to execute concurrent jobs.
-
-Jobs include connection recover and a listener for the PostgreSQL LISTEN command.
@@ -46,14 +46,12 @@ PostgREST ongoing development is only possible thanks to our Sponsors and Backer

 ## Lead Backers

- [Roboflow](https://github.com/roboflow)
 - Evans Fernandes
 - [Jan Sommer](https://github.com/nerfpops)
 - [Franz Gusenbauer](https://www.igutech.at/)

 ## Backers

- Zac Miller
 - Tsingson Qin
 - Michel Pelletier
 - Jay Hannah
@@ -3,330 +3,25 @@
 All notable changes to this project will be documented in this file.
 This project adheres to [Semantic Versioning](http://semver.org/).

-## Unreleased
-
-## [11.2.2] - 2023-10-25
-
-### Fixed
-
- - #2824, Fix regression by reverting fix that returned 206 when first position = length in a `Range` header - @laurenceisla, @strengthless
-
-## [11.2.1] - 2023-10-03
-
-### Fixed
-
- - #2899, Fix `application/vnd.pgrst.array` not accepted as a valid mediatype - @taimoorzaeem
- - #2524, Fix schema cache and configuration reloading with `NOTIFY` not working on Windows - @diogob, @laurenceisla
- - #2915, Fix duplicate headers in response - @taimoorzaeem
- - #2824, Fix range request with first position same as length return status 206 - @taimoorzaeem
- - #2939, Fix wrong `Preference-Applied` with `Prefer: tx=commit` when transaction is rollbacked - @steve-chavez
- - #2939, Fix `count=exact` not being included in `Preference-Applied` - @steve-chavez
- - #2800, Fix not including to-one embed resources that had a `NULL` value in any of the selected fields when doing null filtering on them - @laurenceisla
- - #2846, Fix error when requesting `Prefer: count=<type>` and doing null filtering on embedded resources - @laurenceisla
- - #2959, Fix setting `default_transaction_isolation` unnecessarily - @steve-chavez
- - #2929, Fix arrow filtering on RPC returning dynamic TABLE with composite type - @steve-chavez
- - #2963, Fix RPCs not embedding correctly when using overloaded functions for computed relationships - @laurenceisla
- - #2970, Fix regression that rejects URI connection strings with certain unescaped characters in the password - @laurenceisla, @steve-chavez
-
-## [11.2.0] - 2023-08-10
-
-### Added
-
- - #2523, Data representations - @aljungberg
-   + Allows for flexible API output formatting and input parsing on a per-column type basis using regular SQL functions configured in the database
-   + Enables greater flexibility in the form and shape of your APIs, both for output and input, making PostgREST a more versatile general-purpose API server
-   + Examples include base64 encode/decode your binary data (like a `bytea` column containing an image), choose whether to present a timestamp column as seconds since the Unix epoch or as an ISO 8601 string, or represent fixed precision decimals as strings, not doubles, to preserve precision
-   + ...and accept the same in `POST/PUT/PATCH` by configuring the reverse transformation(s)
-   + Other use-cases include custom representation of enums, arrays, nested objects, CSS hex colour strings, gzip compressed fields, metric to imperial conversions, and much more
-   + Works when using the `select` parameter to select only a subset of columns, embedding through complex joins, renaming fields, with views and computed columns
-   + Works when filtering on a formatted column without extra indexes by parsing to the canonical representation
-   + Works for data `RETURNING` operations, such as requesting the full body in a POST/PUT/PATCH with `Prefer: return=representation`
-   + Works for batch updates and inserts
-   + Completely optional, define the functions in the database and they will be used automatically everywhere
-   + Data representations preserve the ability to write to the original column and require no extra storage or complex triggers (compared to using `GENERATED ALWAYS` columns)
-   + Note: data representations require Postgres 10 (Postgres 11 if using `IN` predicates); data representations are not implemented for RPC
- - #2647, Allow to verify the PostgREST version in SQL: `select distinct application_name from pg_stat_activity`. - @laurenceisla
- - #2856, Add the `--version` CLI option that prints the version information - @laurenceisla
- - #1655, Improve `details` field of the singular error response - @taimoorzaeem
- - #740, Add `Preference-Applied` in response for `Prefer: return=representation/headers-only/minimal` - @taimoorzaeem
- - #1601, Add optional `nulls=stripped` parameter for mediatypes `application/vnd.pgrst.array+json` and `application/vnd.pgrst.object+json` - @taimoorzaeem
-
-### Fixed
-
- - #2821, Fix OPTIONS not accepting all available media types - @steve-chavez
- - #2834, Fix compilation on Ubuntu by being compatible with GHC 9.0.2 - @steve-chavez
- - #2840, Fix `Prefer: missing=default` with DOMAIN default values - @steve-chavez
- - #2849, Fix HEAD unnecessarily executing aggregates - @steve-chavez
- - #2594, Fix unused index on jsonb/jsonb arrow filter and order (``/bets?data->>contractId=eq.1`` and ``/bets?order=data->>contractId``) - @steve-chavez
- - #2861, Fix character and bit columns with fixed length not inserting/updating properly - @laurenceisla
-   + Fixes the error "value too long for type character(1)" when the char length of the column was bigger than one.
- - #2862, Fix null filtering on embedded resource when using a column name equal to the relation name - @steve-chavez
- - #1586, Fix function parameters of type character and bit not ignoring length - @laurenceisla
-   + Fixes the error "value too long for type character(1)" when the char length of the parameter was bigger than one.
- - #2881, Fix error when a function returns `RECORD` or `SET OF RECORD` - @laurenceisla
- - #2896, Fix applying superuser settings for impersonated role - @steve-chavez
-
-### Deprecated
-
- - #2863, Deprecate resource embedding target disambiguation - @steve-chavez
-   + The `/table?select=*,other!fk(*)` must be used to disambiguate
-   + The server aids in choosing the `!fk` by sending a `hint` on the error whenever an ambiguous request happens.
-
-## [11.1.0] - 2023-06-07
-
-### Added
-
- - #2786, Limit idle postgresql connection lifetime - @robx
-   + New option `db-pool-max-idletime` (default 30s).
-   + This is equivalent to the old option `db-pool-timeout` of PostgREST 10.0.0.
-   + A config alias for `db-pool-timeout` is included.
- - #2703, Add pre-config function - @steve-chavez
-    + New config option `db-pre-config`(empty by default)
-    + Allows using the in-database configuration without SUPERUSER
- - #2781, When `db-channel-enabled` is false, start automatic connection recovery on a new request when pool connections are closed with `pg_terminate_backend` - @steve-chavez
-    + Mitigates the lack of LISTEN/NOTIFY for schema cache reloading on read replicas.
-
-### Fixed
-
- - #2791, Fix dropping schema cache reload notifications  - @steve-chavez
- - #2801, Stop retrying connection when "no password supplied" - @steve-chavez
-
-## [11.0.1] - 2023-04-27
-
-### Fixed
-
- - #2762, Fixes "permission denied for schema" error during schema cache load - @steve-chavez
- - #2756, Fix bad error message on generated columns when using `Prefer: missing=default` - @steve-chavez
- - #1139, Allow a 30 second skew for JWT validation - @steve-chavez
-   + It used to be 1 second, which was too strict
-
-## [11.0.0] - 2023-04-16
-
-### Added
-
- - #1414, Add related orders - @steve-chavez
-   + On a many-to-one or one-to-one relationship, you can order a parent by a child column `/projects?select=*,clients(*)&order=clients(name).desc.nullsfirst`
- - #1233, #1907, #2566, Allow spreading embedded resources - @steve-chavez
-   + On a many-to-one or one-to-one relationship, you can unnest a json object with `/projects?select=*,...clients(client_name:name)`
-   + Allows including the join table columns when resource embedding
-   + Allows disambiguating a recursive m2m embed
-   + Allows disambiguating an embed that has a many-to-many relationship using two foreign keys on a junction
- - #2340, Allow embedding without selecting any column - @steve-chavez
- - #2563, Allow `is.null` or `not.is.null` on an embedded resource - @steve-chavez
-   + Offers a more flexible replacement for `!inner`, e.g. `/projects?select=*,clients(*)&clients=not.is.null`
-   + Allows doing an anti join, e.g. `/projects?select=*,clients(*)&clients=is.null`
-   + Allows using or across related tables conditions
- - #1100, Customizable OpenAPI title - @AnthonyFisi
- - #2506, Add `server-trace-header` for tracing HTTP requests.  - @steve-chavez
-   + When the client sends the request header specified in the config it will be included in the response headers.
- - #2694, Make `db-root-spec` stable. - @steve-chavez
-   + This can be used to override the OpenAPI spec with a custom database function
- - #1567, On bulk inserts, missing values can get the column DEFAULT by using the `Prefer: missing=default` header - @steve-chavez
- - #2501, Allow filtering by`IS DISTINCT FROM` using the `isdistinct` operator, e.g. `/people?alias=isdistinct.foo`
- - #1569, Allow `any/all` modifiers on the `eq,like,ilike,gt,gte,lt,lte,match,imatch` operators, e.g. `/tbl?id=eq(any).{1,2,3}` - @steve-chavez
-   - This converts the input into an array type
- - #2561, Configurable role settings - @steve-chavez
-   - Database roles that are members of the connection role get their settings applied, e.g. doing
-     `ALTER ROLE anon SET statement_timeout TO '5s'` will result in that `statement_timeout` getting applied for that role.
-   - Works when switching roles when a JWT is sent
-   - Settings can be reloaded with `NOTIFY pgrst, 'reload config'`.
- - #2468, Configurable transaction isolation level with `default_transaction_isolation` - @steve-chavez
-   - Can be set per function `create function .. set default_transaction_isolation = 'repeatable read'`
-   - Or per role `alter role .. set default_transaction_isolation = 'serializable'`
-
-### Fixed
-
- - #2651, Add the missing `get` path item for RPCs to the OpenAPI output - @laurenceisla
- - #2648, Fix inaccurate error codes with new ones - @laurenceisla
-   + `PGRST204`: Column is not found
-   + `PGRST003`: Timed out when acquiring connection to db
- - #1652, Fix function call with arguments not inlining - @steve-chavez
- - #2705, Fix bug when using the `Range` header on `PATCH/DELETE` - @laurenceisla
-   + Fix the`"message": "syntax error at or near \"RETURNING\""` error
-   + Fix doing a limited update/delete when an `order` query parameter was present
- - #2742, Fix db settings and pg version queries not getting prepared  - @steve-chavez
- - #2618, Fix `PATCH` requests not recognizing embedded filters and using the top-level resource instead - @steve-chavez
-
-### Changed
-
- - #2705, The `Range` header is now only considered on `GET` requests and is ignored for any other method - @laurenceisla
-   + Other methods should use the `limit/offset` query parameters for sub-ranges
-   + `PUT` requests no longer return an error when this header is present (using `limit/offset` still triggers the error)
- - #2733, Remove bulk RPC call with the `Prefer: params=multiple-objects` header. A function with a JSON array or object parameter should be used instead.
-
-## [10.2.0] - 2023-04-12
-
-### Added
-
- - #2663, Limit maximal postgresql connection lifetime - @robx
-   + New option `db-pool-max-lifetime` (default 30m)
-   + `db-pool-acquisition-timeout` is no longer optional and defaults to 10s
-   + Fixes postgresql resource leak with long-lived connections (#2638)
-
-### Fixed
-
- - #2667, Fix `db-pool-acquisition-timeout` not logging to stderr when the timeout is reached - @steve-chavez
-
-## [10.1.2] - 2023-02-01
-
-### Fixed
-
- - #2565, Fix bad M2M embedding on RPC - @steve-chavez
- - #2575, Replace misleading error message when no function is found with a hint containing functions/parameters names suggestions - @laurenceisla
- - #2582, Move explanation about "single parameters" from the `message` to the `details` in the error output - @laurenceisla
- - #2569, Replace misleading error message when no relationship is found with a hint containing parent/child names suggestions - @laurenceisla
- - #1405, Add the required OpenAPI items object when the parameter is an array - @laurenceisla
- - #2592, Add upsert headers for POST requests to the OpenAPI output - @laurenceisla
- - #2623, Fix FK pointing to VIEW instead of TABLE in OpenAPI output - @laurenceisla
- - #2622, Consider any PostgreSQL authentication failure as fatal and exit immediately - @michivi
- - #2620, Fix `NOTIFY pgrst` not reloading the db connections catalog cache - @steve-chavez
-
-## [10.1.1] - 2022-11-08
-
-### Fixed
-
- - #2548, Fix regression when embedding views with partial references to multi column FKs - @wolfgangwalther
- - #2558, Fix regression when requesting limit=0 and `db-max-row` is set - @laurenceisla
- - #2542, Return a clear error without hitting the database when trying to update or insert an unknown column with `?columns` - @aljungberg
-
-## [10.1.0] - 2022-10-28
-
-### Added
-
- - #2348, Add `db-pool-acquisition-timeout` configuration option, time in seconds to wait to acquire a connection. - @robx
-
-### Fixed
-
- - #2261, #2349, #2467, Reduce allocations communication with PostgreSQL, particularly for request bodies. - @robx
- - #2401, #2444, Fix SIGUSR1 to fully flush connections pool. - @robx
- - #2428, Fix opening an empty transaction on failed resource embedding - @steve-chavez
- - #2455, Fix embedding the same table multiple times - @steve-chavez
- - #2518, Fix a regression when embedding views where base tables have a different column order for FK columns - @wolfgangwalther
- - #2458, Fix a regression with the location header when inserting into views with PKs from multiple tables - @wolfgangwalther
- - #2356, Fix a regression in openapi output with mode follow-privileges - @wolfgangwalther
- - #2283, Fix infinite recursion when loading schema cache with self-referencing view - @wolfgangwalther
- - #2343, Return status code 200 for PATCH requests which don't affect any rows - @wolfgangwalther
- - #2481, Treat computed relationships not marked SETOF as M2O/O2O relationship - @wolfgangwalther
- - #2534, Fix embedding a computed relationship with a normal relationship - @steve-chavez
- - #2362, Fix error message when [] is used inside select - @wolfgangwalther
- - #2475, Disallow !inner on computed columns - @wolfgangwalther
- - #2285, Ignore leading and trailing spaces in column names when parsing the query string - @wolfgangwalther
- - #2545, Fix UPSERT with PostgreSQL 15 - @wolfgangwalther
- - #2459, Fix embedding views with multiple references to the same base column - @wolfgangwalther
-
-### Changed
-
- - #2444, Removed `db-pool-timeout` option, because this was removed upstream in hasql-pool. - @robx
- - #2343, PATCH requests that don't affect any rows no longer return 404 - @wolfgangwalther
- - #2537, Stricter parsing of query string. Instead of silently ignoring, the parser now throws on invalid syntax like json paths for embeddings, hints for regular columns, empty casts or fts languages, etc. - @wolfgangwalther
-
-### Deprecated
-
- - #1385, Deprecate bulk-calls when including the `Prefer: params=multiple-objects` in the request. A function with a JSON array or object parameter should be used instead for a better performance.
-
-## [10.0.0] - 2022-08-18
-
-### Added
-
- - #1933, #2109, Add a minimal health check endpoint - @steve-chavez
-   + For enabling this, the `admin-server-port` config must be set explictly
-   + A `<host>:<admin_server_port>/live` endpoint is available for checking if postgrest is running on its port/socket. 200 OK = alive, 503 = dead.
-   + A `<host>:<admin_server_port>/ready` endpoint is available for checking a correct internal state(the database connection plus the schema cache). 200 OK = ready, 503 = not ready.
- - #1988, Add the current user to the request log on stdout - @DavidLindbom, @wolfgangwalther
- - #1823, Add the ability to run postgrest without any configuration. - @wolfgangwalther
-   + #1991, Add the ability to run without `db-uri` using libpq's PG environment variables to connect. - @wolfgangwalther
-   + #1769, Add the ability to run without `db-schemas`, defaulting to `db-schemas=public`. - @wolfgangwalther
-   + #1689, Add the ability to run without `db-anon-role` disabling anonymous access. - @wolfgangwalther
- - #1543, Allow access to fields of composite types in select=, order= and filters through JSON operators -> and ->>. - @wolfgangwalther
- - #2075, Allow access to array items in ?select=, ?order= and filters through JSON operators -> and ->>. - @wolfgangwalther
- - #2156, #2211, Allow applying `limit/offset` to UPDATE/DELETE to only affect a subset of rows - @steve-chavez
-   + It requires an explicit `order` on a unique column(s)
- - #1917, Add error codes with the `"PGRST"` prefix to the error response body to differentiate PostgREST errors from PostgreSQL errors - @laurenceisla
- - #1917, Normalize the error response body by always having the `detail` and `hint` error fields with a `null` value if they are empty - @laurenceisla
- - #2176, Errors raised with `SQLSTATE` now include the message and the code in the response body - @laurenceisla
- - #2236, Support POSIX regular expression operators for row filtering - @enote-kane
- - #2202, Allow returning XML from RPCs - @fjf2002
- - #2268, Allow returning XML from single-column queries - @fjf2002
- - #2300, RPC POST for function w/single unnamed XML param #2300 - @fjf2002
- - #1564, Allow geojson output by specifying the `Accept: application/geo+json` media type - @steve-chavez
-   + Requires postgis >= 3.0
-   + Works for GET, RPC, POST/PATCH/DELETE with `Prefer: return=representation`.
-   + Resource embedding works and the embedded rows will go into the `properties` key
-   + In case of multiple geometries in the same table, you can choose which one will go into the `geometry` key with the usual `?select` query parameter.
- - #1082, Add security definitions to the OpenAPI output - @laurenceisla
- - #2378, Support http OPTIONS method on RPC and root path - @steve-chavez
- - #2354, Allow getting the EXPLAIN plan of a request by using the `Accept: application/vnd.pgrst.plan` header - @steve-chavez
-   + Only allowed if the `db-plan-enabled` config is set to true
-   + Can generate the plan for different media types using the `for` parameter: `Accept: application/vnd.pgrst.plan; for="application/vnd.pgrst.object"`
-   + Different options for the plan can be used with the `options` parameter: `Accept: application/vnd.pgrst.plan; options=analyze|verbose|settings|buffers|wal`
-   + The plan can be obtained in text or json by using different media type suffixes: `Accept: application/vnd.pgrst.plan+text` and `Accept: application/vnd.pgrst.plan+json`.
- - #2144, Support computed relationships which allow extending and overriding relationships for resource embedding - @steve-chavez, @wolfgangwalther
- - #1984, Detect one-to-one relationships for resource embedding - @steve-chavez
-   + Detected when there's a foreign key with a unique constraint or when a foreign key is also a primary key
-
-### Fixed
-
- - #2058, Return 204 No Content without Content-Type for PUT - @wolfgangwalther
- - #2107, Clarify error for failed schema cache load. - @steve-chavez
-   + From `Database connection lost. Retrying the connection` to `Could not query the database for the schema cache. Retrying.`
- - #1771, Fix silently ignoring filter on a non-existent embedded resource - @steve-chavez
- - #2152, Remove functions, which are uncallable because of unnamend arguments from schema cache and OpenAPI output. - @wolfgangwalther
- - #2145, Fix accessing json array fields with -> and ->> in ?select= and ?order=. - @wolfgangwalther
- - #2155, Ignore `max-rows` on POST, PATCH, PUT and DELETE - @steve-chavez
- - #2254, Fix inferring a foreign key column as a primary key column on views - @steve-chavez
- - #2070, Restrict generated many-to-many relationships - @steve-chavez
-   + Only adds many-to-many relationships when: a table has FKs to two other tables and these FK columns are part of the table's PK columns.
- - #2278, Allow casting to types with underscores and numbers(e.g. `select=oid_array::_int4`) - @steve-chavez
- - #2277, #2238, #1643, Prevent views from breaking one-to-many/many-to-one embeds when using column or FK as target - @steve-chavez
-    + When using a column or FK as target for embedding(`/tbl?select=*,col-or-fk(*)`), only tables are now detected and views are not.
-    + You can still use a column or an inferred FK on a view to embed a table(`/view?select=*,col-or-fk(*)`)
- - #2317, Increase the `db-pool-timeout` to 1 hour to prevent frequent high connection latency - @steve-chavez
- - #2341, The search path now correctly identifies schemas with uppercase and special characters in their names (regression) - @laurenceisla
- - #2364, "404 Not Found" on nested routes and "405 Method Not Allowed" errors no longer start an empty database transaction - @steve-chavez
- - #2342, Fix inaccurate result count when an inner embed was selected after a normal embed in the query string - @laurenceisla
- - #2376, OPTIONS requests no longer start an empty database transaction - @steve-chavez
- - #2395, Allow using columns with dollar sign($) without double quoting in filters and `select` - @steve-chavez
- - #2410, Fix loop crash error on startup in Postgres 15 beta 3. Log: "UNION types \"char\" and text cannot be matched". - @yevon
- - #2397, Fix race conditions managing database connection helper - @robx
- - #2269, Allow `limit=0` in the request query to return an empty array - @gautam1168, @laurenceisla
- - #2401, Ensure database connections can't outlive SIGUSR1 - @robx
-
-### Changed
-
- - #2001, Return 204 No Content without Content-Type for RPCs returning VOID - @wolfgangwalther
-   + Previously, those RPCs would return "null" as a body with Content-Type: application/json.
- - #2156, `limit/offset` now limits the affected rows on UPDATE/DELETE  - @steve-chavez
-   + Previously, `limit/offset` only limited the returned rows but not the actual updated rows
- - #2155, `max-rows` is no longer applied on POST/PATCH/PUT/DELETE returned rows - @steve-chavez
-   + This was misleading because the affected rows were not really affected by `max-rows`, only the returned rows were limited
- - #2070, Restrict generated many-to-many relationships - @steve-chavez
-   + A primary key that contains the foreign key columns is now needed for generating many-to-many relationships.
- - #2277, Views now are not detected when embedding using the column or FK as target (`/view?select=*,column(*)`) - @steve-chavez
-   + This embedding form was easily made ambiguous whenever a new view was added.
-   + You can use computed relationships to keep this embedding form working
- - #2312, Using `Prefer: return=representation` no longer returns a `Location` header - @laurenceisla
- - #1984, For the cases where one to one relationships are detected, json objects will be returned instead of json arrays of length 1
-   + If you wish to override this behavior, you can use computed relationships to return arrays again
-
 ## [9.0.1] - 2022-06-03

 ### Fixed

- #2165, Fix json/jsonb columns should not have type in OpenAPI spec - @clrnd
- #2020, Execute deferred constraint triggers when using `Prefer: tx=rollback` - @wolfgangwalther
- #2077, Fix `is` not working with upper or mixed case values like `NULL, TrUe, FaLsE` - @steve-chavez
- #2024, Fix schema cache loading when views with XMLTABLE and DEFAULT are present - @wolfgangwalther
- #1724, Fix wrong CORS header Authentication -> Authorization - @wolfgangwalther
- #2120, Fix reading database configuration properly when `=` is present in value - @wolfgangwalther
- #2135, Remove trigger functions from schema cache and OpenAPI output, because they can't be called directly anyway. - @wolfgangwalther
- #2101, Remove aggregates, procedures and window functions from the schema cache and OpenAPI output. - @wolfgangwalther
- #2153, Fix --dump-schema running with a wrong PG version. - @wolfgangwalther
- #2042, Keep working when EMFILE(Too many open files) is reached. - @steve-chavez
- #2147, Ignore `Content-Type` headers for `GET` requests when calling RPCs. - @laurenceisla
-    + Previously, `GET` without parameters, but with `Content-Type: text/plain` or `Content-Type: application/octet-stream` would fail with `404 Not Found`, even if a function without arguments was available.
- #2239, Fix misleading disambiguation error where the content of the `relationship` key looks like valid syntax - @laurenceisla
- #2294, Disable parallel GC for better performance on higher core CPUs - @steve-chavez
- #1076, Fix using CPU while idle - @steve-chavez
+ - #2165, Fix json/jsonb columns should not have type in OpenAPI spec - @clrnd
+ - #2020, Execute deferred constraint triggers when using `Prefer: tx=rollback` - @wolfgangwalther
+ - #2077, Fix `is` not working with upper or mixed case values like `NULL, TrUe, FaLsE` - @steve-chavez
+ - #2024, Fix schema cache loading when views with XMLTABLE and DEFAULT are present - @wolfgangwalther
+ - #1724, Fix wrong CORS header Authentication -> Authorization - @wolfgangwalther
+ - #2120, Fix reading database configuration properly when `=` is present in value - @wolfgangwalther
+ - #2135, Remove trigger functions from schema cache and OpenAPI output, because they can't be called directly anyway. - @wolfgangwalther
+ - #2101, Remove aggregates, procedures and window functions from the schema cache and OpenAPI output. - @wolfgangwalther
+ - #2153, Fix --dump-schema running with a wrong PG version. - @wolfgangwalther
+ - #2042, Keep working when EMFILE(Too many open files) is reached. - @steve-chavez
+ - #2147, Ignore `Content-Type` headers for `GET` requests when calling RPCs. - @laurenceisla
+   + Previously, `GET` without parameters, but with `Content-Type: text/plain` or `Content-Type: application/octet-stream` would fail with `404 Not Found`, even if a function without arguments was available.
+ - #2239, Fix misleading disambiguation error where the content of the `relationship` key looks like valid syntax - @laurenceisla
+ - #2294, Disable parallel GC for better performance on higher core CPUs - @steve-chavez
+ - #1076, Fix using CPU while idle - @steve-chavez

 ## [9.0.0] - 2021-11-25

@@ -1,20 +0,0 @@
-- Settings to allow building with plain cabal. If this was
-- named just cabal.project, it would interfere with the default
-- nix build.
-
-packages: .
-
-- Example of depending on a forked repository (the same dependency
-- would be mentioned in nix/overlays/haskell-packages.nix and
-- stack.yaml, and should refer to a main branch commit of the
-- repository.
--
-- source-repository-package
--  type: git
--  location: https://github.com/PostgREST/hasql-pool.git
--  tag: 4d462c4d47d762effefc7de6c85eaed55f144f1d
-
-source-repository-package
-  type: git
-  location: https://github.com/PostgREST/postgresql-libpq.git
-  tag: 890a0a16cf57dd401420fdc6c7d576fb696003bc
@@ -1,11 +1,9 @@
-{ system ? builtins.currentSystem }:
-
 let
  name =
    "postgrest";

  compiler =
-    "ghc924";
+    "ghc8107";

  # PostgREST source files, filtered based on the rules in the .gitignore files
  # and file extensions. We want to include as litte as possible, as the files
@@ -36,40 +34,24 @@ let
      allOverlays.build-toolbox
      allOverlays.checked-shell-script
      allOverlays.gitignore
-      allOverlays.postgis
-      (allOverlays.postgresql-default { inherit patches; })
+      allOverlays.postgresql-default
      allOverlays.postgresql-legacy
      allOverlays.postgresql-future
      (allOverlays.haskell-packages { inherit compiler; })
-      allOverlays.slocat
    ];

  # Evaluated expression of the Nixpkgs repository.
  pkgs =
-    import nixpkgs { inherit overlays system; };
+    import nixpkgs { inherit overlays; };

  postgresqlVersions =
    [
-      {
-        name = "postgresql-16";
-        postgresql = pkgs.postgresql_16.withPackages (p: [
-          p.postgis
-          (p.pg_safeupdate.overrideAttrs (old: {
-            installPhase = ''
-              mkdir -p $out/bin
-              cp safeupdate.dylib safeupdate.so || true
-              install -D safeupdate.so -t $out/lib
-            '';
-          }))
-        ]);
-      }
-      { name = "postgresql-15"; postgresql = pkgs.postgresql_15.withPackages (p: [ p.postgis p.pg_safeupdate ]); }
-      { name = "postgresql-14"; postgresql = pkgs.postgresql_14.withPackages (p: [ p.postgis p.pg_safeupdate ]); }
-      { name = "postgresql-13"; postgresql = pkgs.postgresql_13.withPackages (p: [ p.postgis p.pg_safeupdate ]); }
-      { name = "postgresql-12"; postgresql = pkgs.postgresql_12.withPackages (p: [ p.postgis p.pg_safeupdate ]); }
-      { name = "postgresql-11"; postgresql = pkgs.postgresql_11.withPackages (p: [ p.postgis p.pg_safeupdate ]); }
-      { name = "postgresql-10"; postgresql = pkgs.postgresql_10.withPackages (p: [ p.postgis p.pg_safeupdate ]); }
-      { name = "postgresql-9.6"; postgresql = pkgs.postgresql_9_6.withPackages (p: [ p.postgis p.pg_safeupdate ]); }
+      { name = "postgresql-14"; postgresql = pkgs.postgresql_14; }
+      { name = "postgresql-13"; postgresql = pkgs.postgresql_13; }
+      { name = "postgresql-12"; postgresql = pkgs.postgresql_12; }
+      { name = "postgresql-11"; postgresql = pkgs.postgresql_11; }
+      { name = "postgresql-10"; postgresql = pkgs.postgresql_10; }
+      { name = "postgresql-9.6"; postgresql = pkgs.postgresql_9_6; }
    ];

  patches =
@@ -79,16 +61,10 @@ let
  postgrest =
    pkgs.haskell.packages."${compiler}".callCabal2nix name src { };

-  # Functionality that derives a fully static Haskell package based on
+  # Function that derives a fully static Haskell package based on
  # nh2/static-haskell-nix
  staticHaskellPackage =
-    import nix/static-haskell-package.nix { inherit nixpkgs system compiler patches allOverlays; };
-
-  # Static executable.
-  postgrestStatic =
-    lib.justStaticExecutables (lib.dontCheck (staticHaskellPackage name src).package);
-
-  packagesStatic = (staticHaskellPackage name src).survey;
+    import nix/static-haskell-package.nix { inherit nixpkgs compiler patches allOverlays; };

  # Options passed to cabal in dev tools and tests
  devCabalOptions =
@@ -114,6 +90,10 @@ rec {
  postgrestPackage =
    lib.dontCheck postgrest;

+  # Static executable.
+  postgrestStatic =
+    lib.justStaticExecutables (lib.dontCheck (staticHaskellPackage name src));
+
  # Profiled dynamic executable.
  postgrestProfiled =
    lib.enableExecutableProfiling (
@@ -135,13 +115,14 @@ rec {
  cabalTools =
    pkgs.callPackage nix/tools/cabalTools.nix { inherit devCabalOptions postgrest; };

-  withTools =
-    pkgs.callPackage nix/tools/withTools.nix { inherit cabalTools devCabalOptions postgresqlVersions postgrest; };
-
  # Development tools.
  devTools =
    pkgs.callPackage nix/tools/devTools.nix { inherit tests style devCabalOptions hsie withTools; };

+  # Docker images and loading script.
+  docker =
+    pkgs.callPackage nix/tools/docker { postgrest = postgrestStatic; };
+
  # Load testing tools.
  loadtest =
    pkgs.callPackage nix/tools/loadtest.nix { inherit withTools; };
@@ -168,14 +149,8 @@ rec {
      inherit postgrest devCabalOptions withTools;
      ghc = pkgs.haskell.compiler."${compiler}";
      inherit (pkgs.haskell.packages."${compiler}") hpc-codecov;
-      inherit (pkgs.haskell.packages."${compiler}") weeder;
    };
-} // pkgs.lib.optionalAttrs pkgs.stdenv.isLinux rec {
-  # Static executable.
-  inherit postgrestStatic;
-  inherit packagesStatic;

-  # Docker images and loading script.
-  docker =
-    pkgs.callPackage nix/tools/docker { postgrest = postgrestStatic; };
+  withTools =
+    pkgs.callPackage nix/tools/withTools.nix { inherit devCabalOptions postgresqlVersions postgrest; };
 }
@@ -2,11 +2,15 @@

 module Main (main) where

+import qualified Data.Map.Strict as M
+
 import System.IO (BufferMode (..), hSetBuffering)

 import qualified PostgREST.App as App
 import qualified PostgREST.CLI as CLI

+import PostgREST.Config (readPGRSTEnvironment)
+
 import Protolude

 #ifndef mingw32_HOST_OS
@@ -16,7 +20,8 @@ import qualified PostgREST.Unix as Unix
 main :: IO ()
 main = do
  setBuffering
-  opts <- CLI.readCLIShowHelp
+  hasPGRSTEnv <- not . M.null <$> readPGRSTEnvironment
+  opts <- CLI.readCLIShowHelp hasPGRSTEnv
  CLI.main installSignalHandlers runAppInSocket opts

 installSignalHandlers :: App.SignalHandlerInstaller
@@ -5,14 +5,24 @@ for developing, testing and building PostgREST.

 ## Getting started with Nix

-You'll need to [get Nix](https://nixos.org/download.html). Follow the recommended installation for your operating system from the official download website.
+You'll need to [get Nix](https://nixos.org/download.html). The installer will
+create your Nix store in the `/nix/` directory, where all build artifacts and
+their dependencies will be stored. It will also link the Nix executables like
+`nix-env`, `nix-build` and `nix-shell` into your PATH. Nix will manage all
+other PostgREST dependencies from here on out. To clean up older build
+artifacts from the `/nix/store`, you can run `nix-collect-garbage`.
+
+If you are on a system that does not support nix, for example Windows, you can
+run the nix development environment in a docker container. Inside the `nix/`
+directory run `docker-compose run --rm nix` to start the docker container. This
+will set up the binary cache and launch `nix-shell` automatically.

 ## Building PostgREST

 To build PostgREST from your local checkout of the repository, run:

 ```bash
-$ nix-build --attr postgrestPackage
+nix-build --attr postgrestPackage

 ```

@@ -29,10 +39,10 @@ We recommend that you use the PostgREST binary cache on

 ```bash
 # Install cachix:
-$ nix-env -iA cachix -f https://cachix.org/api/v1/install
+nix-env -iA cachix -f https://cachix.org/api/v1/install

 # Set cachix up to use the PostgREST binary cache:
-$ cachix use postgrest
+cachix use postgrest

 ```

@@ -46,7 +56,7 @@ following command will put you into a new shell that has GHC and Cabal on the
 PATH:

 ```bash
-$ nix-shell
+nix-shell

 ```

@@ -136,16 +146,16 @@ Note: Once inside nix-shell, the utilities work from any directory inside
 the PostgREST repo. Paths are resolved relative to the repo root:

 ```bash
-[nix-shell]$ cd src
+$ cd src
 # Even though the current directory is ./src, the config path must still start
 # from the repo root:
-[nix-shell]$ postgrest-run test/io/configs/simple.conf
+$ postgrest-run test/io/configs/simple.conf
 ```

 ## Testing

-In nix-shell, you'll find utility scripts that make it very easy to run our
-test suite, including setting up all required dependencies and
+In nix-shell, you'll find utility scripts that make it very easy to run the
+Haskell test suite, including setting up all required dependencies and
 temporary test databases:

 ```bash
@@ -167,60 +177,12 @@ run with `postgrest-test-io`. The test runner under the hood is

 ```bash
 # Filter the tests to run by name, including all that contain 'config':
-[nix-shell]$ postgrest-test-io -k config
+postgrest-test-io -k config

 # Run tests in parallel using xdist, specifying the number of processes:
-[nix-shell]$ postgrest-test-io -n auto
-[nix-shell]$ postgrest-test-io -n 8
-```
+postgrest-test-io -n auto
+postgrest-test-io -n 8

-The memory tests check that we don't surpass a memory threshold for big request bodies.
-
-```bash
-# Build the dependencies needed for the memory test
-$ nix-shell --arg memory true
-
-# Run the memory test
-[nix-shell]$ postgrest-test-memory
-```
-
-The loadtests ensure that performance doesn't drop on a change. Underlyingly they use
-[vegeta](https://github.com/tsenart/vegeta).
-
-```bash
-# Run the loadtests on the latest commit(HEAD)
-[nix-shell]$ postgrest-loadtest
-
-# You can loadtest comparing to a different branch
-[nix-shell]$ postgrest-loadtest-against master
-
-# You can simulate latency client/postgrest and postgrest/database
-[nix-shell]$ PGRST_DELAY=5ms PGDELAY=5ms postgrest-loadtest
-
-# You can build postgrest directly with cabal for faster iteration
-[nix-shell]$ PGRST_BUILD_CABAL=1 postgrest-loadtest
-
-# Produce a markdown report to be used on CI
-[nix-shell]$ postgrest-loadtest-report
-```
-
-doctests for some of our modules are also available:
-
-```bash
-[nix-shell]$ postgrest-test-doctest
-```
-
-## Code coverage
-
-Code coverage is available under the `postgrest-coverage` command. This will produce a `./coverage` directory that can be visualized with a simple http server.
-
-```bash
-# Will run all the tests and produce a coverage dir
-[nix-shell]$ postgrest-coverage
-
-# Visualize the output
-[nix-shell]$ cd coverage
-[nix-shell]$ python -mSimpleHTTPServer 8080
 ```

 ## Linting and styling code
@@ -24,22 +24,21 @@ import qualified Data.Text                               as T
 import qualified Data.Text.IO                            as T
 import qualified Dot
 import qualified GHC
-import qualified GHC.Paths
 import qualified Language.Haskell.GHC.ExactPrint.Parsers as ExactPrint
 import qualified Options.Applicative                     as O
 import qualified System.FilePath                         as FP

+import Bag                        (bagToList)
 import Data.Aeson.Encode.Pretty   (encodePretty)
 import Data.Function              ((&))
 import Data.List                  (intercalate)
 import Data.Maybe                 (catMaybes, mapMaybe)
 import Data.Text                  (Text)
-import GHC.Data.Bag               (bagToList)
 import GHC.Generics               (Generic)
 import GHC.Hs.Extension           (GhcPs)
-import GHC.Types.Name.Occurrence  (occNameString)
-import GHC.Types.Name.Reader      (rdrNameOcc)
-import GHC.Unit.Module.Name       (moduleNameString)
+import Module                     (moduleNameString)
+import OccName                    (occNameString)
+import RdrName                    (rdrNameOcc)
 import System.Directory.Recursive (getFilesRecursive)
 import System.Exit                (exitFailure)

@@ -198,11 +197,11 @@ sourceSymbols source = do
      return $ concatMap (importSymbols source filepath . GHC.unLoc) hsmodImports

 -- | Parse a Haskell module
-parseModule :: FilePath -> IO GHC.HsModule
+parseModule :: String -> IO (GHC.HsModule GhcPs)
 parseModule filepath = do
-  result <- ExactPrint.parseModule GHC.Paths.libdir filepath
+  result <- ExactPrint.parseModule filepath
  case result of
-    Right hsmod ->
+    Right (_, hsmod) ->
      return $ GHC.unLoc hsmod
    Left errs ->
      fail $ "Errors with " <> show filepath <> ":\n    "
@@ -213,6 +212,7 @@ parseModule filepath = do
 -- If the import is a wildcard, i.e. no symbols are selected for import, then
 -- only one item is returned.
 importSymbols :: FilePath -> FilePath -> GHC.ImportDecl GhcPs -> [ImportedSymbol]
+importSymbols _ _  (GHC.XImportDecl _) = mempty
 importSymbols source filepath GHC.ImportDecl{..} =
  case ideclHiding of
    Just (hiding, syms) ->
@@ -16,20 +16,15 @@ let
  ghc = ghcWithPackages modules;
  hsie =
    runCommand "haskellimports" { inherit name src; }
-      ''
-        cd $TMP
-        cp $src $TMP/Main.hs
-        ${ghc}/bin/ghc -O -Werror -Wall -package ghc Main.hs -o Main
-        cp Main $out
-      '';
+      "${ghc}/bin/ghc -O -Werror -Wall -package ghc $src -o $out";
  bin =
    runCommand name { inherit hsie name; }
      ''
        mkdir -p $out/bin
        ln -s $hsie $out/bin/$name
      '';
-  bash-completion =
+  bashCompletion =
    runCommand "${name}-bash-completion" { inherit bin name; }
      "$bin/bin/$name --bash-completion-script $bin/bin/$name > $out";
 in
-hsie // { inherit bash-completion bin; }
+hsie // { inherit bashCompletion bin; }
@@ -1,6 +1,6 @@
 # Pinned version of Nixpkgs, generated with postgrest-nixpkgs-upgrade.
 {
-  date = "2023-03-25";
-  rev = "dbf5322e93bcc6cfc52268367a8ad21c09d76fea";
-  tarballHash = "0lwk4v9dkvd28xpqch0b0jrac4xl9lwm6snrnzx8k5lby72kmkng";
+  date = "2021-11-02";
+  rev = "7053541084bf5ce2921ef307e5585d39d7ba8b3f";
+  tarballHash = "1flhh5d4zy43x6060hvzjb5hi5cmc51ivc0nwmija9n8d35kcc4x";
 }
@@ -1,11 +1,11 @@
-# Creates an environment that exposes bash-completion arguments from all checkedShellScripts
+# Creates an environment that exposes bashCompletion arguments from all checkedShellScripts
 { buildEnv }:
 { name
 , tools
 , extra ? { }
 }:
 let
-  bash-completion = builtins.map (tool: tool.bash-completion) tools;
+  bashCompletion = builtins.map (tool: tool.bashCompletion) tools;

  env = buildEnv {
    inherit name;
@@ -13,4 +13,4 @@ let
  };

 in
-env // { inherit bash-completion; } // extra
+env // { inherit bashCompletion; } // extra
@@ -2,7 +2,7 @@
 # directly, or use the .bin attribute to get the script in a bin/ directory,
 # to be used in a path for example.
 { argbash
-, bash
+, bash_5
 , coreutils
 , git
 , lib
@@ -58,7 +58,7 @@ let
        sed '/_positionals_count + 1/a\\t\t\t\tset -- "''${@:1:1}" "--" "''${@:2}"' -i $out
      '';

-  bash-completion =
+  bashCompletion =
    runCommand "${name}-completion" { } (
      ''
        ${argbash}/bin/argbash --type completion --strip all ${argsTemplate}/${name}.m4 > $out
@@ -77,7 +77,7 @@ let

      text =
        ''
-          #!${bash}/bin/bash
+          #!${bash_5}/bin/bash
          source ${argsParser}
          set -euo pipefail
        ''
@@ -138,4 +138,4 @@ let
  script =
    runCommand name { inherit bin name; } "ln -s $bin/bin/$name $out";
 in
-script // { inherit bin bash-completion; }
+script // { inherit bin bashCompletion; }
@@ -3,9 +3,7 @@
  checked-shell-script = import ./checked-shell-script;
  gitignore = import ./gitignore.nix;
  haskell-packages = import ./haskell-packages.nix;
-  postgis = import ./postgis.nix;
  postgresql-default = import ./postgresql-default.nix;
  postgresql-legacy = import ./postgresql-legacy.nix;
  postgresql-future = import ./postgresql-future.nix;
-  slocat = import ./slocat.nix;
 }
@@ -12,8 +12,8 @@ self: super:
      gitignoreSrc = super.fetchFromGitHub {
        owner = "hercules-ci";
        repo = "gitignore";
-        rev = "a20de23b925fd8264fd7fad6454652e142fd7f73";
-        sha256 = "sha256-8DFJjXG8zqoONA1vXtgeKXy68KdJL5UaXR8NtVMUbx8=";
+        rev = "211907489e9f198594c0eb0ca9256a1949c9d412";
+        sha256 = "06j7wpvj54khw0z10fjyi31kpafkr6hi1k0di13k1xp8kywvfyx8";
      };
    in
    (super.callPackage gitignoreSrc { }).gitignoreSource;
@@ -13,10 +13,13 @@ let
      #       {
      #         pkg = "protolude";
      #         ver = "0.3.0";
-      #         sha256 = "<sha256>";
+      #         sha256 = "0iwh4wsjhb7pms88lw1afhdal9f86nrrkkvv65f9wxbd1b159n72";
      #       }
      #       { };
      #
+      # To get the sha256:
+      #   nix-prefetch-url --unpack https://hackage.haskell.org/package/protolude-0.3.0/protolude-0.3.0.tar.gz
+
      # To temporarily pin unreleased versions from GitHub:
      #   <name> =
      #     prev.callCabal2nixWithOptions "<name>" (super.fetchFromGitHub {
@@ -26,36 +29,53 @@ let
      #       sha256 = "<sha256>";
      #    }) "--subpath=<subpath>" {};
      #
-      # To fill in the sha256:
-      #   update-nix-fetchgit nix/overlays/haskell-packages.nix
+      # To get the sha256:
+      #   nix-prefetch-url --unpack https://github.com/<owner>/<repo>/archive/<commit>.tar.gz

-      postgresql-libpq = lib.dontCheck
-        (prev.callCabal2nix "postgresql-libpq"
-          (super.fetchFromGitHub {
-            owner = "PostgREST";
-            repo = "postgresql-libpq";
-            rev = "890a0a16cf57dd401420fdc6c7d576fb696003bc"; # master
-            sha256 = "1wmyhldk0k14y8whp1p4akrkqxf5snh8qsbm7fv5f7kz95nyffd0";
-          })
-          { });
-
-      hasql-notifications = lib.dontCheck
-        (prev.callHackageDirect
+      protolude =
+        prev.callHackageDirect
          {
-            pkg = "hasql-notifications";
-            ver = "0.2.0.6";
-            sha256 = "sha256-7PyFlB2B70njudOjaX6tk1m77ol9vnF5fI0LF86kVAI=";
+            pkg = "protolude";
+            ver = "0.3.1";
+            sha256 = "0gf0mn1ycllr69kdq1p07qf7935s10jz0nnhynwqy3d6nmycxr5j";
+          }
+          { };
+
+      wai-extra =
+        prev.callHackageDirect
+          {
+            pkg = "wai-extra";
+            ver = "3.1.8";
+            sha256 = "1ha8sxc2ii7k7xs5nm06wfwqmf4f1p2acp4ya0jnx6yn6551qps4";
+          }
+          { };
+
+      wai-logger =
+        prev.callHackageDirect
+          {
+            pkg = "wai-logger";
+            ver = "2.3.7";
+            sha256 = "1d23fdbwbahr3y1vdyn57m1qhljy22pm5cpgb20dy6mlxzdb30xd";
+          }
+          { };
+
+      warp =
+        lib.dontCheck (prev.callHackageDirect
+          {
+            pkg = "warp";
+            ver = "3.3.19";
+            sha256 = "0y3jj4bhviss6ff9lwxki0zbdcl1rb398bk4s80zvfpnpy7p94cx";
          }
          { });

-      hasql-pool = lib.dontCheck
-        (prev.callHackageDirect
-          {
-            pkg = "hasql-pool";
-            ver = "0.10";
-            sha256 = "sha256-kHzoqtNV9BFWnn1h560JRqMooQRwxokVKgDRBexamNI=";
-          }
-          { });
+      hasql-dynamic-statements =
+        lib.dontCheck (lib.unmarkBroken prev.hasql-dynamic-statements);
+
+      hasql-implicits =
+        lib.dontCheck (lib.unmarkBroken prev.hasql-implicits);
+
+      ptr =
+        lib.dontCheck (lib.unmarkBroken prev.ptr);
    } // extraOverrides final prev;
 in
 {
@@ -1,27 +0,0 @@
-final: prev:
-let
-  postgis_3_2_3 = rec {
-    version = "3.2.3";
-    src = final.fetchurl {
-      url = "https://download.osgeo.org/postgis/source/postgis-${version}.tar.gz";
-      sha256 = "sha256-G02LXHVuWrpZ77wYM7Iu/k1lYneO7KVvpJf+susTZow=";
-    };
-  };
-in
-{
-  postgresql_11 = prev.postgresql_11.override { this = final.postgresql_11; } // {
-    pkgs = prev.postgresql_11.pkgs // {
-      postgis = prev.postgresql_11.pkgs.postgis.overrideAttrs (_: postgis_3_2_3);
-    };
-  };
-  postgresql_10 = prev.postgresql_10.override { this = final.postgresql_11; } // {
-    pkgs = prev.postgresql_10.pkgs // {
-      postgis = prev.postgresql_10.pkgs.postgis.overrideAttrs (_: postgis_3_2_3);
-    };
-  };
-  postgresql_9_6 = prev.postgresql_9_6.override { this = final.postgresql_11; } // {
-    pkgs = prev.postgresql_9_6.pkgs // {
-      postgis = prev.postgresql_9_6.pkgs.postgis.overrideAttrs (_: postgis_3_2_3);
-    };
-  };
-}
@@ -1,8 +1,5 @@
-{ patches }: self: super:
+self: super:
 # Overlay that sets the default version of PostgreSQL.
-with patches;
 {
-  postgresql = super.postgresql_15.overrideAttrs ({ patches ? [ ], ... }: {
-    patches = patches ++ [ postgresql-atexit ];
-  });
+  postgresql = super.postgresql_14;
 }
@@ -4,16 +4,16 @@ self: super:
 {
  ## Example for including a postgresql version from a specific nixpks commit:
  ##
-  postgresql_16 =
-    let
-      rev = "5148520bfab61f99fd25fb9ff7bfbb50dad3c9db";
-      tarballHash = "1dfjmz65h8z4lk845724vypzmf3dbgsdndjpj8ydlhx6c7rpcq3p";
-
-      pinnedPkgs =
-        builtins.fetchTarball {
-          url = "https://github.com/nixos/nixpkgs/archive/${rev}.tar.gz";
-          sha256 = tarballHash;
-        };
-    in
-    (import pinnedPkgs { }).pkgs.postgresql_16;
+  #  postgresql_14 =
+  #    let
+  #      rev = "76b1e16c6659ccef7187ca69b287525fea133244";
+  #      tarballHash = "1vsahpcx80k2bgslspb0sa6j4bmhdx77sw6la455drqcrqhdqj6a";
+  #
+  #      pinnedPkgs =
+  #        builtins.fetchTarball {
+  #          url = "https://github.com/nixos/nixpkgs/archive/${rev}.tar.gz";
+  #          sha256 = tarballHash;
+  #        };
+  #    in
+  #    (import pinnedPkgs { }).pkgs.postgresql_14;
 }
@@ -2,33 +2,19 @@ self: super:
 # Overlay that adds legacy versions of PostgreSQL that are supported by
 # PostgREST.
 {
-  # PostgreSQL 9.6 was removed from Nixpkgs with
-  # https://github.com/NixOS/nixpkgs/commit/757dd008b2f2926fc0f7688fa8189f930ea47521
+  # PostgreSQL 9.5 was removed from Nixpkgs with
+  # https://github.com/NixOS/nixpkgs/commit/72ab382fb6b729b0d654f2c03f5eb25b39f11fbb
  # We pin its parent commit to get the last version that was available.
-  postgresql_9_6 =
-    let
-      rev = "571cbf3d1db477058303cef8754fb85a14e90eb7";
-      tarballHash = "0q74wn418i1bn5sssacmw8ykpmqvzr0s93sj6pbs3rf6bf134fkz";
-      pinnedPkgs =
-        builtins.fetchTarball {
-          url = "https://github.com/nixos/nixpkgs/archive/${rev}.tar.gz";
-          sha256 = tarballHash;
-        };
-    in
-    (import pinnedPkgs { }).pkgs.postgresql_9_6;
-
-  # PostgreSQL 10 was removed from Nixpkgs with
-  # https://github.com/NixOS/nixpkgs/commit/aa1483114bb329fee7e1266100b8d8921ed4723f
-  # We pin its parent commit to get the last version that was available.
-  postgresql_10 =
-    let
-      rev = "79661ba7e2fb96ebefbb537458a5bbae9dc5bd1a";
-      tarballHash = "0rn796pfn4sg90ai9fdnwmr10a2s835p1arazzgz46h6s5cxvq97";
-      pinnedPkgs =
-        builtins.fetchTarball {
-          url = "https://github.com/nixos/nixpkgs/archive/${rev}.tar.gz";
-          sha256 = tarballHash;
-        };
-    in
-    (import pinnedPkgs { }).pkgs.postgresql_10;
+  # postgresql_9_5 =
+  #  let
+  #    rev = "55ac7d4580c9ab67848c98cb9519317a1cc399c8";
+  #    tarballHash = "02ffj9f8s1hwhmxj85nx04sv64qb6jm7w0122a1dz9n32fymgklj";
+  #
+  #    pinnedPkgs =
+  #      builtins.fetchTarball {
+  #        url = "https://github.com/nixos/nixpkgs/archive/${rev}.tar.gz";
+  #        sha256 = tarballHash;
+  #      };
+  #  in
+  #  (import pinnedPkgs { }).pkgs.postgresql_9_5;
 }
@@ -1,13 +0,0 @@
-final: prev:
-{
-  slocat = prev.buildGoModule {
-    name = "slocat";
-    src = prev.fetchFromGitHub {
-      owner = "robx";
-      repo = "slocat";
-      rev = "52e7512c6029fd00483e41ccce260a3b4b9b3b64";
-      sha256 = "sha256-qn6luuh5wqREu3s8RfuMCP5PKdS2WdwPrujRYTpfzQ8=";
-    };
-    vendorSha256 = "sha256-pQpattmS9VmO3ZIQUFn66az8GSmB4IvYhTTCFn6SUmo=";
-  };
-}
@@ -18,12 +18,7 @@
        done
      '';

-  static-haskell-nix-ncurses =
-    ./static-haskell-nix-ncurses.patch;
-  static-haskell-nix-ghc-bignum =
-    ./static-haskell-nix-ghc-bignum.patch;
-  static-haskell-nix-openssl =
-    ./static-haskell-nix-openssl.patch;
-  postgresql-atexit =
-    ./postgresql-atexit.patch;
+  # See: https://github.com/NixOS/nixpkgs/pull/87879
+  nixpkgs-openssl-split-runtime-dependencies-of-static-builds =
+    ./nixpkgs-openssl-split-runtime-dependencies-of-static-builds.patch;
 }
@@ -0,0 +1,76 @@
+diff --git a/pkgs/development/libraries/openssl/default.nix b/pkgs/development/libraries/openssl/default.nix
+index d4be8cc2428..3979698711f 100644
+--- a/pkgs/development/libraries/openssl/default.nix
+++ b/pkgs/development/libraries/openssl/default.nix
+@@ -50,9 +50,21 @@ let
+       substituteInPlace crypto/async/arch/async_posix.h \
+         --replace '!defined(__ANDROID__) && !defined(__OpenBSD__)' \
+                   '!defined(__ANDROID__) && !defined(__OpenBSD__) && 0'
+    '' + optionalString static
+    # On static builds, the ENGINESDIR will be empty, but its path will be
+    # compiled into the library. In order to minimize the runtime dependencies
+    # of packages that statically link openssl, we move it into the OPENSSLDIR,
+    # which will be separated into the 'etc' output.
+    ''
+      substituteInPlace Configurations/unix-Makefile.tmpl \
+        --replace 'ENGINESDIR=$(libdir)/engines-{- $sover_dirname -}' \
+                  'ENGINESDIR=$(OPENSSLDIR)/engines-{- $sover_dirname -}'
+     '';
+ 
+-    outputs = [ "bin" "dev" "out" "man" ] ++ optional withDocs "doc";
+    outputs = [ "bin" "dev" "out" "man" ]
+      ++ optional withDocs "doc"
+      # Separate output for the runtime dependencies of the static build.
+      ++ optional static "etc";
+     setOutputFlags = false;
+     separateDebugInfo =
+       !stdenv.hostPlatform.isDarwin &&
+@@ -101,7 +113,17 @@ let
+     configureFlags = [
+       "shared" # "shared" builds both shared and static libraries
+       "--libdir=lib"
+-      "--openssldir=etc/ssl"
+      (if !static then
+         "--openssldir=etc/ssl"
+       else
+         # Separate the OPENSSLDIR into its own output, as its path will be
+         # compiled into 'libcrypto.a'. This makes it a runtime dependency of
+         # any package that statically links openssl, so we want to keep that
+         # output minimal. We need to prepend '/.' to the path in order to make
+         # it appear absolute before variable expansion, the 'prefix' would be
+         # prepended to it otherwise.
+         "--openssldir=/.$(etc)/etc/ssl"
+      )
+     ] ++ lib.optionals withCryptodev [
+       "-DHAVE_CRYPTODEV"
+       "-DUSE_CRYPTODEV_DIGESTS"
+@@ -131,6 +153,9 @@ let
+       if [ -n "$(echo $out/lib/*.so $out/lib/*.dylib $out/lib/*.dll)" ]; then
+           rm "$out/lib/"*.a
+       fi
+
+      # 'etc' is a separate output on static builds only.
+      etc=$out
+     '' + lib.optionalString (!stdenv.hostPlatform.isWindows)
+       # Fix bin/c_rehash's perl interpreter line
+       #
+@@ -152,14 +177,15 @@ let
+       mv $out/include $dev/
+ 
+       # remove dependency on Perl at runtime
+-      rm -r $out/etc/ssl/misc
+      rm -r $etc/etc/ssl/misc
+ 
+-      rmdir $out/etc/ssl/{certs,private}
+      rmdir $etc/etc/ssl/{certs,private}
+     '';
+ 
+     postFixup = lib.optionalString (!stdenv.hostPlatform.isWindows) ''
+-      # Check to make sure the main output doesn't depend on perl
+-      if grep -r '${buildPackages.perl}' $out; then
+      # Check to make sure the main output and the static runtime dependencies
+      # don't depend on perl
+      if grep -r '${buildPackages.perl}' $out $etc; then
+         echo "Found an erroneous dependency on perl ^^^" >&2
+         exit 1
+       fi
@@ -1,11 +0,0 @@
--- a/src/interfaces/libpq/Makefile
-+++ b/src/interfaces/libpq/Makefile
-@@ -118,7 +118,7 @@ backend_src = $(top_srcdir)/src/backend
- libpq-refs-stamp: $(shlib)
- ifneq ($(enable_coverage), yes)
- ifeq (,$(filter aix solaris,$(PORTNAME)))
-	@if nm -A -u $< 2>/dev/null | grep -v __cxa_atexit | grep exit; then \
-+	@if nm -A -u $< 2>/dev/null | grep " exit"; then \
- 		echo 'libpq must not be calling any function which invokes exit'; exit 1; \
- 	fi
- endif
@@ -1,12 +0,0 @@
-diff --git a/survey/default.nix b/survey/default.nix
-index 70afbbc..28cb0e9 100644
--- a/survey/default.nix
-+++ b/survey/default.nix
-@@ -81,6 +81,7 @@ let
-   # `.override` and the likes).
-   isProperHaskellPackage = val:
-     lib.isDerivation val && # must pass lib.isDerivation
-+    val.pname != "ghc-bignum" &&
-     val ? env; # must have an .env key
- 
-   # Function that tells us if a given Haskell package has an executable.
@@ -1,13 +0,0 @@
-diff --git a/survey/default.nix b/survey/default.nix
-index 46d8066..a47f214 100644
--- a/survey/default.nix
-+++ b/survey/default.nix
-@@ -1519,7 +1519,7 @@ let
-                   [
-                     "--enable-executable-static" # requires `useFixedCabal`
-                     # `enableShared` seems to be required to avoid `recompile with -fPIC` errors on some packages.
-                    "--extra-lib-dirs=${final.ncurses.override { enableStatic = true; enableShared = true; }}/lib"
-+                    "--extra-lib-dirs=${final.ncurses.override { enableStatic = true; }}/lib"
-                   ]
-                   # TODO Figure out why this and the below libffi are necessary.
-                   #      `working` and `workingStackageExecutables` don't seem to need that,
@@ -1,12 +0,0 @@
-diff --git a/survey/default.nix b/survey/default.nix
-index cf1bd31..9d34753 100644
--- a/survey/default.nix
-+++ b/survey/default.nix
-@@ -736,6 +736,7 @@ let
-     openblas = previous.openblas.override { enableStatic = true; };
- 
-     openssl = previous.openssl.override { static = true; };
-+    openssl_1_1 = previous.openssl_1_1.override { static = true; };
- 
-     libsass = previous.libsass.overrideAttrs (old: { dontDisableStatic = true; });
- 
@@ -1,5 +1,5 @@
 # Derive a fully static Haskell package based on musl instead of glibc.
-{ nixpkgs, system, compiler, patches, allOverlays }:
+{ nixpkgs, compiler, patches, allOverlays }:

 name: src:
 let
@@ -17,9 +17,14 @@ let
    patches.applyPatches "patched-static-haskell-nix"
      static-haskell-nix
      [
-        patches.static-haskell-nix-ncurses
-        patches.static-haskell-nix-ghc-bignum
-        patches.static-haskell-nix-openssl
+        # No patches currently required.
+      ];
+
+  patchedNixpkgs =
+    patches.applyPatches "patched-nixpkgs"
+      nixpkgs
+      [
+        patches.nixpkgs-openssl-split-runtime-dependencies-of-static-builds
      ];

  extraOverrides =
@@ -35,7 +40,7 @@ let
  overlays =
    [
      allOverlays.postgresql-future
-      (allOverlays.postgresql-default { inherit patches; })
+      allOverlays.postgresql-default
      (allOverlays.haskell-packages { inherit compiler extraOverrides; })
      # Disable failing tests for postgresql on musl that should have no impact
      # on the libpq that we need (collate.icu.utf8 and foreign regression
@@ -45,13 +50,13 @@ let
      )
    ];

-  # Apply our overlay to nixpkgs.
+  # Apply our overlay to the given pkgs.
  normalPkgs =
-    import nixpkgs { inherit overlays system; };
+    import patchedNixpkgs { inherit overlays; };

  defaultCabalPackageVersionComingWithGhc =
    {
-      ghc924 = "Cabal_3_6_3_0";
+      ghc8107 = "Cabal_3_2_1_0";
    }."${compiler}";

  # The static-haskell-nix 'survey' derives a full static set of Haskell
@@ -59,7 +64,4 @@ let
  survey =
    import "${patched-static-haskell-nix}/survey" { inherit normalPkgs compiler defaultCabalPackageVersionComingWithGhc; };
 in
-{
-  inherit survey;
-  package = survey.haskellPackages."${name}";
-}
+survey.haskellPackages."${name}"
@@ -28,8 +28,6 @@ let
      ''
        # clean old coverage data, too
        rm -rf .hpc coverage
-        # clean old hie files
-        find . -name "*.hie" -type f -delete
        exec ${cabal-install}/bin/cabal v2-clean
      '';

@@ -37,22 +35,12 @@ let
    checkedShellScript
      {
        name = "postgrest-run";
-        docs = "Run PostgREST after building it interactively with cabal-install";
-        args =
-          [
-            "ARG_USE_ENV([PGRST_DB_ANON_ROLE], [postgrest_test_anonymous], [PostgREST anonymous role])"
-            "ARG_USE_ENV([PGRST_DB_POOL], [1], [PostgREST pool size])"
-            "ARG_USE_ENV([PGRST_DB_POOL_ACQUISITION_TIMEOUT], [1], [PostgREST pool size])"
-            "ARG_LEFTOVERS([PostgREST arguments])"
-          ];
+        docs = "Run PostgREST after buidling it interactively with cabal-install";
+        args = [ "ARG_LEFTOVERS([PostgREST arguments])" ];
        inRootDir = true;
        withEnv = postgrest.env;
      }
      ''
-        export PGRST_DB_ANON_ROLE
-        export PGRST_DB_POOL
-        export PGRST_DB_POOL_ACQUISITION_TIMEOUT
-
        exec ${cabal-install}/bin/cabal v2-run ${devCabalOptions} --verbose=0 -- \
          postgrest "''${_arg_leftovers[@]}"
      '';
@@ -77,6 +77,7 @@ let
      }
      ''
        ${tests}/bin/postgrest-test-spec
+        ${tests}/bin/postgrest-test-querycost
        ${tests}/bin/postgrest-test-doctests
        ${tests}/bin/postgrest-test-io
        ${style}/bin/postgrest-lint
@@ -137,7 +138,7 @@ let
          # to the hook file.
          sed -i -e '/postgrest-git-hooks/d' .git/hooks/pre-{commit,push} 2> /dev/null || true

-          if [ disable != "$_arg_operation" ]; then
+          if [ disabled != "$_arg_mode" ]; then
            # The nix-shell && + nix-shell || pattern makes sure we can run the hook
            # in a pure nix-shell, where nix-shell itself is not available, too.

@@ -164,18 +165,6 @@ let
          # The following unsets all GIT_ variables.
          unset "''${!GIT_@}"

-          # shellcheck disable=SC2317
-          function restore () {
-            ref="$(git stash list --format=format:%gD --grep "$1" -n1)"
-            # this will avoid merge conflicts when applying the stash
-            ${git}/bin/git restore --source="$ref" .
-            # restore untracked files, too. could fail with no files
-            if [ "$(git show --numstat --format=oneline "$ref^3" | wc -l)" -gt 1 ]; then
-              ${git}/bin/git restore --overlay --source="$ref^3" .
-            fi
-            ${git}/bin/git stash drop "$ref"
-          }
-
          case "$_arg_mode" in
            basic)
              case "$_arg_hook" in
@@ -190,7 +179,7 @@ let
                  if [ "$(git stash list --grep $stash)" ]; then
                    # Only create the stash pop trap, if we actually created a stash.
                    # Otherwise stash pop will cause havoc.
-                    trap 'restore "$stash"' EXIT
+                    trap '${git}/bin/git stash pop $(git stash list --format=format:%gD --grep "$stash" -n1)' EXIT
                  fi

                  ${style}/bin/postgrest-style
@@ -215,7 +204,7 @@ let
                  if [ "$(git stash list --grep $stash)" ]; then
                    # Only create the stash pop trap, if we actually created a stash.
                    # Otherwise stash pop will cause havoc.
-                    trap 'restore "$stash"' EXIT
+                    trap '${git}/bin/git stash pop $(git stash list --format=format:%gD --grep "$stash" -n1)' EXIT
                  fi

                  ${style}/bin/postgrest-style
@@ -304,5 +293,4 @@ buildToolbox
    hsieGraphModules
    hsieGraphSymbols
  ];
-  extra = { inherit pushCachix; };
 }
@@ -93,18 +93,3 @@ Image efficiency score: 100 %

 Count   Total Space  Path
 ```
-
-# Deriving from the optimized image
-
-Since the docker image is minimal, it does not contain a shell or other utilities.
-To derive a non-minimal image, you can do the following:
-
-```Dockerfile
-# derive from any base image you want
-FROM alpine:latest
-
-# copy PostgREST over
-COPY --from=postgrest/postgrest /bin/postgrest /bin
-
-# add your other stuff
-```
@@ -8,7 +8,7 @@ let
    dockerTools.buildImage {
      name = "postgrest";
      tag = "latest";
-      copyToRoot = postgrest;
+      contents = postgrest;

      # Set the current time as the image creation date. This makes the build
      # non-reproducible, but that should not be an issue for us.
@@ -45,26 +45,19 @@ let
        inRootDir = true;
      }
      ''
-        # previously required settings to make this work with older branches
-        export PGRST_DB_ANON_ROLE="postgrest_test_anonymous"
-        export PGRST_DB_URI="postgresql://"
-        export PGRST_DB_SCHEMAS="test"
-
        export PGRST_DB_CONFIG="false"
        export PGRST_DB_POOL="1"
        export PGRST_DB_TX_END="rollback-allow-override"
        export PGRST_LOG_LEVEL="crit"

        mkdir -p "$(dirname "$_arg_output")"
-        abs_output="$(realpath "$_arg_output")"

        # shellcheck disable=SC2145
        ${withTools.withPg} --fixtures "$_arg_testdir"/fixtures.sql \
-        ${withTools.withSlowPg} \
        ${withTools.withPgrst} \
-        ${withTools.withSlowPgrst} \
-        sh -c "cd \"$_arg_testdir\" && ${runner} -targets targets.http -output \"$abs_output\" \"''${_arg_leftovers[@]}\""
-        ${vegeta}/bin/vegeta report -type=text "$_arg_output"
+        sh -c "cd \"$_arg_testdir\" && ${runner} -targets targets.http \"''${_arg_leftovers[@]}\"" \
+          | tee "$_arg_output" \
+          | ${vegeta}/bin/vegeta report -type=text
      '';

  loadtestAgainst =
@@ -1,6 +1,5 @@
 { buildToolbox
 , checkedShellScript
-, coreutils
 , curl
 , jq
 , nix
@@ -34,7 +33,7 @@ let
        commitHash="$(${curl}/bin/curl "${refUrl}" -H "${githubV3Header}" | ${jq}/bin/jq -r .object.sha)"
        tarballUrl="${tarballUrlBase}$commitHash.tar.gz"
        tarballHash="$(${nix}/bin/nix-prefetch-url --unpack "$tarballUrl")"
-        currentDate="$(${coreutils}/bin/date --iso)"
+        currentDate="$(date --iso)"

        cat > nix/nixpkgs-version.nix << EOF
        # Pinned version of Nixpkgs, generated with ${name}.
@@ -40,98 +40,15 @@ let
        )"

        repo_url="https://hub.docker.com/v2/repositories/$DOCKER_REPO/postgrest/"
-        echo "Patching both descriptions at $repo_url ..."
+        echo "Patching both descriptions at $repo_url ..." 
        ${curl}/bin/curl --fail -X PATCH "$repo_url" \
          -H "Authorization: JWT $token" \
          --data-urlencode description@${description} \
          --data-urlencode full_description@${fullDescription}
      '';
-
-  release =
-    checkedShellScript
-      {
-        name = "postgrest-release";
-        docs = "Patch postgrest.cabal, CHANGELOG.md, tag and push all in one go.";
-        args = [ "ARG_POSITIONAL_SINGLE([version], [Version to release], [pre])" ];
-        inRootDir = true;
-      }
-      ''
-        trap "echo You need to be on the main branch to proceed. Exiting ..." ERR
-        [ "$(git rev-parse --abbrev-ref HEAD)" == "main" ]
-        trap "" ERR
-
-        trap "echo You have uncommitted changes in postgrest.cabal. Exiting ..." ERR
-        git diff --exit-code HEAD postgrest.cabal > /dev/null
-        trap "" ERR
-
-        current_version="$(grep -oP '^version:\s*\K.*' postgrest.cabal)"
-        # shellcheck disable=SC2034
-        IFS=. read -r major minor patch pre <<< "$current_version"
-        echo "Current version is $current_version"
-
-        today_date="$(date '+%Y%m%d')"
-        today_date_for_changelog="$(date '+%Y-%m-%d')"
-        bump_pre="$major.$minor.$patch.$today_date"
-        bump_pre_minor="$major.$((minor+1)).0.$today_date"
-        bump_patch="$major.$minor.$((patch+1))"
-        bump_minor="$major.$((minor+1)).0"
-        bump_major="$((major+1)).0.0"
-
-        PS3="Please select the new version: "
-        select new_version in "$bump_pre" "$bump_pre_minor" "$bump_patch" "$bump_minor" "$bump_major"; do
-          case "$REPLY" in
-            1|2|3|4|5)
-              echo "Selected $new_version"
-              break
-              ;;
-            *)
-            echo "Invalid option $REPLY"
-            ;;
-          esac
-        done
-
-        echo "Updating postgrest.cabal ..."
-        sed -i -E "s/^(version:\s+).*$/\1$new_version/" postgrest.cabal > /dev/null
-
-        echo "Committing ..."
-        git add postgrest.cabal > /dev/null
-
-        if [[ "$new_version" != "$bump_pre" && "$new_version" != "$bump_pre_minor" ]]; then
-          echo "Updating CHANGELOG.md ..."
-          sed -i -E "s/Unreleased/&\n\n## [$new_version] - $today_date_for_changelog/" CHANGELOG.md > /dev/null
-          git add CHANGELOG.md > /dev/null
-        fi
-
-        git commit -m "bump version to $new_version" > /dev/null
-
-        echo "Tagging ..."
-        git tag "v$new_version" > /dev/null
-
-        trap "echo Remote not found. Please push manually ..." ERR
-        remote="$(git remote -v | grep PostgREST/postgrest | grep push | cut -f1)"
-        trap "" ERR
-
-        push="git push --atomic $remote main v$new_version"
-
-        echo "To push both the branch and the new tag, the following will be run:"
-        echo
-        echo "$push"
-        echo
-
-        read -r -p 'Proceed? (y/N) ' REPLY
-        case "$REPLY" in
-          y|Y)
-            $push
-            ;;
-          *)
-            echo "Aborting ..."
-            ;;
-        esac
-      '';
-
 in
 buildToolbox
 {
  name = "postgrest-release";
-  tools = [ dockerHubDescription release ];
+  tools = [ dockerHubDescription ];
 }
@@ -55,7 +55,7 @@ write from scratch.
 # Usage

 To learn how to use this container, see the [PostgREST Docker
-documentation](https://postgrest.org/en/stable/install.html#docker).
+documentation](https://postgrest.com/en/stable/install.html#docker).

 You can configure the PostgREST image by setting
 [enviroment variables](https://postgrest.org/en/stable/configuration.html).
@@ -66,5 +66,5 @@ The image is built from scratch using
 [Nix](https://nixos.org/nixpkgs/manual/#sec-pkgs-dockerTools) instead of a
 `Dockerfile`, which yields a higly secure and optimized image. This is also why
 no commands are listed in the image history. See the [PostgREST
-respository](https://github.com/PostgREST/postgrest/tree/main/nix/tools/docker) for
+respository](https://github.com/PostgREST/postgrest/tree/main/nix/docker) for
 details on the build process and how to inspect the image.
@@ -46,7 +46,7 @@ let

        trap "echo postgrest-style-check failed. Run postgrest-style to fix issues automatically." ERR

-        ${git}/bin/git diff-index --exit-code HEAD -- '*.hs' '*.lhs' '*.nix' '*.py'
+        ${git}/bin/git diff-index --exit-code HEAD -- '*.hs' '*.lhs' '*.nix'
      '';

  lint =
@@ -69,7 +69,8 @@ let
        echo "Linting bash scripts..."
        ${shellcheck}/bin/shellcheck \
          .github/get_cirrusci_freebsd \
-          .github/release
+          .github/release \
+          test/with_tmp_db

        echo "Linting workflows..."
        ${actionlint}/bin/actionlint
@@ -3,17 +3,14 @@
 , checkedShellScript
 , devCabalOptions
 , ghc
-, glibcLocales ? null
+, glibcLocales
 , gnugrep
+, haskellPackages
 , hpc-codecov
-, hostPlatform
 , jq
-, lib
 , postgrest
 , python3
 , runtimeShell
-, stdenv
-, weeder
 , withTools
 , yq
 }:
@@ -22,14 +19,24 @@ let
    checkedShellScript
      {
        name = "postgrest-test-spec";
-        docs = "Run the Haskell test suite. Use --match PATTERN for running individual specs";
-        args = [ "ARG_LEFTOVERS([hspec arguments])" ];
+        docs = "Run the Haskell test suite";
        inRootDir = true;
        withEnv = postgrest.env;
      }
      ''
-        ${withTools.withPg} ${cabal-install}/bin/cabal v2-run ${devCabalOptions} \
-          test:spec -- "''${_arg_leftovers[@]}"
+        ${withTools.withPg} ${cabal-install}/bin/cabal v2-run ${devCabalOptions} test:spec
+      '';
+
+  testQuerycost =
+    checkedShellScript
+      {
+        name = "postgrest-test-querycost";
+        docs = "Run the Haskell test suite for query costs";
+        inRootDir = true;
+        withEnv = postgrest.env;
+      }
+      ''
+        ${withTools.withPg} ${cabal-install}/bin/cabal v2-run ${devCabalOptions} test:querycost
      '';

  testDoctests =
@@ -68,7 +75,7 @@ let
    python3.withPackages (ps: [
      ps.pyjwt
      ps.pytest
-      ps.pytest-xdist
+      ps.pytest_xdist
      ps.pyyaml
      ps.requests
      ps.requests-unixsocket
@@ -78,7 +85,7 @@ let
    checkedShellScript
      {
        name = "postgrest-test-io";
-        docs = "Run the pytest-based IO tests. Add -k to run tests that match a given expression.";
+        docs = "Run the pytest-based IO tests.";
        args = [ "ARG_LEFTOVERS([pytest arguments])" ];
        inRootDir = true;
        withEnv = postgrest.env;
@@ -93,7 +100,7 @@ let
    checkedShellScript
      {
        name = "postgrest-dump-schema";
-        docs = "Dump the loaded schema's SchemaCache as a yaml file.";
+        docs = "Dump the loaded schema's DbStructure as a yaml file.";
        inRootDir = true;
        withEnv = postgrest.env;
        withPath = [ jq ];
@@ -116,69 +123,64 @@ let
        withEnv = postgrest.env;
        withTmpDir = true;
      }
-      (
-        # required for `hpc markup` in CI; glibcLocales is not available e.g. on Darwin
-        lib.optionalString (stdenv.isLinux && hostPlatform.libc == "glibc") ''
-          export LOCALE_ARCHIVE="${glibcLocales}/lib/locale/locale-archive"
-        '' +
+      ''
+        export LOCALE_ARCHIVE="${glibcLocales}/lib/locale/locale-archive"

-        ''
-          # clean up previous coverage reports
-          mkdir -p coverage
-          rm -rf coverage/*
+        # clean up previous coverage reports
+        mkdir -p coverage
+        rm -rf coverage/*

-          # build once before running all the tests
-          ${cabal-install}/bin/cabal v2-build ${devCabalOptions} exe:postgrest lib:postgrest test:spec
+        # build once before running all the tests
+        ${cabal-install}/bin/cabal v2-build ${devCabalOptions} exe:postgrest lib:postgrest test:spec test:querycost

-          (
-            trap 'echo Found dead code: Check file list above.' ERR ;
-            ${weeder}/bin/weeder --config=./test/weeder.dhall
-          )
+        ${haskellPackages.weeder}/bin/weeder --config=./test/weeder.dhall || echo Found dead code: Check file list above.

-          # collect all tests
-          HPCTIXFILE="$tmpdir"/io.tix \
-            ${withTools.withPg} -f test/io/fixtures.sql ${cabal-install}/bin/cabal v2-exec ${devCabalOptions} -- \
-            ${ioTestPython}/bin/pytest -v test/io
+        # collect all tests
+        HPCTIXFILE="$tmpdir"/io.tix \
+          ${withTools.withPg} -f test/io/fixtures.sql ${cabal-install}/bin/cabal v2-exec ${devCabalOptions} -- \
+          ${ioTestPython}/bin/pytest -v test/io
+          
+        HPCTIXFILE="$tmpdir"/spec.tix \
+          ${withTools.withPg} ${cabal-install}/bin/cabal v2-run ${devCabalOptions} test:spec

-          HPCTIXFILE="$tmpdir"/spec.tix \
-            ${withTools.withPg} ${cabal-install}/bin/cabal v2-run ${devCabalOptions} test:spec
+        HPCTIXFILE="$tmpdir"/querycost.tix \
+          ${withTools.withPg} ${cabal-install}/bin/cabal v2-run ${devCabalOptions} test:querycost

-          # Note: No coverage for doctests, as doctests leverage GHCi and GHCi does not support hpc
+        # Note: No coverage for doctests, as doctests leverage GHCi and GHCi does not support hpc

-          # collect all the tix files
-          ${ghc}/bin/hpc sum  --union --exclude=Paths_postgrest --output="$tmpdir"/tests.tix \
-            "$tmpdir"/io*.tix "$tmpdir"/spec.tix
+        # collect all the tix files
+        ${ghc}/bin/hpc sum  --union --exclude=Paths_postgrest --output="$tmpdir"/tests.tix \
+          "$tmpdir"/io*.tix "$tmpdir"/spec.tix "$tmpdir"/querycost.tix

-          # prepare the overlay
-          ${ghc}/bin/hpc overlay --output="$tmpdir"/overlay.tix test/coverage.overlay
-          ${ghc}/bin/hpc sum --union --output="$tmpdir"/tests-overlay.tix "$tmpdir"/tests.tix "$tmpdir"/overlay.tix
+        # prepare the overlay
+        ${ghc}/bin/hpc overlay --output="$tmpdir"/overlay.tix test/coverage.overlay
+        ${ghc}/bin/hpc sum --union --output="$tmpdir"/tests-overlay.tix "$tmpdir"/tests.tix "$tmpdir"/overlay.tix

-          # check nothing in the overlay is actually tested
-          ${ghc}/bin/hpc map --function=inv --output="$tmpdir"/inverted.tix "$tmpdir"/tests.tix
-          ${ghc}/bin/hpc combine --function=sub \
-            --output="$tmpdir"/check.tix "$tmpdir"/overlay.tix "$tmpdir"/inverted.tix
-          # returns zero exit code if any count="<non-zero>" lines are found, i.e.
-          # something is covered by both the overlay and the tests
-          if ${ghc}/bin/hpc report --xml "$tmpdir"/check.tix | ${gnugrep}/bin/grep -qP 'count="[^0]'
-          then
-            ${ghc}/bin/hpc markup --highlight-covered --destdir=coverage/overlay "$tmpdir"/overlay.tix || true
-            ${ghc}/bin/hpc markup --highlight-covered --destdir=coverage/check "$tmpdir"/check.tix || true
-            echo "ERROR: Something is covered by both the tests and the overlay:"
-            echo "file://$(pwd)/coverage/check/hpc_index.html"
-            exit 1
-          else
-            # copy the result .tix file to the coverage/ dir to make it available to postgrest-coverage-draft-overlay, too
-            cp "$tmpdir"/tests-overlay.tix coverage/postgrest.tix
-            # prepare codecov json report
-            ${hpc-codecov}/bin/hpc-codecov --mix=.hpc --out=coverage/codecov.json coverage/postgrest.tix
+        # check nothing in the overlay is actually tested
+        ${ghc}/bin/hpc map --function=inv --output="$tmpdir"/inverted.tix "$tmpdir"/tests.tix
+        ${ghc}/bin/hpc combine --function=sub \
+          --output="$tmpdir"/check.tix "$tmpdir"/overlay.tix "$tmpdir"/inverted.tix
+        # returns zero exit code if any count="<non-zero>" lines are found, i.e.
+        # something is covered by both the overlay and the tests
+        if ${ghc}/bin/hpc report --xml "$tmpdir"/check.tix | ${gnugrep}/bin/grep -qP 'count="[^0]'
+        then
+          ${ghc}/bin/hpc markup --highlight-covered --destdir=coverage/overlay "$tmpdir"/overlay.tix || true
+          ${ghc}/bin/hpc markup --highlight-covered --destdir=coverage/check "$tmpdir"/check.tix || true
+          echo "ERROR: Something is covered by both the tests and the overlay:"
+          echo "file://$(pwd)/coverage/check/hpc_index.html"
+          exit 1
+        else
+          # copy the result .tix file to the coverage/ dir to make it available to postgrest-coverage-draft-overlay, too
+          cp "$tmpdir"/tests-overlay.tix coverage/postgrest.tix
+          # prepare codecov json report
+          ${hpc-codecov}/bin/hpc-codecov --mix=.hpc --out=coverage/codecov.json coverage/postgrest.tix

-            # create html and stdout reports
-            ${ghc}/bin/hpc markup --destdir=coverage coverage/postgrest.tix
-            echo "file://$(pwd)/coverage/hpc_index.html"
-            ${ghc}/bin/hpc report coverage/postgrest.tix "''${_arg_leftovers[@]}"
-          fi
-        ''
-      );
+          # create html and stdout reports
+          ${ghc}/bin/hpc markup --destdir=coverage coverage/postgrest.tix
+          echo "file://$(pwd)/coverage/hpc_index.html"
+          ${ghc}/bin/hpc report coverage/postgrest.tix "''${_arg_leftovers[@]}"
+        fi
+      '';

  coverageDraftOverlay =
    checkedShellScript
@@ -192,26 +194,6 @@ let
        sed -i 's|^module \(.*\):|module \1/|g' test/coverage.overlay
      '';

-  checkStatic =
-    checkedShellScript
-      {
-        name = "postgrest-check-static";
-        docs = "Verify that the argument is a static executable.";
-        args = [ "ARG_POSITIONAL_SINGLE([executable], [Executable])" ];
-        inRootDir = true;
-        withEnv = postgrest.env;
-      }
-      ''
-        exe="$_arg_executable"
-        ldd_output=$(ldd "$exe" 2>&1 || true)
-        if ! grep -q "not a dynamic executable" <<< "$ldd_output"; then
-          echo "not a static executable, ldd output:"
-          echo "$ldd_output"
-          exit 1
-        fi
-        "$exe" --help
-      '';
-
 in
 buildToolbox
 {
@@ -219,12 +201,12 @@ buildToolbox
  tools =
    [
      testSpec
+      testQuerycost
      testDoctests
      testSpecIdempotence
      testIO
      dumpSchema
      coverage
      coverageDraftOverlay
-      checkStatic
    ];
 }
@@ -1,7 +1,6 @@
-{ bash-completion
+{ bashCompletion
 , buildToolbox
 , cabal-install
-, cabalTools
 , checkedShellScript
 , curl
 , devCabalOptions
@@ -9,20 +8,15 @@
 , lib
 , postgresqlVersions
 , postgrest
-, slocat
 , writeText
 }:
 let
  withTmpDb =
    { name, postgresql }:
-    let
-      commandName = "postgrest-with-${name}";
-      superuserRole = "postgres";
-    in
    checkedShellScript
      {
-        name = commandName;
-        docs = "Run the given command in a temporary database with ${name}. If you wish to mutate the database, login with the '${superuserRole}' role.";
+        name = "postgrest-with-${name}";
+        docs = "Run the given command in a temporary database with ${name}";
        args =
          [
            "ARG_OPTIONAL_SINGLE([fixtures], [f], [SQL file to load fixtures from], [test/spec/fixtures/load.sql])"
@@ -31,8 +25,7 @@ let
            "ARG_USE_ENV([PGUSER], [postgrest_test_authenticator], [Authenticator PG role])"
            "ARG_USE_ENV([PGDATABASE], [postgres], [PG database name])"
            "ARG_USE_ENV([PGRST_DB_SCHEMAS], [test], [Schema to expose])"
-            "ARG_USE_ENV([PGTZ], [utc], [Timezone to use])"
-            "ARG_USE_ENV([PGOPTIONS], [-c search_path=public,test], [PG options to use])"
+            "ARG_USE_ENV([PGRST_DB_ANON_ROLE], [postgrest_test_anonymous], [Anonymous PG role])"
          ];
        positionalCompletion = "_command";
        inRootDir = true;
@@ -42,7 +35,7 @@ let
      }
      ''
        # avoid starting multiple layers of withTmpDb
-        if test -v PGHOST; then
+        if test -v PGRST_DB_URI; then
          exec "$_arg_command" "''${_arg_leftovers[@]}"
        fi

@@ -60,27 +53,21 @@ let
        export PGHOST="$tmpdir/socket"
        export PGUSER
        export PGDATABASE
+        export PGRST_DB_URI="postgresql:///$PGDATABASE?host=$PGHOST&user=$PGUSER"
        export PGRST_DB_SCHEMAS
-        export PGTZ
-        export PGOPTIONS
-
-        HBA_FILE="$tmpdir/pg_hba.conf"
-        echo "local $PGDATABASE some_protected_user password" > "$HBA_FILE"
-        echo "local $PGDATABASE all trust" >> "$HBA_FILE"
+        export PGRST_DB_ANON_ROLE

        log "Initializing database cluster..."
        # We try to make the database cluster as independent as possible from the host
        # by specifying the timezone, locale and encoding.
-        # initdb -U creates a superuser(man initdb)
-        PGTZ=UTC initdb --no-locale --encoding=UTF8 --nosync -U "${superuserRole}" --auth=trust \
+        PGTZ=UTC initdb --no-locale --encoding=UTF8 --nosync -U "$PGUSER" --auth=trust \
          >> "$setuplog"

        log "Starting the database cluster..."
        # Instead of listening on a local port, we will listen on a unix domain socket.
-        pg_ctl -l "$tmpdir/db.log" -w start -o "-F -c listen_addresses=\"\" -c hba_file=$HBA_FILE -k $PGHOST -c log_statement=\"all\" " \
+        pg_ctl -l "$tmpdir/db.log" -w start -o "-F -c listen_addresses=\"\" -k $PGHOST" \
          >> "$setuplog"

-        # shellcheck disable=SC2317
        stop () {
          log "Stopping the database cluster..."
          pg_ctl stop -m i >> "$setuplog"
@@ -88,17 +75,10 @@ let
        }
        trap stop EXIT

-        log "Creating a minimally privileged $PGUSER connection role..."
-        createuser "$PGUSER" -U "${superuserRole}" --host="$tmpdir/socket" --no-createdb --no-inherit --no-superuser --no-createrole --no-replication --login
-
-        log "Loading fixtures under the ${superuserRole} role..."
-        psql -U "${superuserRole}" -v PGUSER="$PGUSER" -v ON_ERROR_STOP=1 -f "$_arg_fixtures" >> "$setuplog"
+        log "Loading fixtures..."
+        psql -v ON_ERROR_STOP=1 -f "$_arg_fixtures" >> "$setuplog"

        log "Done. Running command..."
-
-        echo "${commandName}: You can connect with: psql 'postgres:///$PGDATABASE?host=$tmpdir/socket' -U ${superuserRole}"
-        echo "${commandName}: You can tail the logs with: tail -f $tmpdir/db.log"
-
        ("$_arg_command" "''${_arg_leftovers[@]}")
      '';

@@ -148,81 +128,6 @@ let

  withPg = builtins.head withPgVersions;

-  withSlowPg =
-    checkedShellScript
-      {
-        name = "postgrest-with-slow-pg";
-        docs = "Run the given command with simulated high latency postgresql";
-        args =
-          [
-            "ARG_POSITIONAL_SINGLE([command], [Command to run])"
-            "ARG_LEFTOVERS([command arguments])"
-            "ARG_USE_ENV([PGHOST], [], [PG host (socket name)])"
-            "ARG_USE_ENV([PGDELAY], [0ms], [extra PG latency (duration)])"
-          ];
-        positionalCompletion = "_command";
-        inRootDir = true;
-        redirectTixFiles = false;
-        withTmpDir = true;
-      }
-      ''
-        delay="''${PGDELAY:-0ms}"
-        echo "delaying data to/from postgres by $delay"
-
-        REALPGHOST="$PGHOST"
-        export PGHOST="$tmpdir/socket"
-        mkdir -p "$PGHOST"
-
-        ${slocat}/bin/slocat -delay "$delay" -src "$PGHOST/.s.PGSQL.5432" -dst "$REALPGHOST/.s.PGSQL.5432" &
-        SLOCAT_PID=$!
-        # shellcheck disable=SC2317
-        stop_slocat() {
-          kill "$SLOCAT_PID" || true
-          wait "$SLOCAT_PID" || true
-        }
-        trap stop_slocat EXIT
-        sleep 1 # should wait for socket file to appear instead
-
-        ("$_arg_command" "''${_arg_leftovers[@]}")
-      '';
-
-  withSlowPgrst =
-    checkedShellScript
-      {
-        name = "postgrest-with-slow-postgrest";
-        docs = "Run the given command with simulated high latency postgrest";
-        args =
-          [
-            "ARG_POSITIONAL_SINGLE([command], [Command to run])"
-            "ARG_LEFTOVERS([command arguments])"
-            "ARG_USE_ENV([PGRST_SERVER_UNIX_SOCKET], [], [PostgREST host (socket name)])"
-            "ARG_USE_ENV([PGRST_DELAY], [0ms], [extra PostgREST latency (duration)])"
-          ];
-        positionalCompletion = "_command";
-        inRootDir = true;
-        redirectTixFiles = false;
-        withTmpDir = true;
-      }
-      ''
-        delay="''${PGRST_DELAY:-0ms}"
-        echo "delaying data to/from PostgREST by $delay"
-
-        REAL_PGRST_SERVER_UNIX_SOCKET="$PGRST_SERVER_UNIX_SOCKET"
-        export PGRST_SERVER_UNIX_SOCKET="$tmpdir/postgrest.socket"
-
-        ${slocat}/bin/slocat -delay "$delay" -src "$PGRST_SERVER_UNIX_SOCKET" -dst "$REAL_PGRST_SERVER_UNIX_SOCKET" &
-        SLOCAT_PID=$!
-        # shellcheck disable=SC2317
-        stop_slocat() {
-          kill "$SLOCAT_PID" || true
-          wait "$SLOCAT_PID" || true
-        }
-        trap stop_slocat EXIT
-        sleep 1 # should wait for socket file to appear instead
-
-        ("$_arg_command" "''${_arg_leftovers[@]}")
-      '';
-
  withGit =
    let
      name = "postgrest-with-git";
@@ -342,37 +247,19 @@ let
      ''
        export PGRST_SERVER_UNIX_SOCKET="$tmpdir"/postgrest.socket

-        rm -f result
-        if [ -z "''${PGRST_BUILD_CABAL:-}" ]; then
-          echo -n "Building postgrest (nix)... "
-          nix-build -A postgrestPackage > "$tmpdir"/build.log 2>&1 || {
-            echo "failed, output:"
-            cat "$tmpdir"/build.log
-            exit 1
-          }
-          PGRST_CMD=./result/bin/postgrest
-        else
-          echo -n "Building postgrest (cabal)... "
-          postgrest-build
-          PGRST_CMD=postgrest-run
-        fi
-        echo "done."
+        ${cabal-install}/bin/cabal v2-build ${devCabalOptions} > "$tmpdir"/build.log 2>&1
+        ${cabal-install}/bin/cabal v2-run ${devCabalOptions} --verbose=0 -- \
+          postgrest ${legacyConfig} > "$tmpdir"/run.log 2>&1 &

-        echo -n "Starting postgrest... "
-        $PGRST_CMD ${legacyConfig} > "$tmpdir"/run.log 2>&1 &
-        pid=$!
-        # shellcheck disable=SC2317
+        # to get the pid of the postgrest process, we need to jump through some hoops
+        # $! will return the pid of cabal - but killing this, will not propagate to postgrest
+        pid=$(timeout -s TERM 1 ${waitForPgrstPid})
        cleanup() {
          kill "$pid" || true
        }
        trap cleanup EXIT

-        timeout -s TERM 5 ${waitForPgrstReady} || {
-          echo "timed out, output:"
-          cat "$tmpdir"/run.log
-          exit 1
-        }
-        echo "done."
+        timeout -s TERM 5 ${waitForPgrstReady}

        ("$_arg_command" "''${_arg_leftovers[@]}")
      '';
@@ -381,7 +268,7 @@ in
 buildToolbox
 {
  name = "postgrest-with";
-  tools = [ withPgAll withGit withPgrst withSlowPg withSlowPgrst ] ++ withPgVersions;
+  tools = [ withPgAll withGit withPgrst ] ++ withPgVersions;
  # make withTools available for other nix files
-  extra = { inherit withGit withPg withPgAll withPgrst withSlowPg withSlowPgrst; };
+  extra = { inherit withGit withPg withPgAll withPgrst; };
 }
@@ -1,8 +1,8 @@
 name:               postgrest
-version:            11.2.2
+version:            9.0.1
 synopsis:           REST API for any Postgres database
 description:        Reads the schema of a PostgreSQL database and creates RESTful routes
-                    for tables, views, and functions, supporting all HTTP methods that security
+                    for tables, views, and functions, supporting all HTTP verbs that security
                    permits.
 license:            MIT
 license-file:       LICENSE
@@ -34,8 +34,7 @@ library
  default-extensions: OverloadedStrings
                      NoImplicitPrelude
  hs-source-dirs:     src
-  exposed-modules:    PostgREST.Admin
-                      PostgREST.App
+  exposed-modules:    PostgREST.App
                      PostgREST.AppState
                      PostgREST.Auth
                      PostgREST.CLI
@@ -44,42 +43,37 @@ library
                      PostgREST.Config.JSPath
                      PostgREST.Config.PgVersion
                      PostgREST.Config.Proxy
+                      PostgREST.ContentType
                      PostgREST.Cors
-                      PostgREST.SchemaCache
-                      PostgREST.SchemaCache.Identifiers
-                      PostgREST.SchemaCache.Routine
-                      PostgREST.SchemaCache.Relationship
-                      PostgREST.SchemaCache.Representations
-                      PostgREST.SchemaCache.Table
+                      PostgREST.DbStructure
+                      PostgREST.DbStructure.Identifiers
+                      PostgREST.DbStructure.Proc
+                      PostgREST.DbStructure.Relationship
+                      PostgREST.DbStructure.Table
                      PostgREST.Error
+                      PostgREST.GucHeader
                      PostgREST.Logger
-                      PostgREST.MediaType
-                      PostgREST.Query
+                      PostgREST.Middleware
+                      PostgREST.OpenAPI
                      PostgREST.Query.QueryBuilder
                      PostgREST.Query.SqlFragment
                      PostgREST.Query.Statements
-                      PostgREST.Plan
-                      PostgREST.Plan.CallPlan
-                      PostgREST.Plan.MutatePlan
-                      PostgREST.Plan.ReadPlan
-                      PostgREST.Plan.Types
                      PostgREST.RangeQuery
-                      PostgREST.ApiRequest
-                      PostgREST.ApiRequest.Preferences
-                      PostgREST.ApiRequest.QueryParams
-                      PostgREST.ApiRequest.Types
-                      PostgREST.Response
-                      PostgREST.Response.OpenAPI
-                      PostgREST.Response.GucHeader
+                      PostgREST.Request.ApiRequest
+                      PostgREST.Request.DbRequestBuilder
+                      PostgREST.Request.Parsers
+                      PostgREST.Request.Preferences
+                      PostgREST.Request.Types
                      PostgREST.Version
+                      PostgREST.Workers
  other-modules:      Paths_postgrest
-  build-depends:      base                      >= 4.9 && < 4.17
-                    , HTTP                      >= 4000.3.7 && < 4000.5
+  build-depends:      base                      >= 4.9 && < 4.16
+                    , HTTP                      >= 4000.3.7 && < 4000.4
                    , Ranged-sets               >= 0.3 && < 0.5
-                    , aeson                     >= 2.0.3 && < 2.2
+                    , aeson                     >= 1.4.7 && < 1.6
                    , auto-update               >= 0.1.4 && < 0.2
                    , base64-bytestring         >= 1 && < 1.3
-                    , bytestring                >= 0.10.8 && < 0.12
+                    , bytestring                >= 0.10.8 && < 0.11
                    , case-insensitive          >= 1.2 && < 1.3
                    , cassava                   >= 0.4.5 && < 0.6
                    , configurator-pg           >= 0.2 && < 0.3
@@ -87,44 +81,35 @@ library
                    , contravariant-extras      >= 0.3.3 && < 0.4
                    , cookie                    >= 0.4.2 && < 0.5
                    , either                    >= 4.4.1 && < 5.1
-                    , extra                     >= 1.7.0 && < 2.0
-                    , fuzzyset                  >= 0.2.3
                    , gitrev                    >= 1.2 && < 1.4
-                    , hasql                     >= 1.6.1.1 && < 1.7
-                    , hasql-dynamic-statements  >= 0.3.1 && < 0.4
-                    , hasql-notifications       >= 0.2.0.6 && < 0.3
-                    , hasql-pool                >= 0.10 && < 0.11
+                    , hasql                     >= 1.4 && < 1.5
+                    , hasql-dynamic-statements  == 0.3.1
+                    , hasql-notifications       >= 0.1 && < 0.3
+                    , hasql-pool                >= 0.5 && < 0.6
                    , hasql-transaction         >= 1.0.1 && < 1.1
                    , heredoc                   >= 0.2 && < 0.3
                    , http-types                >= 0.12.2 && < 0.13
                    , insert-ordered-containers >= 0.2.2 && < 0.3
                    , interpolatedstring-perl6  >= 1 && < 1.1
-                    , jose                      >= 0.8.5.1 && < 0.11
-                    , lens                      >= 4.14 && < 5.3
-                    , lens-aeson                >= 1.0.1 && < 1.3
+                    , jose                      >= 0.8.1 && < 0.9
+                    , lens                      >= 4.14 && < 5.1
+                    , lens-aeson                >= 1.0.1 && < 1.2
                    , mtl                       >= 2.2.2 && < 2.3
-                    , network                   >= 2.6 && < 3.2
                    , network-uri               >= 2.6.1 && < 2.8
-                    , optparse-applicative      >= 0.13 && < 0.18
+                    , optparse-applicative      >= 0.13 && < 0.17
                    , parsec                    >= 3.1.11 && < 3.2
                    , protolude                 >= 0.3.1 && < 0.4
                    , regex-tdfa                >= 1.2.2 && < 1.4
                    , retry                     >= 0.7.4 && < 0.10
                    , scientific                >= 0.3.4 && < 0.4
-                    , swagger2                  >= 2.4 && < 2.9
+                    , swagger2                  >= 2.4 && < 2.7
                    , text                      >= 1.2.2 && < 1.3
-                    , time                      >= 1.6 && < 1.12
+                    , time                      >= 1.6 && < 1.11
                    , unordered-containers      >= 0.2.8 && < 0.3
-                    , vault                     >= 0.3.1.5 && < 0.4
-                    , vector                    >= 0.11 && < 0.14
+                    , vector                    >= 0.11 && < 0.13
                    , wai                       >= 3.2.1 && < 3.3
                    , wai-cors                  >= 0.2.5 && < 0.3
                    , wai-extra                 >= 3.1.8 && < 3.2
-                    -- We already depend on wai-logger >= 2.3.7 indirectly via wai-extra,
-                    -- but we want to depend on 2.4.0 which fixes 'unknownSocket' log output
-                    -- for unix sockets; this is tested in test/io/test_io.py. See
-                    -- https://github.com/kazu-yamamoto/logger/commit/3a71ca70afdbb93d4ecf0083eeba1fbbbcab3fc3
-                    , wai-logger                >= 2.4.0
                    , warp                      >= 3.3.19 && < 3.4
                      -- -fno-spec-constr may help keep compile time memory use in check,
                      --   see https://gitlab.haskell.org/ghc/ghc/issues/16017#note_219304
@@ -145,6 +130,7 @@ library
    build-depends:
      unix
      , directory >= 1.2.6 && < 1.4
+      , network   >= 2.6 && < 3.2
    exposed-modules:
      PostgREST.Unix

@@ -154,7 +140,7 @@ executable postgrest
                      NoImplicitPrelude
  hs-source-dirs:     main
  main-is:            Main.hs
-  build-depends:      base                >= 4.9 && < 4.17
+  build-depends:      base                >= 4.9 && < 4.16
                    , containers          >= 0.5.7 && < 0.7
                    , postgrest
                    , protolude           >= 0.3.1 && < 0.4
@@ -179,88 +165,114 @@ test-suite spec
                      NoImplicitPrelude
  hs-source-dirs:     test/spec
  main-is:            Main.hs
-  other-modules:      Feature.Auth.AsymmetricJwtSpec
-                      Feature.Auth.AudienceJwtSecretSpec
-                      Feature.Auth.AuthSpec
-                      Feature.Auth.BinaryJwtSecretSpec
-                      Feature.Auth.NoAnonSpec
-                      Feature.Auth.NoJwtSpec
+  other-modules:      Feature.AndOrParamsSpec
+                      Feature.AsymmetricJwtSpec
+                      Feature.AudienceJwtSecretSpec
+                      Feature.AuthSpec
+                      Feature.BinaryJwtSecretSpec
                      Feature.ConcurrentSpec
                      Feature.CorsSpec
+                      Feature.DeleteSpec
+                      Feature.DisabledOpenApiSpec
+                      Feature.EmbedDisambiguationSpec
+                      Feature.EmbedInnerJoinSpec
                      Feature.ExtraSearchPathSpec
+                      Feature.HtmlRawOutputSpec
+                      Feature.InsertSpec
+                      Feature.IgnorePrivOpenApiSpec
+                      Feature.JsonOperatorSpec
                      Feature.LegacyGucsSpec
-                      Feature.NoSuperuserSpec
-                      Feature.ObservabilitySpec
-                      Feature.OpenApi.DisabledOpenApiSpec
-                      Feature.OpenApi.IgnorePrivOpenApiSpec
-                      Feature.OpenApi.OpenApiSpec
-                      Feature.OpenApi.ProxySpec
-                      Feature.OpenApi.RootSpec
-                      Feature.OpenApi.SecurityOpenApiSpec
+                      Feature.MultipleSchemaSpec
+                      Feature.NoJwtSpec
+                      Feature.NonexistentSchemaSpec
+                      Feature.OpenApiSpec
                      Feature.OptionsSpec
-                      Feature.Query.AndOrParamsSpec
-                      Feature.Query.ComputedRelsSpec
-                      Feature.Query.DeleteSpec
-                      Feature.Query.EmbedDisambiguationSpec
-                      Feature.Query.EmbedInnerJoinSpec
-                      Feature.Query.PlanSpec
-                      Feature.Query.HtmlRawOutputSpec
-                      Feature.Query.InsertSpec
-                      Feature.Query.JsonOperatorSpec
-                      Feature.Query.MultipleSchemaSpec
-                      Feature.Query.ErrorSpec
-                      Feature.Query.PgSafeUpdateSpec
-                      Feature.Query.PostGISSpec
-                      Feature.Query.QueryLimitedSpec
-                      Feature.Query.QuerySpec
-                      Feature.Query.RangeSpec
-                      Feature.Query.RawOutputTypesSpec
-                      Feature.Query.RelatedQueriesSpec
-                      Feature.Query.RpcSpec
-                      Feature.Query.SingularSpec
-                      Feature.Query.NullsStrip
-                      Feature.Query.SpreadQueriesSpec
-                      Feature.Query.UnicodeSpec
-                      Feature.Query.UpdateSpec
-                      Feature.Query.UpsertSpec
+                      Feature.ProxySpec
+                      Feature.QueryLimitedSpec
+                      Feature.QuerySpec
+                      Feature.RangeSpec
+                      Feature.RawOutputTypesSpec
                      Feature.RollbackSpec
+                      Feature.RootSpec
                      Feature.RpcPreRequestGucsSpec
+                      Feature.RpcSpec
+                      Feature.SingularSpec
+                      Feature.UnicodeSpec
+                      Feature.UpdateSpec
+                      Feature.UpsertSpec
                      SpecHelper
-  build-depends:      base              >= 4.9 && < 4.17
-                    , aeson             >= 2.0.3 && < 2.2
+                      TestTypes
+  build-depends:      base              >= 4.9 && < 4.16
+                    , aeson             >= 1.4.7 && < 1.6
                    , aeson-qq          >= 0.8.1 && < 0.9
                    , async             >= 2.1.1 && < 2.3
                    , auto-update       >= 0.1.4 && < 0.2
                    , base64-bytestring >= 1 && < 1.3
-                    , bytestring        >= 0.10.8 && < 0.12
+                    , bytestring        >= 0.10.8 && < 0.11
                    , case-insensitive  >= 1.2 && < 1.3
                    , containers        >= 0.5.7 && < 0.7
-                    , hasql-pool        >= 0.10 && < 0.11
+                    , hasql-pool        >= 0.5 && < 0.6
                    , hasql-transaction >= 1.0.1 && < 1.1
                    , heredoc           >= 0.2 && < 0.3
-                    , hspec             >= 2.3 && < 2.10
+                    , hspec             >= 2.3 && < 2.9
                    , hspec-wai         >= 0.10 && < 0.12
                    , hspec-wai-json    >= 0.10 && < 0.12
                    , http-types        >= 0.12.3 && < 0.13
-                    , lens              >= 4.14 && < 5.3
-                    , lens-aeson        >= 1.0.1 && < 1.3
+                    , lens              >= 4.14 && < 5.1
+                    , lens-aeson        >= 1.0.1 && < 1.2
                    , monad-control     >= 1.0.1 && < 1.1
                    , postgrest
                    , process           >= 1.4.2 && < 1.7
                    , protolude         >= 0.3.1 && < 0.4
                    , regex-tdfa        >= 1.2.2 && < 1.4
-                    , scientific        >= 0.3.4 && < 0.4
                    , text              >= 1.2.2 && < 1.3
                    , transformers-base >= 0.4.4 && < 0.5
                    , wai               >= 3.2.1 && < 3.3
                    , wai-extra         >= 3.0.19 && < 3.2
-  ghc-options:        -threaded -O0 -Werror -Wall -fwarn-identities
+  ghc-options:        -O0 -Werror -Wall -fwarn-identities
                      -fno-spec-constr -optP-Wno-nonportable-include-path
                      -fno-warn-missing-signatures
                      -fwrite-ide-info
                      -- https://github.com/PostgREST/postgrest/issues/387
                      -with-rtsopts=-K33K

+test-suite querycost
+  type:               exitcode-stdio-1.0
+  default-language:   Haskell2010
+  default-extensions: OverloadedStrings
+                      QuasiQuotes
+                      NoImplicitPrelude
+  hs-source-dirs:     test/spec
+  main-is:            QueryCost.hs
+  other-modules:      SpecHelper
+  build-depends:      base              >= 4.9 && < 4.16
+                    , aeson             >= 1.4.7 && < 1.6
+                    , base64-bytestring >= 1 && < 1.3
+                    , bytestring        >= 0.10.8 && < 0.11
+                    , case-insensitive  >= 1.2 && < 1.3
+                    , containers        >= 0.5.7 && < 0.7
+                    , contravariant     >= 1.4 && < 1.6
+                    , hasql             >= 1.4 && < 1.5
+                    , hasql-dynamic-statements  == 0.3.1
+                    , hasql-pool        >= 0.5 && < 0.6
+                    , hasql-transaction >= 1.0.1 && < 1.1
+                    , heredoc           >= 0.2 && < 0.3
+                    , hspec             >= 2.3 && < 2.9
+                    , hspec-wai         >= 0.10 && < 0.12
+                    , http-types        >= 0.12.3 && < 0.13
+                    , lens              >= 4.14 && < 5.1
+                    , lens-aeson        >= 1.0.1 && < 1.2
+                    , postgrest
+                    , process           >= 1.4.2 && < 1.7
+                    , protolude         >= 0.3.1 && < 0.4
+                    , regex-tdfa        >= 1.2.2 && < 1.4
+                    , wai-extra         >= 3.0.19 && < 3.2
+  ghc-options:        -O0 -Werror -Wall -fwarn-identities
+                      -fno-spec-constr -optP-Wno-nonportable-include-path
+                      -fwrite-ide-info
+                      -- https://github.com/PostgREST/postgrest/issues/387
+                      -with-rtsopts=-K1K
+
 test-suite doctests
  type:               exitcode-stdio-1.0
  default-language:   Haskell2010
@@ -268,7 +280,7 @@ test-suite doctests
                      NoImplicitPrelude
  hs-source-dirs:     test/doc
  main-is:            Main.hs
-  build-depends:      base              >= 4.9 && < 4.17
+  build-depends:      base              >= 4.9 && < 4.16
                    , doctest           >= 0.8
                    , postgrest
                    , pretty-simple
@@ -11,7 +11,7 @@
 }:
 let
  postgrest =
-    import ./default.nix { };
+    import ./default.nix;

  inherit (postgrest) pkgs;

@@ -40,23 +40,20 @@ lib.overrideDerivation postgrest.env (
        pkgs.cabal2nix
        pkgs.git
        pkgs.postgresql
-        pkgs.update-nix-fetchgit
        postgrest.hsie.bin
      ]
      ++ toolboxes;

    shellHook =
      ''
-        export HISTFILE=.history
-
-        source ${pkgs.bash-completion}/etc/profile.d/bash_completion.sh
+        source ${pkgs.bashCompletion}/etc/profile.d/bash_completion.sh
        source ${pkgs.git}/share/git/contrib/completion/git-completion.bash
-        source ${postgrest.hsie.bash-completion}
+        source ${postgrest.hsie.bashCompletion}

      ''
      + builtins.concatStringsSep "\n" (
-        builtins.map (bash-completion: "source ${bash-completion}") (
-          builtins.concatLists (builtins.map (toolbox: toolbox.bash-completion) toolboxes)
+        builtins.map (bashCompletion: "source ${bashCompletion}") (
+          builtins.concatLists (builtins.map (toolbox: toolbox.bashCompletion) toolboxes)
        )
      );
  }
@@ -1,87 +0,0 @@
-{-# LANGUAGE NamedFieldPuns  #-}
-{-# LANGUAGE RecordWildCards #-}
-
-module PostgREST.Admin
-  ( runAdmin
-  ) where
-
-import qualified Data.Text                 as T
-import qualified Hasql.Session             as SQL
-import qualified Network.HTTP.Types.Status as HTTP
-import qualified Network.Wai               as Wai
-import qualified Network.Wai.Handler.Warp  as Warp
-
-import Control.Monad.Extra (whenJust)
-
-import Network.Socket
-import Network.Socket.ByteString
-
-import PostgREST.AppState (AppState)
-import PostgREST.Config   (AppConfig (..))
-
-import qualified PostgREST.AppState as AppState
-
-import Protolude
-
-runAdmin :: AppConfig -> AppState -> Warp.Settings -> IO ()
-runAdmin conf@AppConfig{configAdminServerPort} appState settings =
-  whenJust configAdminServerPort $ \adminPort -> do
-    AppState.logWithZTime appState $ "Admin server listening on port " <> show adminPort
-    void . forkIO $ Warp.runSettings (settings & Warp.setPort adminPort) adminApp
-  where
-    adminApp = admin appState conf
-
-- | PostgREST admin application
-admin :: AppState.AppState -> AppConfig -> Wai.Application
-admin appState appConfig req respond  = do
-  isMainAppReachable  <- any isRight <$> reachMainApp appConfig
-  isSchemaCacheLoaded <- isJust <$> AppState.getSchemaCache appState
-  isConnectionUp      <-
-    if configDbChannelEnabled appConfig
-      then AppState.getIsListenerOn appState
-      else isRight <$> AppState.usePool appState (SQL.sql "SELECT 1")
-
-  case Wai.pathInfo req of
-    ["ready"] ->
-      respond $ Wai.responseLBS (if isMainAppReachable && isConnectionUp && isSchemaCacheLoaded then HTTP.status200 else HTTP.status503) [] mempty
-    ["live"] ->
-      respond $ Wai.responseLBS (if isMainAppReachable then HTTP.status200 else HTTP.status503) [] mempty
-    _ ->
-      respond $ Wai.responseLBS HTTP.status404 [] mempty
-
-- Try to connect to the main app socket
-- Note that it doesn't even send a valid HTTP request, we just want to check that the main app is accepting connections
-- The code for resolving the "*4", "!4", "*6", "!6", "*" special values is taken from
-- https://hackage.haskell.org/package/streaming-commons-0.2.2.4/docs/src/Data.Streaming.Network.html#bindPortGenEx
-reachMainApp :: AppConfig -> IO [Either IOException ()]
-reachMainApp AppConfig{..} =
-  case configServerUnixSocket of
-    Just path ->  do
-      sock <- socket AF_UNIX Stream 0
-      (:[]) <$> try (do
-        connect sock $ SockAddrUnix path
-        withSocketsDo $ bracket (pure sock) close sendEmpty)
-    Nothing -> do
-      let
-        host | configServerHost `elem` ["*4", "!4", "*6", "!6", "*"] = Nothing
-             | otherwise                                             = Just configServerHost
-        filterAddrs xs =
-          case configServerHost of
-              "*4" -> ipv4Addrs xs ++ ipv6Addrs xs
-              "!4" -> ipv4Addrs xs
-              "*6" -> ipv6Addrs xs ++ ipv4Addrs xs
-              "!6" -> ipv6Addrs xs
-              _    -> xs
-        ipv4Addrs = filter ((/=) AF_INET6 . addrFamily)
-        ipv6Addrs = filter ((==) AF_INET6 . addrFamily)
-
-      addrs <- getAddrInfo (Just $ defaultHints { addrSocketType = Stream }) (T.unpack <$> host) (Just . show $ configServerPort)
-      tryAddr `traverse` filterAddrs addrs
-  where
-    sendEmpty sock = void $ send sock mempty
-    tryAddr :: AddrInfo -> IO (Either IOException ())
-    tryAddr addr = do
-      sock <- socket (addrFamily addr) (addrSocketType addr) (addrProtocol addr)
-      try $ do
-        connect sock $ addrAddress addr
-        withSocketsDo $ bracket (pure sock) close sendEmpty
@@ -1,379 +0,0 @@
-{-|
-Module      : PostgREST.Request.ApiRequest
-Description : PostgREST functions to translate HTTP request to a domain type called ApiRequest.
-}
-{-# LANGUAGE LambdaCase      #-}
-{-# LANGUAGE MultiWayIf      #-}
-{-# LANGUAGE NamedFieldPuns  #-}
-{-# LANGUAGE RecordWildCards #-}
-
-module PostgREST.ApiRequest
-  ( ApiRequest(..)
-  , InvokeMethod(..)
-  , Mutation(..)
-  , MediaType(..)
-  , Action(..)
-  , Target(..)
-  , Payload(..)
-  , userApiRequest
-  ) where
-
-import qualified Data.Aeson            as JSON
-import qualified Data.Aeson.Key        as K
-import qualified Data.Aeson.KeyMap     as KM
-import qualified Data.ByteString.Char8 as BS
-import qualified Data.ByteString.Lazy  as LBS
-import qualified Data.CaseInsensitive  as CI
-import qualified Data.Csv              as CSV
-import qualified Data.HashMap.Strict   as HM
-import qualified Data.List             as L
-import qualified Data.List.NonEmpty    as NonEmptyList
-import qualified Data.Map.Strict       as M
-import qualified Data.Set              as S
-import qualified Data.Text.Encoding    as T
-import qualified Data.Vector           as V
-
-import Data.Either.Combinators (mapBoth)
-
-import Control.Arrow             ((***))
-import Data.Aeson.Types          (emptyArray, emptyObject)
-import Data.List                 (lookup, union)
-import Data.Ranged.Ranges        (emptyRange, rangeIntersection,
-                                  rangeIsEmpty)
-import Network.HTTP.Types.Header (RequestHeaders, hCookie)
-import Network.HTTP.Types.URI    (parseSimpleQuery)
-import Network.Wai               (Request (..))
-import Network.Wai.Parse         (parseHttpAccept)
-import Web.Cookie                (parseCookies)
-
-import PostgREST.ApiRequest.QueryParams  (QueryParams (..))
-import PostgREST.ApiRequest.Types        (ApiRequestError (..),
-                                          RangeError (..))
-import PostgREST.Config                  (AppConfig (..),
-                                          OpenAPIMode (..))
-import PostgREST.MediaType               (MTPlanFormat (..),
-                                          MediaType (..))
-import PostgREST.RangeQuery              (NonnegRange, allRange,
-                                          convertToLimitZeroRange,
-                                          hasLimitZero,
-                                          rangeRequested)
-import PostgREST.SchemaCache.Identifiers (FieldName,
-                                          QualifiedIdentifier (..),
-                                          Schema)
-
-import qualified PostgREST.ApiRequest.Preferences as Preferences
-import qualified PostgREST.ApiRequest.QueryParams as QueryParams
-import qualified PostgREST.MediaType              as MediaType
-
-import Protolude
-
-
-type RequestBody = LBS.ByteString
-
-data Payload
-  = ProcessedJSON -- ^ Cached attributes of a JSON payload
-      { payRaw  :: LBS.ByteString
-      -- ^ This is the raw ByteString that comes from the request body.  We
-      -- cache this instead of an Aeson Value because it was detected that for
-      -- large payloads the encoding had high memory usage, see
-      -- https://github.com/PostgREST/postgrest/pull/1005 for more details
-      , payKeys :: S.Set Text
-      -- ^ Keys of the object or if it's an array these keys are guaranteed to
-      -- be the same across all its objects
-      }
-  | ProcessedUrlEncoded { payArray  :: [(Text, Text)], payKeys :: S.Set Text }
-  | RawJSON { payRaw  :: LBS.ByteString }
-  | RawPay  { payRaw  :: LBS.ByteString }
-
-data InvokeMethod = InvHead | InvGet | InvPost deriving Eq
-data Mutation = MutationCreate | MutationDelete | MutationSingleUpsert | MutationUpdate deriving Eq
-
-- | Types of things a user wants to do to tables/views/procs
-data Action
-  = ActionMutate Mutation
-  | ActionRead {isHead :: Bool}
-  | ActionInvoke InvokeMethod
-  | ActionInfo
-  | ActionInspect {isHead :: Bool}
-  deriving Eq
-- | The path info that will be mapped to a target (used to handle validations and errors before defining the Target)
-data PathInfo
-  = PathInfo
-      { pathName       :: Text
-      , pathIsProc     :: Bool
-      , pathIsDefSpec  :: Bool
-      , pathIsRootSpec :: Bool
-      }
-- | The target db object of a user action
-data Target = TargetIdent QualifiedIdentifier
-            | TargetProc{tProc :: QualifiedIdentifier, tpIsRootSpec :: Bool}
-            | TargetDefaultSpec{tdsSchema :: Schema} -- The default spec offered at root "/"
-
-{-|
-  Describes what the user wants to do. This data type is a
-  translation of the raw elements of an HTTP request into domain
-  specific language.  There is no guarantee that the intent is
-  sensible, it is up to a later stage of processing to determine
-  if it is an action we are able to perform.
-}
-data ApiRequest = ApiRequest {
-    iAction              :: Action                           -- ^ Similar but not identical to HTTP method, e.g. Create/Invoke both POST
-  , iRange               :: HM.HashMap Text NonnegRange      -- ^ Requested range of rows within response
-  , iTopLevelRange       :: NonnegRange                      -- ^ Requested range of rows from the top level
-  , iTarget              :: Target                           -- ^ The target, be it calling a proc or accessing a table
-  , iPayload             :: Maybe Payload                    -- ^ Data sent by client and used for mutation actions
-  , iPreferences         :: Preferences.Preferences          -- ^ Prefer header values
-  , iQueryParams         :: QueryParams.QueryParams
-  , iColumns             :: S.Set FieldName                  -- ^ parsed colums from &columns parameter and payload
-  , iHeaders             :: [(ByteString, ByteString)]       -- ^ HTTP request headers
-  , iCookies             :: [(ByteString, ByteString)]       -- ^ Request Cookies
-  , iPath                :: ByteString                       -- ^ Raw request path
-  , iMethod              :: ByteString                       -- ^ Raw request method
-  , iSchema              :: Schema                           -- ^ The request schema. Can vary depending on profile headers.
-  , iNegotiatedByProfile :: Bool                             -- ^ If schema was was chosen according to the profile spec https://www.w3.org/TR/dx-prof-conneg/
-  , iAcceptMediaType     :: MediaType                        -- ^ The media type in the Accept header
-  , iContentMediaType    :: MediaType                        -- ^ The media type in the Content-Type header
-  }
-
-- | Examines HTTP request and translates it into user intent.
-userApiRequest :: AppConfig -> Request -> RequestBody -> Either ApiRequestError ApiRequest
-userApiRequest conf req reqBody = do
-  pInfo@PathInfo{..} <- getPathInfo conf $ pathInfo req
-  act <- getAction pInfo method
-  qPrms <- first QueryParamError $ QueryParams.parse (pathIsProc && act `elem` [ActionInvoke InvGet, ActionInvoke InvHead]) $ rawQueryString req
-  (acceptMediaType, contentMediaType) <- getMediaTypes conf hdrs act pInfo
-  (schema, negotiatedByProfile) <- getSchema conf hdrs method
-  (topLevelRange, ranges) <- getRanges method qPrms hdrs
-  (payload, columns) <- getPayload reqBody contentMediaType qPrms act pInfo
-  return $ ApiRequest {
-    iAction = act
-  , iTarget = if | pathIsProc    -> TargetProc (QualifiedIdentifier schema pathName) pathIsRootSpec
-                 | pathIsDefSpec -> TargetDefaultSpec schema
-                 | otherwise     -> TargetIdent $ QualifiedIdentifier schema pathName
-  , iRange = ranges
-  , iTopLevelRange = topLevelRange
-  , iPayload = payload
-  , iPreferences = Preferences.fromHeaders (configDbTxAllowOverride conf) hdrs
-  , iQueryParams = qPrms
-  , iColumns = columns
-  , iHeaders = iHdrs
-  , iCookies = iCkies
-  , iPath = rawPathInfo req
-  , iMethod = method
-  , iSchema = schema
-  , iNegotiatedByProfile = negotiatedByProfile
-  , iAcceptMediaType = acceptMediaType
-  , iContentMediaType = contentMediaType
-  }
-  where
-    method = requestMethod req
-    hdrs = requestHeaders req
-    lookupHeader    = flip lookup hdrs
-    iHdrs = [ (CI.foldedCase k, v) | (k,v) <- hdrs, k /= hCookie]
-    iCkies = maybe [] parseCookies $ lookupHeader "Cookie"
-
-getPathInfo :: AppConfig -> [Text] -> Either ApiRequestError PathInfo
-getPathInfo AppConfig{configOpenApiMode, configDbRootSpec} path =
-  case path of
-    []             -> case configDbRootSpec of
-                        Just (QualifiedIdentifier _ pathName)     -> Right $ PathInfo pathName True False True
-                        Nothing | configOpenApiMode == OADisabled -> Left NotFound
-                                | otherwise                       -> Right $ PathInfo mempty False True False
-    [table]        -> Right $ PathInfo table False False False
-    ["rpc", pName] -> Right $ PathInfo pName True False False
-    _              -> Left NotFound
-
-getAction :: PathInfo -> ByteString -> Either ApiRequestError Action
-getAction PathInfo{pathIsProc, pathIsDefSpec} method =
-  if pathIsProc && method `notElem` ["HEAD", "GET", "POST", "OPTIONS"]
-    then Left $ InvalidRpcMethod method
-    else case method of
-      -- The HEAD method is identical to GET except that the server MUST NOT return a message-body in the response
-      -- From https://www.w3.org/Protocols/rfc2616/rfc2616-sec9.html#sec9.4
-      "HEAD"     | pathIsDefSpec -> Right $ ActionInspect{isHead=True}
-                 | pathIsProc    -> Right $ ActionInvoke InvHead
-                 | otherwise     -> Right $ ActionRead{isHead=True}
-      "GET"      | pathIsDefSpec -> Right $ ActionInspect{isHead=False}
-                 | pathIsProc    -> Right $ ActionInvoke InvGet
-                 | otherwise     -> Right $ ActionRead{isHead=False}
-      "POST"     | pathIsProc    -> Right $ ActionInvoke InvPost
-                 | otherwise     -> Right $ ActionMutate MutationCreate
-      "PATCH"                    -> Right $ ActionMutate MutationUpdate
-      "PUT"                      -> Right $ ActionMutate MutationSingleUpsert
-      "DELETE"                   -> Right $ ActionMutate MutationDelete
-      "OPTIONS"                  -> Right ActionInfo
-      _                          -> Left $ UnsupportedMethod method
-
-getMediaTypes :: AppConfig -> RequestHeaders -> Action -> PathInfo -> Either ApiRequestError (MediaType, MediaType)
-getMediaTypes conf hdrs action path = do
-   acceptMediaType <- negotiateContent conf action path accepts
-   pure (acceptMediaType, contentMediaType)
-  where
-    accepts = maybe [MTAny] (map MediaType.decodeMediaType . parseHttpAccept) $ lookupHeader "accept"
-    contentMediaType = maybe MTApplicationJSON MediaType.decodeMediaType $ lookupHeader "content-type"
-    lookupHeader    = flip lookup hdrs
-
-getSchema :: AppConfig -> RequestHeaders -> ByteString -> Either ApiRequestError (Schema, Bool)
-getSchema AppConfig{configDbSchemas} hdrs method = do
-  case profile of
-    Just p | p `notElem` configDbSchemas -> Left $ UnacceptableSchema $ toList configDbSchemas
-           | otherwise                   -> Right (p, True)
-    Nothing -> Right (defaultSchema, length configDbSchemas /= 1) -- if we have many schemas, assume the default schema was negotiated
-  where
-    defaultSchema = NonEmptyList.head configDbSchemas
-    profile = case method of
-      -- POST/PATCH/PUT/DELETE don't use the same header as per the spec
-      "DELETE" -> contentProfile
-      "PATCH"  -> contentProfile
-      "POST"   -> contentProfile
-      "PUT"    -> contentProfile
-      _        -> acceptProfile
-    contentProfile = T.decodeUtf8 <$> lookupHeader "Content-Profile"
-    acceptProfile = T.decodeUtf8 <$> lookupHeader "Accept-Profile"
-    lookupHeader    = flip lookup hdrs
-
-getRanges :: ByteString -> QueryParams -> RequestHeaders -> Either ApiRequestError (NonnegRange, HM.HashMap Text NonnegRange)
-getRanges method QueryParams{qsOrder,qsRanges} hdrs
-  | isInvalidRange = Left $ InvalidRange (if rangeIsEmpty headerRange then LowerGTUpper else NegativeLimit)
-  | method `elem` ["PATCH", "DELETE"] && not (null qsRanges) && null qsOrder = Left LimitNoOrderError
-  | method == "PUT" && topLevelRange /= allRange = Left PutLimitNotAllowedError
-  | otherwise = Right (topLevelRange, ranges)
-  where
-    -- According to the RFC (https://www.rfc-editor.org/rfc/rfc9110.html#name-range),
-    -- the Range header must be ignored for all methods other than GET
-    headerRange = if method == "GET" then rangeRequested hdrs else allRange
-    limitRange = fromMaybe allRange (HM.lookup "limit" qsRanges)
-    headerAndLimitRange = rangeIntersection headerRange limitRange
-    -- Bypass all the ranges and send only the limit zero range (0 <= x <= -1) if
-    -- limit=0 is present in the query params (not allowed for the Range header)
-    ranges = HM.insert "limit" (convertToLimitZeroRange limitRange headerAndLimitRange) qsRanges
-    -- The only emptyRange allowed is the limit zero range
-    isInvalidRange = topLevelRange == emptyRange && not (hasLimitZero limitRange)
-    topLevelRange = fromMaybe allRange $ HM.lookup "limit" ranges -- if no limit is specified, get all the request rows
-
-getPayload :: RequestBody -> MediaType -> QueryParams.QueryParams -> Action -> PathInfo -> Either ApiRequestError (Maybe Payload, S.Set FieldName)
-getPayload reqBody contentMediaType QueryParams{qsColumns} action PathInfo{pathIsProc}= do
-  checkedPayload <- if shouldParsePayload then payload else Right Nothing
-  let cols = case (checkedPayload, columns) of
-        (Just ProcessedJSON{payKeys}, _)       -> payKeys
-        (Just ProcessedUrlEncoded{payKeys}, _) -> payKeys
-        (Just RawJSON{}, Just cls)             -> cls
-        _                                      -> S.empty
-  return (checkedPayload, cols)
-  where
-    payload :: Either ApiRequestError (Maybe Payload)
-    payload = mapBoth InvalidBody Just $ case (contentMediaType, pathIsProc) of
-      (MTApplicationJSON, _) ->
-        if isJust columns
-          then Right $ RawJSON reqBody
-          else note "All object keys must match" . payloadAttributes reqBody
-                 =<< if LBS.null reqBody && pathIsProc
-                       then Right emptyObject
-                       else first BS.pack $ JSON.eitherDecode reqBody
-      (MTTextCSV, _) -> do
-        json <- csvToJson <$> first BS.pack (CSV.decodeByName reqBody)
-        note "All lines must have same number of fields" $ payloadAttributes (JSON.encode json) json
-      (MTUrlEncoded, isProc) -> do
-        let params = (T.decodeUtf8 *** T.decodeUtf8) <$> parseSimpleQuery (LBS.toStrict reqBody)
-        if isProc
-          then Right $ ProcessedUrlEncoded params (S.fromList $ fst <$> params)
-          else
-            let paramsMap = HM.fromList $ (identity *** JSON.String) <$> params in
-            Right $ ProcessedJSON (JSON.encode paramsMap) $ S.fromList (HM.keys paramsMap)
-      (MTTextPlain, True) -> Right $ RawPay reqBody
-      (MTTextXML, True) -> Right $ RawPay reqBody
-      (MTOctetStream, True) -> Right $ RawPay reqBody
-      (ct, _) -> Left $ "Content-Type not acceptable: " <> MediaType.toMime ct
-
-    shouldParsePayload = case (action, contentMediaType) of
-      (ActionMutate MutationCreate, _)       -> True
-      (ActionInvoke InvPost, _)              -> True
-      (ActionMutate MutationSingleUpsert, _) -> True
-      (ActionMutate MutationUpdate, _)       -> True
-      _                                      -> False
-
-    columns = case action of
-      ActionMutate MutationCreate -> qsColumns
-      ActionMutate MutationUpdate -> qsColumns
-      ActionInvoke InvPost        -> qsColumns
-      _                           -> Nothing
-
-type CsvData = V.Vector (M.Map Text LBS.ByteString)
-
-{-|
-  Converts CSV like
-  a,b
-  1,hi
-  2,bye
-
-  into a JSON array like
-  [ {"a": "1", "b": "hi"}, {"a": 2, "b": "bye"} ]
-
-  The reason for its odd signature is so that it can compose
-  directly with CSV.decodeByName
-}
-csvToJson :: (CSV.Header, CsvData) -> JSON.Value
-csvToJson (_, vals) =
-  JSON.Array $ V.map rowToJsonObj vals
- where
-  rowToJsonObj = JSON.Object . KM.fromMapText .
-    M.map (\str ->
-        if str == "NULL"
-          then JSON.Null
-          else JSON.String . T.decodeUtf8 $ LBS.toStrict str
-      )
-
-payloadAttributes :: RequestBody -> JSON.Value -> Maybe Payload
-payloadAttributes raw json =
-  -- Test that Array contains only Objects having the same keys
-  case json of
-    JSON.Array arr ->
-      case arr V.!? 0 of
-        Just (JSON.Object o) ->
-          let canonicalKeys = S.fromList $ K.toText <$> KM.keys o
-              areKeysUniform = all (\case
-                JSON.Object x -> S.fromList (K.toText <$> KM.keys x) == canonicalKeys
-                _ -> False) arr in
-          if areKeysUniform
-            then Just $ ProcessedJSON raw canonicalKeys
-            else Nothing
-        Just _ -> Nothing
-        Nothing -> Just emptyPJArray
-
-    JSON.Object o -> Just $ ProcessedJSON raw (S.fromList $ K.toText <$> KM.keys o)
-
-    -- truncate everything else to an empty array.
-    _ -> Just emptyPJArray
-  where
-    emptyPJArray = ProcessedJSON (JSON.encode emptyArray) S.empty
-
-
-- | Do content negotiation. i.e. choose a media type based on the intersection of accepted/produced media types.
-negotiateContent :: AppConfig -> Action -> PathInfo -> [MediaType] -> Either ApiRequestError MediaType
-negotiateContent conf action path accepts =
-  case firstAcceptedPick of
-    Just MTAny -> Right MTApplicationJSON -- by default(for */*) we respond with json
-    Just mt    -> Right mt
-    Nothing    -> Left . MediaTypeError $ map MediaType.toMime accepts
-  where
-    -- if there are multiple accepted media types, pick the first
-    firstAcceptedPick = listToMaybe $ L.intersect accepts $ producedMediaTypes conf action path
-
-producedMediaTypes :: AppConfig -> Action -> PathInfo -> [MediaType]
-producedMediaTypes conf action path =
-  case action of
-    ActionRead _    -> defaultMediaTypes ++ rawMediaTypes
-    ActionInvoke _  -> invokeMediaTypes
-    ActionInfo      -> defaultMediaTypes
-    ActionMutate _  -> defaultMediaTypes
-    ActionInspect _ -> inspectMediaTypes
-  where
-    inspectMediaTypes = [MTOpenAPI, MTApplicationJSON, MTArrayJSONStrip, MTAny]
-    invokeMediaTypes =
-      defaultMediaTypes
-        ++ rawMediaTypes
-        ++ [MTOpenAPI | pathIsRootSpec path]
-    defaultMediaTypes =
-      [MTApplicationJSON, MTArrayJSONStrip, MTSingularJSON True, MTSingularJSON False, MTGeoJSON, MTTextCSV] ++
-      [MTPlan MTApplicationJSON PlanText mempty | configDbPlanEnabled conf] ++ [MTAny]
-    rawMediaTypes = configRawMediaTypes conf `union` [MTOctetStream, MTTextPlain, MTTextXML]
@@ -1,813 +0,0 @@
-- |
-- Module      : PostgREST.ApiRequest.QueryParams
-- Description : Parser for PostgREST Query parameters
--
-- This module is in charge of parsing all the querystring values in an url, e.g.
-- the select, id, order in `/projects?select=id,name&id=eq.1&order=id,name.desc`.
-{-# LANGUAGE LambdaCase    #-}
-{-# LANGUAGE TupleSections #-}
-module PostgREST.ApiRequest.QueryParams
-  ( parse
-  , QueryParams(..)
-  , pRequestRange
-  ) where
-
-import qualified Data.ByteString.Char8         as BS
-import qualified Data.HashMap.Strict           as HM
-import qualified Data.List                     as L
-import qualified Data.Set                      as S
-import qualified Data.Text                     as T
-import qualified Data.Text.Encoding            as T
-import qualified Network.HTTP.Base             as HTTP
-import qualified Network.HTTP.Types.URI        as HTTP
-import qualified Text.ParserCombinators.Parsec as P
-
-import Control.Arrow                 ((***))
-import Data.Either.Combinators       (mapLeft)
-import Data.List                     (init, last)
-import Data.Ranged.Boundaries        (Boundary (..))
-import Data.Ranged.Ranges            (Range (..))
-import Data.Tree                     (Tree (..))
-import Text.Parsec.Error             (errorMessages,
-                                      showErrorMessages)
-import Text.ParserCombinators.Parsec (GenParser, ParseError, Parser,
-                                      anyChar, between, char, digit,
-                                      eof, errorPos, letter,
-                                      lookAhead, many1, noneOf,
-                                      notFollowedBy, oneOf,
-                                      optionMaybe, sepBy, sepBy1,
-                                      string, try, (<?>))
-
-import PostgREST.RangeQuery              (NonnegRange, allRange,
-                                          rangeGeq, rangeLimit,
-                                          rangeOffset, restrictRange)
-import PostgREST.SchemaCache.Identifiers (FieldName)
-
-import PostgREST.ApiRequest.Types (EmbedParam (..), EmbedPath, Field,
-                                   Filter (..), FtsOperator (..),
-                                   Hint, JoinType (..),
-                                   JsonOperand (..),
-                                   JsonOperation (..), JsonPath,
-                                   ListVal, LogicOperator (..),
-                                   LogicTree (..), OpExpr (..),
-                                   OpQuantifier (..), Operation (..),
-                                   OrderDirection (..),
-                                   OrderNulls (..), OrderTerm (..),
-                                   QPError (..), QuantOperator (..),
-                                   SelectItem (..),
-                                   SimpleOperator (..), SingleVal,
-                                   TrileanVal (..))
-
-import Protolude hiding (try)
-
-data QueryParams =
-  QueryParams
-    { qsCanonical      :: ByteString
-    -- ^ Canonical representation of the query params, sorted alphabetically
-    , qsParams         :: [(Text, Text)]
-    -- ^ Parameters for RPC calls
-    , qsRanges         :: HM.HashMap Text (Range Integer)
-    -- ^ Ranges derived from &limit and &offset params
-    , qsOrder          :: [(EmbedPath, [OrderTerm])]
-    -- ^ &order parameters for each level
-    , qsLogic          :: [(EmbedPath, LogicTree)]
-    -- ^ &and and &or parameters used for complex boolean logic
-    , qsColumns        :: Maybe (S.Set FieldName)
-    -- ^ &columns parameter and payload
-    , qsSelect         :: [Tree SelectItem]
-    -- ^ &select parameter used to shape the response
-    , qsFilters        :: [(EmbedPath, Filter)]
-    -- ^ Filters on the result from e.g. &id=e.10
-    , qsFiltersRoot    :: [Filter]
-    -- ^ Subset of the filters that apply on the root table. These are used on UPDATE/DELETE.
-    , qsFiltersNotRoot :: [(EmbedPath, Filter)]
-    -- ^ Subset of the filters that do not apply on the root table
-    , qsFilterFields   :: S.Set FieldName
-    -- ^ Set of fields that filters apply to
-    , qsOnConflict     :: Maybe [FieldName]
-    -- ^ &on_conflict parameter used to upsert on specific unique keys
-    }
-
-- |
-- Parse query parameters from a query string like "id=eq.1&select=name".
--
-- The canonical representation of the query string has parameters sorted alphabetically:
--
-- >>> qsCanonical <$> parse True "a=1&c=3&b=2&d"
-- Right "a=1&b=2&c=3&d="
--
-- 'select' is a reserved parameter that selects the fields to be returned:
--
-- >>> qsSelect <$> parse False "select=name,location"
-- Right [Node {rootLabel = SelectField {selField = ("name",[]), selCast = Nothing, selAlias = Nothing}, subForest = []},Node {rootLabel = SelectField {selField = ("location",[]), selCast = Nothing, selAlias = Nothing}, subForest = []}]
--
-- Filters are parameters whose value contains an operator, separated by a '.' from its value:
--
-- >>> qsFilters <$> parse False "a.b=eq.0"
-- Right [(["a"],Filter {field = ("b",[]), opExpr = OpExpr False (OpQuant OpEqual Nothing "0")})]
--
-- If the operator specified in a filter does not exist, parsing the query string fails:
--
-- >>> qsFilters <$> parse False "a.b=noop.0"
-- Left (QPError "\"failed to parse filter (noop.0)\" (line 1, column 1)" "unexpected \"o\" expecting \"not\" or operator (eq, gt, ...)")
-parse :: Bool -> ByteString -> Either QPError QueryParams
-parse isRpcGet qs = do
-  rOrd                      <- pRequestOrder `traverse` order
-  rLogic                    <- pRequestLogicTree `traverse` logic
-  rCols                     <- pRequestColumns columns
-  rSel                      <- pRequestSelect select
-  (rFlts, params)           <- L.partition hasOp <$> pRequestFilter isRpcGet `traverse` filters
-  (rFltsRoot, rFltsNotRoot) <- pure $ L.partition hasRootFilter rFlts
-  rOnConflict               <- pRequestOnConflict `traverse` onConflict
-
-  let rFltsFields           = S.fromList (fst <$> filters)
-      params'               = mapMaybe (\case {(_, Filter (fld, _) (NoOpExpr v)) -> Just (fld,v); _ -> Nothing}) params
-      rFltsRoot'            = snd <$> rFltsRoot
-
-  return $ QueryParams canonical params' ranges rOrd rLogic rCols rSel rFlts rFltsRoot' rFltsNotRoot rFltsFields rOnConflict
-  where
-    hasRootFilter, hasOp :: (EmbedPath, Filter) -> Bool
-    hasRootFilter ([], _) = True
-    hasRootFilter _       = False
-    hasOp (_, Filter (_, _) (NoOpExpr _)) = False
-    hasOp _                               = True
-
-    logic = filter (endingIn ["and", "or"] . fst) nonemptyParams
-    select = fromMaybe "*" $ lookupParam "select"
-    onConflict = lookupParam "on_conflict"
-    columns = lookupParam "columns"
-    order = filter (endingIn ["order"] . fst) nonemptyParams
-    limits = filter (endingIn ["limit"] . fst) nonemptyParams
-    -- Replace .offset ending with .limit to be able to match those params later in a map
-    offsets = first (replaceLast "limit") <$> filter (endingIn ["offset"] . fst) nonemptyParams
-    lookupParam :: Text -> Maybe Text
-    lookupParam needle = toS <$> join (L.lookup needle qParams)
-    nonemptyParams = mapMaybe (\(k, v) -> (k,) <$> v) qParams
-
-    qString = HTTP.parseQueryReplacePlus True qs
-
-    qParams = [(T.decodeUtf8 k, T.decodeUtf8 <$> v)|(k,v) <- qString]
-
-    canonical =
-      BS.pack $ HTTP.urlEncodeVars
-        . L.sortOn fst
-        . map (join (***) BS.unpack . second (fromMaybe mempty))
-        $ qString
-
-    endingIn:: [Text] -> Text -> Bool
-    endingIn xx key = lastWord `elem` xx
-      where lastWord = L.last $ T.split (== '.') key
-
-    filters = filter (isFilter . fst) nonemptyParams
-    isFilter k = not (endingIn reservedEmbeddable k) && notElem k reserved
-    reserved = ["select", "columns", "on_conflict"]
-    reservedEmbeddable = ["order", "limit", "offset", "and", "or"]
-
-    replaceLast x s = T.intercalate "." $ L.init (T.split (=='.') s) <> [x]
-
-    ranges :: HM.HashMap Text (Range Integer)
-    ranges = HM.unionWith f limitParams offsetParams
-      where
-        f rl ro = Range (BoundaryBelow o) (BoundaryAbove $ o + l - 1)
-          where
-            l = fromMaybe 0 $ rangeLimit rl
-            o = rangeOffset ro
-
-        limitParams =
-          HM.fromList [(k, restrictRange (readMaybe v) allRange) | (k,v) <- limits]
-
-        offsetParams =
-          HM.fromList [(k, maybe allRange rangeGeq (readMaybe v)) | (k,v) <- offsets]
-
-simpleOperator :: Parser SimpleOperator
-simpleOperator =
-  try (string "neq" $> OpNotEqual) <|>
-  try (string "cs" $> OpContains) <|>
-  try (string "cd" $> OpContained) <|>
-  try (string "ov" $> OpOverlap) <|>
-  try (string "sl" $> OpStrictlyLeft) <|>
-  try (string "sr" $> OpStrictlyRight) <|>
-  try (string "nxr" $> OpNotExtendsRight) <|>
-  try (string "nxl" $> OpNotExtendsLeft) <|>
-  try (string "adj" $> OpAdjacent) <?>
-  "unknown single value operator"
-
-quantOperator :: Parser QuantOperator
-quantOperator =
-  try (string "eq" $> OpEqual) <|>
-  try (string "gte" $> OpGreaterThanEqual) <|>
-  try (string "gt" $> OpGreaterThan) <|>
-  try (string "lte" $> OpLessThanEqual) <|>
-  try (string "lt" $> OpLessThan) <|>
-  try (string "like" $> OpLike) <|>
-  try (string "ilike" $> OpILike) <|>
-  try (string "match" $> OpMatch) <|>
-  try (string "imatch" $> OpIMatch) <?>
-  "unknown single value operator"
-
-pRequestSelect :: Text -> Either QPError [Tree SelectItem]
-pRequestSelect selStr =
-  mapError $ P.parse pFieldForest ("failed to parse select parameter (" <> toS selStr <> ")") (toS selStr)
-
-pRequestOnConflict :: Text -> Either QPError [FieldName]
-pRequestOnConflict oncStr =
-  mapError $ P.parse pColumns ("failed to parse on_conflict parameter (" <> toS oncStr <> ")") (toS oncStr)
-
-- |
-- Parse `id=eq.1`(id, eq.1) into (EmbedPath, Filter)
--
-- >>> pRequestFilter False ("id", "eq.1")
-- Right ([],Filter {field = ("id",[]), opExpr = OpExpr False (OpQuant OpEqual Nothing "1")})
--
-- >>> pRequestFilter False ("id", "val")
-- Left (QPError "\"failed to parse filter (val)\" (line 1, column 1)" "unexpected \"v\" expecting \"not\" or operator (eq, gt, ...)")
--
-- >>> pRequestFilter True ("id", "val")
-- Right ([],Filter {field = ("id",[]), opExpr = NoOpExpr "val"})
-pRequestFilter :: Bool -> (Text, Text) -> Either QPError (EmbedPath, Filter)
-pRequestFilter isRpcGet (k, v) = mapError $ (,) <$> path <*> (Filter <$> fld <*> oper)
-  where
-    treePath = P.parse pTreePath ("failed to parse tree path (" ++ toS k ++ ")") $ toS k
-    oper = P.parse parseFlt ("failed to parse filter (" ++ toS v ++ ")") $ toS v
-    parseFlt = if isRpcGet
-      then pOpExpr pSingleVal <|> pure (NoOpExpr v)
-      else pOpExpr pSingleVal
-    path = fst <$> treePath
-    fld = snd <$> treePath
-
-pRequestOrder :: (Text, Text) -> Either QPError (EmbedPath, [OrderTerm])
-pRequestOrder (k, v) = mapError $ (,) <$> path <*> ord'
-  where
-    treePath = P.parse pTreePath ("failed to parse tree path (" ++ toS k ++ ")") $ toS k
-    path = fst <$> treePath
-    ord' = P.parse pOrder ("failed to parse order (" ++ toS v ++ ")") $ toS v
-
-pRequestRange :: (Text, NonnegRange) -> Either QPError (EmbedPath, NonnegRange)
-pRequestRange (k, v) = mapError $ (,) <$> path <*> pure v
-  where
-    treePath = P.parse pTreePath ("failed to parse tree path (" ++ toS k ++ ")") $ toS k
-    path = fst <$> treePath
-
-pRequestLogicTree :: (Text, Text) -> Either QPError (EmbedPath, LogicTree)
-pRequestLogicTree (k, v) = mapError $ (,) <$> embedPath <*> logicTree
-  where
-    path = P.parse pLogicPath ("failed to parse logic path (" ++ toS k ++ ")") $ toS k
-    embedPath = fst <$> path
-    logicTree = do
-      op <- snd <$> path
-      -- Concat op and v to make pLogicTree argument regular,
-      -- in the form of "?and=and(.. , ..)" instead of "?and=(.. , ..)"
-      P.parse pLogicTree ("failed to parse logic tree (" ++ toS v ++ ")") $ toS (op <> v)
-
-pRequestColumns :: Maybe Text -> Either QPError (Maybe (S.Set FieldName))
-pRequestColumns colStr =
-  case colStr of
-    Just str ->
-      mapError $ Just . S.fromList <$> P.parse pColumns ("failed to parse columns parameter (" <> toS str <> ")") (toS str)
-    _ -> Right Nothing
-
-ws :: Parser Text
-ws = toS <$> many (oneOf " \t")
-
-lexeme :: Parser a -> Parser a
-lexeme p = ws *> p <* ws
-
-pTreePath :: Parser (EmbedPath, Field)
-pTreePath = do
-  p <- pFieldName `sepBy1` pDelimiter
-  jp <- P.option [] pJsonPath
-  return (init p, (last p, jp))
-
-- |
-- Parse select= into a Forest of SelectItems
--
-- >>> P.parse pFieldForest "" "id"
-- Right [Node {rootLabel = SelectField {selField = ("id",[]), selCast = Nothing, selAlias = Nothing}, subForest = []}]
--
-- >>> P.parse pFieldForest "" "client(id)"
-- Right [Node {rootLabel = SelectRelation {selRelation = "client", selAlias = Nothing, selHint = Nothing, selJoinType = Nothing}, subForest = [Node {rootLabel = SelectField {selField = ("id",[]), selCast = Nothing, selAlias = Nothing}, subForest = []}]}]
--
-- >>> P.parse pFieldForest "" "*,client(*,nested(*))"
-- Right [Node {rootLabel = SelectField {selField = ("*",[]), selCast = Nothing, selAlias = Nothing}, subForest = []},Node {rootLabel = SelectRelation {selRelation = "client", selAlias = Nothing, selHint = Nothing, selJoinType = Nothing}, subForest = [Node {rootLabel = SelectField {selField = ("*",[]), selCast = Nothing, selAlias = Nothing}, subForest = []},Node {rootLabel = SelectRelation {selRelation = "nested", selAlias = Nothing, selHint = Nothing, selJoinType = Nothing}, subForest = [Node {rootLabel = SelectField {selField = ("*",[]), selCast = Nothing, selAlias = Nothing}, subForest = []}]}]}]
--
-- >>> P.parse pFieldForest "" "*,...client(*),other(*)"
-- Right [Node {rootLabel = SelectField {selField = ("*",[]), selCast = Nothing, selAlias = Nothing}, subForest = []},Node {rootLabel = SpreadRelation {selRelation = "client", selHint = Nothing, selJoinType = Nothing}, subForest = [Node {rootLabel = SelectField {selField = ("*",[]), selCast = Nothing, selAlias = Nothing}, subForest = []}]},Node {rootLabel = SelectRelation {selRelation = "other", selAlias = Nothing, selHint = Nothing, selJoinType = Nothing}, subForest = [Node {rootLabel = SelectField {selField = ("*",[]), selCast = Nothing, selAlias = Nothing}, subForest = []}]}]
--
-- >>> P.parse pFieldForest "" ""
-- Right []
--
-- >>> P.parse pFieldForest "" "id,clients(name[])"
-- Left (line 1, column 16):
-- unexpected '['
-- expecting letter, digit, "-", "->>", "->", "::", ")", "," or end of input
--
-- >>> P.parse pFieldForest "" "data->>-78xy"
-- Left (line 1, column 11):
-- unexpected 'x'
-- expecting digit, "->", "::", ".", "," or end of input
-pFieldForest :: Parser [Tree SelectItem]
-pFieldForest = pFieldTree `sepBy` lexeme (char ',')
-  where
-    pFieldTree =  Node <$> try pSpreadRelationSelect <*> between (char '(') (char ')') pFieldForest <|>
-                  Node <$> try pRelationSelect       <*> between (char '(') (char ')') pFieldForest <|>
-                  Node <$> pFieldSelect <*> pure []
-
-- |
-- Parse field names
--
-- >>> P.parse pFieldName "" "identifier"
-- Right "identifier"
--
-- >>> P.parse pFieldName "" "identifier with spaces"
-- Right "identifier with spaces"
--
-- >>> P.parse pFieldName "" "identifier-with-dashes"
-- Right "identifier-with-dashes"
--
-- >>> P.parse pFieldName "" "123"
-- Right "123"
--
-- >>> P.parse pFieldName "" "_"
-- Right "_"
--
-- >>> P.parse pFieldName "" "$"
-- Right "$"
--
-- >>> P.parse pFieldName "" ":"
-- Left (line 1, column 1):
-- unexpected ":"
-- expecting field name (* or [a..z0..9_$])
--
-- >>> P.parse pFieldName "" "\":\""
-- Right ":"
--
-- >>> P.parse pFieldName "" " no leading or trailing spaces "
-- Right "no leading or trailing spaces"
--
-- >>> P.parse pFieldName "" "\" leading and trailing spaces \""
-- Right " leading and trailing spaces "
-pFieldName :: Parser Text
-pFieldName =
-  pQuotedValue <|>
-  T.intercalate "-" . map toS <$> (pIdentifier `sepBy1` dash) <?>
-  "field name (* or [a..z0..9_$])"
-  where
-    isDash :: GenParser Char st ()
-    isDash = try ( char '-' >> notFollowedBy (char '>') )
-    dash :: Parser Char
-    dash = isDash $> '-'
-
-- |
-- Parse json operators in select, order and filters
--
-- >>> P.parse pJsonPath "" "->text"
-- Right [JArrow {jOp = JKey {jVal = "text"}}]
--
-- >>> P.parse pJsonPath "" "->1"
-- Right [JArrow {jOp = JIdx {jVal = "+1"}}]
--
-- >>> P.parse pJsonPath "" "->>text"
-- Right [J2Arrow {jOp = JKey {jVal = "text"}}]
--
-- >>> P.parse pJsonPath "" "->>1"
-- Right [J2Arrow {jOp = JIdx {jVal = "+1"}}]
--
-- >>> P.parse pJsonPath "" "->0,other"
-- Right [JArrow {jOp = JIdx {jVal = "+0"}}]
--
-- >>> P.parse pJsonPath "" "->0.desc"
-- Right [JArrow {jOp = JIdx {jVal = "+0"}}]
--
-- Fails on badly formed negatives
--
-- >>> P.parse pJsonPath "" "->>-78xy"
-- Left (line 1, column 7):
-- unexpected 'x'
-- expecting digit, "->", "::", ".", "," or end of input
--
-- >>> P.parse pJsonPath "" "->>--34"
-- Left (line 1, column 5):
-- unexpected "-"
-- expecting digit
--
-- >>> P.parse pJsonPath "" "->>-xy-4"
-- Left (line 1, column 5):
-- unexpected "x"
-- expecting digit
-pJsonPath :: Parser JsonPath
-pJsonPath = many pJsonOperation
-  where
-    pJsonOperation :: Parser JsonOperation
-    pJsonOperation = pJsonArrow <*> pJsonOperand
-
-    pJsonArrow   =
-      try (string "->>" $> J2Arrow) <|>
-      try (string "->" $> JArrow)
-
-    pJsonOperand =
-      let pJKey = JKey . toS <$> pFieldName
-          pJIdx = JIdx . toS <$> ((:) <$> P.option '+' (char '-') <*> many1 digit) <* pEnd
-          pEnd = try (void $ lookAhead (string "->")) <|>
-                 try (void $ lookAhead (string "::")) <|>
-                 try (void $ lookAhead (string ".")) <|>
-                 try (void $ lookAhead (string ",")) <|>
-                 try eof in
-      try pJIdx <|> try pJKey
-
-pField :: Parser Field
-pField = lexeme $ (,) <$> pFieldName <*> P.option [] pJsonPath
-
-aliasSeparator :: Parser ()
-aliasSeparator = char ':' >> notFollowedBy (char ':')
-
-- |
-- Parse regular fields in select
--
-- >>> P.parse pRelationSelect "" "rel(*)"
-- Right (SelectRelation {selRelation = "rel", selAlias = Nothing, selHint = Nothing, selJoinType = Nothing})
--
-- >>> P.parse pRelationSelect "" "alias:rel(*)"
-- Right (SelectRelation {selRelation = "rel", selAlias = Just "alias", selHint = Nothing, selJoinType = Nothing})
--
-- >>> P.parse pRelationSelect "" "rel!hint(*)"
-- Right (SelectRelation {selRelation = "rel", selAlias = Nothing, selHint = Just "hint", selJoinType = Nothing})
--
-- >>> P.parse pRelationSelect "" "rel!inner(*)"
-- Right (SelectRelation {selRelation = "rel", selAlias = Nothing, selHint = Nothing, selJoinType = Just JTInner})
--
-- >>> P.parse pRelationSelect "" "rel!hint!inner(*)"
-- Right (SelectRelation {selRelation = "rel", selAlias = Nothing, selHint = Just "hint", selJoinType = Just JTInner})
--
-- >>> P.parse pRelationSelect "" "alias:rel!inner!hint(*)"
-- Right (SelectRelation {selRelation = "rel", selAlias = Just "alias", selHint = Just "hint", selJoinType = Just JTInner})
--
-- >>> P.parse pRelationSelect "" "rel->jsonpath(*)"
-- Left (line 1, column 6):
-- unexpected '>'
--
-- >>> P.parse pRelationSelect "" "rel->jsonpath!hint(*)"
-- Left (line 1, column 6):
-- unexpected '>'
-pRelationSelect :: Parser SelectItem
-pRelationSelect = lexeme $ do
-    alias <- optionMaybe ( try(pFieldName <* aliasSeparator) )
-    name <- pFieldName
-    (hint, jType) <- pEmbedParams
-    try (void $ lookAhead (string "("))
-    return $ SelectRelation name alias hint jType
-
-- |
-- Parse regular fields in select
--
-- >>> P.parse pFieldSelect "" "name"
-- Right (SelectField {selField = ("name",[]), selCast = Nothing, selAlias = Nothing})
--
-- >>> P.parse pFieldSelect "" "name->jsonpath"
-- Right (SelectField {selField = ("name",[JArrow {jOp = JKey {jVal = "jsonpath"}}]), selCast = Nothing, selAlias = Nothing})
--
-- >>> P.parse pFieldSelect "" "name::cast"
-- Right (SelectField {selField = ("name",[]), selCast = Just "cast", selAlias = Nothing})
--
-- >>> P.parse pFieldSelect "" "alias:name"
-- Right (SelectField {selField = ("name",[]), selCast = Nothing, selAlias = Just "alias"})
--
-- >>> P.parse pFieldSelect "" "alias:name->jsonpath::cast"
-- Right (SelectField {selField = ("name",[JArrow {jOp = JKey {jVal = "jsonpath"}}]), selCast = Just "cast", selAlias = Just "alias"})
--
-- >>> P.parse pFieldSelect "" "*"
-- Right (SelectField {selField = ("*",[]), selCast = Nothing, selAlias = Nothing})
--
-- >>> P.parse pFieldSelect "" "name!hint"
-- Left (line 1, column 5):
-- unexpected '!'
-- expecting letter, digit, "-", "->>", "->", "::", ")", "," or end of input
--
-- >>> P.parse pFieldSelect "" "*!hint"
-- Left (line 1, column 2):
-- unexpected '!'
-- expecting ")", "," or end of input
--
-- >>> P.parse pFieldSelect "" "name::"
-- Left (line 1, column 7):
-- unexpected end of input
-- expecting letter or digit
-pFieldSelect :: Parser SelectItem
-pFieldSelect = lexeme $ try (do
-    s <- pStar
-    pEnd
-    return $ SelectField (s, []) Nothing Nothing)
-  <|> do
-    alias <- optionMaybe ( try(pFieldName <* aliasSeparator) )
-    fld <- pField
-    cast' <- optionMaybe (string "::" *> pIdentifier)
-    pEnd
-    return $ SelectField fld (toS <$> cast') alias
-  where
-    pEnd = try (void $ lookAhead (string ")")) <|>
-           try (void $ lookAhead (string ",")) <|>
-           try eof
-    pStar = string "*" $> "*"
-
-
-- |
-- Parse spread relations in select
--
-- >>> P.parse pSpreadRelationSelect "" "...rel(*)"
-- Right (SpreadRelation {selRelation = "rel", selHint = Nothing, selJoinType = Nothing})
--
-- >>> P.parse pSpreadRelationSelect "" "...rel!hint!inner(*)"
-- Right (SpreadRelation {selRelation = "rel", selHint = Just "hint", selJoinType = Just JTInner})
--
-- >>> P.parse pSpreadRelationSelect "" "rel(*)"
-- Left (line 1, column 1):
-- unexpected "r"
-- expecting "..."
--
-- >>> P.parse pSpreadRelationSelect "" "alias:...rel(*)"
-- Left (line 1, column 1):
-- unexpected "a"
-- expecting "..."
--
-- >>> P.parse pSpreadRelationSelect "" "...rel->jsonpath(*)"
-- Left (line 1, column 9):
-- unexpected '>'
-pSpreadRelationSelect :: Parser SelectItem
-pSpreadRelationSelect = lexeme $ do
-    name <- string "..." >> pFieldName
-    (hint, jType) <- pEmbedParams
-    try (void $ lookAhead (string "("))
-    return $ SpreadRelation name hint jType
-
-pEmbedParams :: Parser (Maybe Hint, Maybe JoinType)
-pEmbedParams = do
-  prm1 <- optionMaybe pEmbedParam
-  prm2 <- optionMaybe pEmbedParam
-  return (embedParamHint prm1 <|> embedParamHint prm2, embedParamJoin prm1 <|> embedParamJoin prm2)
-  where
-    pEmbedParam :: Parser EmbedParam
-    pEmbedParam =
-      char '!' *> (
-        try (string "left"  $> EPJoinType JTLeft)  <|>
-        try (string "inner" $> EPJoinType JTInner) <|>
-        try (EPHint <$> pFieldName))
-    embedParamHint prm = case prm of
-      Just (EPHint hint) -> Just hint
-      _                  -> Nothing
-    embedParamJoin prm = case prm of
-      Just (EPJoinType jt) -> Just jt
-      _                    -> Nothing
-
-- |
-- Parse operator expression used in horizontal filtering
--
-- >>> P.parse (pOpExpr pSingleVal) "" "fts().value"
-- Left (line 1, column 5):
-- unexpected ")"
-- expecting operator (eq, gt, ...)
--
-- >>> P.parse (pOpExpr pSingleVal) "" "eq(any).value"
-- Right (OpExpr False (OpQuant OpEqual (Just QuantAny) "value"))
--
-- >>> P.parse (pOpExpr pSingleVal) "" "eq(all).value"
-- Right (OpExpr False (OpQuant OpEqual (Just QuantAll) "value"))
--
-- >>> P.parse (pOpExpr pSingleVal) "" "not.eq(all).value"
-- Right (OpExpr True (OpQuant OpEqual (Just QuantAll) "value"))
--
-- >>> P.parse (pOpExpr pSingleVal) "" "eq().value"
-- Left (line 1, column 4):
-- unexpected ")"
-- expecting operator (eq, gt, ...)
--
-- >>> P.parse (pOpExpr pSingleVal) "" "is().value"
-- Left (line 1, column 3):
-- unexpected "("
-- expecting operator (eq, gt, ...)
--
-- >>> P.parse (pOpExpr pSingleVal) "" "in().value"
-- Left (line 1, column 3):
-- unexpected "("
-- expecting operator (eq, gt, ...)
-pOpExpr :: Parser SingleVal -> Parser OpExpr
-pOpExpr pSVal = do
-  boolExpr <- try (string "not" *> pDelimiter $> True) <|> pure False
-  OpExpr boolExpr <$> pOperation
-  where
-    pOperation :: Parser Operation
-    pOperation = pIn <|> pIs <|> pIsDist <|> try pFts <|> try pSimpleOp <|> try pQuantOp <?> "operator (eq, gt, ...)"
-
-    pIn = In <$> (try (string "in" *> pDelimiter) *> pListVal)
-    pIs = Is <$> (try (string "is" *> pDelimiter) *> pTriVal)
-
-    pIsDist = IsDistinctFrom <$> (try (string "isdistinct" *> pDelimiter) *> pSVal)
-
-    pSimpleOp = do
-      op <- simpleOperator
-      pDelimiter *> (Op op <$> pSVal)
-
-    pQuantOp = do
-      op <- quantOperator
-      quant <- optionMaybe $ try (between (char '(') (char ')') (try (string "any" $> QuantAny) <|> string "all" $> QuantAll))
-      pDelimiter *> (OpQuant op quant <$> pSVal)
-
-    pTriVal = try (ciString "null"    $> TriNull)
-          <|> try (ciString "unknown" $> TriUnknown)
-          <|> try (ciString "true"    $> TriTrue)
-          <|> try (ciString "false"   $> TriFalse)
-          <?> "null or trilean value (unknown, true, false)"
-
-    pFts = do
-      op <-  try (string "fts"   $> FilterFts)
-         <|> try (string "plfts" $> FilterFtsPlain)
-         <|> try (string "phfts" $> FilterFtsPhrase)
-         <|> try (string "wfts"  $> FilterFtsWebsearch)
-
-      lang <- optionMaybe $ try (between (char '(') (char ')') pIdentifier)
-      pDelimiter >> Fts op (toS <$> lang) <$> pSVal
-
-    -- case insensitive char and string
-    ciChar :: Char -> GenParser Char state Char
-    ciChar c = char c <|> char (toUpper c)
-    ciString :: [Char] -> GenParser Char state [Char]
-    ciString = traverse ciChar
-
-pSingleVal :: Parser SingleVal
-pSingleVal = toS <$> many anyChar
-
-pListVal :: Parser ListVal
-pListVal = lexeme (char '(') *> pListElement `sepBy1` char ',' <* lexeme (char ')')
-
-pListElement :: Parser Text
-pListElement = try (pQuotedValue <* notFollowedBy (noneOf ",)")) <|> (toS <$> many (noneOf ",)"))
-
-pQuotedValue :: Parser Text
-pQuotedValue = toS <$> (char '"' *> many pCharsOrSlashed <* char '"')
-  where
-    pCharsOrSlashed = noneOf "\\\"" <|> (char '\\' *> anyChar)
-
-pDelimiter :: Parser Char
-pDelimiter = char '.' <?> "delimiter (.)"
-
-- |
-- Parses the elements in the order query parameter
--
-- >>> P.parse pOrder "" "name.desc.nullsfirst"
-- Right [OrderTerm {otTerm = ("name",[]), otDirection = Just OrderDesc, otNullOrder = Just OrderNullsFirst}]
--
-- >>> P.parse pOrder "" "json_col->key.asc.nullslast"
-- Right [OrderTerm {otTerm = ("json_col",[JArrow {jOp = JKey {jVal = "key"}}]), otDirection = Just OrderAsc, otNullOrder = Just OrderNullsLast}]
--
-- >>> P.parse pOrder "" "clients(json_col->key).desc.nullsfirst"
-- Right [OrderRelationTerm {otRelation = "clients", otRelTerm = ("json_col",[JArrow {jOp = JKey {jVal = "key"}}]), otDirection = Just OrderDesc, otNullOrder = Just OrderNullsFirst}]
--
-- >>> P.parse pOrder "" "clients(name,id)"
-- Left (line 1, column 8):
-- unexpected '('
-- expecting letter, digit, "-", "->>", "->", delimiter (.), "," or end of input
--
-- >>> P.parse pOrder "" "name,clients(name),id"
-- Right [OrderTerm {otTerm = ("name",[]), otDirection = Nothing, otNullOrder = Nothing},OrderRelationTerm {otRelation = "clients", otRelTerm = ("name",[]), otDirection = Nothing, otNullOrder = Nothing},OrderTerm {otTerm = ("id",[]), otDirection = Nothing, otNullOrder = Nothing}]
--
-- >>> P.parse pOrder "" "id.ac"
-- Left (line 1, column 4):
-- unexpected "c"
-- expecting "asc", "desc", "nullsfirst" or "nullslast"
--
-- >>> P.parse pOrder "" "id.descc"
-- Left (line 1, column 8):
-- unexpected 'c'
-- expecting delimiter (.), "," or end of input
--
-- >>> P.parse pOrder "" "id.nulsfist"
-- Left (line 1, column 4):
-- unexpected "n"
-- expecting "asc", "desc", "nullsfirst" or "nullslast"
--
-- >>> P.parse pOrder "" "id.nullslasttt"
-- Left (line 1, column 13):
-- unexpected 't'
-- expecting "," or end of input
--
-- >>> P.parse pOrder "" "id.smth34"
-- Left (line 1, column 4):
-- unexpected "s"
-- expecting "asc", "desc", "nullsfirst" or "nullslast"
--
-- >>> P.parse pOrder "" "id.asc.nlsfst"
-- Left (line 1, column 8):
-- unexpected "l"
-- expecting "nullsfirst" or "nullslast"
--
-- >>> P.parse pOrder "" "id.asc.nullslasttt"
-- Left (line 1, column 17):
-- unexpected 't'
-- expecting "," or end of input
--
-- >>> P.parse pOrder "" "id.asc.smth34"
-- Left (line 1, column 8):
-- unexpected "s"
-- expecting "nullsfirst" or "nullslast"
-pOrder :: Parser [OrderTerm]
-pOrder = lexeme (try pOrderRelationTerm <|> pOrderTerm) `sepBy1` char ','
-  where
-    pOrderTerm = do
-      fld <- pField
-      dir <- optionMaybe pOrdDir
-      nls <- optionMaybe pNulls <* pEnd <|>
-             pEnd $> Nothing
-      return $ OrderTerm fld dir nls
-
-    pOrderRelationTerm = do
-      nam <- pFieldName
-      fld <- between (char '(') (char ')') pField
-      dir <- optionMaybe pOrdDir
-      nls <- optionMaybe pNulls <* pEnd <|> pEnd $> Nothing
-      return $ OrderRelationTerm nam fld dir nls
-
-    pNulls :: Parser OrderNulls
-    pNulls = try (pDelimiter *> string "nullsfirst" $> OrderNullsFirst) <|>
-             try (pDelimiter *> string "nullslast"  $> OrderNullsLast)
-
-    pOrdDir :: Parser OrderDirection
-    pOrdDir = try (pDelimiter *> string "asc" $> OrderAsc) <|>
-              try (pDelimiter *> string "desc" $> OrderDesc)
-
-    pEnd = try (void $ lookAhead (char ',')) <|> try eof
-
-- |
-- Parses the elements inside or/and
--
-- >>> P.parse pLogicTree "" "or()"
-- Left (line 1, column 4):
-- unexpected ")"
-- expecting field name (* or [a..z0..9_$]), negation operator (not) or logic operator (and, or)
--
-- >>> P.parse pLogicTree "" "or(id.in.1,2,id.eq.3)"
-- Left (line 1, column 10):
-- unexpected "1"
-- expecting "("
--
-- >>> P.parse pLogicTree "" "or)("
-- Left (line 1, column 3):
-- unexpected ")"
-- expecting "("
--
-- >>> P.parse pLogicTree "" "and(ord(id.eq.1,id.eq.1),id.eq.2)"
-- Left (line 1, column 7):
-- unexpected "d"
-- expecting "("
--
-- >>> P.parse pLogicTree "" "or(id.eq.1,not.xor(id.eq.2,id.eq.3))"
-- Left (line 1, column 16):
-- unexpected "x"
-- expecting logic operator (and, or)
-pLogicTree :: Parser LogicTree
-pLogicTree = Stmnt <$> try pLogicFilter
-             <|> Expr <$> pNot <*> pLogicOp <*> (lexeme (char '(') *> pLogicTree `sepBy1` lexeme (char ',') <* lexeme (char ')'))
-  where
-    pLogicFilter :: Parser Filter
-    pLogicFilter = Filter <$> pField <* pDelimiter <*> pOpExpr pLogicSingleVal
-    pNot :: Parser Bool
-    pNot = try (string "not" *> pDelimiter $> True)
-           <|> pure False
-           <?> "negation operator (not)"
-    pLogicOp :: Parser LogicOperator
-    pLogicOp = try (string "and" $> And)
-               <|> string "or" $> Or
-               <?> "logic operator (and, or)"
-
-pLogicSingleVal :: Parser SingleVal
-pLogicSingleVal = try (pQuotedValue <* notFollowedBy (noneOf ",)")) <|> try pPgArray <|> (toS <$> many (noneOf ",)"))
-  where
-    pPgArray :: Parser Text
-    pPgArray =  do
-      a <- string "{"
-      b <- many (noneOf "{}")
-      c <- string "}"
-      pure (toS $ a ++ b ++ c)
-
-pLogicPath :: Parser (EmbedPath, Text)
-pLogicPath = do
-  path <- pFieldName `sepBy1` pDelimiter
-  let op = last path
-      notOp = "not." <> op
-  return (filter (/= "not") (init path), if "not" `elem` path then notOp else op)
-
-pColumns :: Parser [FieldName]
-pColumns = pFieldName `sepBy1` lexeme (char ',')
-
-pIdentifier :: Parser Text
-pIdentifier = T.strip . toS <$> many1 pIdentifierChar
-
-pIdentifierChar :: Parser Char
-pIdentifierChar = letter <|> digit <|> oneOf "_ $"
-
-mapError :: Either ParseError a -> Either QPError a
-mapError = mapLeft translateError
-  where
-    translateError e =
-      QPError message details
-      where
-        message = show $ errorPos e
-        details = T.strip $ T.replace "\n" " " $ toS
-           $ showErrorMessages "or" "unknown parse error" "expecting" "unexpected" "end of input" (errorMessages e)
@@ -1,254 +0,0 @@
-{-# LANGUAGE DuplicateRecordFields #-}
-module PostgREST.ApiRequest.Types
-  ( Alias
-  , Cast
-  , Depth
-  , EmbedParam(..)
-  , ApiRequestError(..)
-  , EmbedPath
-  , Field
-  , Filter(..)
-  , Hint
-  , JoinType(..)
-  , JsonOperand(..)
-  , JsonOperation(..)
-  , JsonPath
-  , ListVal
-  , LogicOperator(..)
-  , LogicTree(..)
-  , NodeName
-  , OpExpr(..)
-  , Operation (..)
-  , OpQuantifier(..)
-  , OrderDirection(..)
-  , OrderNulls(..)
-  , OrderTerm(..)
-  , QPError(..)
-  , RangeError(..)
-  , SingleVal
-  , TrileanVal(..)
-  , SimpleOperator(..)
-  , QuantOperator(..)
-  , FtsOperator(..)
-  , SelectItem(..)
-  ) where
-
-import PostgREST.MediaType                (MediaType (..))
-import PostgREST.SchemaCache.Identifiers  (FieldName,
-                                           QualifiedIdentifier)
-import PostgREST.SchemaCache.Relationship (Relationship,
-                                           RelationshipsMap)
-import PostgREST.SchemaCache.Routine      (Routine (..))
-
-import Protolude
-
-- | The value in `/tbl?select=alias:field::cast`
-data SelectItem
-  = SelectField
-    { selField :: Field
-    , selCast  :: Maybe Cast
-    , selAlias :: Maybe Alias
-    }
-- | The value in `/tbl?select=alias:another_tbl(*)`
-  | SelectRelation
-    { selRelation :: FieldName
-    , selAlias    :: Maybe Alias
-    , selHint     :: Maybe Hint
-    , selJoinType :: Maybe JoinType
-    }
-- | The value in `/tbl?select=...another_tbl(*)`
-  | SpreadRelation
-    { selRelation :: FieldName
-    , selHint     :: Maybe Hint
-    , selJoinType :: Maybe JoinType
-    }
-  deriving (Eq, Show)
-
-data ApiRequestError
-  = AmbiguousRelBetween Text Text [Relationship]
-  | AmbiguousRpc [Routine]
-  | BinaryFieldError MediaType
-  | MediaTypeError [ByteString]
-  | InvalidBody ByteString
-  | InvalidFilters
-  | InvalidRange RangeError
-  | InvalidRpcMethod ByteString
-  | LimitNoOrderError
-  | NotFound
-  | NoRelBetween Text Text (Maybe Text) Text RelationshipsMap
-  | NoRpc Text Text [Text] Bool MediaType Bool [QualifiedIdentifier] [Routine]
-  | NotEmbedded Text
-  | PutLimitNotAllowedError
-  | QueryParamError QPError
-  | RelatedOrderNotToOne Text Text
-  | SpreadNotToOne Text Text
-  | UnacceptableFilter Text
-  | UnacceptableSchema [Text]
-  | UnsupportedMethod ByteString
-  | ColumnNotFound Text Text
-  deriving Show
-
-data QPError = QPError Text Text
-  deriving Show
-data RangeError
-  = NegativeLimit
-  | LowerGTUpper
-  | OutOfBounds Text Text
-  deriving Show
-
-type NodeName = Text
-type Depth = Integer
-
-data OrderTerm
-  = OrderTerm
-    { otTerm      :: Field
-    , otDirection :: Maybe OrderDirection
-    , otNullOrder :: Maybe OrderNulls
-    }
-  | OrderRelationTerm
-    { otRelation  :: FieldName
-    , otRelTerm   :: Field
-    , otDirection :: Maybe OrderDirection
-    , otNullOrder :: Maybe OrderNulls
-    }
-  deriving (Eq, Show)
-
-data OrderDirection
-  = OrderAsc
-  | OrderDesc
-  deriving (Eq, Show)
-
-data OrderNulls
-  = OrderNullsFirst
-  | OrderNullsLast
-  deriving (Eq, Show)
-
-type Field = (FieldName, JsonPath)
-type Cast = Text
-type Alias = Text
-type Hint = Text
-
-data EmbedParam
-  -- | Disambiguates an embedding operation when there's multiple relationships
-  -- between two tables. Can be the name of a foreign key constraint, column
-  -- name or the junction in an m2m relationship.
-  = EPHint Hint
-  | EPJoinType JoinType
-
-data JoinType
-  = JTInner
-  | JTLeft
-  deriving (Eq, Show)
-
-- | Path of the embedded levels, e.g "clients.projects.name=eq.." gives Path
-- ["clients", "projects"]
-type EmbedPath = [Text]
-
-- | Json path operations as specified in
-- https://www.postgresql.org/docs/current/static/functions-json.html
-type JsonPath = [JsonOperation]
-
-- | Represents the single arrow `->` or double arrow `->>` operators
-data JsonOperation
-  = JArrow { jOp :: JsonOperand }
-  | J2Arrow { jOp :: JsonOperand }
-  deriving (Eq, Show, Ord)
-
-- | Represents the key(`->'key'`) or index(`->'1`::int`), the index is Text
-- because we reuse our escaping functons and let pg do the casting with
-- '1'::int
-data JsonOperand
-  = JKey { jVal :: Text }
-  | JIdx { jVal :: Text }
-  deriving (Eq, Show, Ord)
-
-- | Boolean logic expression tree e.g. "and(name.eq.N,or(id.eq.1,id.eq.2))" is:
--
--            And
--           /   \
--  name.eq.N     Or
--               /  \
--         id.eq.1   id.eq.2
-data LogicTree
-  = Expr Bool LogicOperator [LogicTree]
-  | Stmnt Filter
-  deriving (Eq, Show)
-
-data LogicOperator
-  = And
-  | Or
-  deriving (Eq, Show)
-
-data Filter
-  = Filter
-  { field  :: Field
-  , opExpr :: OpExpr
-  }
-  deriving (Eq, Show)
-
-data OpExpr
-  = OpExpr Bool Operation
-  | NoOpExpr Text
-  deriving (Eq, Show)
-
-data OpQuantifier = QuantAny | QuantAll
-  deriving (Eq, Show)
-
-data Operation
-  = Op SimpleOperator SingleVal
-  | OpQuant QuantOperator (Maybe OpQuantifier) SingleVal
-  | In ListVal
-  | Is TrileanVal
-  | IsDistinctFrom SingleVal
-  | Fts FtsOperator (Maybe Language) SingleVal
-  deriving (Eq, Show)
-
-type Language = Text
-
-- | Represents a single value in a filter, e.g. id=eq.singleval
-type SingleVal = Text
-
-- | Represents a list value in a filter, e.g. id=in.(val1,val2,val3)
-type ListVal = [Text]
-
-- | Three-valued logic values
-data TrileanVal
-  = TriTrue
-  | TriFalse
-  | TriNull
-  | TriUnknown
-  deriving (Eq, Show)
-
-- Operators that are quantifiable, i.e. they can be used with the any/all modifiers
-data QuantOperator
-  = OpEqual
-  | OpGreaterThanEqual
-  | OpGreaterThan
-  | OpLessThanEqual
-  | OpLessThan
-  | OpLike
-  | OpILike
-  | OpMatch
-  | OpIMatch
-  deriving (Eq, Show)
-
-data SimpleOperator
-  = OpNotEqual
-  | OpContains
-  | OpContained
-  | OpOverlap
-  | OpStrictlyLeft
-  | OpStrictlyRight
-  | OpNotExtendsRight
-  | OpNotExtendsLeft
-  | OpAdjacent
-  deriving (Eq, Show)
-
--
-- | Operators for full text search operators
-data FtsOperator
-  = FilterFts
-  | FilterFtsPlain
-  | FilterFtsPhrase
-  | FilterFtsWebsearch
-  deriving (Eq, Show)
@@ -17,64 +17,104 @@ module PostgREST.App
  , run
  ) where

-
 import Control.Monad.Except     (liftEither)
 import Data.Either.Combinators  (mapLeft)
-import Data.Maybe               (fromJust)
+import Data.List                (union)
 import Data.String              (IsString (..))
+import Data.Time.Clock          (UTCTime)
 import Network.Wai.Handler.Warp (defaultSettings, setHost, setPort,
                                 setServerName)
 import System.Posix.Types       (FileMode)

-import qualified Data.HashMap.Strict        as HM
-import qualified Data.Text.Encoding         as T
-import qualified Hasql.Transaction.Sessions as SQL
-import qualified Network.Wai                as Wai
-import qualified Network.Wai.Handler.Warp   as Warp
+import qualified Data.ByteString.Char8           as BS
+import qualified Data.ByteString.Lazy            as LBS
+import qualified Data.HashMap.Strict             as M
+import qualified Data.Set                        as S
+import qualified Hasql.DynamicStatements.Snippet as SQL
+import qualified Hasql.Pool                      as SQL
+import qualified Hasql.Transaction               as SQL
+import qualified Hasql.Transaction.Sessions      as SQL
+import qualified Network.HTTP.Types.Header       as HTTP
+import qualified Network.HTTP.Types.Status       as HTTP
+import qualified Network.HTTP.Types.URI          as HTTP
+import qualified Network.Wai                     as Wai
+import qualified Network.Wai.Handler.Warp        as Warp

-import qualified PostgREST.Admin            as Admin
-import qualified PostgREST.ApiRequest       as ApiRequest
-import qualified PostgREST.ApiRequest.Types as ApiRequestTypes
-import qualified PostgREST.AppState         as AppState
-import qualified PostgREST.Auth             as Auth
-import qualified PostgREST.Cors             as Cors
-import qualified PostgREST.Error            as Error
-import qualified PostgREST.Logger           as Logger
-import qualified PostgREST.Plan             as Plan
-import qualified PostgREST.Query            as Query
-import qualified PostgREST.Response         as Response
+import qualified PostgREST.AppState                 as AppState
+import qualified PostgREST.Auth                     as Auth
+import qualified PostgREST.Cors                     as Cors
+import qualified PostgREST.DbStructure              as DbStructure
+import qualified PostgREST.Error                    as Error
+import qualified PostgREST.Logger                   as Logger
+import qualified PostgREST.Middleware               as Middleware
+import qualified PostgREST.OpenAPI                  as OpenAPI
+import qualified PostgREST.Query.QueryBuilder       as QueryBuilder
+import qualified PostgREST.Query.Statements         as Statements
+import qualified PostgREST.RangeQuery               as RangeQuery
+import qualified PostgREST.Request.ApiRequest       as ApiRequest
+import qualified PostgREST.Request.DbRequestBuilder as ReqBuilder

-import PostgREST.ApiRequest          (Action (..), ApiRequest (..),
-                                      Mutation (..), Target (..))
-import PostgREST.AppState            (AppState)
-import PostgREST.Auth                (AuthResult (..))
-import PostgREST.Config              (AppConfig (..))
-import PostgREST.Config.PgVersion    (PgVersion (..))
-import PostgREST.Error               (Error)
-import PostgREST.Query               (DbHandler)
-import PostgREST.SchemaCache         (SchemaCache (..))
-import PostgREST.SchemaCache.Routine (Routine (..))
-import PostgREST.Version             (docsVersion, prettyVersion)
+import PostgREST.AppState                (AppState)
+import PostgREST.Config                  (AppConfig (..),
+                                          LogLevel (..),
+                                          OpenAPIMode (..))
+import PostgREST.Config.PgVersion        (PgVersion (..))
+import PostgREST.ContentType             (ContentType (..))
+import PostgREST.DbStructure             (DbStructure (..),
+                                          tablePKCols)
+import PostgREST.DbStructure.Identifiers (FieldName,
+                                          QualifiedIdentifier (..),
+                                          Schema)
+import PostgREST.DbStructure.Proc        (ProcDescription (..),
+                                          ProcVolatility (..))
+import PostgREST.DbStructure.Table       (Table (..))
+import PostgREST.Error                   (Error)
+import PostgREST.GucHeader               (GucHeader,
+                                          addHeadersIfNotIncluded,
+                                          unwrapGucHeader)
+import PostgREST.Request.ApiRequest      (Action (..),
+                                          ApiRequest (..),
+                                          InvokeMethod (..),
+                                          Target (..))
+import PostgREST.Request.Preferences     (PreferCount (..),
+                                          PreferParameters (..),
+                                          PreferRepresentation (..),
+                                          toAppliedHeader)
+import PostgREST.Request.Types           (ReadRequest, fstFieldNames)
+import PostgREST.Version                 (prettyVersion)
+import PostgREST.Workers                 (connectionWorker, listener)
+
+import qualified PostgREST.ContentType      as ContentType
+import qualified PostgREST.DbStructure.Proc as Proc

 import Protolude hiding (Handler)

+
+data RequestContext = RequestContext
+  { ctxConfig      :: AppConfig
+  , ctxDbStructure :: DbStructure
+  , ctxApiRequest  :: ApiRequest
+  , ctxPgVersion   :: PgVersion
+  }
+
 type Handler = ExceptT Error

+type DbHandler = Handler SQL.Transaction
+
 type SignalHandlerInstaller = AppState -> IO()

 type SocketRunner = Warp.Settings -> Wai.Application -> FileMode -> FilePath -> IO()

+
 run :: SignalHandlerInstaller -> Maybe SocketRunner -> AppState -> IO ()
 run installHandlers maybeRunWithSocket appState = do
  conf@AppConfig{..} <- AppState.getConfig appState
-  AppState.connectionWorker appState -- Loads the initial SchemaCache
+  connectionWorker appState -- Loads the initial DbStructure
  installHandlers appState
  -- reload schema cache + config on NOTIFY
-  AppState.runListener conf appState
+  when configDbChannelEnabled $ listener appState

-  Admin.runAdmin conf appState $ serverSettings conf
-
-  let app = postgrest conf appState (AppState.connectionWorker appState)
+  let app = postgrest configLogLevel appState (connectionWorker appState)

  case configServerUnixSocket of
    Just socket ->
@@ -84,7 +124,7 @@ run installHandlers maybeRunWithSocket appState = do
          AppState.logWithZTime appState $ "Listening on unix socket " <> show socket
          runWithSocket (serverSettings conf) app configServerUnixSocketMode socket
        Nothing ->
-          panic "Cannot run with unix socket on non-unix platforms."
+          panic "Cannot run with socket on non-unix plattforms."
    Nothing ->
      do
        AppState.logWithZTime appState $ "Listening on port " <> show configServerPort
@@ -98,128 +138,477 @@ serverSettings AppConfig{..} =
    & setServerName ("postgrest/" <> prettyVersion)

 -- | PostgREST application
-postgrest :: AppConfig -> AppState.AppState -> IO () -> Wai.Application
-postgrest conf appState connWorker =
-  Response.traceHeaderMiddleware conf .
-  Cors.middleware .
-  Auth.middleware appState .
-  Logger.middleware (configLogLevel conf) $
-    -- fromJust can be used, because the auth middleware will **always** add
-    -- some AuthResult to the vault.
-    \req respond -> case fromJust $ Auth.getResult req of
-      Left err -> respond $ Error.errorResponseFor err
-      Right authResult -> do
-        appConf <- AppState.getConfig appState -- the config must be read again because it can reload
-        maybeSchemaCache <- AppState.getSchemaCache appState
-        pgVer <- AppState.getPgVersion appState
+postgrest :: LogLevel -> AppState.AppState -> IO () -> Wai.Application
+postgrest logLevel appState connWorker =
+  Logger.middleware logLevel .
+  Cors.middleware $
+    \req respond -> do
+      time <- AppState.getTime appState
+      conf <- AppState.getConfig appState
+      maybeDbStructure <- AppState.getDbStructure appState
+      pgVer <- AppState.getPgVersion appState
+      jsonDbS <- AppState.getJsonDbS appState

-        let
-          eitherResponse :: IO (Either Error Wai.Response)
-          eitherResponse =
-            runExceptT $ postgrestResponse appState appConf maybeSchemaCache pgVer authResult req
+      let
+        eitherResponse :: IO (Either Error Wai.Response)
+        eitherResponse =
+          runExceptT $ postgrestResponse conf maybeDbStructure jsonDbS pgVer (AppState.getPool appState) time req

-        response <- either Error.errorResponseFor identity <$> eitherResponse
-        -- Launch the connWorker when the connection is down.  The postgrest
-        -- function can respond successfully (with a stale schema cache) before
-        -- the connWorker is done.
-        when (Response.isServiceUnavailable response) connWorker
-        resp <- do
-          delay <- AppState.getRetryNextIn appState
-          return $ Response.addRetryHint delay response
-        respond resp
+      response <- either Error.errorResponseFor identity <$> eitherResponse
+      -- Launch the connWorker when the connection is down.  The postgrest
+      -- function can respond successfully (with a stale schema cache) before
+      -- the connWorker is done.
+      let isPGAway = Wai.responseStatus response == HTTP.status503
+      when isPGAway connWorker
+      resp <- addRetryHint isPGAway appState response
+      respond resp
+
+addRetryHint :: Bool -> AppState -> Wai.Response -> IO Wai.Response
+addRetryHint shouldAdd appState response = do
+  delay <- AppState.getRetryNextIn appState
+  let h = ("Retry-After", BS.pack $ show delay)
+  return $ Wai.mapResponseHeaders (\hs -> if shouldAdd then h:hs else hs) response

 postgrestResponse
-  :: AppState.AppState
-  -> AppConfig
-  -> Maybe SchemaCache
+  :: AppConfig
+  -> Maybe DbStructure
+  -> ByteString
  -> PgVersion
-  -> AuthResult
+  -> SQL.Pool
+  -> UTCTime
  -> Wai.Request
  -> Handler IO Wai.Response
-postgrestResponse appState conf@AppConfig{..} maybeSchemaCache pgVer authResult@AuthResult{..} req = do
-  sCache <-
-    case maybeSchemaCache of
-      Just sCache ->
-        return sCache
-      Nothing ->
-        throwError Error.NoSchemaCacheError
-
+postgrestResponse conf maybeDbStructure jsonDbS pgVer pool time req = do
  body <- lift $ Wai.strictRequestBody req

-  apiRequest <-
+  dbStructure <-
+    case maybeDbStructure of
+      Just dbStructure ->
+        return dbStructure
+      Nothing ->
+        throwError Error.ConnectionLostError
+
+  apiRequest@ApiRequest{..} <-
    liftEither . mapLeft Error.ApiRequestError $
-      ApiRequest.userApiRequest conf req body
+      ApiRequest.userApiRequest conf dbStructure req body

-  handleRequest authResult conf appState (Just authRole /= configDbAnonRole) configDbPreparedStatements pgVer apiRequest sCache
+  -- The JWT must be checked before touching the db
+  jwtClaims <- Auth.jwtClaims conf (toUtf8Lazy iJWT) time

-runDbHandler :: AppState.AppState -> SQL.IsolationLevel -> SQL.Mode -> Bool -> Bool -> DbHandler b -> Handler IO b
-runDbHandler appState isoLvl mode authenticated prepared handler = do
-  dbResp <- lift $ do
-    let transaction = if prepared then SQL.transaction else SQL.unpreparedTransaction
-    AppState.usePool appState . transaction isoLvl mode $ runExceptT handler
+  let
+    handleReq apiReq =
+      handleRequest $ RequestContext conf dbStructure apiReq pgVer
+
+  runDbHandler pool (txMode apiRequest) jwtClaims (configDbPreparedStatements conf) .
+    Middleware.optionalRollback conf apiRequest $
+      Middleware.runPgLocals conf jwtClaims handleReq apiRequest jsonDbS pgVer
+
+runDbHandler :: SQL.Pool -> SQL.Mode -> Auth.JWTClaims -> Bool -> DbHandler a -> Handler IO a
+runDbHandler pool mode jwtClaims prepared handler = do
+  dbResp <-
+    let transaction = if prepared then SQL.transaction else SQL.unpreparedTransaction in
+    lift . SQL.use pool . transaction SQL.ReadCommitted mode $ runExceptT handler

  resp <-
    liftEither . mapLeft Error.PgErr $
-      mapLeft (Error.PgError authenticated) dbResp
+      mapLeft (Error.PgError $ Auth.containsRole jwtClaims) dbResp

  liftEither resp

-handleRequest :: AuthResult -> AppConfig -> AppState.AppState -> Bool -> Bool -> PgVersion -> ApiRequest -> SchemaCache -> Handler IO Wai.Response
-handleRequest AuthResult{..} conf appState authenticated prepared pgVer apiReq@ApiRequest{..} sCache =
+handleRequest :: RequestContext -> DbHandler Wai.Response
+handleRequest context@(RequestContext _ _ ApiRequest{..} _) =
  case (iAction, iTarget) of
-    (ActionRead headersOnly, TargetIdent identifier) -> do
-      wrPlan <- liftEither $ Plan.wrappedReadPlan identifier conf sCache apiReq
-      resultSet <- runQuery roleIsoLvl (Plan.wrTxMode wrPlan) $ Query.readQuery wrPlan conf apiReq
-      return $ Response.readResponse headersOnly identifier apiReq resultSet
-
-    (ActionMutate MutationCreate, TargetIdent identifier) -> do
-      mrPlan <- liftEither $ Plan.mutateReadPlan MutationCreate apiReq identifier conf sCache
-      resultSet <- runQuery roleIsoLvl (Plan.mrTxMode mrPlan) $ Query.createQuery mrPlan apiReq conf
-      return $ Response.createResponse identifier mrPlan apiReq resultSet
-
-    (ActionMutate MutationUpdate, TargetIdent identifier) -> do
-      mrPlan <- liftEither $ Plan.mutateReadPlan MutationUpdate apiReq identifier conf sCache
-      resultSet <- runQuery roleIsoLvl (Plan.mrTxMode mrPlan) $ Query.updateQuery mrPlan apiReq conf
-      return $ Response.updateResponse apiReq resultSet
-
-    (ActionMutate MutationSingleUpsert, TargetIdent identifier) -> do
-      mrPlan <- liftEither $ Plan.mutateReadPlan MutationSingleUpsert apiReq identifier conf sCache
-      resultSet <- runQuery roleIsoLvl (Plan.mrTxMode mrPlan) $ Query.singleUpsertQuery mrPlan apiReq conf
-      return $ Response.singleUpsertResponse apiReq resultSet
-
-    (ActionMutate MutationDelete, TargetIdent identifier) -> do
-      mrPlan <- liftEither $ Plan.mutateReadPlan MutationDelete apiReq identifier conf sCache
-      resultSet <- runQuery roleIsoLvl (Plan.mrTxMode mrPlan) $ Query.deleteQuery mrPlan apiReq conf
-      return $ Response.deleteResponse apiReq resultSet
-
-    (ActionInvoke invMethod, TargetProc identifier _) -> do
-      cPlan <- liftEither $ Plan.callReadPlan identifier conf sCache apiReq invMethod
-      resultSet <- runQuery (fromMaybe roleIsoLvl $ pdIsoLvl (Plan.crProc cPlan))(Plan.crTxMode cPlan) $ Query.invokeQuery (Plan.crProc cPlan) cPlan apiReq conf pgVer
-      return $ Response.invokeResponse invMethod (Plan.crProc cPlan) apiReq resultSet
-
-    (ActionInspect headersOnly, TargetDefaultSpec tSchema) -> do
-      oaiResult <- runQuery roleIsoLvl Plan.inspectPlanTxMode $ Query.openApiQuery sCache pgVer conf tSchema
-      return $ Response.openApiResponse (T.decodeUtf8 prettyVersion, docsVersion) headersOnly oaiResult conf sCache iSchema iNegotiatedByProfile
-
+    (ActionRead headersOnly, TargetIdent identifier) ->
+      handleRead headersOnly identifier context
+    (ActionCreate, TargetIdent identifier) ->
+      handleCreate identifier context
+    (ActionUpdate, TargetIdent identifier) ->
+      handleUpdate identifier context
+    (ActionSingleUpsert, TargetIdent identifier) ->
+      handleSingleUpsert identifier context
+    (ActionDelete, TargetIdent identifier) ->
+      handleDelete identifier context
    (ActionInfo, TargetIdent identifier) ->
-      return $ Response.infoIdentResponse identifier sCache
-
-    (ActionInfo, TargetProc identifier _) -> do
-      cPlan <- liftEither $ Plan.callReadPlan identifier conf sCache apiReq ApiRequest.InvHead
-      return $ Response.infoProcResponse (Plan.crProc cPlan)
-
-    (ActionInfo, TargetDefaultSpec _) ->
-      return Response.infoRootResponse
-
+      handleInfo identifier context
+    (ActionInvoke invMethod, TargetProc proc _) ->
+      handleInvoke invMethod proc context
+    (ActionInspect headersOnly, TargetDefaultSpec tSchema) ->
+      handleOpenApi headersOnly tSchema context
    _ ->
-      -- This is unreachable as the ApiRequest.hs rejects it before
-      -- TODO Refactor the Action/Target types to remove this line
-      throwError $ Error.ApiRequestError ApiRequestTypes.NotFound
+      throwError Error.NotFound
+
+handleRead :: Bool -> QualifiedIdentifier -> RequestContext -> DbHandler Wai.Response
+handleRead headersOnly identifier context@RequestContext{..} = do
+  req <- readRequest identifier context
+  bField <- binaryField context req
+
+  let
+    ApiRequest{..} = ctxApiRequest
+    AppConfig{..} = ctxConfig
+    countQuery = QueryBuilder.readRequestToCountQuery req
+
+  (tableTotal, queryTotal, _ , body, gucHeaders, gucStatus) <-
+    lift . SQL.statement mempty $
+      Statements.createReadStatement
+        (QueryBuilder.readRequestToQuery req)
+        (if iPreferCount == Just EstimatedCount then
+           -- LIMIT maxRows + 1 so we can determine below that maxRows was surpassed
+           QueryBuilder.limitedQuery countQuery ((+ 1) <$> configDbMaxRows)
+         else
+           countQuery
+        )
+        (iAcceptContentType == CTSingularJSON)
+        (shouldCount iPreferCount)
+        (iAcceptContentType == CTTextCSV)
+        bField
+        configDbPreparedStatements
+
+  total <- readTotal ctxConfig ctxApiRequest tableTotal countQuery
+  response <- liftEither $ gucResponse <$> gucStatus <*> gucHeaders
+
+  let
+    (status, contentRange) = RangeQuery.rangeStatusHeader iTopLevelRange queryTotal total
+    headers =
+      [ contentRange
+      , ( "Content-Location"
+        , "/"
+            <> toUtf8 (qiName identifier)
+            <> if BS.null iCanonicalQS then mempty else "?" <> iCanonicalQS
+        )
+      ]
+      ++ contentTypeHeaders context
+
+  failNotSingular iAcceptContentType queryTotal . response status headers $
+    if headersOnly then mempty else LBS.fromStrict body
+
+readTotal :: AppConfig -> ApiRequest -> Maybe Int64 -> SQL.Snippet -> DbHandler (Maybe Int64)
+readTotal AppConfig{..} ApiRequest{..} tableTotal countQuery =
+  case iPreferCount of
+    Just PlannedCount ->
+      explain
+    Just EstimatedCount ->
+      if tableTotal > (fromIntegral <$> configDbMaxRows) then
+        max tableTotal <$> explain
+      else
+        return tableTotal
+    _ ->
+      return tableTotal
  where
-    roleSettings = fromMaybe mempty (HM.lookup authRole $ configRoleSettings conf)
-    roleIsoLvl = HM.findWithDefault SQL.ReadCommitted authRole $ configRoleIsoLvl conf
-    runQuery isoLvl mode query =
-      runDbHandler appState isoLvl mode authenticated prepared $ do
-        Query.setPgLocals conf authClaims authRole (HM.toList roleSettings) apiReq pgVer
-        Query.runPreReq conf
-        query
+    explain =
+      lift . SQL.statement mempty . Statements.createExplainStatement countQuery $
+        configDbPreparedStatements
+
+handleCreate :: QualifiedIdentifier -> RequestContext -> DbHandler Wai.Response
+handleCreate identifier@QualifiedIdentifier{..} context@RequestContext{..} = do
+  let
+    ApiRequest{..} = ctxApiRequest
+    pkCols = tablePKCols ctxDbStructure qiSchema qiName
+
+  WriteQueryResult{..} <- writeQuery identifier True pkCols context
+
+  let
+    response = gucResponse resGucStatus resGucHeaders
+    headers =
+      catMaybes
+        [ if null resFields then
+            Nothing
+          else
+            Just
+              ( HTTP.hLocation
+              , "/"
+                  <> toUtf8 qiName
+                  <> HTTP.renderSimpleQuery True (splitKeyValue <$> resFields)
+              )
+        , Just . RangeQuery.contentRangeH 1 0 $
+            if shouldCount iPreferCount then Just resQueryTotal else Nothing
+        , if null pkCols && isNothing iOnConflict then
+            Nothing
+          else
+            toAppliedHeader <$> iPreferResolution
+        ]
+
+  failNotSingular iAcceptContentType resQueryTotal $
+    if iPreferRepresentation == Full then
+      response HTTP.status201 (headers ++ contentTypeHeaders context) (LBS.fromStrict resBody)
+    else
+      response HTTP.status201 headers mempty
+
+handleUpdate :: QualifiedIdentifier -> RequestContext -> DbHandler Wai.Response
+handleUpdate identifier context@(RequestContext _ _ ApiRequest{..} _) = do
+  WriteQueryResult{..} <- writeQuery identifier False mempty context
+
+  let
+    response = gucResponse resGucStatus resGucHeaders
+    fullRepr = iPreferRepresentation == Full
+    updateIsNoOp = S.null iColumns
+    status
+      | resQueryTotal == 0 && not updateIsNoOp = HTTP.status404
+      | fullRepr = HTTP.status200
+      | otherwise = HTTP.status204
+    contentRangeHeader =
+      RangeQuery.contentRangeH 0 (resQueryTotal - 1) $
+        if shouldCount iPreferCount then Just resQueryTotal else Nothing
+
+  failNotSingular iAcceptContentType resQueryTotal $
+    if fullRepr then
+      response status (contentTypeHeaders context ++ [contentRangeHeader]) (LBS.fromStrict resBody)
+    else
+      response status [contentRangeHeader] mempty
+
+handleSingleUpsert :: QualifiedIdentifier -> RequestContext-> DbHandler Wai.Response
+handleSingleUpsert identifier context@(RequestContext _ _ ApiRequest{..} _) = do
+  when (iTopLevelRange /= RangeQuery.allRange) $
+    throwError Error.PutRangeNotAllowedError
+
+  WriteQueryResult{..} <- writeQuery identifier False mempty context
+
+  let response = gucResponse resGucStatus resGucHeaders
+
+  -- Makes sure the querystring pk matches the payload pk
+  -- e.g. PUT /items?id=eq.1 { "id" : 1, .. } is accepted,
+  -- PUT /items?id=eq.14 { "id" : 2, .. } is rejected.
+  -- If this condition is not satisfied then nothing is inserted,
+  -- check the WHERE for INSERT in QueryBuilder.hs to see how it's done
+  when (resQueryTotal /= 1) $ do
+    lift SQL.condemn
+    throwError Error.PutMatchingPkError
+
+  return $
+    if iPreferRepresentation == Full then
+      response HTTP.status200 (contentTypeHeaders context) (LBS.fromStrict resBody)
+    else
+      response HTTP.status204 (contentTypeHeaders context) mempty
+
+handleDelete :: QualifiedIdentifier -> RequestContext -> DbHandler Wai.Response
+handleDelete identifier context@(RequestContext _ _ ApiRequest{..} _) = do
+  WriteQueryResult{..} <- writeQuery identifier False mempty context
+
+  let
+    response = gucResponse resGucStatus resGucHeaders
+    contentRangeHeader =
+      RangeQuery.contentRangeH 1 0 $
+        if shouldCount iPreferCount then Just resQueryTotal else Nothing
+
+  failNotSingular iAcceptContentType resQueryTotal $
+    if iPreferRepresentation == Full then
+      response HTTP.status200
+        (contentTypeHeaders context ++ [contentRangeHeader])
+        (LBS.fromStrict resBody)
+    else
+      response HTTP.status204 [contentRangeHeader] mempty
+
+handleInfo :: Monad m => QualifiedIdentifier -> RequestContext -> Handler m Wai.Response
+handleInfo identifier RequestContext{..} =
+  case find tableMatches $ dbTables ctxDbStructure of
+    Just table ->
+      return $ Wai.responseLBS HTTP.status200 [allOrigins, allowH table] mempty
+    Nothing ->
+      throwError Error.NotFound
+  where
+    allOrigins = ("Access-Control-Allow-Origin", "*")
+    allowH table =
+      ( HTTP.hAllow
+      , BS.intercalate "," $
+          ["OPTIONS,GET,HEAD"]
+          ++ ["POST" | tableInsertable table]
+          ++ ["PUT" | tableInsertable table && tableUpdatable table && hasPK]
+          ++ ["PATCH" | tableUpdatable table]
+          ++ ["DELETE" | tableDeletable table]
+      )
+    tableMatches table =
+      tableName table == qiName identifier
+      && tableSchema table == qiSchema identifier
+    hasPK =
+      not $ null $ tablePKCols ctxDbStructure (qiSchema identifier) (qiName identifier)
+
+handleInvoke :: InvokeMethod -> ProcDescription -> RequestContext -> DbHandler Wai.Response
+handleInvoke invMethod proc context@RequestContext{..} = do
+  let
+    ApiRequest{..} = ctxApiRequest
+
+    identifier =
+      QualifiedIdentifier
+        (pdSchema proc)
+        (fromMaybe (pdName proc) $ Proc.procTableName proc)
+
+  req <- readRequest identifier context
+  bField <- binaryField context req
+
+  let callReq = ReqBuilder.callRequest proc ctxApiRequest req
+
+  (tableTotal, queryTotal, body, gucHeaders, gucStatus) <-
+    lift . SQL.statement mempty $
+      Statements.callProcStatement
+        (Proc.procReturnsScalar proc)
+        (Proc.procReturnsSingle proc)
+        (QueryBuilder.requestToCallProcQuery callReq)
+        (QueryBuilder.readRequestToQuery req)
+        (QueryBuilder.readRequestToCountQuery req)
+        (shouldCount iPreferCount)
+        (iAcceptContentType == CTSingularJSON)
+        (iAcceptContentType == CTTextCSV)
+        (iPreferParameters == Just MultipleObjects)
+        bField
+        (configDbPreparedStatements ctxConfig)
+
+  response <- liftEither $ gucResponse <$> gucStatus <*> gucHeaders
+
+  let
+    (status, contentRange) =
+      RangeQuery.rangeStatusHeader iTopLevelRange queryTotal tableTotal
+
+  failNotSingular iAcceptContentType queryTotal $
+    response status
+      (contentTypeHeaders context ++ [contentRange])
+      (if invMethod == InvHead then mempty else LBS.fromStrict body)
+
+handleOpenApi :: Bool -> Schema -> RequestContext -> DbHandler Wai.Response
+handleOpenApi headersOnly tSchema (RequestContext conf@AppConfig{..} dbStructure apiRequest ctxPgVersion) = do
+  body <-
+    lift $ case configOpenApiMode of
+      OAFollowPriv ->
+        OpenAPI.encode conf dbStructure
+           <$> SQL.statement tSchema (DbStructure.accessibleTables ctxPgVersion configDbPreparedStatements)
+           <*> SQL.statement tSchema (DbStructure.accessibleProcs ctxPgVersion configDbPreparedStatements)
+           <*> SQL.statement tSchema (DbStructure.schemaDescription configDbPreparedStatements)
+      OAIgnorePriv ->
+        OpenAPI.encode conf dbStructure
+              (filter (\x -> tableSchema x == tSchema) $ DbStructure.dbTables dbStructure)
+              (M.filterWithKey (\(QualifiedIdentifier sch _) _ ->  sch == tSchema) $ DbStructure.dbProcs dbStructure)
+          <$> SQL.statement tSchema (DbStructure.schemaDescription configDbPreparedStatements)
+      OADisabled ->
+        pure mempty
+
+  return $
+    Wai.responseLBS HTTP.status200
+      (ContentType.toHeader CTOpenAPI : maybeToList (profileHeader apiRequest))
+      (if headersOnly then mempty else body)
+
+txMode :: ApiRequest -> SQL.Mode
+txMode ApiRequest{..} =
+  case (iAction, iTarget) of
+    (ActionRead _, _) ->
+      SQL.Read
+    (ActionInfo, _) ->
+      SQL.Read
+    (ActionInspect _, _) ->
+      SQL.Read
+    (ActionInvoke InvGet, _) ->
+      SQL.Read
+    (ActionInvoke InvHead, _) ->
+      SQL.Read
+    (ActionInvoke InvPost, TargetProc ProcDescription{pdVolatility=Stable} _) ->
+      SQL.Read
+    (ActionInvoke InvPost, TargetProc ProcDescription{pdVolatility=Immutable} _) ->
+      SQL.Read
+    _ ->
+      SQL.Write
+
+-- | Result from executing a write query on the database
+data WriteQueryResult = WriteQueryResult
+  { resQueryTotal :: Int64
+  , resFields     :: [ByteString]
+  , resBody       :: ByteString
+  , resGucStatus  :: Maybe HTTP.Status
+  , resGucHeaders :: [GucHeader]
+  }
+
+writeQuery :: QualifiedIdentifier -> Bool -> [Text] -> RequestContext -> DbHandler WriteQueryResult
+writeQuery identifier@QualifiedIdentifier{..} isInsert pkCols context@RequestContext{..} = do
+  readReq <- readRequest identifier context
+
+  mutateReq <-
+    liftEither $
+      ReqBuilder.mutateRequest qiSchema qiName ctxApiRequest
+        (tablePKCols ctxDbStructure qiSchema qiName)
+        readReq
+
+  (_, queryTotal, fields, body, gucHeaders, gucStatus) <-
+    lift . SQL.statement mempty $
+      Statements.createWriteStatement
+        (QueryBuilder.readRequestToQuery readReq)
+        (QueryBuilder.mutateRequestToQuery mutateReq)
+        (iAcceptContentType ctxApiRequest == CTSingularJSON)
+        isInsert
+        (iAcceptContentType ctxApiRequest == CTTextCSV)
+        (iPreferRepresentation ctxApiRequest)
+        pkCols
+        (configDbPreparedStatements ctxConfig)
+
+  liftEither $ WriteQueryResult queryTotal fields body <$> gucStatus <*> gucHeaders
+
+-- | Response with headers and status overridden from GUCs.
+gucResponse
+  :: Maybe HTTP.Status
+  -> [GucHeader]
+  -> HTTP.Status
+  -> [HTTP.Header]
+  -> LBS.ByteString
+  -> Wai.Response
+gucResponse gucStatus gucHeaders status headers =
+  Wai.responseLBS (fromMaybe status gucStatus) $
+    addHeadersIfNotIncluded headers (map unwrapGucHeader gucHeaders)
+
+-- |
+-- Fail a response if a single JSON object was requested and not exactly one
+-- was found.
+failNotSingular :: ContentType -> Int64 -> Wai.Response -> DbHandler Wai.Response
+failNotSingular contentType queryTotal response =
+  if contentType == CTSingularJSON && queryTotal /= 1 then
+    do
+      lift SQL.condemn
+      throwError $ Error.singularityError queryTotal
+  else
+    return response
+
+shouldCount :: Maybe PreferCount -> Bool
+shouldCount preferCount =
+  preferCount == Just ExactCount || preferCount == Just EstimatedCount
+
+returnsScalar :: ApiRequest.Target -> Bool
+returnsScalar (TargetProc proc _) = Proc.procReturnsScalar proc
+returnsScalar _                   = False
+
+readRequest :: Monad m => QualifiedIdentifier -> RequestContext -> Handler m ReadRequest
+readRequest QualifiedIdentifier{..} (RequestContext AppConfig{..} dbStructure apiRequest _) =
+  liftEither $
+    ReqBuilder.readRequest qiSchema qiName configDbMaxRows
+      (dbRelationships dbStructure)
+      apiRequest
+
+contentTypeHeaders :: RequestContext -> [HTTP.Header]
+contentTypeHeaders RequestContext{..} =
+  ContentType.toHeader (iAcceptContentType ctxApiRequest) : maybeToList (profileHeader ctxApiRequest)
+
+-- | If raw(binary) output is requested, check that ContentType is one of the
+-- admitted rawContentTypes and that`?select=...` contains only one field other
+-- than `*`
+binaryField :: Monad m => RequestContext -> ReadRequest -> Handler m (Maybe FieldName)
+binaryField RequestContext{..} readReq
+  | returnsScalar (iTarget ctxApiRequest) && iAcceptContentType ctxApiRequest `elem` rawContentTypes ctxConfig =
+      return $ Just "pgrst_scalar"
+  | iAcceptContentType ctxApiRequest `elem` rawContentTypes ctxConfig =
+      let
+        fldNames = fstFieldNames readReq
+        fieldName = headMay fldNames
+      in
+      if length fldNames == 1 && fieldName /= Just "*" then
+        return fieldName
+      else
+        throwError $ Error.BinaryFieldError (iAcceptContentType ctxApiRequest)
+  | otherwise =
+      return Nothing
+
+rawContentTypes :: AppConfig -> [ContentType]
+rawContentTypes AppConfig{..} =
+  (ContentType.decodeContentType <$> configRawMediaTypes) `union` [CTOctetStream, CTTextPlain]
+
+profileHeader :: ApiRequest -> Maybe HTTP.Header
+profileHeader ApiRequest{..} =
+  (,) "Content-Profile" <$> (toUtf8 <$> iProfile)
+
+splitKeyValue :: ByteString -> (ByteString, ByteString)
+splitKeyValue kv =
+  (k, BS.tail v)
+  where
+    (k, v) = BS.break (== '=') kv
@@ -1,162 +1,98 @@
-{-# LANGUAGE LambdaCase      #-}
-{-# LANGUAGE NamedFieldPuns  #-}
 {-# LANGUAGE RecordWildCards #-}

 module PostgREST.AppState
  ( AppState
-  , destroy
  , getConfig
-  , getSchemaCache
-  , getIsListenerOn
+  , getDbStructure
+  , getIsWorkerOn
+  , getJsonDbS
  , getMainThreadId
  , getPgVersion
-  , getRetryNextIn
+  , getPool
  , getTime
+  , getRetryNextIn
  , init
  , initWithPool
  , logWithZTime
-  , putSchemaCache
+  , putConfig
+  , putDbStructure
+  , putIsWorkerOn
+  , putJsonDbS
  , putPgVersion
-  , usePool
-  , loadSchemaCache
-  , reReadConfig
-  , connectionWorker
-  , runListener
+  , putRetryNextIn
+  , releasePool
+  , signalListener
+  , waitListener
  ) where

-import qualified Data.ByteString.Char8      as BS
-import qualified Data.ByteString.Lazy       as LBS
-import           Data.Either.Combinators    (whenLeft)
-import qualified Data.Text.Encoding         as T
-import           Hasql.Connection           (acquire)
-import qualified Hasql.Notifications        as SQL
-import qualified Hasql.Pool                 as SQL
-import qualified Hasql.Session              as SQL
-import qualified Hasql.Transaction.Sessions as SQL
-import qualified PostgREST.Error            as Error
-import           PostgREST.Version          (prettyVersion)
+import qualified Hasql.Pool as SQL

 import Control.AutoUpdate (defaultUpdateSettings, mkAutoUpdate,
                           updateAction)
-import Control.Debounce
-import Control.Retry      (RetryStatus, capDelay, exponentialBackoff,
-                           retrying, rsPreviousDelay)
 import Data.IORef         (IORef, atomicWriteIORef, newIORef,
                           readIORef)
 import Data.Time          (ZonedTime, defaultTimeLocale, formatTime,
                           getZonedTime)
 import Data.Time.Clock    (UTCTime, getCurrentTime)

-import PostgREST.Config                  (AppConfig (..),
-                                          addFallbackAppName,
-                                          readAppConfig)
-import PostgREST.Config.Database         (queryDbSettings,
-                                          queryPgVersion,
-                                          queryRoleSettings)
-import PostgREST.Config.PgVersion        (PgVersion (..),
-                                          minimumPgVersion)
-import PostgREST.SchemaCache             (SchemaCache,
-                                          querySchemaCache)
-import PostgREST.SchemaCache.Identifiers (dumpQi)
+import PostgREST.Config           (AppConfig (..))
+import PostgREST.Config.PgVersion (PgVersion (..), minimumPgVersion)
+import PostgREST.DbStructure      (DbStructure)

 import Protolude


 data AppState = AppState
-  -- | Database connection pool
-  { statePool                     :: SQL.Pool
-  -- | Database server version, will be updated by the connectionWorker
-  , statePgVersion                :: IORef PgVersion
+  { statePool         :: SQL.Pool -- | Connection pool, either a 'Connection' or a 'ConnectionError'
+  , statePgVersion    :: IORef PgVersion
  -- | No schema cache at the start. Will be filled in by the connectionWorker
-  , stateSchemaCache              :: IORef (Maybe SchemaCache)
-  -- | starts the connection worker with a debounce
-  , debouncedConnectionWorker     :: IO ()
+  , stateDbStructure  :: IORef (Maybe DbStructure)
+  -- | Cached DbStructure in json
+  , stateJsonDbS      :: IORef ByteString
+  -- | Helper ref to make sure just one connectionWorker can run at a time
+  , stateIsWorkerOn   :: IORef Bool
  -- | Binary semaphore used to sync the listener(NOTIFY reload) with the connectionWorker.
-  , stateListener                 :: MVar ()
-  -- | State of the LISTEN channel, used for the admin server checks
-  , stateIsListenerOn             :: IORef Bool
+  , stateListener     :: MVar ()
  -- | Config that can change at runtime
-  , stateConf                     :: IORef AppConfig
+  , stateConf         :: IORef AppConfig
  -- | Time used for verifying JWT expiration
-  , stateGetTime                  :: IO UTCTime
+  , stateGetTime      :: IO UTCTime
  -- | Time with time zone used for worker logs
-  , stateGetZTime                 :: IO ZonedTime
+  , stateGetZTime     :: IO ZonedTime
  -- | Used for killing the main thread in case a subthread fails
-  , stateMainThreadId             :: ThreadId
+  , stateMainThreadId :: ThreadId
  -- | Keeps track of when the next retry for connecting to database is scheduled
-  , stateRetryNextIn              :: IORef Int
-  -- | Logs a pool error with a debounce
-  , debounceLogAcquisitionTimeout :: IO ()
+  , stateRetryNextIn  :: IORef Int
  }

 init :: AppConfig -> IO AppState
 init conf = do
-  pool <- initPool conf
-  initWithPool pool conf
+  newPool <- initPool conf
+  initWithPool newPool conf

 initWithPool :: SQL.Pool -> AppConfig -> IO AppState
-initWithPool pool conf = do
-  appState <- AppState pool
+initWithPool newPool conf =
+  AppState newPool
    <$> newIORef minimumPgVersion -- assume we're in a supported version when starting, this will be corrected on a later step
    <*> newIORef Nothing
-    <*> pure (pure ())
-    <*> newEmptyMVar
+    <*> newIORef mempty
    <*> newIORef False
+    <*> newEmptyMVar
    <*> newIORef conf
    <*> mkAutoUpdate defaultUpdateSettings { updateAction = getCurrentTime }
    <*> mkAutoUpdate defaultUpdateSettings { updateAction = getZonedTime }
    <*> myThreadId
    <*> newIORef 0
-    <*> pure (pure ())
-
-
-  debLogTimeout <-
-    let oneSecond = 1000000 in
-    mkDebounce defaultDebounceSettings
-       { debounceAction = logPgrstError appState SQL.AcquisitionTimeoutUsageError
-       , debounceFreq = 5*oneSecond
-       , debounceEdge = leadingEdge -- logs at the start and the end
-       }
-
-  debWorker <-
-    let decisecond = 100000 in
-    mkDebounce defaultDebounceSettings
-       { debounceAction = internalConnectionWorker appState
-       , debounceFreq = decisecond
-       , debounceEdge = leadingEdge -- runs the worker at the start and the end
-       }
-
-  return appState { debounceLogAcquisitionTimeout = debLogTimeout, debouncedConnectionWorker = debWorker }
-
-destroy :: AppState -> IO ()
-destroy = destroyPool

 initPool :: AppConfig -> IO SQL.Pool
 initPool AppConfig{..} =
-  SQL.acquire
-    configDbPoolSize
-    (fromIntegral configDbPoolAcquisitionTimeout)
-    (fromIntegral configDbPoolMaxLifetime)
-    (fromIntegral configDbPoolMaxIdletime)
-    (toUtf8 $ addFallbackAppName prettyVersion configDbUri)
+  SQL.acquire (configDbPoolSize, configDbPoolTimeout, toUtf8 configDbUri)

-- | Run an action with a database connection.
-usePool :: AppState -> SQL.Session a -> IO (Either SQL.UsageError a)
-usePool AppState{..} x = do
-  res <- SQL.use statePool x
-  whenLeft res (\case
-    SQL.AcquisitionTimeoutUsageError -> debounceLogAcquisitionTimeout -- this can happen rapidly for many requests, so we debounce
-    _                                -> pure ())
-  return res
+getPool :: AppState -> SQL.Pool
+getPool = statePool

-- | Flush the connection pool so that any future use of the pool will
-- use connections freshly established after this call.
-flushPool :: AppState -> IO ()
-flushPool AppState{..} = SQL.release statePool
-
-- | Destroy the pool on shutdown.
-destroyPool :: AppState -> IO ()
-destroyPool AppState{..} = SQL.release statePool
+releasePool :: AppState -> IO ()
+releasePool AppState{..} = SQL.release statePool >> throwTo stateMainThreadId UserInterrupt

 getPgVersion :: AppState -> IO PgVersion
 getPgVersion = readIORef . statePgVersion
@@ -164,14 +100,24 @@ getPgVersion = readIORef . statePgVersion
 putPgVersion :: AppState -> PgVersion -> IO ()
 putPgVersion = atomicWriteIORef . statePgVersion

-getSchemaCache :: AppState -> IO (Maybe SchemaCache)
-getSchemaCache = readIORef . stateSchemaCache
+getDbStructure :: AppState -> IO (Maybe DbStructure)
+getDbStructure = readIORef . stateDbStructure

-putSchemaCache :: AppState -> Maybe SchemaCache -> IO ()
-putSchemaCache appState = atomicWriteIORef (stateSchemaCache appState)
+putDbStructure :: AppState -> DbStructure -> IO ()
+putDbStructure appState structure =
+  atomicWriteIORef (stateDbStructure appState) $ Just structure

-connectionWorker :: AppState -> IO ()
-connectionWorker = debouncedConnectionWorker
+getJsonDbS :: AppState -> IO ByteString
+getJsonDbS = readIORef . stateJsonDbS
+
+putJsonDbS :: AppState -> ByteString -> IO ()
+putJsonDbS appState = atomicWriteIORef (stateJsonDbS appState)
+
+getIsWorkerOn :: AppState -> IO Bool
+getIsWorkerOn = readIORef . stateIsWorkerOn
+
+putIsWorkerOn :: AppState -> Bool -> IO ()
+putIsWorkerOn = atomicWriteIORef . stateIsWorkerOn

 getRetryNextIn :: AppState -> IO Int
 getRetryNextIn = readIORef . stateRetryNextIn
@@ -194,9 +140,6 @@ logWithZTime appState txt = do
  zTime <- stateGetZTime appState
  hPutStrLn stderr $ toS (formatTime defaultTimeLocale "%d/%b/%Y:%T %z: " zTime) <> txt

-logPgrstError :: AppState -> SQL.UsageError -> IO ()
-logPgrstError appState e = logWithZTime appState . T.decodeUtf8 . LBS.toStrict $ Error.errorPayload $ Error.PgError False e
-
 getMainThreadId :: AppState -> ThreadId
 getMainThreadId = stateMainThreadId

@@ -210,269 +153,3 @@ waitListener = takeMVar . stateListener
 -- the connectionWorker is the only mvar producer.
 signalListener :: AppState -> IO ()
 signalListener appState = void $ tryPutMVar (stateListener appState) ()
-
-getIsListenerOn :: AppState -> IO Bool
-getIsListenerOn = readIORef . stateIsListenerOn
-
-putIsListenerOn :: AppState -> Bool -> IO ()
-putIsListenerOn = atomicWriteIORef . stateIsListenerOn
-
-- | Schema cache status
-data SCacheStatus
-  = SCLoaded
-  | SCOnRetry
-  | SCFatalFail
-
-- | Load the SchemaCache by using a connection from the pool.
-loadSchemaCache :: AppState -> IO SCacheStatus
-loadSchemaCache appState = do
-  conf@AppConfig{..} <- getConfig appState
-  result <-
-    let transaction = if configDbPreparedStatements then SQL.transaction else SQL.unpreparedTransaction in
-    usePool appState . transaction SQL.ReadCommitted SQL.Read $
-      querySchemaCache conf
-  case result of
-    Left e -> do
-      case checkIsFatal e of
-        Just hint -> do
-          logWithZTime appState "A fatal error ocurred when loading the schema cache"
-          logPgrstError appState e
-          logWithZTime appState hint
-          return SCFatalFail
-        Nothing -> do
-          putSchemaCache appState Nothing
-          logWithZTime appState "An error ocurred when loading the schema cache"
-          logPgrstError appState e
-          return SCOnRetry
-
-    Right sCache -> do
-      putSchemaCache appState (Just sCache)
-      logWithZTime appState "Schema cache loaded"
-      return SCLoaded
-
-- | Current database connection status data ConnectionStatus
-data ConnectionStatus
-  = NotConnected
-  | Connected PgVersion
-  | FatalConnectionError Text
-  deriving (Eq)
-
-- | The purpose of this worker is to obtain a healthy connection to pg and an
-- up-to-date schema cache(SchemaCache).  This method is meant to be called
-- multiple times by the same thread, but does nothing if the previous
-- invocation has not terminated. In all cases this method does not halt the
-- calling thread, the work is performed in a separate thread.
--
-- Background thread that does the following :
--  1. Tries to connect to pg server and will keep trying until success.
--  2. Checks if the pg version is supported and if it's not it kills the main
--     program.
--  3. Obtains the sCache. If this fails, it goes back to 1.
-internalConnectionWorker :: AppState -> IO ()
-internalConnectionWorker appState = work
-  where
-    work = do
-      AppConfig{..} <- getConfig appState
-      logWithZTime appState $ "Starting PostgREST " <> T.decodeUtf8 prettyVersion <> "..."
-      logWithZTime appState "Attempting to connect to the database..."
-      connected <- establishConnection appState
-      case connected of
-        FatalConnectionError reason ->
-          -- Fatal error when connecting
-          logWithZTime appState reason >> killThread (getMainThreadId appState)
-        NotConnected ->
-          -- Unreachable because establishConnection will keep trying to connect
-          return ()
-        Connected actualPgVersion -> do
-          -- Procede with initialization
-          putPgVersion appState actualPgVersion
-          when configDbChannelEnabled $
-            signalListener appState
-          logWithZTime appState "Connection successful"
-          -- this could be fail because the connection drops, but the loadSchemaCache will pick the error and retry again
-          -- We cannot retry after it fails immediately, because db-pre-config could have user errors. We just log the error and continue.
-          when configDbConfig $ reReadConfig False appState
-          scStatus <- loadSchemaCache appState
-          case scStatus of
-            SCLoaded ->
-              -- do nothing and proceed if the load was successful
-              return ()
-            SCOnRetry ->
-              -- retry reloading the schema cache
-              work
-            SCFatalFail ->
-              -- die if our schema cache query has an error
-              killThread $ getMainThreadId appState
-
-- | Repeatedly flush the pool, and check if a connection from the
-- pool allows access to the PostgreSQL database.
--
-- Releasing the pool is key for rapid recovery. Otherwise, the pool
-- timeout would have to be reached for new healthy connections to be acquired.
-- Which might not happen if the server is busy with requests. No idle
-- connection, no pool timeout.
--
-- The connection tries are capped, but if the connection times out no error is
-- thrown, just 'False' is returned.
-establishConnection :: AppState -> IO ConnectionStatus
-establishConnection appState =
-  retrying retrySettings shouldRetry $
-    const $ flushPool appState >> getConnectionStatus
-  where
-    retrySettings = capDelay delayMicroseconds $ exponentialBackoff backoffMicroseconds
-    delayMicroseconds = 32000000 -- 32 seconds
-    backoffMicroseconds = 1000000 -- 1 second
-
-    getConnectionStatus :: IO ConnectionStatus
-    getConnectionStatus = do
-      pgVersion <- usePool appState $ queryPgVersion False -- No need to prepare the query here, as the connection might not be established
-      case pgVersion of
-        Left e -> do
-          logPgrstError appState e
-          case checkIsFatal e of
-            Just reason ->
-              return $ FatalConnectionError reason
-            Nothing ->
-              return NotConnected
-        Right version ->
-          if version < minimumPgVersion then
-            return . FatalConnectionError $
-              "Cannot run in this PostgreSQL version, PostgREST needs at least "
-              <> pgvName minimumPgVersion
-          else
-            return . Connected  $ version
-
-    shouldRetry :: RetryStatus -> ConnectionStatus -> IO Bool
-    shouldRetry rs isConnSucc = do
-      let
-        delay = fromMaybe 0 (rsPreviousDelay rs) `div` backoffMicroseconds
-        itShould = NotConnected == isConnSucc
-      when itShould . logWithZTime appState $
-        "Attempting to reconnect to the database in "
-        <> (show delay::Text)
-        <> " seconds..."
-      when itShould $ putRetryNextIn appState delay
-      return itShould
-
-- | Re-reads the config plus config options from the db
-reReadConfig :: Bool -> AppState -> IO ()
-reReadConfig startingUp appState = do
-  AppConfig{..} <- getConfig appState
-  dbSettings <-
-    if configDbConfig then do
-      qDbSettings <- usePool appState $ queryDbSettings (dumpQi <$> configDbPreConfig) configDbPreparedStatements
-      case qDbSettings of
-        Left e -> do
-          logWithZTime appState
-            "An error ocurred when trying to query database settings for the config parameters"
-          case checkIsFatal e of
-            Just hint -> do
-              logPgrstError appState e
-              logWithZTime appState hint
-              killThread (getMainThreadId appState)
-            Nothing -> do
-              logPgrstError appState e
-          pure mempty
-        Right x -> pure x
-    else
-      pure mempty
-  (roleSettings, roleIsolationLvl) <-
-    if configDbConfig then do
-      rSettings <- usePool appState $ queryRoleSettings configDbPreparedStatements
-      case rSettings of
-        Left e -> do
-          logWithZTime appState "An error ocurred when trying to query the role settings"
-          logPgrstError appState e
-          pure (mempty, mempty)
-        Right x -> pure x
-    else
-      pure mempty
-  readAppConfig dbSettings configFilePath (Just configDbUri) roleSettings roleIsolationLvl >>= \case
-    Left err   ->
-      if startingUp then
-        panic err -- die on invalid config if the program is starting up
-      else
-        logWithZTime appState $ "Failed reloading config: " <> err
-    Right newConf -> do
-      putConfig appState newConf
-      if startingUp then
-        pass
-      else
-        logWithZTime appState "Config reloaded"
-
-
-runListener :: AppConfig -> AppState -> IO ()
-runListener AppConfig{configDbChannelEnabled} appState =
-  when configDbChannelEnabled $ listener appState
-
-- | Starts a dedicated pg connection to LISTEN for notifications.  When a
-- NOTIFY <db-channel> - with an empty payload - is done, it refills the schema
-- cache.  It uses the connectionWorker in case the LISTEN connection dies.
-listener :: AppState -> IO ()
-listener appState = do
-  AppConfig{..} <- getConfig appState
-  let dbChannel = toS configDbChannel
-
-  -- The listener has to wait for a signal from the connectionWorker.
-  -- This is because when the connection to the db is lost, the listener also
-  -- tries to recover the connection, but not with the same pace as the connectionWorker.
-  -- Not waiting makes stderr quickly fill with connection retries messages from the listener.
-  waitListener appState
-
-  -- forkFinally allows to detect if the thread dies
-  void . flip forkFinally (handleFinally dbChannel) $ do
-    dbOrError <- acquire $ toUtf8 (addFallbackAppName prettyVersion configDbUri)
-    case dbOrError of
-      Right db -> do
-        logWithZTime appState $ "Listening for notifications on the " <> dbChannel <> " channel"
-        putIsListenerOn appState True
-        SQL.listen db $ SQL.toPgIdentifier dbChannel
-        SQL.waitForNotifications handleNotification db
-      _ ->
-        die $ "Could not listen for notifications on the " <> dbChannel <> " channel"
-  where
-    handleFinally dbChannel _ = do
-      -- if the thread dies, we try to recover
-      logWithZTime appState $ "Retrying listening for notifications on the " <> dbChannel <> " channel.."
-      putIsListenerOn appState False
-      -- assume the pool connection was also lost, call the connection worker
-      connectionWorker appState
-      -- retry the listener
-      listener appState
-
-    handleNotification _ msg
-      | BS.null msg            = cacheReloader
-      | msg == "reload schema" = cacheReloader
-      | msg == "reload config" = reReadConfig False appState
-      | otherwise              = pure () -- Do nothing if anything else than an empty message is sent
-
-    cacheReloader =
-      -- reloads the schema cache + restarts pool connections
-      -- it's necessary to restart the pg connections because they cache the pg catalog(see #2620)
-      connectionWorker appState
-
-checkIsFatal :: SQL.UsageError -> Maybe Text
-checkIsFatal (SQL.ConnectionUsageError e)
-  | isAuthFailureMessage = Just $ toS failureMessage
-  | otherwise = Nothing
-  where isAuthFailureMessage =
-          ("FATAL:  password authentication failed" `isInfixOf` failureMessage) ||
-          ("no password supplied" `isInfixOf` failureMessage)
-        failureMessage = BS.unpack $ fromMaybe mempty e
-checkIsFatal(SQL.SessionUsageError (SQL.QueryError _ _ (SQL.ResultError serverError)))
-  = case serverError of
-      -- Check for a syntax error (42601 is the pg code). This would mean the error is on our part somehow, so we treat it as fatal.
-      SQL.ServerError "42601" _ _ _ _
-        -> Just "Hint: This is probably a bug in PostgREST, please report it at https://github.com/PostgREST/postgrest/issues"
-      -- Check for a "prepared statement <name> already exists" error (Code 42P05: duplicate_prepared_statement).
-      -- This would mean that a connection pooler in transaction mode is being used
-      -- while prepared statements are enabled in the PostgREST configuration,
-      -- both of which are incompatible with each other.
-      SQL.ServerError "42P05" _ _ _ _
-        -> Just "Hint: If you are using connection poolers in transaction mode, try setting db-prepared-statements to false."
-      -- Check for a "transaction blocks not allowed in statement pooling mode" error (Code 08P01: protocol_violation).
-      -- This would mean that a connection pooler in statement mode is being used which is not supported in PostgREST.
-      SQL.ServerError "08P01" "transaction blocks not allowed in statement pooling mode" _ _ _
-        -> Just "Hint: Connection poolers in statement mode are not supported."
-      _ -> Nothing
-checkIsFatal _ = Nothing
@@ -12,58 +12,43 @@ very simple authentication system inside the PostgreSQL database.
 -}
 {-# LANGUAGE RecordWildCards #-}
 module PostgREST.Auth
-  ( AuthResult (..)
-  , getResult
-  , getRole
-  , middleware
+  ( containsRole
+  , jwtClaims
+  , JWTClaims
  ) where

-import qualified Crypto.JWT                      as JWT
-import qualified Data.Aeson                      as JSON
-import qualified Data.Aeson.Key                  as K
-import qualified Data.Aeson.KeyMap               as KM
-import qualified Data.Aeson.Types                as JSON
-import qualified Data.ByteString                 as BS
-import qualified Data.ByteString.Lazy.Char8      as LBS
-import qualified Data.Vault.Lazy                 as Vault
-import qualified Data.Vector                     as V
-import qualified Network.HTTP.Types.Header       as HTTP
-import qualified Network.Wai                     as Wai
-import qualified Network.Wai.Middleware.HttpAuth as Wai
+import qualified Crypto.JWT          as JWT
+import qualified Data.Aeson          as JSON
+import qualified Data.HashMap.Strict as M
+import qualified Data.Vector         as V

 import Control.Lens            (set)
 import Control.Monad.Except    (liftEither)
 import Data.Either.Combinators (mapLeft)
-import Data.List               (lookup)
 import Data.Time.Clock         (UTCTime)
-import System.IO.Unsafe        (unsafePerformIO)

-import PostgREST.AppState (AppState, getConfig, getTime)
-import PostgREST.Config   (AppConfig (..), JSPath, JSPathExp (..))
-import PostgREST.Error    (Error (..))
+import PostgREST.Config (AppConfig (..), JSPath, JSPathExp (..))
+import PostgREST.Error  (Error (..))

 import Protolude


-data AuthResult = AuthResult
-  { authClaims :: KM.KeyMap JSON.Value
-  , authRole   :: BS.ByteString
-  }
+type JWTClaims = M.HashMap Text JSON.Value

 -- | Receives the JWT secret and audience (from config) and a JWT and returns a
-- JSON object of JWT claims.
-parseToken :: Monad m =>
-  AppConfig -> LByteString -> UTCTime -> ExceptT Error m JSON.Value
-parseToken _ "" _ = return JSON.emptyObject
-parseToken AppConfig{..} token time = do
+-- map of JWT claims.
+jwtClaims :: Monad m =>
+  AppConfig -> LByteString -> UTCTime -> ExceptT Error m JWTClaims
+jwtClaims _ "" _ = return M.empty
+jwtClaims AppConfig{..} payload time = do
  secret <- liftEither . maybeToRight JwtTokenMissing $ configJWKS
  eitherClaims <-
    lift . runExceptT $
-      JWT.verifyClaimsAt validation secret time =<< JWT.decodeCompact token
-  liftEither . mapLeft jwtClaimsError $ JSON.toJSON <$> eitherClaims
+      JWT.verifyClaimsAt validation secret time =<< JWT.decodeCompact payload
+  liftEither . mapLeft jwtClaimsError $ claimsMap configJwtRoleClaimKey <$> eitherClaims
  where
    validation =
-      JWT.defaultJWTValidationSettings audienceCheck & set JWT.allowedSkew 30
+      JWT.defaultJWTValidationSettings audienceCheck & set JWT.allowedSkew 1

    audienceCheck :: JWT.StringOrURI -> Bool
    audienceCheck = maybe (const True) (==) configJwtAudience
@@ -72,50 +57,26 @@ parseToken AppConfig{..} token time = do
    jwtClaimsError JWT.JWTExpired = JwtTokenInvalid "JWT expired"
    jwtClaimsError e              = JwtTokenInvalid $ show e

-parseClaims :: Monad m =>
-  AppConfig -> JSON.Value -> ExceptT Error m AuthResult
-parseClaims AppConfig{..} jclaims@(JSON.Object mclaims) = do
-  -- role defaults to anon if not specified in jwt
-  role <- liftEither . maybeToRight JwtTokenRequired $
-    unquoted <$> walkJSPath (Just jclaims) configJwtRoleClaimKey <|> configDbAnonRole
-  return AuthResult
-           { authClaims = mclaims & KM.insert "role" (JSON.toJSON $ decodeUtf8 role)
-           , authRole = role
-           }
+-- | Turn JWT ClaimSet into something easier to work with.
+--
+-- Also, here the jspath is applied to put the "role" in the map.
+claimsMap :: JSPath -> JWT.ClaimsSet -> JWTClaims
+claimsMap jspath claims =
+  case JSON.toJSON claims of
+    val@(JSON.Object o) ->
+      M.delete "role" o `M.union` role val
+    _ ->
+      M.empty
  where
+    role value =
+      maybe M.empty (M.singleton "role") $ walkJSPath (Just value) jspath
+
    walkJSPath :: Maybe JSON.Value -> JSPath -> Maybe JSON.Value
    walkJSPath x                      []                = x
-    walkJSPath (Just (JSON.Object o)) (JSPKey key:rest) = walkJSPath (KM.lookup (K.fromText key) o) rest
+    walkJSPath (Just (JSON.Object o)) (JSPKey key:rest) = walkJSPath (M.lookup key o) rest
    walkJSPath (Just (JSON.Array ar)) (JSPIdx idx:rest) = walkJSPath (ar V.!? idx) rest
    walkJSPath _                      _                 = Nothing

-    unquoted :: JSON.Value -> BS.ByteString
-    unquoted (JSON.String t) = encodeUtf8 t
-    unquoted v               = LBS.toStrict $ JSON.encode v
-- impossible case - just added to please -Wincomplete-patterns
-parseClaims _ _ = return AuthResult { authClaims = KM.empty, authRole = mempty }
-
-- | Validate authorization header.
--   Parse and store JWT claims for future use in the request.
-middleware :: AppState -> Wai.Middleware
-middleware appState app req respond = do
-  conf <- getConfig appState
-  time <- getTime appState
-
-  let token = fromMaybe "" $ Wai.extractBearerAuth =<< lookup HTTP.hAuthorization (Wai.requestHeaders req)
-  authResult <- runExceptT $
-    parseToken conf (LBS.fromStrict token) time >>=
-    parseClaims conf
-
-  let req' = req { Wai.vault = Wai.vault req & Vault.insert authResultKey authResult }
-  app req' respond
-
-authResultKey :: Vault.Key (Either Error AuthResult)
-authResultKey = unsafePerformIO Vault.newKey
-{-# NOINLINE authResultKey #-}
-
-getResult :: Wai.Request -> Maybe (Either Error AuthResult)
-getResult = Vault.lookup authResultKey . Wai.vault
-
-getRole :: Wai.Request -> Maybe BS.ByteString
-getRole req = authRole <$> (rightToMaybe =<< getResult req)
+-- | Whether a response from jwtClaims contains a role claim
+containsRole :: JWTClaims -> Bool
+containsRole = M.member "role"
@@ -11,6 +11,7 @@ module PostgREST.CLI
 import qualified Data.Aeson                 as JSON
 import qualified Data.ByteString.Char8      as BS
 import qualified Data.ByteString.Lazy       as LBS
+import qualified Hasql.Pool                 as SQL
 import qualified Hasql.Transaction.Sessions as SQL
 import qualified Options.Applicative        as O

@@ -19,8 +20,9 @@ import Text.Heredoc (str)

 import PostgREST.AppState    (AppState)
 import PostgREST.Config      (AppConfig (..))
-import PostgREST.SchemaCache (querySchemaCache)
+import PostgREST.DbStructure (queryDbStructure)
 import PostgREST.Version     (prettyVersion)
+import PostgREST.Workers     (reReadConfig)

 import qualified PostgREST.App      as App
 import qualified PostgREST.AppState as AppState
@@ -32,35 +34,39 @@ import Protolude hiding (hPutStrLn)
 main :: App.SignalHandlerInstaller -> Maybe App.SocketRunner -> CLI -> IO ()
 main installSignalHandlers runAppWithSocket CLI{cliCommand, cliPath} = do
  conf@AppConfig{..} <-
-    either panic identity <$> Config.readAppConfig mempty cliPath Nothing mempty mempty
+    either panic identity <$> Config.readAppConfig mempty cliPath Nothing
+  appState <- AppState.init conf

-  -- Per https://github.com/PostgREST/postgrest/issues/268, we want to
-  -- explicitly close the connections to PostgreSQL on shutdown.
-  -- 'AppState.destroy' takes care of that.
-  bracket
-    (AppState.init conf)
-    AppState.destroy
-    (\appState -> case cliCommand of
-      CmdDumpConfig -> do
-        when configDbConfig $ AppState.reReadConfig True appState
-        putStr . Config.toText =<< AppState.getConfig appState
-      CmdDumpSchema -> putStrLn =<< dumpSchema appState
-      CmdRun -> App.run installSignalHandlers runAppWithSocket appState)
+  -- Override the config with config options from the db
+  -- TODO: the same operation is repeated on connectionWorker, ideally this
+  -- would be done only once, but dump CmdDumpConfig needs it for tests.
+  when configDbConfig $ reReadConfig True appState

-- | Dump SchemaCache schema to JSON
+  exec cliCommand appState
+  where
+    exec :: Command -> AppState -> IO ()
+    exec CmdDumpConfig appState = putStr . Config.toText =<< AppState.getConfig appState
+    exec CmdDumpSchema appState = putStrLn =<< dumpSchema appState
+    exec CmdRun appState = App.run installSignalHandlers runAppWithSocket appState
+
+-- | Dump DbStructure schema to JSON
 dumpSchema :: AppState -> IO LBS.ByteString
 dumpSchema appState = do
-  conf@AppConfig{..} <- AppState.getConfig appState
+  AppConfig{..} <- AppState.getConfig appState
  result <-
    let transaction = if configDbPreparedStatements then SQL.transaction else SQL.unpreparedTransaction in
-    AppState.usePool appState $
+    SQL.use (AppState.getPool appState) $
      transaction SQL.ReadCommitted SQL.Read $
-        querySchemaCache conf
+        queryDbStructure
+          (toList configDbSchemas)
+          configDbExtraSearchPath
+          configDbPreparedStatements
+  SQL.release $ AppState.getPool appState
  case result of
    Left e -> do
      hPutStrLn stderr $ "An error ocurred when loading the schema cache:\n" <> show e
      exitFailure
-    Right sCache -> return $ JSON.encode sCache
+    Right dbStructure -> return $ JSON.encode dbStructure

 -- | Command line interface options
 data CLI = CLI
@@ -74,13 +80,13 @@ data Command
  | CmdDumpSchema

 -- | Read command line interface options. Also prints help.
-readCLIShowHelp :: IO CLI
-readCLIShowHelp =
+readCLIShowHelp :: Bool -> IO CLI
+readCLIShowHelp hasEnvironment =
  O.customExecParser prefs opts
  where
    prefs = O.prefs $ O.showHelpOnError <> O.showHelpOnEmpty
-    opts = O.info parser $ O.fullDesc <> progDesc
-    parser = O.helper <*> versionFlag <*> exampleParser <*> cliParser
+    opts = O.info parser $ O.fullDesc <> progDesc <> footer
+    parser = O.helper <*> exampleParser <*> cliParser

    progDesc =
      O.progDesc $
@@ -88,11 +94,10 @@ readCLIShowHelp =
        <> BS.unpack prettyVersion
        <> " / create a REST API to an existing Postgres database"

-    versionFlag =
-      O.infoOption ("PostgREST " <> BS.unpack prettyVersion) $
-        O.long "version"
-        <> O.short 'v'
-        <> O.help "Show the version information"
+    footer =
+      O.footer $
+        "To run PostgREST, please pass the FILENAME argument"
+        <> " or set PGRST_ environment variables."

    exampleParser =
      O.infoOption exampleConfigFile $
@@ -104,12 +109,12 @@ readCLIShowHelp =
    cliParser =
      CLI
        <$> (dumpConfigFlag <|> dumpSchemaFlag)
-        <*> O.optional configFileOption
+        <*> optionalIf hasEnvironment configFileOption

    configFileOption =
      O.strArgument $
        O.metavar "FILENAME"
-        <> O.help "Path to configuration file"
+        <> O.help "Path to configuration file (optional with PGRST_ environment variables)"

    dumpConfigFlag =
      O.flag CmdRun CmdDumpConfig $
@@ -121,13 +126,36 @@ readCLIShowHelp =
        O.long "dump-schema"
        <> O.help "Dump loaded schema as JSON and exit (for debugging, output structure is unstable)"

+    optionalIf :: Alternative f => Bool -> f a -> f (Maybe a)
+    optionalIf True  = O.optional
+    optionalIf False = fmap Just
+
 exampleConfigFile :: [Char]
 exampleConfigFile =
-  [str|## Admin server used for checks. It's disabled by default unless a port is specified.
-      |# admin-server-port = 3001
+  [str|### REQUIRED:
+      |db-uri = "postgres://user:pass@localhost:5432/dbname"
+      |db-schema = "public"
+      |db-anon-role = "postgres"
      |
-      |## The database role to use when no client authentication is provided
-      |# db-anon-role = "anon"
+      |### OPTIONAL:
+      |## number of open connections in the pool
+      |db-pool = 10
+      |
+      |## Time to live, in seconds, for an idle database pool connection.
+      |db-pool-timeout = 10
+      |
+      |## extra schemas to add to the search_path of every request
+      |db-extra-search-path = "public"
+      |
+      |## limit rows in response
+      |# db-max-rows = 1000
+      |
+      |## stored proc to exec immediately after auth
+      |# db-pre-request = "stored_proc_name"
+      |
+      |## stored proc that overrides the root "/" spec
+      |## it must be inside the db-schema
+      |# db-root-spec = "stored_proc_name"
      |
      |## Notification channel for reloading the schema cache
      |db-channel = "pgrst"
@@ -138,91 +166,56 @@ exampleConfigFile =
      |## Enable in-database configuration
      |db-config = true
      |
-      |## Function for in-database configuration
-      |## db-pre-config = "postgrest.pre_config"
-      |
-      |## Extra schemas to add to the search_path of every request
-      |db-extra-search-path = "public"
-      |
-      |## Limit rows in response
-      |# db-max-rows = 1000
-      |
-      |## Allow getting the EXPLAIN plan through the `Accept: application/vnd.pgrst.plan` header
-      |# db-plan-enabled = false
-      |
-      |## Number of open connections in the pool
-      |db-pool = 10
-      |
-      |## Time in seconds to wait to acquire a slot from the connection pool
-      |# db-pool-acquisition-timeout = 10
-      |
-      |## Time in seconds after which to recycle pool connections
-      |# db-pool-max-lifetime = 1800
-      |
-      |## Time in seconds after which to recycle unused pool connections
-      |# db-pool-max-idletime = 30
-      |
-      |## Stored proc to exec immediately after auth
-      |# db-pre-request = "stored_proc_name"
-      |
-      |## Enable or disable prepared statements. disabling is only necessary when behind a connection pooler.
-      |## When disabled, statements will be parametrized but won't be prepared.
-      |db-prepared-statements = true
-      |
-      |## The name of which database schema to expose to REST clients
-      |db-schemas = "public"
-      |
-      |## How to terminate database transactions
-      |## Possible values are:
-      |## commit (default)
-      |##   Transaction is always committed, this can not be overriden
-      |## commit-allow-override
-      |##   Transaction is committed, but can be overriden with Prefer tx=rollback header
-      |## rollback
-      |##   Transaction is always rolled back, this can not be overriden
-      |## rollback-allow-override
-      |##   Transaction is rolled back, but can be overriden with Prefer tx=commit header
-      |db-tx-end = "commit"
-      |
-      |## The standard connection URI format, documented at
-      |## https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNSTRING
-      |db-uri = "postgresql://"
-      |
      |## Determine if GUC request settings for headers, cookies and jwt claims use the legacy names (string with dashes, invalid starting from PostgreSQL v14) with text values instead of the new names (string without dashes, valid on all PostgreSQL versions) with json values.
      |## For PostgreSQL v14 and up, this setting will be ignored.
      |db-use-legacy-gucs = true
      |
-      |# jwt-aud = "your_audience_claim"
+      |## how to terminate database transactions
+      |## possible values are:
+      |## commit (default)
+      |##   transaction is always committed, this can not be overriden
+      |## commit-allow-override
+      |##   transaction is committed, but can be overriden with Prefer tx=rollback header
+      |## rollback
+      |##   transaction is always rolled back, this can not be overriden
+      |## rollback-allow-override
+      |##   transaction is rolled back, but can be overriden with Prefer tx=commit header
+      |db-tx-end = "commit"
      |
-      |## Jspath to the role claim key
-      |jwt-role-claim-key = ".role"
-      |
-      |## Choose a secret, JSON Web Key (or set) to enable JWT auth
-      |## (use "@filename" to load from separate file)
-      |# jwt-secret = "secret_with_at_least_32_characters"
-      |jwt-secret-is-base64 = false
-      |
-      |## Logging level, the admitted values are: crit, error, warn and info.
-      |log-level = "error"
-      |
-      |## Determine if the OpenAPI output should follow or ignore role privileges or be disabled entirely.
-      |## Admitted values: follow-privileges, ignore-privileges, disabled
-      |openapi-mode = "follow-privileges"
-      |
-      |## Base url for the OpenAPI output
-      |openapi-server-proxy-uri = ""
-      |
-      |## Content types to produce raw output
-      |# raw-media-types="image/png, image/jpg"
+      |## enable or disable prepared statements. disabling is only necessary when behind a connection pooler.
+      |## when disabled, statements will be parametrized but won't be prepared.
+      |db-prepared-statements = true
      |
      |server-host = "!4"
      |server-port = 3000
      |
-      |## Unix socket location
+      |## unix socket location
      |## if specified it takes precedence over server-port
      |# server-unix-socket = "/tmp/pgrst.sock"
      |
-      |## Unix socket file mode
-      |## When none is provided, 660 is applied by default
+      |## unix socket file mode
+      |## when none is provided, 660 is applied by default
      |# server-unix-socket-mode = "660"
+      |
+      |## determine if the OpenAPI output should follow or ignore role privileges or be disabled entirely
+      |## admitted values: follow-privileges, ignore-privileges, disabled
+      |openapi-mode = "follow-privileges"
+      |
+      |## base url for the OpenAPI output
+      |openapi-server-proxy-uri = ""
+      |
+      |## choose a secret, JSON Web Key (or set) to enable JWT auth
+      |## (use "@filename" to load from separate file)
+      |# jwt-secret = "secret_with_at_least_32_characters"
+      |# jwt-aud = "your_audience_claim"
+      |jwt-secret-is-base64 = false
+      |
+      |## jspath to the role claim key
+      |jwt-role-claim-key = ".role"
+      |
+      |## content types to produce raw output
+      |# raw-media-types="image/png, image/jpg"
+      |
+      |## logging level, the admitted values are: crit, error, warn and info.
+      |log-level = "error"
      |]
@@ -24,7 +24,6 @@ module PostgREST.Config
  , readPGRSTEnvironment
  , toURI
  , parseSecret
-  , addFallbackAppName
  ) where

 import qualified Crypto.JOSE.Types      as JOSE
@@ -33,7 +32,6 @@ import qualified Data.Aeson             as JSON
 import qualified Data.ByteString        as BS
 import qualified Data.ByteString.Base64 as B64
 import qualified Data.ByteString.Lazy   as LBS
-import qualified Data.CaseInsensitive   as CI
 import qualified Data.Configurator      as C
 import qualified Data.Map.Strict        as M
 import qualified Data.Text              as T
@@ -48,68 +46,53 @@ import Data.List               (lookup)
 import Data.List.NonEmpty      (fromList, toList)
 import Data.Maybe              (fromJust)
 import Data.Scientific         (floatingOrInteger)
-import Network.URI             (escapeURIString,
-                                isUnescapedInURIComponent, parseURI,
-                                uriQuery)
+import Data.Time.Clock         (NominalDiffTime)
 import Numeric                 (readOct, showOct)
 import System.Environment      (getEnvironment)
 import System.Posix.Types      (FileMode)

-import PostgREST.Config.Database         (RoleIsolationLvl,
-                                          RoleSettings)
 import PostgREST.Config.JSPath           (JSPath, JSPathExp (..),
                                          dumpJSPath, pRoleClaimKey)
 import PostgREST.Config.Proxy            (Proxy (..),
                                          isMalformedProxyUri, toURI)
-import PostgREST.MediaType               (MediaType (..), toMime)
-import PostgREST.SchemaCache.Identifiers (QualifiedIdentifier, dumpQi,
+import PostgREST.DbStructure.Identifiers (QualifiedIdentifier, dumpQi,
                                          toQi)

 import Protolude hiding (Proxy, toList)


 data AppConfig = AppConfig
-  { configAppSettings              :: [(Text, Text)]
-  , configDbAnonRole               :: Maybe BS.ByteString
-  , configDbChannel                :: Text
-  , configDbChannelEnabled         :: Bool
-  , configDbExtraSearchPath        :: [Text]
-  , configDbMaxRows                :: Maybe Integer
-  , configDbPlanEnabled            :: Bool
-  , configDbPoolSize               :: Int
-  , configDbPoolAcquisitionTimeout :: Int
-  , configDbPoolMaxLifetime        :: Int
-  , configDbPoolMaxIdletime        :: Int
-  , configDbPreRequest             :: Maybe QualifiedIdentifier
-  , configDbPreparedStatements     :: Bool
-  , configDbRootSpec               :: Maybe QualifiedIdentifier
-  , configDbSchemas                :: NonEmpty Text
-  , configDbConfig                 :: Bool
-  , configDbPreConfig              :: Maybe QualifiedIdentifier
-  , configDbTxAllowOverride        :: Bool
-  , configDbTxRollbackAll          :: Bool
-  , configDbUri                    :: Text
-  , configDbUseLegacyGucs          :: Bool
-  , configFilePath                 :: Maybe FilePath
-  , configJWKS                     :: Maybe JWKSet
-  , configJwtAudience              :: Maybe StringOrURI
-  , configJwtRoleClaimKey          :: JSPath
-  , configJwtSecret                :: Maybe BS.ByteString
-  , configJwtSecretIsBase64        :: Bool
-  , configLogLevel                 :: LogLevel
-  , configOpenApiMode              :: OpenAPIMode
-  , configOpenApiSecurityActive    :: Bool
-  , configOpenApiServerProxyUri    :: Maybe Text
-  , configRawMediaTypes            :: [MediaType]
-  , configServerHost               :: Text
-  , configServerPort               :: Int
-  , configServerTraceHeader        :: Maybe (CI.CI BS.ByteString)
-  , configServerUnixSocket         :: Maybe FilePath
-  , configServerUnixSocketMode     :: FileMode
-  , configAdminServerPort          :: Maybe Int
-  , configRoleSettings             :: RoleSettings
-  , configRoleIsoLvl               :: RoleIsolationLvl
-  , configInternalSCSleep          :: Maybe Int32
+  { configAppSettings           :: [(Text, Text)]
+  , configDbAnonRole            :: Text
+  , configDbChannel             :: Text
+  , configDbChannelEnabled      :: Bool
+  , configDbExtraSearchPath     :: [Text]
+  , configDbMaxRows             :: Maybe Integer
+  , configDbPoolSize            :: Int
+  , configDbPoolTimeout         :: NominalDiffTime
+  , configDbPreRequest          :: Maybe QualifiedIdentifier
+  , configDbPreparedStatements  :: Bool
+  , configDbRootSpec            :: Maybe QualifiedIdentifier
+  , configDbSchemas             :: NonEmpty Text
+  , configDbConfig              :: Bool
+  , configDbTxAllowOverride     :: Bool
+  , configDbTxRollbackAll       :: Bool
+  , configDbUri                 :: Text
+  , configDbUseLegacyGucs       :: Bool
+  , configFilePath              :: Maybe FilePath
+  , configJWKS                  :: Maybe JWKSet
+  , configJwtAudience           :: Maybe StringOrURI
+  , configJwtRoleClaimKey       :: JSPath
+  , configJwtSecret             :: Maybe BS.ByteString
+  , configJwtSecretIsBase64     :: Bool
+  , configLogLevel              :: LogLevel
+  , configOpenApiMode           :: OpenAPIMode
+  , configOpenApiServerProxyUri :: Maybe Text
+  , configRawMediaTypes         :: [BS.ByteString]
+  , configServerHost            :: Text
+  , configServerPort            :: Int
+  , configServerUnixSocket      :: Maybe FilePath
+  , configServerUnixSocketMode  :: FileMode
  }

 data LogLevel = LogCrit | LogError | LogWarn | LogInfo
@@ -137,22 +120,18 @@ toText conf =
  where
    -- apply conf to all pgrst settings
    pgrstSettings = (\(k, v) -> (k, v conf)) <$>
-      [("db-anon-role",              q . T.decodeUtf8 . fromMaybe "" . configDbAnonRole)
+      [("db-anon-role",              q . configDbAnonRole)
      ,("db-channel",                q . configDbChannel)
      ,("db-channel-enabled",            T.toLower . show . configDbChannelEnabled)
      ,("db-extra-search-path",      q . T.intercalate "," . configDbExtraSearchPath)
      ,("db-max-rows",                   maybe "\"\"" show . configDbMaxRows)
-      ,("db-plan-enabled",               T.toLower . show . configDbPlanEnabled)
      ,("db-pool",                       show . configDbPoolSize)
-      ,("db-pool-acquisition-timeout",   show . configDbPoolAcquisitionTimeout)
-      ,("db-pool-max-lifetime",          show . configDbPoolMaxLifetime)
-      ,("db-pool-max-idletime",          show . configDbPoolMaxIdletime)
+      ,("db-pool-timeout",               show . floor . configDbPoolTimeout)
      ,("db-pre-request",            q . maybe mempty dumpQi . configDbPreRequest)
      ,("db-prepared-statements",        T.toLower . show . configDbPreparedStatements)
      ,("db-root-spec",              q . maybe mempty dumpQi . configDbRootSpec)
      ,("db-schemas",                q . T.intercalate "," . toList . configDbSchemas)
      ,("db-config",                     T.toLower . show . configDbConfig)
-      ,("db-pre-config",             q . maybe mempty dumpQi . configDbPreConfig)
      ,("db-tx-end",                 q . showTxEnd)
      ,("db-uri",                    q . configDbUri)
      ,("db-use-legacy-gucs",            T.toLower . show . configDbUseLegacyGucs)
@@ -162,15 +141,12 @@ toText conf =
      ,("jwt-secret-is-base64",          T.toLower . show . configJwtSecretIsBase64)
      ,("log-level",                 q . dumpLogLevel . configLogLevel)
      ,("openapi-mode",              q . dumpOpenApiMode . configOpenApiMode)
-      ,("openapi-security-active",       T.toLower . show . configOpenApiSecurityActive)
      ,("openapi-server-proxy-uri",  q . fromMaybe mempty . configOpenApiServerProxyUri)
-      ,("raw-media-types",           q . T.decodeUtf8 . BS.intercalate "," . fmap toMime . configRawMediaTypes)
+      ,("raw-media-types",           q . T.decodeUtf8 . BS.intercalate "," . configRawMediaTypes)
      ,("server-host",               q . configServerHost)
      ,("server-port",                   show . configServerPort)
-      ,("server-trace-header",       q . T.decodeUtf8 . maybe mempty CI.original . configServerTraceHeader)
      ,("server-unix-socket",        q . maybe mempty T.pack . configServerUnixSocket)
      ,("server-unix-socket-mode",   q . T.pack . showSocketMode)
-      ,("admin-server-port",             maybe "\"\"" show . configAdminServerPort)
      ]

    -- quote all app.settings
@@ -197,20 +173,20 @@ class JustIfMaybe a b where
  justIfMaybe :: a -> b

 instance JustIfMaybe a a where
-  justIfMaybe = identity
+  justIfMaybe a = a

 instance JustIfMaybe a (Maybe a) where
-  justIfMaybe = Just
+  justIfMaybe a = Just a

 -- | Reads and parses the config and overrides its parameters from env vars,
 -- files or db settings.
-readAppConfig :: [(Text, Text)] -> Maybe FilePath -> Maybe Text -> RoleSettings -> RoleIsolationLvl -> IO (Either Text AppConfig)
-readAppConfig dbSettings optPath prevDbUri roleSettings roleIsolationLvl = do
+readAppConfig :: [(Text, Text)] -> Maybe FilePath -> Maybe Text -> IO (Either Text AppConfig)
+readAppConfig dbSettings optPath prevDbUri = do
  env <- readPGRSTEnvironment
  -- if no filename provided, start with an empty map to read config from environment
  conf <- maybe (return $ Right M.empty) loadConfig optPath

-  case C.runParser (parser optPath env dbSettings roleSettings roleIsolationLvl) =<< mapLeft show conf of
+  case C.runParser (parser optPath env dbSettings) =<< mapLeft show conf of
    Left err ->
      return . Left $ "Error in config " <> err
    Right parsedConfig ->
@@ -225,34 +201,30 @@ readAppConfig dbSettings optPath prevDbUri roleSettings roleIsolationLvl = do
      decodeJWKS <$>
        (decodeSecret =<< readSecretFile =<< readDbUriFile prevDbUri parsedConfig)

-parser :: Maybe FilePath -> Environment -> [(Text, Text)] -> RoleSettings -> RoleIsolationLvl -> C.Parser C.Config AppConfig
-parser optPath env dbSettings roleSettings roleIsolationLvl =
+parser :: Maybe FilePath -> Environment -> [(Text, Text)] -> C.Parser C.Config AppConfig
+parser optPath env dbSettings =
  AppConfig
    <$> parseAppSettings "app.settings"
-    <*> (fmap encodeUtf8 <$> optString "db-anon-role")
+    <*> reqString "db-anon-role"
    <*> (fromMaybe "pgrst" <$> optString "db-channel")
    <*> (fromMaybe True <$> optBool "db-channel-enabled")
    <*> (maybe ["public"] splitOnCommas <$> optValue "db-extra-search-path")
    <*> optWithAlias (optInt "db-max-rows")
                     (optInt "max-rows")
-    <*> (fromMaybe False <$> optBool "db-plan-enabled")
    <*> (fromMaybe 10 <$> optInt "db-pool")
-    <*> (fromMaybe 10 <$> optInt "db-pool-acquisition-timeout")
-    <*> (fromMaybe 1800 <$> optInt "db-pool-max-lifetime")
-    <*> (fromMaybe 30 <$> optWithAlias (optInt "db-pool-timeout")
-                                       (optInt "db-pool-max-idletime"))
+    <*> (fromIntegral . fromMaybe 10 <$> optInt "db-pool-timeout")
    <*> (fmap toQi <$> optWithAlias (optString "db-pre-request")
                                    (optString "pre-request"))
    <*> (fromMaybe True <$> optBool "db-prepared-statements")
    <*> (fmap toQi <$> optWithAlias (optString "db-root-spec")
                                    (optString "root-spec"))
-    <*> (fromList . maybe ["public"] splitOnCommas <$> optWithAlias (optValue "db-schemas")
-                                                                    (optValue "db-schema"))
+    <*> (fromList . splitOnCommas <$> reqWithAlias (optValue "db-schemas")
+                                                   (optValue "db-schema")
+                                                   "missing key: either db-schemas or db-schema must be set")
    <*> (fromMaybe True <$> optBool "db-config")
-    <*> (fmap toQi <$> optString "db-pre-config")
    <*> parseTxEnd "db-tx-end" snd
    <*> parseTxEnd "db-tx-end" fst
-    <*> (fromMaybe "postgresql://" <$> optString "db-uri")
+    <*> reqString "db-uri"
    <*> (fromMaybe True <$> optBool "db-use-legacy-gucs")
    <*> pure optPath
    <*> pure Nothing
@@ -264,18 +236,12 @@ parser optPath env dbSettings roleSettings roleIsolationLvl =
          (optBool "secret-is-base64"))
    <*> parseLogLevel "log-level"
    <*> parseOpenAPIMode "openapi-mode"
-    <*> (fromMaybe False <$> optBool "openapi-security-active")
    <*> parseOpenAPIServerProxyURI "openapi-server-proxy-uri"
-    <*> (maybe [] (fmap (MTOther . encodeUtf8) . splitOnCommas) <$> optValue "raw-media-types")
+    <*> (maybe [] (fmap encodeUtf8 . splitOnCommas) <$> optValue "raw-media-types")
    <*> (fromMaybe "!4" <$> optString "server-host")
    <*> (fromMaybe 3000 <$> optInt "server-port")
-    <*> (fmap (CI.mk . encodeUtf8) <$> optString "server-trace-header")
    <*> (fmap T.unpack <$> optString "server-unix-socket")
    <*> parseSocketFileMode "server-unix-socket-mode"
-    <*> optInt "admin-server-port"
-    <*> pure roleSettings
-    <*> pure roleIsolationLvl
-    <*> optInt "internal-schema-cache-sleep"
  where
    parseAppSettings :: C.Key -> C.Parser C.Config [(Text, Text)]
    parseAppSettings key = addFromEnv . fmap (fmap coerceText) <$> C.subassocs key C.value
@@ -348,12 +314,24 @@ parser optPath env dbSettings roleSettings roleIsolationLvl =
        Nothing  -> pure [JSPKey "role"]
        Just rck -> either (fail . show) pure $ pRoleClaimKey rck

+    reqWithAlias :: C.Parser C.Config (Maybe a) -> C.Parser C.Config (Maybe a) -> [Char] -> C.Parser C.Config a
+    reqWithAlias orig alias err =
+      orig >>= \case
+        Just v  -> pure v
+        Nothing ->
+          alias >>= \case
+            Just v  -> pure v
+            Nothing -> fail err
+
    optWithAlias :: C.Parser C.Config (Maybe a) -> C.Parser C.Config (Maybe a) -> C.Parser C.Config (Maybe a)
    optWithAlias orig alias =
      orig >>= \case
        Just v  -> pure $ Just v
        Nothing -> alias

+    reqString :: C.Key -> C.Parser C.Config Text
+    reqString k = overrideFromDbOrEnvironment C.required k coerceText
+
    optString :: C.Key -> C.Parser C.Config (Maybe Text)
    optString k = mfilter (/= "") <$> overrideFromDbOrEnvironment C.optional k coerceText

@@ -370,14 +348,20 @@ parser optPath env dbSettings roleSettings roleIsolationLvl =
                               (C.Key -> C.Parser C.Value a -> C.Parser C.Config b) ->
                               C.Key -> (C.Value -> a) -> C.Parser C.Config b
    overrideFromDbOrEnvironment necessity key coercion =
-      case dbConf <|> M.lookup envVarName env of
+      case reloadableDbSetting <|> M.lookup envVarName env of
        Just dbOrEnvVal -> pure $ justIfMaybe $ coercion $ C.String dbOrEnvVal
-        Nothing         -> necessity key (coercion <$> C.value)
+        Nothing  -> necessity key (coercion <$> C.value)
      where
        dashToUnderscore '-' = '_'
        dashToUnderscore c   = c
        envVarName = "PGRST_" <> (toUpper . dashToUnderscore <$> toS key)
-        dbConf = lookup (T.pack $ dashToUnderscore <$> toS key) dbSettings
+        reloadableDbSetting =
+          let dbSettingName = T.pack $ dashToUnderscore <$> toS key in
+          if dbSettingName `notElem` [
+            "server_host", "server_port", "server_unix_socket", "server_unix_socket_mode", "log_level",
+            "db_anon_role", "db_uri", "db_channel_enabled", "db_channel", "db_pool", "db_pool_timeout", "db_config"]
+          then lookup dbSettingName dbSettings
+          else Nothing

    coerceText :: C.Value -> Text
    coerceText (C.String s) = s
@@ -464,41 +448,3 @@ type Environment = M.Map [Char] Text
 readPGRSTEnvironment :: IO Environment
 readPGRSTEnvironment =
  M.map T.pack . M.fromList . filter (isPrefixOf "PGRST_" . fst) <$> getEnvironment
-
-- | Adds a `fallback_application_name` value to the connection string. This allows querying the PostgREST version on pg_stat_activity.
--
-- >>> let ver = "11.1.0 (5a04ec7)"::ByteString
-- >>> let strangeVer = "11'1&0@#$%,.:\"[]{}?+^()=asdfqwer"::ByteString
--
-- >>> addFallbackAppName ver "postgres://user:pass@host:5432/postgres"
-- "postgres://user:pass@host:5432/postgres?fallback_application_name=PostgREST%2011.1.0%20%285a04ec7%29"
--
-- >>> addFallbackAppName ver "postgres://user:pass@host:5432/postgres?"
-- "postgres://user:pass@host:5432/postgres?fallback_application_name=PostgREST%2011.1.0%20%285a04ec7%29"
--
-- >>> addFallbackAppName ver "postgres:///postgres?host=server&port=5432"
-- "postgres:///postgres?host=server&port=5432&fallback_application_name=PostgREST%2011.1.0%20%285a04ec7%29"
--
-- >>> addFallbackAppName ver "postgresql://"
-- "postgresql://?fallback_application_name=PostgREST%2011.1.0%20%285a04ec7%29"
--
-- >>> addFallbackAppName strangeVer "postgres:///postgres?host=server&port=5432"
-- "postgres:///postgres?host=server&port=5432&fallback_application_name=PostgREST%2011%271%260%40%23%24%25%2C.%3A%22%5B%5D%7B%7D%3F%2B%5E%28%29%3Dasdfqwer"
--
-- >>> addFallbackAppName ver "postgres://user:invalid_chars[]#@host:5432/postgres"
-- "postgres://user:invalid_chars[]#@host:5432/postgres"
--
-- >>> addFallbackAppName ver "invalid_uri1=val1 invalid_uri2=val2"
-- "invalid_uri1=val1 invalid_uri2=val2"
-addFallbackAppName :: ByteString -> Text -> Text
-addFallbackAppName version dbUri = dbUri <>
-  case uriQuery <$> parseURI (toS dbUri) of
-    -- Does not add the application name to key=val connection strings or invalid URIs
-    Nothing  -> mempty
-    Just ""  -> "?" <> uriFmt
-    Just "?" -> uriFmt
-    _        -> "&" <> uriFmt
-  where
-    uriFmt = pKeyWord <> toS (escapeURIString isUnescapedInURIComponent $ toS pgrstVer)
-    pKeyWord = "fallback_application_name="
-    pgrstVer = "PostgREST " <> T.decodeUtf8 version
@@ -3,194 +3,65 @@
 module PostgREST.Config.Database
  ( pgVersionStatement
  , queryDbSettings
-  , queryRoleSettings
  , queryPgVersion
-  , RoleSettings
-  , RoleIsolationLvl
-  , toIsolationLevel
  ) where

-import Control.Arrow ((***))
-
 import PostgREST.Config.PgVersion (PgVersion (..))

-import qualified Data.HashMap.Strict as HM
-
 import qualified Hasql.Decoders             as HD
 import qualified Hasql.Encoders             as HE
+import qualified Hasql.Pool                 as SQL
 import           Hasql.Session              (Session, statement)
 import qualified Hasql.Statement            as SQL
 import qualified Hasql.Transaction          as SQL
 import qualified Hasql.Transaction.Sessions as SQL

-import Text.InterpolatedString.Perl6 (q, qc)
+import Text.InterpolatedString.Perl6 (q)

 import Protolude

-type RoleSettings     = (HM.HashMap ByteString (HM.HashMap ByteString ByteString))
-type RoleIsolationLvl = HM.HashMap ByteString SQL.IsolationLevel
+queryPgVersion :: Session PgVersion
+queryPgVersion = statement mempty pgVersionStatement

-toIsolationLevel :: (Eq a, IsString a) => a -> SQL.IsolationLevel
-toIsolationLevel a = case a of
-  "repeatable read" -> SQL.RepeatableRead
-  "serializable"    -> SQL.Serializable
-  _                 -> SQL.ReadCommitted
-
-prefix :: Text
-prefix = "pgrst."
-
-- | In-db settings names
-dbSettingsNames :: [Text]
-dbSettingsNames =
-  (prefix <>) <$>
-  ["db_anon_role"
-  ,"db_pre_config"
-  ,"db_extra_search_path"
-  ,"db_max_rows"
-  ,"db_plan_enabled"
-  ,"db_pre_request"
-  ,"db_prepared_statements"
-  ,"db_root_spec"
-  ,"db_schemas"
-  ,"db_tx_end"
-  ,"db_use_legacy_gucs"
-  ,"jwt_aud"
-  ,"jwt_role_claim_key"
-  ,"jwt_secret"
-  ,"jwt_secret_is_base64"
-  ,"openapi_mode"
-  ,"openapi_security_active"
-  ,"openapi_server_proxy_uri"
-  ,"raw_media_types"
-  ,"server_trace_header"
-  ]
-
-queryPgVersion :: Bool -> Session PgVersion
-queryPgVersion prepared = statement mempty $ pgVersionStatement prepared
-
-pgVersionStatement :: Bool -> SQL.Statement () PgVersion
-pgVersionStatement = SQL.Statement sql HE.noParams versionRow
+pgVersionStatement :: SQL.Statement () PgVersion
+pgVersionStatement = SQL.Statement sql HE.noParams versionRow False
  where
    sql = "SELECT current_setting('server_version_num')::integer, current_setting('server_version')"
    versionRow = HD.singleRow $ PgVersion <$> column HD.int4 <*> column HD.text

-- | Query the in-database configuration. The settings have the following priorities:
--
-- 1. Role + with database-specific settings:
--    ALTER ROLE authenticator IN DATABASE postgres SET <prefix>jwt_aud = 'val';
-- 2. Role + with settings:
--    ALTER ROLE authenticator SET <prefix>jwt_aud = 'overridden';
-- 3. pre-config function:
--    CREATE FUNCTION pre_config() .. PERFORM set_config(<prefix>jwt_aud, 'pre_config_aud'..)
--
-- The example above will result in <prefix>jwt_aud = 'val'
-- A setting on the database only will have no effect: ALTER DATABASE postgres SET <prefix>jwt_aud = 'xx'
-queryDbSettings :: Maybe Text -> Bool -> Session [(Text, Text)]
-queryDbSettings preConfFunc prepared =
+queryDbSettings :: SQL.Pool -> Bool -> IO (Either SQL.UsageError [(Text, Text)])
+queryDbSettings pool prepared =
  let transaction = if prepared then SQL.transaction else SQL.unpreparedTransaction in
-  transaction SQL.ReadCommitted SQL.Read $ SQL.statement dbSettingsNames $ SQL.Statement sql (arrayParam HE.text) decodeSettings prepared
-  where
-    sql = [qc|
-      WITH
-      role_setting AS (
-        SELECT setdatabase as database,
-               unnest(setconfig) as setting
-        FROM pg_catalog.pg_db_role_setting
-        WHERE setrole = CURRENT_USER::regrole::oid
-          AND setdatabase IN (0, (SELECT oid FROM pg_catalog.pg_database WHERE datname = CURRENT_CATALOG))
-      ),
-      kv_settings AS (
-        SELECT database,
-               substr(setting, 1, strpos(setting, '=') - 1) as k,
-               substr(setting, strpos(setting, '=') + 1) as v
-        FROM role_setting
-        {preConfigF}
-      )
-      SELECT DISTINCT ON (key)
-             replace(k, '{prefix}', '') AS key,
-             v AS value
-      FROM kv_settings
-      WHERE k = ANY($1) AND v IS NOT NULL
-      ORDER BY key, database DESC NULLS LAST;
-    |]
-    preConfigF = case preConfFunc of
-      Nothing   -> mempty
-      Just func -> [qc|
-          UNION
-          SELECT
-            null as database,
-            x as k,
-            current_setting(x, true) as v
-          FROM unnest($1) x
-          JOIN {func}() _ ON TRUE
-      |]::Text
-    decodeSettings = HD.rowList $ (,) <$> column HD.text <*> column HD.text
+  SQL.use pool . transaction SQL.ReadCommitted SQL.Read $
+    SQL.statement mempty dbSettingsStatement

-queryRoleSettings :: Bool -> Session (RoleSettings, RoleIsolationLvl)
-queryRoleSettings prepared =
-  let transaction = if prepared then SQL.transaction else SQL.unpreparedTransaction in
-  transaction SQL.ReadCommitted SQL.Read $ SQL.statement mempty $ SQL.Statement sql HE.noParams (processRows <$> rows) prepared
+-- | Get db settings from the connection role. Global settings will be overridden by database specific settings.
+dbSettingsStatement :: SQL.Statement () [(Text, Text)]
+dbSettingsStatement = SQL.Statement sql HE.noParams decodeSettings False
  where
    sql = [q|
-      with
-      role_setting as (
-        select r.rolname, unnest(r.rolconfig) as setting
-        from pg_auth_members m
-        join pg_roles r on r.oid = m.roleid
-        where member = current_user::regrole::oid
+      WITH
+      role_setting (database, setting) AS (
+        SELECT setdatabase,
+               unnest(setconfig)
+          FROM pg_catalog.pg_db_role_setting
+         WHERE setrole = CURRENT_USER::regrole::oid
+           AND setdatabase IN (0, (SELECT oid FROM pg_catalog.pg_database WHERE datname = CURRENT_CATALOG))
      ),
-      kv_settings AS (
-        SELECT
-          rolname,
-          substr(setting, 1, strpos(setting, '=') - 1) as key,
-          lower(substr(setting, strpos(setting, '=') + 1)) as value
-        FROM role_setting
-      ),
-      iso_setting AS (
-        SELECT rolname, value
+      kv_settings (database, k, v) AS (
+        SELECT database,
+               substr(setting, 1, strpos(setting, '=') - 1),
+               substr(setting, strpos(setting, '=') + 1)
+          FROM role_setting
+         WHERE setting LIKE 'pgrst.%'
+      )
+      SELECT DISTINCT ON (key)
+             replace(k, 'pgrst.', '') AS key,
+             v AS value
        FROM kv_settings
-        WHERE key = 'default_transaction_isolation'
-      )
-      select
-        kv.rolname,
-        i.value as iso_lvl,
-        coalesce(array_agg(row(kv.key, kv.value)) filter (where key <> 'default_transaction_isolation'), '{}') as role_settings
-      from kv_settings kv
-      join pg_settings ps on ps.name = kv.key and ps.context = 'user'
-      left join iso_setting i on i.rolname = kv.rolname
-      group by kv.rolname, i.value;
+       ORDER BY key, database DESC;
    |]
-
-    processRows :: [(Text, Maybe Text, [(Text, Text)])] -> (RoleSettings, RoleIsolationLvl)
-    processRows rs =
-      let
-        rowsWRoleSettings = [ (x, z) | (x, _, z) <- rs ]
-        rowsWIsolation    = [ (x, y) | (x, Just y, _) <- rs ]
-      in
-      ( HM.fromList $ bimap encodeUtf8 (HM.fromList . ((encodeUtf8 *** encodeUtf8) <$>)) <$> rowsWRoleSettings
-      , HM.fromList $ (encodeUtf8 *** toIsolationLevel) <$> rowsWIsolation
-      )
-
-    rows :: HD.Result [(Text, Maybe Text, [(Text, Text)])]
-    rows = HD.rowList $ (,,) <$> column HD.text <*> nullableColumn HD.text <*> compositeArrayColumn ((,) <$> compositeField HD.text <*> compositeField HD.text)
+    decodeSettings = HD.rowList $ (,) <$> column HD.text <*> column HD.text

 column :: HD.Value a -> HD.Row a
 column = HD.column . HD.nonNullable
-
-nullableColumn :: HD.Value a -> HD.Row (Maybe a)
-nullableColumn = HD.column . HD.nullable
-
-compositeField :: HD.Value a -> HD.Composite a
-compositeField = HD.field . HD.nonNullable
-
-compositeArrayColumn :: HD.Composite a -> HD.Row [a]
-compositeArrayColumn = arrayColumn . HD.composite
-
-arrayColumn :: HD.Value a -> HD.Row [a]
-arrayColumn = column . HD.listArray . HD.nonNullable
-
-param :: HE.Value a -> HE.Params a
-param = HE.param . HE.nonNullable
-
-arrayParam :: HE.Value a -> HE.Params [a]
-arrayParam = param . HE.foldableArray . HE.nonNullable
@@ -9,7 +9,6 @@ module PostgREST.Config.PgVersion
  , pgVersion110
  , pgVersion112
  , pgVersion114
-  , pgVersion120
  , pgVersion121
  , pgVersion130
  , pgVersion140
@@ -51,9 +50,6 @@ pgVersion112 = PgVersion 110002 "11.2"
 pgVersion114 :: PgVersion
 pgVersion114 = PgVersion 110004 "11.4"

-pgVersion120 :: PgVersion
-pgVersion120 = PgVersion 120000 "12.0"
-
 pgVersion121 :: PgVersion
 pgVersion121 = PgVersion 120001 "12.1"

@@ -0,0 +1,64 @@
+{-# LANGUAGE DuplicateRecordFields #-}
+
+module PostgREST.ContentType
+  ( ContentType(..)
+  , toHeader
+  , toMime
+  , decodeContentType
+  ) where
+
+import qualified Data.ByteString          as BS
+import qualified Data.ByteString.Internal as BS (c2w)
+
+import Network.HTTP.Types.Header (Header, hContentType)
+
+import Protolude
+
+-- | Enumeration of currently supported response content types
+data ContentType
+  = CTApplicationJSON
+  | CTSingularJSON
+  | CTTextCSV
+  | CTTextPlain
+  | CTOpenAPI
+  | CTUrlEncoded
+  | CTOctetStream
+  | CTAny
+  | CTOther ByteString
+  deriving (Eq)
+
+-- | Convert from ContentType to a full HTTP Header
+toHeader :: ContentType -> Header
+toHeader ct = (hContentType, toMime ct <> charset)
+  where
+    charset = case ct of
+      CTOctetStream -> mempty
+      CTOther _     -> mempty
+      _             -> "; charset=utf-8"
+
+-- | Convert from ContentType to a ByteString representing the mime type
+toMime :: ContentType -> ByteString
+toMime CTApplicationJSON = "application/json"
+toMime CTTextCSV         = "text/csv"
+toMime CTTextPlain       = "text/plain"
+toMime CTOpenAPI         = "application/openapi+json"
+toMime CTSingularJSON    = "application/vnd.pgrst.object+json"
+toMime CTUrlEncoded      = "application/x-www-form-urlencoded"
+toMime CTOctetStream     = "application/octet-stream"
+toMime CTAny             = "*/*"
+toMime (CTOther ct)      = ct
+
+-- | Convert from ByteString to ContentType. Warning: discards MIME parameters
+decodeContentType :: BS.ByteString -> ContentType
+decodeContentType ct =
+  case BS.takeWhile (/= BS.c2w ';') ct of
+    "application/json"                  -> CTApplicationJSON
+    "text/csv"                          -> CTTextCSV
+    "text/plain"                        -> CTTextPlain
+    "application/openapi+json"          -> CTOpenAPI
+    "application/vnd.pgrst.object+json" -> CTSingularJSON
+    "application/vnd.pgrst.object"      -> CTSingularJSON
+    "application/x-www-form-urlencoded" -> CTUrlEncoded
+    "application/octet-stream"          -> CTOctetStream
+    "*/*"                               -> CTAny
+    ct'                                 -> CTOther ct'
@@ -0,0 +1,930 @@
+{-|
+Module      : PostgREST.DbStructure
+Description : PostgREST schema cache
+
+This module contains queries that target PostgreSQL system catalogs, these are used to build the schema cache(DbStructure).
+
+The schema cache is necessary for resource embedding, foreign keys are used for inferring the relationships between tables.
+
+These queries are executed once at startup or when PostgREST is reloaded.
+-}
+{-# LANGUAGE DeriveAnyClass        #-}
+{-# LANGUAGE DeriveGeneric         #-}
+{-# LANGUAGE FlexibleContexts      #-}
+{-# LANGUAGE MultiParamTypeClasses #-}
+{-# LANGUAGE NamedFieldPuns        #-}
+{-# LANGUAGE QuasiQuotes           #-}
+{-# LANGUAGE RecordWildCards       #-}
+{-# LANGUAGE ScopedTypeVariables   #-}
+{-# LANGUAGE TypeSynonymInstances  #-}
+
+module PostgREST.DbStructure
+  ( DbStructure(..)
+  , queryDbStructure
+  , accessibleTables
+  , accessibleProcs
+  , schemaDescription
+  , tableCols
+  , tablePKCols
+  ) where
+
+import qualified Data.Aeson          as JSON
+import qualified Data.HashMap.Strict as M
+import qualified Data.List           as L
+import qualified Hasql.Decoders      as HD
+import qualified Hasql.Encoders      as HE
+import qualified Hasql.Statement     as SQL
+import qualified Hasql.Transaction   as SQL
+
+import Contravariant.Extras          (contrazip2)
+import Data.Set                      as S (fromList)
+import Data.Text                     (split)
+import Text.InterpolatedString.Perl6 (q)
+
+import PostgREST.Config.Database          (pgVersionStatement)
+import PostgREST.Config.PgVersion         (PgVersion, pgVersion100,
+                                           pgVersion110)
+import PostgREST.DbStructure.Identifiers  (QualifiedIdentifier (..),
+                                           Schema, TableName)
+import PostgREST.DbStructure.Proc         (PgType (..),
+                                           ProcDescription (..),
+                                           ProcParam (..),
+                                           ProcVolatility (..),
+                                           ProcsMap, RetType (..))
+import PostgREST.DbStructure.Relationship (Cardinality (..),
+                                           Junction (..),
+                                           PrimaryKey (..),
+                                           Relationship (..))
+import PostgREST.DbStructure.Table        (Column (..), Table (..))
+
+import Protolude
+import Protolude.Unsafe (unsafeHead)
+
+
+data DbStructure = DbStructure
+  { dbTables        :: [Table]
+  , dbColumns       :: [Column]
+  , dbRelationships :: [Relationship]
+  , dbPrimaryKeys   :: [PrimaryKey]
+  , dbProcs         :: ProcsMap
+  }
+  deriving (Generic, JSON.ToJSON)
+
+-- TODO Table could hold references to all its Columns
+tableCols :: DbStructure -> Schema -> TableName -> [Column]
+tableCols dbs tSchema tName = filter (\Column{colTable=Table{tableSchema=s, tableName=t}} -> s==tSchema && t==tName) $ dbColumns dbs
+
+-- TODO Table could hold references to all its PrimaryKeys
+tablePKCols :: DbStructure -> Schema -> TableName -> [Text]
+tablePKCols dbs tSchema tName =  pkName <$> filter (\pk -> tSchema == (tableSchema . pkTable) pk && tName == (tableName . pkTable) pk) (dbPrimaryKeys dbs)
+
+-- | The source table column a view column refers to
+type SourceColumn = (Column, ViewColumn)
+type ViewColumn = Column
+
+-- | A SQL query that can be executed independently
+type SqlQuery = ByteString
+
+queryDbStructure :: [Schema] -> [Schema] -> Bool -> SQL.Transaction DbStructure
+queryDbStructure schemas extraSearchPath prepared = do
+  SQL.sql "set local schema ''" -- This voids the search path. The following queries need this for getting the fully qualified name(schema.name) of every db object
+  pgVer   <- SQL.statement mempty pgVersionStatement
+  tabs    <- SQL.statement mempty $ allTables pgVer prepared
+  cols    <- SQL.statement schemas $ allColumns tabs prepared
+  srcCols <- SQL.statement (schemas, extraSearchPath) $ pfkSourceColumns cols prepared
+  m2oRels <- SQL.statement mempty $ allM2ORels tabs cols prepared
+  keys    <- SQL.statement mempty $ allPrimaryKeys tabs prepared
+  procs   <- SQL.statement schemas $ allProcs pgVer prepared
+
+  let rels = addO2MRels . addM2MRels $ addViewM2ORels srcCols m2oRels
+      keys' = addViewPrimaryKeys srcCols keys
+
+  return $ removeInternal schemas $ DbStructure {
+      dbTables = tabs
+    , dbColumns = cols
+    , dbRelationships = rels
+    , dbPrimaryKeys = keys'
+    , dbProcs = procs
+    }
+
+-- | Remove db objects that belong to an internal schema(not exposed through the API) from the DbStructure.
+removeInternal :: [Schema] -> DbStructure -> DbStructure
+removeInternal schemas dbStruct =
+  DbStructure {
+      dbTables        = filter (\x -> tableSchema x `elem` schemas) $ dbTables dbStruct
+    , dbColumns       = filter (\x -> tableSchema (colTable x) `elem` schemas) (dbColumns dbStruct)
+    , dbRelationships = filter (\x -> tableSchema (relTable x) `elem` schemas &&
+                                      tableSchema (relForeignTable x) `elem` schemas &&
+                                      not (hasInternalJunction x)) $ dbRelationships dbStruct
+    , dbPrimaryKeys   = filter (\x -> tableSchema (pkTable x) `elem` schemas) $ dbPrimaryKeys dbStruct
+    , dbProcs         = dbProcs dbStruct -- procs are only obtained from the exposed schemas, no need to filter them.
+    }
+  where
+    hasInternalJunction rel = case relCardinality rel of
+      M2M Junction{junTable} -> tableSchema junTable `notElem` schemas
+      _                      -> False
+
+decodeTables :: HD.Result [Table]
+decodeTables =
+  HD.rowList tblRow
+ where
+  tblRow = Table <$> column HD.text
+                 <*> column HD.text
+                 <*> nullableColumn HD.text
+                 <*> column HD.bool
+                 <*> column HD.bool
+                 <*> column HD.bool
+
+decodeColumns :: [Table] -> HD.Result [Column]
+decodeColumns tables =
+  mapMaybe (columnFromRow tables) <$> HD.rowList colRow
+ where
+  colRow =
+    (,,,,,,,,)
+      <$> column HD.text
+      <*> column HD.text
+      <*> column HD.text
+      <*> nullableColumn HD.text
+      <*> column HD.bool
+      <*> column HD.text
+      <*> nullableColumn HD.int4
+      <*> nullableColumn HD.text
+      <*> nullableColumn HD.text
+
+decodeRels :: [Table] -> [Column] -> HD.Result [Relationship]
+decodeRels tables cols =
+  mapMaybe (relFromRow tables cols) <$> HD.rowList relRow
+ where
+  relRow = (,,,,,,)
+    <$> column HD.text
+    <*> column HD.text
+    <*> column HD.text
+    <*> arrayColumn HD.text
+    <*> column HD.text
+    <*> column HD.text
+    <*> arrayColumn HD.text
+
+decodePks :: [Table] -> HD.Result [PrimaryKey]
+decodePks tables =
+  mapMaybe (pkFromRow tables) <$> HD.rowList pkRow
+ where
+  pkRow = (,,) <$> column HD.text <*> column HD.text <*> column HD.text
+
+decodeSourceColumns :: [Column] -> HD.Result [SourceColumn]
+decodeSourceColumns cols =
+  mapMaybe (sourceColumnFromRow cols) <$> HD.rowList srcColRow
+ where
+  srcColRow = (,,,,,)
+    <$> column HD.text <*> column HD.text
+    <*> column HD.text <*> column HD.text
+    <*> column HD.text <*> column HD.text
+
+sourceColumnFromRow :: [Column] -> (Text,Text,Text,Text,Text,Text) -> Maybe SourceColumn
+sourceColumnFromRow allCols (s1,t1,c1,s2,t2,c2) = (,) <$> col1 <*> col2
+  where
+    col1 = findCol s1 t1 c1
+    col2 = findCol s2 t2 c2
+    findCol s t c = find (\col -> (tableSchema . colTable) col == s && (tableName . colTable) col == t && colName col == c) allCols
+
+decodeProcs :: HD.Result ProcsMap
+decodeProcs =
+  -- Duplicate rows for a function means they're overloaded, order these by least args according to ProcDescription Ord instance
+  map sort . M.fromListWith (++) . map ((\(x,y) -> (x, [y])) . addKey) <$> HD.rowList procRow
+  where
+    procRow = ProcDescription
+              <$> column HD.text
+              <*> column HD.text
+              <*> nullableColumn HD.text
+              <*> compositeArrayColumn
+                  (ProcParam
+                  <$> compositeField HD.text
+                  <*> compositeField HD.text
+                  <*> compositeField HD.bool
+                  <*> compositeField HD.bool)
+              <*> (parseRetType
+                  <$> column HD.text
+                  <*> column HD.text
+                  <*> column HD.bool
+                  <*> column HD.bool)
+              <*> (parseVolatility <$> column HD.char)
+              <*> column HD.bool
+
+    addKey :: ProcDescription -> (QualifiedIdentifier, ProcDescription)
+    addKey pd = (QualifiedIdentifier (pdSchema pd) (pdName pd), pd)
+
+    parseRetType :: Text -> Text -> Bool -> Bool -> RetType
+    parseRetType schema name isSetOf isComposite
+      | isSetOf   = SetOf pgType
+      | otherwise = Single pgType
+      where
+        qi = QualifiedIdentifier schema name
+        pgType
+          | isComposite = Composite qi
+          | otherwise   = Scalar
+
+    parseVolatility :: Char -> ProcVolatility
+    parseVolatility v | v == 'i' = Immutable
+                      | v == 's' = Stable
+                      | otherwise = Volatile -- only 'v' can happen here
+
+allProcs :: PgVersion -> Bool -> SQL.Statement [Schema] ProcsMap
+allProcs pgVer = SQL.Statement sql (arrayParam HE.text) decodeProcs
+  where
+    sql = procsSqlQuery pgVer <> " AND pn.nspname = ANY($1)"
+
+accessibleProcs :: PgVersion -> Bool -> SQL.Statement Schema ProcsMap
+accessibleProcs pgVer = SQL.Statement sql (param HE.text) decodeProcs
+  where
+    sql = procsSqlQuery pgVer <> " AND pn.nspname = $1 AND has_function_privilege(p.oid, 'execute')"
+
+procsSqlQuery :: PgVersion -> SqlQuery
+procsSqlQuery pgVer = [q|
+ -- Recursively get the base types of domains
+  WITH
+  base_types AS (
+    WITH RECURSIVE
+    recurse AS (
+      SELECT
+        oid,
+        typbasetype,
+        COALESCE(NULLIF(typbasetype, 0), oid) AS base
+      FROM pg_type
+      UNION
+      SELECT
+        t.oid,
+        b.typbasetype,
+        COALESCE(NULLIF(b.typbasetype, 0), b.oid) AS base
+      FROM recurse t
+      JOIN pg_type b ON t.typbasetype = b.oid
+    )
+    SELECT
+      oid,
+      base
+    FROM recurse
+    WHERE typbasetype = 0
+  ),
+  arguments AS (
+    SELECT
+      oid,
+      array_agg((
+        COALESCE(name, ''), -- name
+        type::regtype::text, -- type
+        idx <= (pronargs - pronargdefaults), -- is_required
+        COALESCE(mode = 'v', FALSE) -- is_variadic
+      ) ORDER BY idx) AS args
+    FROM pg_proc,
+         unnest(proargnames, proargtypes, proargmodes)
+           WITH ORDINALITY AS _ (name, type, mode, idx)
+    WHERE type IS NOT NULL -- only input arguments
+    GROUP BY oid
+  )
+  SELECT
+    pn.nspname AS proc_schema,
+    p.proname AS proc_name,
+    d.description AS proc_description,
+    COALESCE(a.args, '{}') AS args,
+    tn.nspname AS schema,
+    COALESCE(comp.relname, t.typname) AS name,
+    p.proretset AS rettype_is_setof,
+    (t.typtype = 'c'
+     -- if any TABLE, INOUT or OUT arguments present, treat as composite
+     or COALESCE(proargmodes::text[] && '{t,b,o}', false)
+    ) AS rettype_is_composite,
+    p.provolatile,
+    p.provariadic > 0 as hasvariadic
+  FROM pg_proc p
+  LEFT JOIN arguments a ON a.oid = p.oid
+  JOIN pg_namespace pn ON pn.oid = p.pronamespace
+  JOIN base_types bt ON bt.oid = p.prorettype
+  JOIN pg_type t ON t.oid = bt.base
+  JOIN pg_namespace tn ON tn.oid = t.typnamespace
+  LEFT JOIN pg_class comp ON comp.oid = t.typrelid
+  LEFT JOIN pg_catalog.pg_description as d ON d.objoid = p.oid
+  WHERE t.oid <> 'pg_catalog.trigger'::regtype
+|] <> (if pgVer >= pgVersion110 then "AND prokind = 'f'" else "AND NOT (proisagg OR proiswindow)")
+
+schemaDescription :: Bool -> SQL.Statement Schema (Maybe Text)
+schemaDescription =
+    SQL.Statement sql (param HE.text) (join <$> HD.rowMaybe (nullableColumn HD.text))
+  where
+    sql = [q|
+      select
+        description
+      from
+        pg_catalog.pg_namespace n
+        left join pg_catalog.pg_description d on d.objoid = n.oid
+      where
+        n.nspname = $1 |]
+
+accessibleTables :: PgVersion -> Bool -> SQL.Statement Schema [Table]
+accessibleTables pgVer =
+  SQL.Statement sql (param HE.text) decodeTables
+ where
+  sql = [q|
+    select
+      n.nspname as table_schema,
+      relname as table_name,
+      d.description as table_description,
+      (
+        c.relkind IN ('r','p')
+        OR (
+          c.relkind IN ('v','f')
+          -- CMD_INSERT - see allTables query below for explanation
+          AND (pg_relation_is_updatable(c.oid::regclass, TRUE) & 8) = 8
+        )
+      ) AS insertable,
+      (
+        c.relkind IN ('r','p')
+        OR (
+          c.relkind IN ('v','f')
+          -- CMD_UPDATE
+          AND (pg_relation_is_updatable(c.oid::regclass, TRUE) & 4) = 4
+        )
+      ) as updatable,
+      (
+        c.relkind IN ('r','p')
+        OR (
+          c.relkind IN ('v','f')
+          -- CMD_DELETE
+          AND (pg_relation_is_updatable(c.oid::regclass, TRUE) & 16) = 16
+        )
+      ) as deletable
+    from
+      pg_class c
+      join pg_namespace n on n.oid = c.relnamespace
+      left join pg_catalog.pg_description as d on d.objoid = c.oid and d.objsubid = 0
+    where
+      c.relkind in ('v','r','m','f','p')
+      and n.nspname = $1 |]
+      <> relIsNotPartition pgVer <> [q|
+      and (
+        pg_has_role(c.relowner, 'USAGE')
+        or has_table_privilege(c.oid, 'SELECT, INSERT, UPDATE, DELETE, TRUNCATE, REFERENCES, TRIGGER')
+        or has_any_column_privilege(c.oid, 'SELECT, INSERT, UPDATE, REFERENCES')
+      )
+    order by relname |]
+
+{-
+Adds Views M2O Relationships based on SourceColumns found, the logic is as follows:
+
+Having a Relationship{relTable=t1, relColumns=[c1], relFTable=t2, relFColumns=[c2], relCardinality=M2O} represented by:
+
+t1.c1------t2.c2
+
+When only having a t1_view.c1 source column, we need to add a View-Table M2O Relationship
+
+         t1.c1----t2.c2         t1.c1----------t2.c2
+                         ->            ________/
+                                      /
+      t1_view.c1             t1_view.c1
+
+
+When only having a t2_view.c2 source column, we need to add a Table-View M2O Relationship
+
+         t1.c1----t2.c2               t1.c1----------t2.c2
+                               ->          \________
+                                                    \
+                    t2_view.c2                      t2_view.c1
+
+When having t1_view.c1 and a t2_view.c2 source columns, we need to add a View-View M2O Relationship in addition to the prior
+
+         t1.c1----t2.c2               t1.c1----------t2.c2
+                               ->          \________/
+                                           /        \
+    t1_view.c1     t2_view.c2     t1_view.c1-------t2_view.c1
+
+The logic for composite pks is similar just need to make sure all the Relationship columns have source columns.
+-}
+addViewM2ORels :: [SourceColumn] -> [Relationship] -> [Relationship]
+addViewM2ORels allSrcCols = concatMap (\rel@Relationship{..} -> rel :
+  let
+    srcColsGroupedByView :: [Column] -> [[SourceColumn]]
+    srcColsGroupedByView relCols = L.groupBy (\(_, viewCol1) (_, viewCol2) -> colTable viewCol1 == colTable viewCol2) $
+                   filter (\(c, _) -> c `elem` relCols) allSrcCols
+    relSrcCols = srcColsGroupedByView relColumns
+    relFSrcCols = srcColsGroupedByView relForeignColumns
+    getView :: [SourceColumn] -> Table
+    getView = colTable . snd . unsafeHead
+    srcCols `allSrcColsOf` cols = S.fromList (fst <$> srcCols) == S.fromList cols
+    -- Relationship is dependent on the order of relColumns and relFColumns to get the join conditions right in the generated query.
+    -- So we need to change the order of the SourceColumns to match the relColumns
+    -- TODO: This could be avoided if the Relationship type is improved with a structure that maintains the association of relColumns and relFColumns
+    srcCols `sortAccordingTo` cols = sortOn (\(k, _) -> L.lookup k $ zip cols [0::Int ..]) srcCols
+
+    viewTableM2O =
+      [ Relationship
+          (getView srcCols) (snd <$> srcCols `sortAccordingTo` relColumns)
+          relForeignTable relForeignColumns relCardinality
+      | srcCols <- relSrcCols, srcCols `allSrcColsOf` relColumns ]
+
+    tableViewM2O =
+      [ Relationship
+          relTable relColumns
+          (getView fSrcCols) (snd <$> fSrcCols `sortAccordingTo` relForeignColumns)
+          relCardinality
+      | fSrcCols <- relFSrcCols, fSrcCols `allSrcColsOf` relForeignColumns ]
+
+    viewViewM2O =
+      [ Relationship
+          (getView srcCols) (snd <$> srcCols `sortAccordingTo` relColumns)
+          (getView fSrcCols) (snd <$> fSrcCols `sortAccordingTo` relForeignColumns)
+          relCardinality
+      | srcCols  <- relSrcCols, srcCols `allSrcColsOf` relColumns
+      , fSrcCols <- relFSrcCols, fSrcCols `allSrcColsOf` relForeignColumns ]
+
+  in viewTableM2O ++ tableViewM2O ++ viewViewM2O)
+
+addO2MRels :: [Relationship] -> [Relationship]
+addO2MRels rels = rels ++ [ Relationship ft fc t c (O2M cons)
+                          | Relationship t c ft fc (M2O cons) <- rels ]
+
+addM2MRels :: [Relationship] -> [Relationship]
+addM2MRels rels = rels ++ [ Relationship t c ft fc (M2M $ Junction jt1 cons1 jc1 cons2 jc2)
+                          | Relationship jt1 jc1 t c (M2O cons1) <- rels
+                          , Relationship jt2 jc2 ft fc (M2O cons2) <- rels
+                          , jt1 == jt2
+                          , cons1 /= cons2]
+
+addViewPrimaryKeys :: [SourceColumn] -> [PrimaryKey] -> [PrimaryKey]
+addViewPrimaryKeys srcCols = concatMap (\pk ->
+  let viewPks = (\(_, viewCol) -> PrimaryKey{pkTable=colTable viewCol, pkName=colName viewCol}) <$>
+                filter (\(col, _) -> colTable col == pkTable pk && colName col == pkName pk) srcCols in
+  pk : viewPks)
+
+allTables :: PgVersion -> Bool -> SQL.Statement () [Table]
+allTables pgVer =
+  SQL.Statement sql HE.noParams decodeTables
+ where
+  sql = [q|
+    SELECT
+      n.nspname AS table_schema,
+      c.relname AS table_name,
+      d.description AS table_description,
+      (
+        c.relkind IN ('r','p')
+        OR (
+          c.relkind in ('v','f')
+          -- The function `pg_relation_is_updateable` returns a bitmask where 8
+          -- corresponds to `1 << CMD_INSERT` in the PostgreSQL source code, i.e.
+          -- it's possible to insert into the relation.
+          AND (pg_relation_is_updatable(c.oid::regclass, TRUE) & 8) = 8
+        )
+      ) AS insertable,
+      (
+        c.relkind IN ('r','p')
+        OR (
+          c.relkind in ('v','f')
+          -- CMD_UPDATE
+          AND (pg_relation_is_updatable(c.oid::regclass, TRUE) & 4) = 4
+        )
+      ) AS updatable,
+      (
+        c.relkind IN ('r','p')
+        OR (
+          c.relkind in ('v','f')
+          -- CMD_DELETE
+          AND (pg_relation_is_updatable(c.oid::regclass, TRUE) & 16) = 16
+        )
+      ) AS deletable
+    FROM pg_class c
+    JOIN pg_namespace n ON n.oid = c.relnamespace
+    LEFT JOIN pg_catalog.pg_description as d on d.objoid = c.oid and d.objsubid = 0
+    WHERE c.relkind IN ('v','r','m','f','p')
+      AND n.nspname NOT IN ('pg_catalog', 'information_schema') |]
+      <> relIsNotPartition pgVer <> [q|
+    ORDER BY table_schema, table_name |]
+
+relIsNotPartition :: PgVersion -> SqlQuery
+relIsNotPartition pgVer = if pgVer >= pgVersion100 then " AND not c.relispartition " else mempty
+
+allColumns :: [Table] -> Bool -> SQL.Statement [Schema] [Column]
+allColumns tabs =
+ SQL.Statement sql (arrayParam HE.text) (decodeColumns tabs)
+ where
+  sql = [q|
+    SELECT DISTINCT
+        info.table_schema AS schema,
+        info.table_name AS table_name,
+        info.column_name AS name,
+        info.description AS description,
+        info.is_nullable::boolean AS nullable,
+        info.data_type AS col_type,
+        info.character_maximum_length AS max_len,
+        info.column_default AS default_value,
+        array_to_string(enum_info.vals, ',') AS enum,
+        info.position
+    FROM (
+        -- CTE based on pg_catalog to get PRIMARY/FOREIGN key and UNIQUE columns outside api schema
+        WITH key_columns AS (
+             SELECT
+               r.oid AS r_oid,
+               c.oid AS c_oid,
+               n.nspname,
+               c.relname,
+               r.conname,
+               r.contype,
+               unnest(r.conkey) AS conkey
+             FROM
+               pg_catalog.pg_constraint r,
+               pg_catalog.pg_class c,
+               pg_catalog.pg_namespace n
+             WHERE
+               r.contype IN ('f', 'p', 'u')
+               AND c.relkind IN ('r', 'v', 'f', 'm', 'p')
+               AND r.conrelid = c.oid
+               AND c.relnamespace = n.oid
+               AND n.nspname <> ANY (ARRAY['pg_catalog', 'information_schema'] || $1)
+        ),
+        /*
+        -- CTE based on information_schema.columns
+        -- changed:
+        -- remove the owner filter
+        -- limit columns to the ones in the api schema or PK/FK columns
+        */
+        columns AS (
+            SELECT
+                nc.nspname::name AS table_schema,
+                c.relname::name AS table_name,
+                a.attname::name AS column_name,
+                d.description AS description,
+                pg_get_expr(ad.adbin, ad.adrelid)::text AS column_default,
+                not (a.attnotnull OR t.typtype = 'd' AND t.typnotnull) AS is_nullable,
+                    CASE
+                        WHEN t.typtype = 'd' THEN
+                        CASE
+                            WHEN bt.typelem <> 0::oid AND bt.typlen = (-1) THEN 'ARRAY'::text
+                            WHEN nbt.nspname = 'pg_catalog'::name THEN format_type(t.typbasetype, NULL::integer)
+                            ELSE format_type(a.atttypid, a.atttypmod)
+                        END
+                        ELSE
+                        CASE
+                            WHEN t.typelem <> 0::oid AND t.typlen = (-1) THEN 'ARRAY'::text
+                            WHEN nt.nspname = 'pg_catalog'::name THEN format_type(a.atttypid, NULL::integer)
+                            ELSE format_type(a.atttypid, a.atttypmod)
+                        END
+                    END::text AS data_type,
+                information_schema._pg_char_max_length(
+                    information_schema._pg_truetypid(a.*, t.*),
+                    information_schema._pg_truetypmod(a.*, t.*)
+                )::integer AS character_maximum_length,
+                COALESCE(bt.typname, t.typname)::name AS udt_name,
+                a.attnum::integer AS position
+            FROM pg_attribute a
+                LEFT JOIN key_columns kc
+                    ON kc.conkey = a.attnum AND kc.c_oid = a.attrelid
+                LEFT JOIN pg_catalog.pg_description AS d
+                    ON d.objoid = a.attrelid and d.objsubid = a.attnum
+                LEFT JOIN pg_attrdef ad
+                    ON a.attrelid = ad.adrelid AND a.attnum = ad.adnum
+                JOIN (pg_class c JOIN pg_namespace nc ON c.relnamespace = nc.oid)
+                    ON a.attrelid = c.oid
+                JOIN (pg_type t JOIN pg_namespace nt ON t.typnamespace = nt.oid)
+                    ON a.atttypid = t.oid
+                LEFT JOIN (pg_type bt JOIN pg_namespace nbt ON bt.typnamespace = nbt.oid)
+                    ON t.typtype = 'd' AND t.typbasetype = bt.oid
+                LEFT JOIN (pg_collation co JOIN pg_namespace nco ON co.collnamespace = nco.oid)
+                    ON a.attcollation = co.oid AND (nco.nspname <> 'pg_catalog'::name OR co.collname <> 'default'::name)
+            WHERE
+                NOT pg_is_other_temp_schema(nc.oid)
+                AND a.attnum > 0
+                AND NOT a.attisdropped
+                AND c.relkind in ('r', 'v', 'f', 'm', 'p')
+                -- Filter only columns that are FK/PK or in the api schema:
+                AND (nc.nspname = ANY ($1) OR kc.r_oid IS NOT NULL)
+        )
+        SELECT
+            table_schema,
+            table_name,
+            column_name,
+            description,
+            is_nullable,
+            data_type,
+            character_maximum_length,
+            column_default,
+            udt_name,
+            position
+        FROM columns
+        WHERE table_schema NOT IN ('pg_catalog', 'information_schema')
+    ) AS info
+    LEFT OUTER JOIN (
+        SELECT
+            n.nspname AS s,
+            t.typname AS n,
+            array_agg(e.enumlabel ORDER BY e.enumsortorder) AS vals
+        FROM pg_type t
+        JOIN pg_enum e ON t.oid = e.enumtypid
+        JOIN pg_catalog.pg_namespace n ON n.oid = t.typnamespace
+        GROUP BY s,n
+    ) AS enum_info ON (info.udt_name = enum_info.n)
+    ORDER BY schema, position |]
+
+columnFromRow :: [Table] ->
+                 (Text,        Text,        Text,
+                  Maybe Text,  Bool,        Text,
+                  Maybe Int32, Maybe Text,  Maybe Text)
+                 -> Maybe Column
+columnFromRow tabs (s, t, n, desc, nul, typ, l, d, e) = buildColumn <$> table
+  where
+    buildColumn tbl = Column tbl n desc nul typ l d (parseEnum e)
+    table = find (\tbl -> tableSchema tbl == s && tableName tbl == t) tabs
+    parseEnum :: Maybe Text -> [Text]
+    parseEnum = maybe [] (split (==','))
+
+allM2ORels :: [Table] -> [Column] -> Bool -> SQL.Statement () [Relationship]
+allM2ORels tabs cols =
+  SQL.Statement sql HE.noParams (decodeRels tabs cols)
+ where
+  sql = [q|
+    SELECT ns1.nspname AS table_schema,
+           tab.relname AS table_name,
+           conname     AS constraint_name,
+           column_info.cols AS columns,
+           ns2.nspname AS foreign_table_schema,
+           other.relname AS foreign_table_name,
+           column_info.refs AS foreign_columns
+    FROM pg_constraint,
+    LATERAL (
+      SELECT array_agg(cols.attname) AS cols,
+                    array_agg(cols.attnum)  AS nums,
+                    array_agg(refs.attname) AS refs
+      FROM ( SELECT unnest(conkey) AS col, unnest(confkey) AS ref) k,
+      LATERAL (SELECT * FROM pg_attribute WHERE attrelid = conrelid AND attnum = col) AS cols,
+      LATERAL (SELECT * FROM pg_attribute WHERE attrelid = confrelid AND attnum = ref) AS refs) AS column_info,
+    LATERAL (SELECT * FROM pg_namespace WHERE pg_namespace.oid = connamespace) AS ns1,
+    LATERAL (SELECT * FROM pg_class WHERE pg_class.oid = conrelid) AS tab,
+    LATERAL (SELECT * FROM pg_class WHERE pg_class.oid = confrelid) AS other,
+    LATERAL (SELECT * FROM pg_namespace WHERE pg_namespace.oid = other.relnamespace) AS ns2
+    WHERE confrelid != 0
+    ORDER BY (conrelid, column_info.nums) |]
+
+relFromRow :: [Table] -> [Column] -> (Text, Text, Text, [Text], Text, Text, [Text]) -> Maybe Relationship
+relFromRow allTabs allCols (rs, rt, cn, rcs, frs, frt, frcs) =
+  Relationship <$> table <*> cols <*> tableF <*> colsF <*> pure (M2O cn)
+  where
+    findTable s t = find (\tbl -> tableSchema tbl == s && tableName tbl == t) allTabs
+    findCol s t c = find (\col -> tableSchema (colTable col) == s && tableName (colTable col) == t && colName col == c) allCols
+    table  = findTable rs rt
+    tableF = findTable frs frt
+    cols  = mapM (findCol rs rt) rcs
+    colsF = mapM (findCol frs frt) frcs
+
+allPrimaryKeys :: [Table] -> Bool -> SQL.Statement () [PrimaryKey]
+allPrimaryKeys tabs =
+  SQL.Statement sql HE.noParams (decodePks tabs)
+ where
+  sql = [q|
+    -- CTE to replace information_schema.table_constraints to remove owner limit
+    WITH tc AS (
+        SELECT
+            c.conname::name AS constraint_name,
+            nr.nspname::name AS table_schema,
+            r.relname::name AS table_name
+        FROM pg_namespace nc,
+            pg_namespace nr,
+            pg_constraint c,
+            pg_class r
+        WHERE
+            nc.oid = c.connamespace
+            AND nr.oid = r.relnamespace
+            AND c.conrelid = r.oid
+            AND r.relkind IN ('r', 'p')
+            AND NOT pg_is_other_temp_schema(nr.oid)
+            AND c.contype = 'p'
+    ),
+    -- CTE to replace information_schema.key_column_usage to remove owner limit
+    kc AS (
+        SELECT
+            ss.conname::name AS constraint_name,
+            ss.nr_nspname::name AS table_schema,
+            ss.relname::name AS table_name,
+            a.attname::name AS column_name,
+            (ss.x).n::integer AS ordinal_position,
+            CASE
+                WHEN ss.contype = 'f' THEN information_schema._pg_index_position(ss.conindid, ss.confkey[(ss.x).n])
+                ELSE NULL::integer
+            END::integer AS position_in_unique_constraint
+        FROM pg_attribute a,
+            ( SELECT r.oid AS roid,
+                r.relname,
+                r.relowner,
+                nc.nspname AS nc_nspname,
+                nr.nspname AS nr_nspname,
+                c.oid AS coid,
+                c.conname,
+                c.contype,
+                c.conindid,
+                c.confkey,
+                information_schema._pg_expandarray(c.conkey) AS x
+               FROM pg_namespace nr,
+                pg_class r,
+                pg_namespace nc,
+                pg_constraint c
+              WHERE
+                nr.oid = r.relnamespace
+                AND r.oid = c.conrelid
+                AND nc.oid = c.connamespace
+                AND c.contype in ('p', 'u', 'f')
+                AND r.relkind IN ('r', 'p')
+                AND NOT pg_is_other_temp_schema(nr.oid)
+            ) ss
+        WHERE
+          ss.roid = a.attrelid
+          AND a.attnum = (ss.x).x
+          AND NOT a.attisdropped
+    )
+    SELECT
+        kc.table_schema,
+        kc.table_name,
+        kc.column_name
+    FROM
+        tc, kc
+    WHERE
+        kc.table_name = tc.table_name AND
+        kc.table_schema = tc.table_schema AND
+        kc.constraint_name = tc.constraint_name AND
+        kc.table_schema NOT IN ('pg_catalog', 'information_schema') |]
+
+pkFromRow :: [Table] -> (Schema, Text, Text) -> Maybe PrimaryKey
+pkFromRow tabs (s, t, n) = PrimaryKey <$> table <*> pure n
+  where table = find (\tbl -> tableSchema tbl == s && tableName tbl == t) tabs
+
+-- returns all the primary and foreign key columns which are referenced in views
+pfkSourceColumns :: [Column] -> Bool -> SQL.Statement ([Schema], [Schema]) [SourceColumn]
+pfkSourceColumns cols =
+  SQL.Statement sql (contrazip2 (arrayParam HE.text) (arrayParam HE.text)) (decodeSourceColumns cols)
+  -- query explanation at:
+  --  * rationale: https://gist.github.com/wolfgangwalther/5425d64e7b0d20aad71f6f68474d9f19
+  --  * json transformation: https://gist.github.com/wolfgangwalther/3a8939da680c24ad767e93ad2c183089
+  where
+    sql = [q|
+      with recursive
+      pks_fks as (
+        -- pk + fk referencing col
+        select
+          conrelid as resorigtbl,
+          unnest(conkey) as resorigcol
+        from pg_constraint
+        where contype IN ('p', 'f')
+        union
+        -- fk referenced col
+        select
+          confrelid,
+          unnest(confkey)
+        from pg_constraint
+        where contype='f'
+      ),
+      views as (
+        select
+          c.oid       as view_id,
+          n.nspname   as view_schema,
+          c.relname   as view_name,
+          r.ev_action as view_definition
+        from pg_class c
+        join pg_namespace n on n.oid = c.relnamespace
+        join pg_rewrite r on r.ev_class = c.oid
+        where c.relkind in ('v', 'm') and n.nspname = ANY($1 || $2)
+      ),
+      transform_json as (
+        select
+          view_id, view_schema, view_name,
+          -- the following formatting is without indentation on purpose
+          -- to allow simple diffs, with less whitespace noise
+          replace(
+            replace(
+            replace(
+            replace(
+            replace(
+            replace(
+            replace(
+            regexp_replace(
+            replace(
+            replace(
+            replace(
+            replace(
+            replace(
+            replace(
+            replace(
+            replace(
+            replace(
+            replace(
+            replace(
+              view_definition::text,
+            -- This conversion to json is heavily optimized for performance.
+            -- The general idea is to use as few regexp_replace() calls as possible.
+            -- Simple replace() is a lot faster, so we jump through some hoops
+            -- to be able to use regexp_replace() only once.
+            -- This has been tested against a huge schema with 250+ different views.
+            -- The unit tests do NOT reflect all possible inputs. Be careful when changing this!
+            -- -----------------------------------------------
+            -- pattern           | replacement         | flags
+            -- -----------------------------------------------
+            -- `<>` in pg_node_tree is the same as `null` in JSON, but due to very poor performance of json_typeof
+            -- we need to make this an empty array here to prevent json_array_elements from throwing an error
+            -- when the targetList is null.
+            -- We'll need to put it first, to make the node protection below work for node lists that start with
+            -- null: `(<> ...`, too. This is the case for coldefexprs, when the first column does not have a default value.
+               '<>'              , '()'
+            -- `,` is not part of the pg_node_tree format, but used in the regex.
+            -- This removes all `,` that might be part of column names.
+            ), ','               , ''
+            -- The same applies for `{` and `}`, although those are used a lot in pg_node_tree.
+            -- We remove the escaped ones, which might be part of column names again.
+            ), E'\\{'            , ''
+            ), E'\\}'            , ''
+            -- The fields we need are formatted as json manually to protect them from the regex.
+            ), ' :targetList '   , ',"targetList":'
+            ), ' :resno '        , ',"resno":'
+            ), ' :resorigtbl '   , ',"resorigtbl":'
+            ), ' :resorigcol '   , ',"resorigcol":'
+            -- Make the regex also match the node type, e.g. `{QUERY ...`, to remove it in one pass.
+            ), '{'               , '{ :'
+            -- Protect node lists, which start with `({` or `((` from the greedy regex.
+            -- The extra `{` is removed again later.
+            ), '(('              , '{(('
+            ), '({'              , '{({'
+            -- This regex removes all unused fields to avoid the need to format all of them correctly.
+            -- This leads to a smaller json result as well.
+            -- Removal stops at `,` for used fields (see above) and `}` for the end of the current node.
+            -- Nesting can't be parsed correctly with a regex, so we stop at `{` as well and
+            -- add an empty key for the followig node.
+            ), ' :[^}{,]+'       , ',"":'              , 'g'
+            -- For performance, the regex also added those empty keys when hitting a `,` or `}`.
+            -- Those are removed next.
+            ), ',"":}'           , '}'
+            ), ',"":,'           , ','
+            -- This reverses the "node list protection" from above.
+            ), '{('              , '('
+            -- Every key above has been added with a `,` so far. The first key in an object doesn't need it.
+            ), '{,'              , '{'
+            -- pg_node_tree has `()` around lists, but JSON uses `[]`
+            ), '('               , '['
+            ), ')'               , ']'
+            -- pg_node_tree has ` ` between list items, but JSON uses `,`
+            ), ' '             , ','
+          )::json as view_definition
+        from views
+      ),
+      target_entries as(
+        select
+          view_id, view_schema, view_name,
+          json_array_elements(view_definition->0->'targetList') as entry
+        from transform_json
+      ),
+      results as(
+        select
+          view_id, view_schema, view_name,
+          (entry->>'resno')::int as view_column,
+          (entry->>'resorigtbl')::oid as resorigtbl,
+          (entry->>'resorigcol')::int as resorigcol
+        from target_entries
+      ),
+      recursion as(
+        select r.*
+        from results r
+        where view_schema = ANY ($1)
+        union all
+        select
+          view.view_id,
+          view.view_schema,
+          view.view_name,
+          view.view_column,
+          tab.resorigtbl,
+          tab.resorigcol
+        from recursion view
+        join results tab on view.resorigtbl=tab.view_id and view.resorigcol=tab.view_column
+      )
+      select
+        sch.nspname as table_schema,
+        tbl.relname as table_name,
+        col.attname as table_column_name,
+        rec.view_schema,
+        rec.view_name,
+        vcol.attname as view_column_name
+      from recursion rec
+      join pg_class tbl on tbl.oid = rec.resorigtbl
+      join pg_attribute col on col.attrelid = tbl.oid and col.attnum = rec.resorigcol
+      join pg_attribute vcol on vcol.attrelid = rec.view_id and vcol.attnum = rec.view_column
+      join pg_namespace sch on sch.oid = tbl.relnamespace
+      join pks_fks using (resorigtbl, resorigcol)
+      order by view_schema, view_name, view_column_name; |]
+
+param :: HE.Value a -> HE.Params a
+param = HE.param . HE.nonNullable
+
+arrayParam :: HE.Value a -> HE.Params [a]
+arrayParam = param . HE.foldableArray . HE.nonNullable
+
+compositeArrayColumn :: HD.Composite a -> HD.Row [a]
+compositeArrayColumn = arrayColumn . HD.composite
+
+compositeField :: HD.Value a -> HD.Composite a
+compositeField = HD.field . HD.nonNullable
+
+column :: HD.Value a -> HD.Row a
+column = HD.column . HD.nonNullable
+
+nullableColumn :: HD.Value a -> HD.Row (Maybe a)
+nullableColumn = HD.column . HD.nullable
+
+arrayColumn :: HD.Value a -> HD.Row [a]
+arrayColumn = column . HD.listArray . HD.nonNullable
@@ -1,18 +1,16 @@
 {-# LANGUAGE DeriveAnyClass #-}
 {-# LANGUAGE DeriveGeneric  #-}

-module PostgREST.SchemaCache.Identifiers
+module PostgREST.DbStructure.Identifiers
  ( QualifiedIdentifier(..)
  , Schema
  , TableName
  , FieldName
-  , AccessSet
  , dumpQi
  , toQi
  ) where

 import qualified Data.Aeson as JSON
-import qualified Data.Set   as S
 import qualified Data.Text  as T

 import Protolude
@@ -24,7 +22,7 @@ data QualifiedIdentifier = QualifiedIdentifier
  { qiSchema :: Schema
  , qiName   :: TableName
  }
-  deriving (Eq, Show, Ord, Generic, JSON.ToJSON, JSON.ToJSONKey)
+  deriving (Eq, Ord, Generic, JSON.ToJSON, JSON.ToJSONKey)

 instance Hashable QualifiedIdentifier

@@ -42,5 +40,3 @@ toQi txt = case T.drop 1 <$> T.breakOn "." txt of
 type Schema = Text
 type TableName = Text
 type FieldName = Text
-
-type AccessSet = S.Set QualifiedIdentifier
@@ -0,0 +1,85 @@
+{-# LANGUAGE DeriveAnyClass #-}
+{-# LANGUAGE DeriveGeneric  #-}
+
+module PostgREST.DbStructure.Proc
+  ( PgType(..)
+  , ProcDescription(..)
+  , ProcParam(..)
+  , ProcVolatility(..)
+  , ProcsMap
+  , RetType(..)
+  , procReturnsScalar
+  , procReturnsSingle
+  , procTableName
+  ) where
+
+import qualified Data.Aeson          as JSON
+import qualified Data.HashMap.Strict as M
+
+import PostgREST.DbStructure.Identifiers (QualifiedIdentifier (..),
+                                          Schema, TableName)
+
+import Protolude
+
+data PgType
+  = Scalar
+  | Composite QualifiedIdentifier
+  deriving (Eq, Ord, Generic, JSON.ToJSON)
+
+data RetType
+  = Single PgType
+  | SetOf PgType
+  deriving (Eq, Ord, Generic, JSON.ToJSON)
+
+data ProcVolatility
+  = Volatile
+  | Stable
+  | Immutable
+  deriving (Eq, Ord, Generic, JSON.ToJSON)
+
+data ProcDescription = ProcDescription
+  { pdSchema      :: Schema
+  , pdName        :: Text
+  , pdDescription :: Maybe Text
+  , pdParams      :: [ProcParam]
+  , pdReturnType  :: RetType
+  , pdVolatility  :: ProcVolatility
+  , pdHasVariadic :: Bool
+  }
+  deriving (Eq, Generic, JSON.ToJSON)
+
+data ProcParam = ProcParam
+  { ppName :: Text
+  , ppType :: Text
+  , ppReq  :: Bool
+  , ppVar  :: Bool
+  }
+  deriving (Eq, Ord, Generic, JSON.ToJSON)
+
+-- Order by least number of params in the case of overloaded functions
+instance Ord ProcDescription where
+  ProcDescription schema1 name1 des1 prms1 rt1 vol1 hasVar1 `compare` ProcDescription schema2 name2 des2 prms2 rt2 vol2 hasVar2
+    | schema1 == schema2 && name1 == name2 && length prms1 < length prms2  = LT
+    | schema2 == schema2 && name1 == name2 && length prms1 > length prms2  = GT
+    | otherwise = (schema1, name1, des1, prms1, rt1, vol1, hasVar1) `compare` (schema2, name2, des2, prms2, rt2, vol2, hasVar2)
+
+-- | A map of all procs, all of which can be overloaded(one entry will have more than one ProcDescription).
+-- | It uses a HashMap for a faster lookup.
+type ProcsMap = M.HashMap QualifiedIdentifier [ProcDescription]
+
+procReturnsScalar :: ProcDescription -> Bool
+procReturnsScalar proc = case proc of
+  ProcDescription{pdReturnType = (Single Scalar)} -> True
+  ProcDescription{pdReturnType = (SetOf Scalar)}  -> True
+  _                                               -> False
+
+procReturnsSingle :: ProcDescription -> Bool
+procReturnsSingle proc = case proc of
+  ProcDescription{pdReturnType = (Single _)} -> True
+  _                                          -> False
+
+procTableName :: ProcDescription -> Maybe TableName
+procTableName proc = case pdReturnType proc of
+  SetOf  (Composite qi) -> Just $ qiName qi
+  Single (Composite qi) -> Just $ qiName qi
+  _                     -> Nothing
@@ -0,0 +1,62 @@
+{-# LANGUAGE DeriveAnyClass #-}
+{-# LANGUAGE DeriveGeneric  #-}
+
+module PostgREST.DbStructure.Relationship
+  ( Cardinality(..)
+  , PrimaryKey(..)
+  , Relationship(..)
+  , Junction(..)
+  , isSelfReference
+  ) where
+
+import qualified Data.Aeson as JSON
+
+import PostgREST.DbStructure.Table (Column (..), Table (..))
+
+import Protolude
+
+
+-- | Relationship between two tables.
+--
+-- The order of the relColumns and relForeignColumns should be maintained to get the
+-- join conditions right.
+--
+-- TODO merge relColumns and relForeignColumns to a tuple or Data.Bimap
+data Relationship = Relationship
+  { relTable          :: Table
+  , relColumns        :: [Column]
+  , relForeignTable   :: Table
+  , relForeignColumns :: [Column]
+  , relCardinality    :: Cardinality
+  }
+  deriving (Eq, Generic, JSON.ToJSON)
+
+-- | The relationship cardinality
+-- | https://en.wikipedia.org/wiki/Cardinality_(data_modeling)
+-- TODO: missing one-to-one
+data Cardinality
+  = O2M FKConstraint -- ^ one-to-many cardinality
+  | M2O FKConstraint -- ^ many-to-one cardinality
+  | M2M Junction     -- ^ many-to-many cardinality
+  deriving (Eq, Generic, JSON.ToJSON)
+
+type FKConstraint = Text
+
+-- | Junction table on an M2M relationship
+data Junction = Junction
+  { junTable       :: Table
+  , junConstraint1 :: FKConstraint
+  , junColumns1    :: [Column]
+  , junConstraint2 :: FKConstraint
+  , junColumns2    :: [Column]
+  }
+  deriving (Eq, Generic, JSON.ToJSON)
+
+isSelfReference :: Relationship -> Bool
+isSelfReference r = relTable r == relForeignTable r
+
+data PrimaryKey = PrimaryKey
+  { pkTable :: Table
+  , pkName  :: Text
+  }
+  deriving (Generic, JSON.ToJSON)
@@ -0,0 +1,55 @@
+{-# LANGUAGE DeriveAnyClass #-}
+{-# LANGUAGE DeriveGeneric  #-}
+
+module PostgREST.DbStructure.Table
+  ( Column(..)
+  , Table(..)
+  , tableQi
+  ) where
+
+import qualified Data.Aeson as JSON
+
+import PostgREST.DbStructure.Identifiers (FieldName,
+                                          QualifiedIdentifier (..),
+                                          Schema, TableName)
+
+import Protolude
+
+
+data Table = Table
+  { tableSchema      :: Schema
+  , tableName        :: TableName
+  , tableDescription :: Maybe Text
+    -- The following fields identify what can be done on the table/view, they're not related to the privileges granted to it
+  , tableInsertable  :: Bool
+  , tableUpdatable   :: Bool
+  , tableDeletable   :: Bool
+  }
+  deriving (Show, Ord, Generic, JSON.ToJSON)
+
+instance Eq Table where
+  Table{tableSchema=s1,tableName=n1} == Table{tableSchema=s2,tableName=n2} = s1 == s2 && n1 == n2
+
+tableQi :: Table -> QualifiedIdentifier
+tableQi Table{tableSchema=s, tableName=n} = QualifiedIdentifier s n
+
+data Column = Column
+  { colTable       :: Table
+  , colName        :: FieldName
+  , colDescription :: Maybe Text
+  , colNullable    :: Bool
+  , colType        :: Text
+  , colMaxLen      :: Maybe Int32
+  , colDefault     :: Maybe Text
+  , colEnum        :: [Text]
+  }
+  deriving (Ord, Generic, JSON.ToJSON)
+
+instance Eq Column where
+  Column{colTable=t1,colName=n1} == Column{colTable=t2,colName=n2} = t1 == t2 && n1 == n2
+
+data PrimaryKey = PrimaryKey
+  { pkTable :: Table
+  , pkName  :: Text
+  }
+  deriving (Generic, JSON.ToJSON)
@@ -11,13 +11,12 @@ module PostgREST.Error
  , PgError(..)
  , Error(..)
  , errorPayload
+  , checkIsFatal
  , singularityError
  ) where

 import qualified Data.Aeson                as JSON
 import qualified Data.ByteString.Char8     as BS
-import qualified Data.FuzzySet             as Fuzzy
-import qualified Data.HashMap.Strict       as HM
 import qualified Data.Text                 as T
 import qualified Data.Text.Encoding        as T
 import qualified Data.Text.Encoding.Error  as T
@@ -30,20 +29,16 @@ import Network.Wai (Response, responseLBS)

 import Network.HTTP.Types.Header (Header)

-import           PostgREST.ApiRequest.Types (ApiRequestError (..),
-                                             QPError (..),
-                                             RangeError (..))
-import           PostgREST.MediaType        (MediaType (..))
-import qualified PostgREST.MediaType        as MediaType
+import           PostgREST.ContentType (ContentType (..))
+import qualified PostgREST.ContentType as ContentType

-import PostgREST.SchemaCache.Identifiers  (QualifiedIdentifier (..),
-                                           Schema)
-import PostgREST.SchemaCache.Relationship (Cardinality (..),
+import PostgREST.DbStructure.Proc         (ProcDescription (..),
+                                           ProcParam (..))
+import PostgREST.DbStructure.Relationship (Cardinality (..),
                                           Junction (..),
-                                           Relationship (..),
-                                           RelationshipsMap)
-import PostgREST.SchemaCache.Routine      (Routine (..),
-                                           RoutineParam (..))
+                                           Relationship (..))
+import PostgREST.DbStructure.Table        (Column (..), Table (..))
+
 import Protolude


@@ -57,301 +52,107 @@ class (JSON.ToJSON a) => PgrstError a where
  errorResponseFor :: a -> Response
  errorResponseFor err = responseLBS (status err) (headers err) $ errorPayload err

+
+
+data ApiRequestError
+  = ActionInappropriate
+  | InvalidRange
+  | InvalidBody ByteString
+  | ParseRequestError Text Text
+  | NoRelBetween Text Text
+  | AmbiguousRelBetween Text Text [Relationship]
+  | AmbiguousRpc [ProcDescription]
+  | NoRpc Text Text [Text] Bool ContentType Bool
+  | InvalidFilters
+  | UnacceptableSchema [Text]
+  | ContentTypeError [ByteString]
+  | UnsupportedVerb                -- Unreachable?
+
 instance PgrstError ApiRequestError where
-  status AmbiguousRelBetween{}   = HTTP.status300
-  status AmbiguousRpc{}          = HTTP.status300
-  status BinaryFieldError{}      = HTTP.status406
-  status MediaTypeError{}        = HTTP.status415
-  status InvalidBody{}           = HTTP.status400
+  status InvalidRange            = HTTP.status416
  status InvalidFilters          = HTTP.status405
-  status InvalidRpcMethod{}      = HTTP.status405
-  status InvalidRange{}          = HTTP.status416
-  status NotFound                = HTTP.status404
-
-  status NoRelBetween{}          = HTTP.status400
+  status (InvalidBody _)         = HTTP.status400
+  status UnsupportedVerb         = HTTP.status405
+  status ActionInappropriate     = HTTP.status405
+  status (ParseRequestError _ _) = HTTP.status400
+  status (NoRelBetween _ _)      = HTTP.status400
+  status AmbiguousRelBetween{}   = HTTP.status300
+  status (AmbiguousRpc _)        = HTTP.status300
  status NoRpc{}                 = HTTP.status404
-  status NotEmbedded{}           = HTTP.status400
-  status PutLimitNotAllowedError = HTTP.status400
-  status QueryParamError{}       = HTTP.status400
-  status RelatedOrderNotToOne{}  = HTTP.status400
-  status SpreadNotToOne{}        = HTTP.status400
-  status UnacceptableFilter{}    = HTTP.status400
-  status UnacceptableSchema{}    = HTTP.status406
-  status UnsupportedMethod{}     = HTTP.status405
-  status LimitNoOrderError       = HTTP.status400
-  status ColumnNotFound{}        = HTTP.status400
+  status (UnacceptableSchema _)  = HTTP.status406
+  status (ContentTypeError _)    = HTTP.status415

-  headers _ = [MediaType.toContentType MTApplicationJSON]
+  headers _ = [ContentType.toHeader CTApplicationJSON]

 instance JSON.ToJSON ApiRequestError where
-  toJSON (QueryParamError (QPError message details)) = JSON.object [
-    "code"    .= ApiRequestErrorCode00,
-    "message" .= message,
-    "details" .= details,
-    "hint"    .= JSON.Null]
-  toJSON (InvalidRpcMethod method) = JSON.object [
-    "code"    .= ApiRequestErrorCode01,
-    "message" .= ("Cannot use the " <> T.decodeUtf8 method <> " method on RPC"),
-    "details" .= JSON.Null,
-    "hint"    .= JSON.Null]
+  toJSON (ParseRequestError message details) = JSON.object [
+    "message" .= message, "details" .= details]
+  toJSON ActionInappropriate = JSON.object [
+    "message" .= ("Bad Request" :: Text)]
  toJSON (InvalidBody errorMessage) = JSON.object [
-    "code"    .= ApiRequestErrorCode02,
-    "message" .= T.decodeUtf8 errorMessage,
-    "details" .= JSON.Null,
-    "hint"    .= JSON.Null]
-  toJSON (InvalidRange rangeError) = JSON.object [
-    "code"    .= ApiRequestErrorCode03,
-    "message" .= ("Requested range not satisfiable" :: Text),
-    "details" .= (case rangeError of
-                   NegativeLimit           -> "Limit should be greater than or equal to zero."
-                   LowerGTUpper            -> "The lower boundary must be lower than or equal to the upper boundary in the Range header."
-                   OutOfBounds lower total -> "An offset of " <> lower <> " was requested, but there are only " <> total <> " rows."),
-    "hint"    .= JSON.Null]
-  toJSON InvalidFilters = JSON.object [
-    "code"    .= ApiRequestErrorCode05,
-    "message" .= ("Filters must include all and only primary key columns with 'eq' operators" :: Text),
-    "details" .= JSON.Null,
-    "hint"    .= JSON.Null]
-  toJSON (UnacceptableSchema schemas) = JSON.object [
-    "code"    .= ApiRequestErrorCode06,
-    "message" .= ("The schema must be one of the following: " <> T.intercalate ", " schemas),
-    "details" .= JSON.Null,
-    "hint"    .= JSON.Null]
-  toJSON (MediaTypeError cts)    = JSON.object [
-    "code"    .= ApiRequestErrorCode07,
-    "message" .= ("None of these media types are available: " <> T.intercalate ", " (map T.decodeUtf8 cts)),
-    "details" .= JSON.Null,
-    "hint"    .= JSON.Null]
-  toJSON NotFound = JSON.object []
-  toJSON (NotEmbedded resource) = JSON.object [
-    "code"    .= ApiRequestErrorCode08,
-    "message" .= ("'" <> resource <> "' is not an embedded resource in this request" :: Text),
-    "details" .= JSON.Null,
-    "hint"    .= ("Verify that '" <> resource <> "' is included in the 'select' query parameter." :: Text)]
-
-  toJSON LimitNoOrderError = JSON.object [
-    "code"    .= ApiRequestErrorCode09,
-    "message" .= ("A 'limit' was applied without an explicit 'order'":: Text),
-    "details" .= JSON.Null,
-    "hint"    .= ("Apply an 'order' using unique column(s)" :: Text)]
-
-  toJSON (BinaryFieldError ct) = JSON.object [
-    "code"    .= ApiRequestErrorCode13,
-    "message" .= ((T.decodeUtf8 (MediaType.toMime ct) <> " requested but more than one column was selected") :: Text),
-    "details" .= JSON.Null,
-    "hint"    .= JSON.Null]
-
-  toJSON PutLimitNotAllowedError = JSON.object [
-    "code"    .= ApiRequestErrorCode14,
-    "message" .= ("limit/offset querystring parameters are not allowed for PUT" :: Text),
-    "details" .= JSON.Null,
-    "hint"    .= JSON.Null]
-
-  toJSON (UnsupportedMethod method) = JSON.object [
-    "code"    .= ApiRequestErrorCode17,
-    "message" .= ("Unsupported HTTP method: " <> T.decodeUtf8 method),
-    "details" .= JSON.Null,
-    "hint"    .= JSON.Null]
-
-  toJSON (RelatedOrderNotToOne origin target) = JSON.object [
-    "code"    .= ApiRequestErrorCode18,
-    "message" .= ("A related order on '" <> target <> "' is not possible" :: Text),
-    "details" .= ("'" <> origin <> "' and '" <> target <> "' do not form a many-to-one or one-to-one relationship" :: Text),
-    "hint"    .= JSON.Null]
-
-  toJSON (SpreadNotToOne origin target) = JSON.object [
-    "code"    .= ApiRequestErrorCode19,
-    "message" .= ("A spread operation on '" <> target <> "' is not possible" :: Text),
-    "details" .= ("'" <> origin <> "' and '" <> target <> "' do not form a many-to-one or one-to-one relationship" :: Text),
-    "hint"    .= JSON.Null]
-
-  toJSON (UnacceptableFilter target) = JSON.object [
-    "code"    .= ApiRequestErrorCode20,
-    "message" .= ("Bad operator on the '" <> target <> "' embedded resource":: Text),
-    "details" .= ("Only is null or not is null filters are allowed on embedded resources":: Text),
-    "hint"    .= JSON.Null]
-
-  toJSON (NoRelBetween parent child embedHint schema allRels) = JSON.object [
-    "code"    .= SchemaCacheErrorCode00,
-    "message" .= ("Could not find a relationship between '" <> parent <> "' and '" <> child <> "' in the schema cache" :: Text),
-    "details" .= ("Searched for a foreign key relationship between '" <> parent <> "' and '" <> child <> maybe mempty ("' using the hint '" <>) embedHint <> "' in the schema '" <> schema <> "', but no matches were found."),
-    "hint"    .= noRelBetweenHint parent child schema allRels]
-
+    "message" .= T.decodeUtf8 errorMessage]
+  toJSON InvalidRange = JSON.object [
+    "message" .= ("HTTP Range error" :: Text)]
+  toJSON (NoRelBetween parent child) = JSON.object [
+    "hint"    .= ("If a new foreign key between these entities was created in the database, try reloading the schema cache." :: Text),
+    "message" .= ("Could not find a relationship between " <> parent <> " and " <> child <> " in the schema cache" :: Text)]
  toJSON (AmbiguousRelBetween parent child rels) = JSON.object [
-    "code"    .= SchemaCacheErrorCode01,
+    "hint"    .= ("Try changing '" <> child <> "' to one of the following: " <> relHint rels <> ". Find the desired relationship in the 'details' key." :: Text),
    "message" .= ("Could not embed because more than one relationship was found for '" <> parent <> "' and '" <> child <> "'" :: Text),
-    "details" .= (compressedRel <$> rels),
-    "hint"    .= ("Try changing '" <> child <> "' to one of the following: " <> relHint rels <> ". Find the desired relationship in the 'details' key." :: Text)]
-  toJSON (NoRpc schema procName argumentKeys hasPreferSingleObject contentType isInvPost allProcs overloadedProcs)  =
-    let func = schema <> "." <> procName
-        prms = T.intercalate ", " argumentKeys
-        prmsMsg = "(" <> prms <> ")"
-        prmsDet = " with parameter" <> (if length argumentKeys > 1 then "s " else " ") <> prms
-        fmtPrms p = if null argumentKeys then " without parameters" else p
-        onlySingleParams = hasPreferSingleObject || (isInvPost && contentType `elem` [MTTextPlain, MTTextXML, MTOctetStream])
-    in JSON.object [
-    "code"    .= SchemaCacheErrorCode02,
-    "message" .= ("Could not find the function " <> func <> (if onlySingleParams then "" else fmtPrms prmsMsg) <> " in the schema cache"),
-    "details" .= ("Searched for the function " <> func <>
-      (case (hasPreferSingleObject, isInvPost, contentType) of
-        (True, _, _)                 -> " with a single json/jsonb parameter"
-        (_, True, MTTextPlain)       -> " with a single unnamed text parameter"
-        (_, True, MTTextXML)         -> " with a single unnamed xml parameter"
-        (_, True, MTOctetStream)     -> " with a single unnamed bytea parameter"
-        (_, True, MTApplicationJSON) -> fmtPrms prmsDet <> " or with a single unnamed json/jsonb parameter"
-        _                            -> fmtPrms prmsDet) <>
-      ", but no matches were found in the schema cache."),
-    -- The hint will be null in the case of single unnamed parameter functions
-    "hint"    .= if onlySingleParams
-                 then Nothing
-                 else noRpcHint schema procName argumentKeys allProcs overloadedProcs ]
+    "details" .= (compressedRel <$> rels) ]
  toJSON (AmbiguousRpc procs)  = JSON.object [
-    "code"    .= SchemaCacheErrorCode03,
-    "message" .= ("Could not choose the best candidate function between: " <> T.intercalate ", " [pdSchema p <> "." <> pdName p <> "(" <> T.intercalate ", " [ppName a <> " => " <> ppType a | a <- pdParams p] <> ")" | p <- procs]),
-    "details" .= JSON.Null,
-    "hint"    .= ("Try renaming the parameters or the function itself in the database so function overloading can be resolved" :: Text)]
-  toJSON (ColumnNotFound relName colName) = JSON.object [
-    "code"    .= SchemaCacheErrorCode04,
-    "message" .= ("Column '" <> colName <> "' of relation '" <> relName <> "' does not exist" :: Text),
-    "details" .= JSON.Null,
-    "hint"    .= JSON.Null]
-
-- |
-- If no relationship is found then:
--
-- Looks for parent suggestions if parent not found
-- Looks for child suggestions if parent is found but child is not
-- Gives no suggestions if both are found (it means that there is a problem with the embed hint)
--
-- >>> :set -Wno-missing-fields
-- >>> let qi t = QualifiedIdentifier "api" t
-- >>> let rel ft = Relationship{relForeignTable = qi ft}
-- >>> let rels = HM.fromList [((qi "films", "api"), [rel "directors", rel "roles", rel "actors"])]
--
-- >>> noRelBetweenHint "film" "directors" "api" rels
-- Just "Perhaps you meant 'films' instead of 'film'."
--
-- >>> noRelBetweenHint "films" "role" "api" rels
-- Just "Perhaps you meant 'roles' instead of 'role'."
--
-- >>> noRelBetweenHint "films" "role" "api" rels
-- Just "Perhaps you meant 'roles' instead of 'role'."
--
-- >>> noRelBetweenHint "films" "actors" "api" rels
-- Nothing
--
-- >>> noRelBetweenHint "noclosealternative" "roles" "api" rels
-- Nothing
--
-- >>> noRelBetweenHint "films" "noclosealternative" "api" rels
-- Nothing
--
-- >>> noRelBetweenHint "films" "noclosealternative" "noclosealternative" rels
-- Nothing
--
-noRelBetweenHint :: Text -> Text -> Schema -> RelationshipsMap -> Maybe Text
-noRelBetweenHint parent child schema allRels = ("Perhaps you meant '" <>) <$>
-  if isJust findParent
-    then (<> "' instead of '" <> child <> "'.") <$> suggestChild
-    else (<> "' instead of '" <> parent <> "'.") <$> suggestParent
-  where
-    findParent = HM.lookup (QualifiedIdentifier schema parent, schema) allRels
-    fuzzySetOfParents  = Fuzzy.fromList [qiName (fst p) | p <- HM.keys allRels, snd p == schema]
-    fuzzySetOfChildren = Fuzzy.fromList [qiName (relForeignTable c) | c <- fromMaybe [] findParent]
-    suggestParent = Fuzzy.getOne fuzzySetOfParents parent
-    -- Do not give suggestion if the child is found in the relations (weight = 1.0)
-    suggestChild  = headMay [snd k | k <- Fuzzy.get fuzzySetOfChildren child, fst k < 1.0]
-
-- |
-- If no function is found with the given name, it does a fuzzy search to all the functions
-- in the same schema and shows the best match as hint.
--
-- >>> :set -Wno-missing-fields
-- >>> let procs = [(QualifiedIdentifier "api" "test"), (QualifiedIdentifier "api" "another"), (QualifiedIdentifier "private" "other")]
--
-- >>> noRpcHint "api" "testt" ["val", "param", "name"] procs []
-- Just "Perhaps you meant to call the function api.test"
--
-- >>> noRpcHint "api" "other" [] procs []
-- Just "Perhaps you meant to call the function api.another"
--
-- >>> noRpcHint "api" "noclosealternative" [] procs []
-- Nothing
--
-- If a function is found with the given name, but no params match, then it does a fuzzy search
-- to all the overloaded functions' params using the form "param1, param2, param3, ..."
-- and shows the best match as hint.
--
-- >>> let procsDesc = [Function {pdParams = [RoutineParam {ppName="val"}, RoutineParam {ppName="param"}, RoutineParam {ppName="name"}]}, Function {pdParams = [RoutineParam {ppName="id"}, RoutineParam {ppName="attr"}]}]
--
-- >>> noRpcHint "api" "test" ["vall", "pqaram", "nam"] procs procsDesc
-- Just "Perhaps you meant to call the function api.test(name, param, val)"
--
-- >>> noRpcHint "api" "test" ["val", "param"] procs procsDesc
-- Just "Perhaps you meant to call the function api.test(name, param, val)"
--
-- >>> noRpcHint "api" "test" ["id", "attrs"] procs procsDesc
-- Just "Perhaps you meant to call the function api.test(attr, id)"
--
-- >>> noRpcHint "api" "test" ["id"] procs procsDesc
-- Just "Perhaps you meant to call the function api.test(attr, id)"
--
-- >>> noRpcHint "api" "test" ["noclosealternative"] procs procsDesc
-- Nothing
--
-noRpcHint :: Text -> Text -> [Text] -> [QualifiedIdentifier] -> [Routine] -> Maybe Text
-noRpcHint schema procName params allProcs overloadedProcs =
-  fmap (("Perhaps you meant to call the function " <> schema <> ".") <>) possibleProcs
-  where
-    fuzzySetOfProcs  = Fuzzy.fromList [qiName k | k <- allProcs, qiSchema k == schema]
-    fuzzySetOfParams = Fuzzy.fromList $ listToText <$> [[ppName prm | prm <- pdParams ov] | ov <- overloadedProcs]
-    -- Cannot do a fuzzy search like: Fuzzy.getOne [[Text]] [Text], where [[Text]] is the list of params for each
-    -- overloaded function and [Text] the given params. This converts those lists to text to make fuzzy search possible.
-    -- E.g. ["val", "param", "name"] into "(name, param, val)"
-    listToText       = ("(" <>) . (<> ")") . T.intercalate ", " . sort
-    possibleProcs
-      | null overloadedProcs = Fuzzy.getOne fuzzySetOfProcs procName
-      | otherwise            = (procName <>) <$> Fuzzy.getOne fuzzySetOfParams (listToText params)
+    "hint"    .= ("Try renaming the parameters or the function itself in the database so function overloading can be resolved" :: Text),
+    "message" .= ("Could not choose the best candidate function between: " <> T.intercalate ", " [pdSchema p <> "." <> pdName p <> "(" <> T.intercalate ", " [ppName a <> " => " <> ppType a | a <- pdParams p] <> ")" | p <- procs])]
+  toJSON (NoRpc schema procName argumentKeys hasPreferSingleObject contentType isInvPost)  =
+    let prms = "(" <> T.intercalate ", " argumentKeys <> ")" in JSON.object [
+    "hint"    .= ("If a new function was created in the database with this name and parameters, try reloading the schema cache." :: Text),
+    "message" .= ("Could not find the " <> schema <> "." <> procName <>
+      (case (hasPreferSingleObject, isInvPost, contentType) of
+        (True, _, _)                 -> " function with a single json or jsonb parameter"
+        (_, True, CTTextPlain)       -> " function with a single unnamed text parameter"
+        (_, True, CTOctetStream)     -> " function with a single unnamed bytea parameter"
+        (_, True, CTApplicationJSON) -> prms <> " function or the " <> schema <> "." <> procName <>" function with a single unnamed json or jsonb parameter"
+        _                            -> prms <> " function") <>
+      " in the schema cache")]
+  toJSON UnsupportedVerb = JSON.object [
+    "message" .= ("Unsupported HTTP verb" :: Text)]
+  toJSON InvalidFilters = JSON.object [
+    "message" .= ("Filters must include all and only primary key columns with 'eq' operators" :: Text)]
+  toJSON (UnacceptableSchema schemas) = JSON.object [
+    "message" .= ("The schema must be one of the following: " <> T.intercalate ", " schemas)]
+  toJSON (ContentTypeError cts)    = JSON.object [
+    "message" .= ("None of these Content-Types are available: " <> T.intercalate ", " (map T.decodeUtf8 cts))]

 compressedRel :: Relationship -> JSON.Value
-- An ambiguousness error cannot happen for computed relationships TODO refactor so this mempty is not needed
-compressedRel ComputedRelationship{} = JSON.object mempty
 compressedRel Relationship{..} =
  let
    fmtEls els = "(" <> T.intercalate ", " els <> ")"
  in
  JSON.object $
-    ("embedding" .= (qiName relTable <> " with " <> qiName relForeignTable :: Text))
+    ("embedding" .= (tableName relTable <> " with " <> tableName relForeignTable :: Text))
    : case relCardinality of
        M2M Junction{..} -> [
            "cardinality" .= ("many-to-many" :: Text)
-          , "relationship" .= (qiName junTable <> " using " <> junConstraint1 <> fmtEls (snd <$> junColsSource) <> " and " <> junConstraint2 <> fmtEls (snd <$> junColsTarget))
+          , "relationship" .= (tableName junTable <> " using " <> junConstraint1 <> fmtEls (colName <$> junColumns1) <> " and " <> junConstraint2 <> fmtEls (colName <$> junColumns2))
          ]
-        M2O cons relColumns -> [
+        M2O cons -> [
            "cardinality" .= ("many-to-one" :: Text)
-          , "relationship" .= (cons <> " using " <> qiName relTable <> fmtEls (fst <$> relColumns) <> " and " <> qiName relForeignTable <> fmtEls (snd <$> relColumns))
+          , "relationship" .= (cons <> " using " <> tableName relTable <> fmtEls (colName <$> relColumns) <> " and " <> tableName relForeignTable <> fmtEls (colName <$> relForeignColumns))
          ]
-        O2O cons relColumns -> [
-            "cardinality" .= ("one-to-one" :: Text)
-          , "relationship" .= (cons <> " using " <> qiName relTable <> fmtEls (fst <$> relColumns) <> " and " <> qiName relForeignTable <> fmtEls (snd <$> relColumns))
-          ]
-        O2M cons relColumns -> [
+        O2M cons -> [
            "cardinality" .= ("one-to-many" :: Text)
-          , "relationship" .= (cons <> " using " <> qiName relTable <> fmtEls (fst <$> relColumns) <> " and " <> qiName relForeignTable <> fmtEls (snd <$> relColumns))
+          , "relationship" .= (cons <> " using " <> tableName relTable <> fmtEls (colName <$> relColumns) <> " and " <> tableName relForeignTable <> fmtEls (colName <$> relForeignColumns))
          ]

 relHint :: [Relationship] -> Text
 relHint rels = T.intercalate ", " (hintList <$> rels)
  where
    hintList Relationship{..} =
-      let buildHint rel = "'" <> qiName relForeignTable <> "!" <> rel <> "'" in
+      let buildHint rel = "'" <> tableName relForeignTable <> "!" <> rel <> "'" in
      case relCardinality of
-        M2M Junction{..} -> buildHint (qiName junTable)
-        M2O cons _       -> buildHint cons
-        O2O cons _       -> buildHint cons
-        O2M cons _       -> buildHint cons
-    -- An ambiguousness error cannot happen for computed relationships TODO refactor so this mempty is not needed
-    hintList ComputedRelationship{} = mempty
+        M2M Junction{..} -> buildHint (tableName junTable)
+        M2O cons         -> buildHint cons
+        O2M cons         -> buildHint cons

 data PgError = PgError Authenticated SQL.UsageError
 type Authenticated = Bool
@@ -361,55 +162,61 @@ instance PgrstError PgError where

  headers err =
    if status err == HTTP.status401
-       then [MediaType.toContentType MTApplicationJSON, ("WWW-Authenticate", "Bearer") :: Header]
-       else [MediaType.toContentType MTApplicationJSON]
+       then [ContentType.toHeader CTApplicationJSON, ("WWW-Authenticate", "Bearer") :: Header]
+       else [ContentType.toHeader CTApplicationJSON]

 instance JSON.ToJSON PgError where
  toJSON (PgError _ usageError) = JSON.toJSON usageError

 instance JSON.ToJSON SQL.UsageError where
-  toJSON (SQL.ConnectionUsageError e) = JSON.object [
-    "code"    .= ConnectionErrorCode00,
+  toJSON (SQL.ConnectionError e) = JSON.object [
+    "code"    .= ("" :: Text),
    "message" .= ("Database connection error. Retrying the connection." :: Text),
-    "details" .= (T.decodeUtf8With T.lenientDecode $ fromMaybe "" e :: Text),
-    "hint"    .= JSON.Null]
-  toJSON (SQL.SessionUsageError e) = JSON.toJSON e -- SQL.Error
-  toJSON SQL.AcquisitionTimeoutUsageError = JSON.object [
-    "code"    .= ConnectionErrorCode03,
-    "message" .= ("Timed out acquiring connection from connection pool." :: Text),
-    "details" .= JSON.Null,
-    "hint"    .= JSON.Null]
+    "details" .= (T.decodeUtf8With T.lenientDecode $ fromMaybe "" e :: Text)]
+  toJSON (SQL.SessionError e) = JSON.toJSON e -- SQL.Error

 instance JSON.ToJSON SQL.QueryError where
  toJSON (SQL.QueryError _ _ e) = JSON.toJSON e

 instance JSON.ToJSON SQL.CommandError where
-  toJSON (SQL.ResultError (SQL.ServerError c m d h _p)) = JSON.object [
-    "code"     .= (T.decodeUtf8 c      :: Text),
-    "message"  .= (T.decodeUtf8 m      :: Text),
-    "details"  .= (fmap T.decodeUtf8 d :: Maybe Text),
-    "hint"     .= (fmap T.decodeUtf8 h :: Maybe Text)]
+  toJSON (SQL.ResultError (SQL.ServerError c m d h)) = case BS.unpack c of
+    'P':'T':_ -> JSON.object [
+        "details" .= fmap T.decodeUtf8 d,
+        "hint"    .= fmap T.decodeUtf8 h]

-  toJSON (SQL.ResultError resultError) = JSON.object [
-    "code"    .= InternalErrorCode00,
-    "message" .= (show resultError :: Text),
-    "details" .= JSON.Null,
-    "hint"    .= JSON.Null]
+    _         -> JSON.object [
+        "code"    .= (T.decodeUtf8 c      :: Text),
+        "message" .= (T.decodeUtf8 m      :: Text),
+        "details" .= (fmap T.decodeUtf8 d :: Maybe Text),
+        "hint"    .= (fmap T.decodeUtf8 h :: Maybe Text)]

+  toJSON (SQL.ResultError (SQL.UnexpectedResult m)) = JSON.object [
+    "message" .= (m :: Text)]
+  toJSON (SQL.ResultError (SQL.RowError i SQL.EndOfInput)) = JSON.object [
+    "message" .= ("Row error: end of input" :: Text),
+    "details" .= ("Attempt to parse more columns than there are in the result" :: Text),
+    "hint"    .= (("Row number " <> show i) :: Text)]
+  toJSON (SQL.ResultError (SQL.RowError i SQL.UnexpectedNull)) = JSON.object [
+    "message" .= ("Row error: unexpected null" :: Text),
+    "details" .= ("Attempt to parse a NULL as some value." :: Text),
+    "hint"    .= (("Row number " <> show i) :: Text)]
+  toJSON (SQL.ResultError (SQL.RowError i (SQL.ValueError d))) = JSON.object [
+    "message" .= ("Row error: Wrong value parser used" :: Text),
+    "details" .= d,
+    "hint"    .= (("Row number " <> show i) :: Text)]
+  toJSON (SQL.ResultError (SQL.UnexpectedAmountOfRows i)) = JSON.object [
+    "message" .= ("Unexpected amount of rows" :: Text),
+    "details" .= i]
  toJSON (SQL.ClientError d) = JSON.object [
-    "code"    .= ConnectionErrorCode01,
    "message" .= ("Database client error. Retrying the connection." :: Text),
-    "details" .= (fmap T.decodeUtf8 d :: Maybe Text),
-    "hint"    .= JSON.Null]
-
+    "details" .= (fmap T.decodeUtf8 d :: Maybe Text)]

 pgErrorStatus :: Bool -> SQL.UsageError -> HTTP.Status
-pgErrorStatus _      (SQL.ConnectionUsageError _) = HTTP.status503
-pgErrorStatus _      SQL.AcquisitionTimeoutUsageError = HTTP.status504
-pgErrorStatus _      (SQL.SessionUsageError (SQL.QueryError _ _ (SQL.ClientError _)))      = HTTP.status503
-pgErrorStatus authed (SQL.SessionUsageError (SQL.QueryError _ _ (SQL.ResultError rError))) =
+pgErrorStatus _      (SQL.ConnectionError _)                                      = HTTP.status503
+pgErrorStatus _      (SQL.SessionError (SQL.QueryError _ _ (SQL.ClientError _)))      = HTTP.status503
+pgErrorStatus authed (SQL.SessionError (SQL.QueryError _ _ (SQL.ResultError rError))) =
  case rError of
-    (SQL.ServerError c m _ _ _) ->
+    (SQL.ServerError c m _ _) ->
      case BS.unpack c of
        '0':'8':_ -> HTTP.status503 -- pg connection err
        '0':'9':_ -> HTTP.status500 -- triggered action exception
@@ -428,7 +235,6 @@ pgErrorStatus authed (SQL.SessionUsageError (SQL.QueryError _ _ (SQL.ResultError
        '5':'3':_ -> HTTP.status503 -- insufficient resources
        '5':'4':_ -> HTTP.status413 -- too complex
        '5':'5':_ -> HTTP.status500 -- obj not on prereq state
-        '5':'7':'P':'0':'1':_ -> HTTP.status503 -- terminating connection due to administrator command
        '5':'7':_ -> HTTP.status500 -- operator intervention
        '5':'8':_ -> HTTP.status500 -- system error
        'F':'0':_ -> HTTP.status500 -- conf file error
@@ -436,9 +242,7 @@ pgErrorStatus authed (SQL.SessionUsageError (SQL.QueryError _ _ (SQL.ResultError
        "P0001"   -> HTTP.status400 -- default code for "raise"
        'P':'0':_ -> HTTP.status500 -- PL/pgSQL Error
        'X':'X':_ -> HTTP.status500 -- internal Error
-        "42883"-> if BS.isPrefixOf "function xmlagg(" m
-          then HTTP.status406
-          else HTTP.status404 -- undefined function
+        "42883"   -> HTTP.status404 -- undefined function
        "42P01"   -> HTTP.status404 -- undefined table
        "42501"   -> if authed then HTTP.status403 else HTTP.status401 -- insufficient privilege
        'P':'T':n -> fromMaybe HTTP.status500 (HTTP.mkStatus <$> readMaybe n <*> pure m)
@@ -446,93 +250,89 @@ pgErrorStatus authed (SQL.SessionUsageError (SQL.QueryError _ _ (SQL.ResultError

    _                       -> HTTP.status500

+checkIsFatal :: PgError -> Maybe Text
+checkIsFatal (PgError _ (SQL.ConnectionError e))
+  | isAuthFailureMessage = Just $ toS failureMessage
+  | otherwise = Nothing
+  where isAuthFailureMessage = "FATAL:  password authentication failed" `isPrefixOf` failureMessage
+        failureMessage = BS.unpack $ fromMaybe mempty e
+checkIsFatal (PgError _ (SQL.SessionError (SQL.QueryError _ _ (SQL.ResultError serverError))))
+  = case serverError of
+      -- Check for a syntax error (42601 is the pg code). This would mean the error is on our part somehow, so we treat it as fatal.
+      SQL.ServerError "42601" _ _ _
+        -> Just "Hint: This is probably a bug in PostgREST, please report it at https://github.com/PostgREST/postgrest/issues"
+      -- Check for a "prepared statement <name> already exists" error (Code 42P05: duplicate_prepared_statement).
+      -- This would mean that a connection pooler in transaction mode is being used
+      -- while prepared statements are enabled in the PostgREST configuration,
+      -- both of which are incompatible with each other.
+      SQL.ServerError "42P05" _ _ _
+        -> Just "Hint: If you are using connection poolers in transaction mode, try setting db-prepared-statements to false."
+      -- Check for a "transaction blocks not allowed in statement pooling mode" error (Code 08P01: protocol_violation).
+      -- This would mean that a connection pooler in statement mode is being used which is not supported in PostgREST.
+      SQL.ServerError "08P01" "transaction blocks not allowed in statement pooling mode" _ _
+        -> Just "Hint: Connection poolers in statement mode are not supported."
+      _ -> Nothing
+checkIsFatal _ = Nothing


 data Error
-  = ApiRequestError ApiRequestError
-  | GucHeadersError
+  = GucHeadersError
  | GucStatusError
-  | JwtTokenInvalid Text
-  | JwtTokenMissing
-  | JwtTokenRequired
-  | NoSchemaCacheError
-  | OffLimitsChangesError Int64 Integer
-  | PgErr PgError
+  | BinaryFieldError ContentType
+  | ConnectionLostError
  | PutMatchingPkError
+  | PutRangeNotAllowedError
+  | JwtTokenMissing
+  | JwtTokenInvalid Text
  | SingularityError Integer
+  | NotFound
+  | ApiRequestError ApiRequestError
+  | PgErr PgError

 instance PgrstError Error where
-  status (ApiRequestError err)   = status err
  status GucHeadersError         = HTTP.status500
  status GucStatusError          = HTTP.status500
-  status JwtTokenInvalid{}       = HTTP.unauthorized401
-  status JwtTokenMissing         = HTTP.status500
-  status JwtTokenRequired        = HTTP.unauthorized401
-  status NoSchemaCacheError      = HTTP.status503
-  status OffLimitsChangesError{} = HTTP.status400
-  status (PgErr err)             = status err
+  status (BinaryFieldError _)    = HTTP.status406
+  status ConnectionLostError     = HTTP.status503
  status PutMatchingPkError      = HTTP.status400
-  status SingularityError{}      = HTTP.status406
+  status PutRangeNotAllowedError = HTTP.status400
+  status JwtTokenMissing         = HTTP.status500
+  status (JwtTokenInvalid _)     = HTTP.unauthorized401
+  status (SingularityError _)    = HTTP.status406
+  status NotFound                = HTTP.status404
+  status (PgErr err)             = status err
+  status (ApiRequestError err)   = status err

-  headers (ApiRequestError err)  = headers err
-  headers (JwtTokenInvalid m)    = [MediaType.toContentType MTApplicationJSON, invalidTokenHeader m]
-  headers JwtTokenRequired       = [MediaType.toContentType MTApplicationJSON, requiredTokenHeader]
-  headers (PgErr err)            = headers err
-  headers SingularityError{}     = [MediaType.toContentType (MTSingularJSON False)]
-  headers _                      = [MediaType.toContentType MTApplicationJSON]
+  headers (SingularityError _)     = [ContentType.toHeader CTSingularJSON]
+  headers (JwtTokenInvalid m)      = [ContentType.toHeader CTApplicationJSON, invalidTokenHeader m]
+  headers (PgErr err)              = headers err
+  headers (ApiRequestError err)    = headers err
+  headers _                        = [ContentType.toHeader CTApplicationJSON]

 instance JSON.ToJSON Error where
-  toJSON NoSchemaCacheError = JSON.object [
-      "code"    .= ConnectionErrorCode02,
-      "message" .= ("Could not query the database for the schema cache. Retrying." :: Text),
-      "details" .= JSON.Null,
-      "hint"    .= JSON.Null]
+  toJSON GucHeadersError           = JSON.object [
+    "message" .= ("response.headers guc must be a JSON array composed of objects with a single key and a string value" :: Text)]
+  toJSON GucStatusError           = JSON.object [
+    "message" .= ("response.status guc must be a valid status code" :: Text)]
+  toJSON (BinaryFieldError ct)          = JSON.object [
+    "message" .= ((T.decodeUtf8 (ContentType.toMime ct) <> " requested but more than one column was selected") :: Text)]
+  toJSON ConnectionLostError       = JSON.object [
+    "message" .= ("Database connection lost. Retrying the connection." :: Text)]

-  toJSON JwtTokenMissing = JSON.object [
-      "code"    .= JWTErrorCode00,
-      "message" .= ("Server lacks JWT secret" :: Text),
-      "details" .= JSON.Null,
-      "hint"    .= JSON.Null]
-  toJSON (JwtTokenInvalid message) = JSON.object [
-      "code"    .= JWTErrorCode01,
-      "message" .= (message :: Text),
-      "details" .= JSON.Null,
-      "hint"    .= JSON.Null]
-  toJSON JwtTokenRequired = JSON.object [
-      "code"    .= JWTErrorCode02,
-      "message" .= ("Anonymous access is disabled" :: Text),
-      "details" .= JSON.Null,
-      "hint"    .= JSON.Null]
+  toJSON PutRangeNotAllowedError   = JSON.object [
+    "message" .= ("Range header and limit/offset querystring parameters are not allowed for PUT" :: Text)]
+  toJSON PutMatchingPkError        = JSON.object [
+    "message" .= ("Payload values do not match URL in primary key column(s)" :: Text)]

-  toJSON (OffLimitsChangesError n maxs) = JSON.object [
-      "code"    .= ApiRequestErrorCode10,
-      "message" .= ("The maximum number of rows allowed to change was surpassed" :: Text),
-      "details" .= T.unwords ["Results contain", show n, "rows changed but the maximum number allowed is", show maxs],
-      "hint"    .= JSON.Null]
-
-  toJSON GucHeadersError = JSON.object [
-    "code"    .= ApiRequestErrorCode11,
-    "message" .= ("response.headers guc must be a JSON array composed of objects with a single key and a string value" :: Text),
-    "details" .= JSON.Null,
-    "hint"    .= JSON.Null]
-  toJSON GucStatusError = JSON.object [
-    "code"    .= ApiRequestErrorCode12,
-    "message" .= ("response.status guc must be a valid status code" :: Text),
-    "details" .= JSON.Null,
-    "hint"    .= JSON.Null]
-
-  toJSON PutMatchingPkError = JSON.object [
-    "code"    .= ApiRequestErrorCode15,
-    "message" .= ("Payload values do not match URL in primary key column(s)" :: Text),
-    "details" .= JSON.Null,
-    "hint"    .= JSON.Null]
-
-  toJSON (SingularityError n) = JSON.object [
-    "code"    .= ApiRequestErrorCode16,
+  toJSON (SingularityError n)      = JSON.object [
    "message" .= ("JSON object requested, multiple (or no) rows returned" :: Text),
-    "details" .= T.unwords ["The result contains", show n, "rows"],
-    "hint"    .= JSON.Null]
+    "details" .= T.unwords ["Results contain", show n, "rows,", T.decodeUtf8 (ContentType.toMime CTSingularJSON), "requires 1 row"]]

+  toJSON JwtTokenMissing           = JSON.object [
+    "message" .= ("Server lacks JWT secret" :: Text)]
+  toJSON (JwtTokenInvalid message) = JSON.object [
+    "message" .= (message :: Text)]
+  toJSON NotFound = JSON.object []
  toJSON (PgErr err) = JSON.toJSON err
  toJSON (ApiRequestError err) = JSON.toJSON err

@@ -540,96 +340,5 @@ invalidTokenHeader :: Text -> Header
 invalidTokenHeader m =
  ("WWW-Authenticate", "Bearer error=\"invalid_token\", " <> "error_description=" <> encodeUtf8 (show m))

-requiredTokenHeader :: Header
-requiredTokenHeader = ("WWW-Authenticate", "Bearer")
-
 singularityError :: (Integral a) => a -> Error
 singularityError = SingularityError . toInteger
-
-- Error codes are grouped by common modules or characteristics
-data ErrorCode
-  -- PostgreSQL connection errors
-  = ConnectionErrorCode00
-  | ConnectionErrorCode01
-  | ConnectionErrorCode02
-  | ConnectionErrorCode03
-  -- API Request errors
-  | ApiRequestErrorCode00
-  | ApiRequestErrorCode01
-  | ApiRequestErrorCode02
-  | ApiRequestErrorCode03
-  | ApiRequestErrorCode04 -- no longer used (used to be mapped to ParseRequestError)
-  | ApiRequestErrorCode05
-  | ApiRequestErrorCode06
-  | ApiRequestErrorCode07
-  | ApiRequestErrorCode08
-  | ApiRequestErrorCode09
-  | ApiRequestErrorCode10
-  | ApiRequestErrorCode11
-  | ApiRequestErrorCode12
-  | ApiRequestErrorCode13
-  | ApiRequestErrorCode14
-  | ApiRequestErrorCode15
-  | ApiRequestErrorCode16
-  | ApiRequestErrorCode17
-  | ApiRequestErrorCode18
-  | ApiRequestErrorCode19
-  | ApiRequestErrorCode20
-  -- Schema Cache errors
-  | SchemaCacheErrorCode00
-  | SchemaCacheErrorCode01
-  | SchemaCacheErrorCode02
-  | SchemaCacheErrorCode03
-  | SchemaCacheErrorCode04
-  -- JWT authentication errors
-  | JWTErrorCode00
-  | JWTErrorCode01
-  | JWTErrorCode02
-  -- Internal errors related to the Hasql library
-  | InternalErrorCode00
-
-instance JSON.ToJSON ErrorCode where
-  toJSON e = JSON.toJSON (buildErrorCode e)
-
-- New group of errors will be added at the end of all the groups and will have the next prefix in the sequence
-- New errors are added at the end of the group they belong to and will have the next code in the sequence
-buildErrorCode :: ErrorCode -> Text
-buildErrorCode code = "PGRST" <> case code of
-  ConnectionErrorCode00  -> "000"
-  ConnectionErrorCode01  -> "001"
-  ConnectionErrorCode02  -> "002"
-  ConnectionErrorCode03  -> "003"
-
-  ApiRequestErrorCode00  -> "100"
-  ApiRequestErrorCode01  -> "101"
-  ApiRequestErrorCode02  -> "102"
-  ApiRequestErrorCode03  -> "103"
-  ApiRequestErrorCode04  -> "104"
-  ApiRequestErrorCode05  -> "105"
-  ApiRequestErrorCode06  -> "106"
-  ApiRequestErrorCode07  -> "107"
-  ApiRequestErrorCode08  -> "108"
-  ApiRequestErrorCode09  -> "109"
-  ApiRequestErrorCode10  -> "110"
-  ApiRequestErrorCode11  -> "111"
-  ApiRequestErrorCode12  -> "112"
-  ApiRequestErrorCode13  -> "113"
-  ApiRequestErrorCode14  -> "114"
-  ApiRequestErrorCode15  -> "115"
-  ApiRequestErrorCode16  -> "116"
-  ApiRequestErrorCode17  -> "117"
-  ApiRequestErrorCode18  -> "118"
-  ApiRequestErrorCode19  -> "119"
-  ApiRequestErrorCode20  -> "120"
-
-  SchemaCacheErrorCode00 -> "200"
-  SchemaCacheErrorCode01 -> "201"
-  SchemaCacheErrorCode02 -> "202"
-  SchemaCacheErrorCode03 -> "203"
-  SchemaCacheErrorCode04 -> "204"
-
-  JWTErrorCode00         -> "300"
-  JWTErrorCode01         -> "301"
-  JWTErrorCode02         -> "302"
-
-  InternalErrorCode00    -> "X00"
@@ -1,12 +1,12 @@
-module PostgREST.Response.GucHeader
+module PostgREST.GucHeader
  ( GucHeader
  , unwrapGucHeader
+  , addHeadersIfNotIncluded
  ) where

 import qualified Data.Aeson           as JSON
-import qualified Data.Aeson.Key       as K
-import qualified Data.Aeson.KeyMap    as KM
 import qualified Data.CaseInsensitive as CI
+import qualified Data.HashMap.Strict  as M

 import Network.HTTP.Types.Header (Header)

@@ -21,10 +21,16 @@ newtype GucHeader = GucHeader (CI.CI ByteString, ByteString)

 instance JSON.FromJSON GucHeader where
  parseJSON (JSON.Object o) =
-    case KM.toList o of
-      [(k, JSON.String s)] -> pure $ GucHeader (CI.mk $ toUtf8 $ K.toText k, toUtf8 s)
+    case M.toList o of
+      [(k, JSON.String s)] -> pure $ GucHeader (CI.mk $ toUtf8 k, toUtf8 s)
      _ -> mzero
  parseJSON _ = mzero

 unwrapGucHeader :: GucHeader -> Header
 unwrapGucHeader (GucHeader (k, v)) = (k, v)
+
+-- | Add headers not already included to allow the user to override them instead of duplicating them
+addHeadersIfNotIncluded :: [Header] -> [Header] -> [Header]
+addHeadersIfNotIncluded newHeaders initialHeaders =
+  filter (\(nk, _) -> isNothing $ find (\(ik, _) -> ik == nk) initialHeaders) newHeaders ++
+  initialHeaders
@@ -10,8 +10,7 @@ import qualified Network.Wai.Middleware.RequestLogger as Wai
 import Network.HTTP.Types.Status (status400, status500)
 import System.IO.Unsafe          (unsafePerformIO)

-import qualified PostgREST.Auth   as Auth
-import           PostgREST.Config (LogLevel (..))
+import PostgREST.Config (LogLevel (..))

 import Protolude

@@ -26,5 +25,4 @@ middleware logLevel = case logLevel of
      { Wai.outputFormat = Wai.ApacheWithSettings $
          Wai.defaultApacheSettings
            & Wai.setApacheRequestFilter (\_ res -> filterStatus $ Wai.responseStatus res)
-            & Wai.setApacheUserGetter Auth.getRole
      }
@@ -1,169 +0,0 @@
-{-# LANGUAGE DuplicateRecordFields #-}
-
-module PostgREST.MediaType
-  ( MediaType(..)
-  , MTPlanOption (..)
-  , MTPlanFormat (..)
-  , toContentType
-  , toMime
-  , decodeMediaType
-  ) where
-
-import qualified Data.ByteString          as BS
-import qualified Data.ByteString.Internal as BS (c2w)
-
-import Network.HTTP.Types.Header (Header, hContentType)
-
-import Protolude
-
-- | Enumeration of currently supported media types
-data MediaType
-  = MTApplicationJSON
-  | MTArrayJSONStrip
-  | MTSingularJSON Bool
-  | MTGeoJSON
-  | MTTextCSV
-  | MTTextPlain
-  | MTTextXML
-  | MTOpenAPI
-  | MTUrlEncoded
-  | MTOctetStream
-  | MTAny
-  | MTOther ByteString
-  -- TODO MTPlan should only have its options as [Text]. Its ResultAggregate should have the typed attributes.
-  | MTPlan MediaType MTPlanFormat [MTPlanOption]
-  deriving Show
-instance Eq MediaType where
-  MTApplicationJSON    == MTApplicationJSON = True
-  MTArrayJSONStrip     == MTArrayJSONStrip  = True
-  MTSingularJSON x     == MTSingularJSON y  = x == y
-  MTGeoJSON            == MTGeoJSON         = True
-  MTTextCSV            == MTTextCSV         = True
-  MTTextPlain          == MTTextPlain       = True
-  MTTextXML            == MTTextXML         = True
-  MTOpenAPI            == MTOpenAPI         = True
-  MTUrlEncoded         == MTUrlEncoded      = True
-  MTOctetStream        == MTOctetStream     = True
-  MTAny                == MTAny             = True
-  MTOther x            == MTOther y         = x == y
-  MTPlan{}             == MTPlan{}          = True
-  _                    == _                 = False
-
-data MTPlanOption
-  = PlanAnalyze | PlanVerbose | PlanSettings | PlanBuffers | PlanWAL
-  deriving (Eq, Show)
-
-data MTPlanFormat
-  = PlanJSON | PlanText
-  deriving (Eq, Show)
-
-- | Convert MediaType to a Content-Type HTTP Header
-toContentType :: MediaType -> Header
-toContentType ct = (hContentType, toMime ct <> charset)
-  where
-    charset = case ct of
-      MTOctetStream -> mempty
-      MTOther _     -> mempty
-      _             -> "; charset=utf-8"
-
-- | Convert from MediaType to a ByteString representing the mime type
-toMime :: MediaType -> ByteString
-toMime MTApplicationJSON      = "application/json"
-toMime MTArrayJSONStrip       = "application/vnd.pgrst.array+json;nulls=stripped"
-toMime MTGeoJSON              = "application/geo+json"
-toMime MTTextCSV              = "text/csv"
-toMime MTTextPlain            = "text/plain"
-toMime MTTextXML              = "text/xml"
-toMime MTOpenAPI              = "application/openapi+json"
-toMime (MTSingularJSON True)  = "application/vnd.pgrst.object+json;nulls=stripped"
-toMime (MTSingularJSON False) = "application/vnd.pgrst.object+json"
-toMime MTUrlEncoded           = "application/x-www-form-urlencoded"
-toMime MTOctetStream          = "application/octet-stream"
-toMime MTAny                  = "*/*"
-toMime (MTOther ct)           = ct
-toMime (MTPlan mt fmt opts)   =
-  "application/vnd.pgrst.plan+" <> toMimePlanFormat fmt <>
-  ("; for=\"" <> toMime mt <> "\"") <>
-  (if null opts then mempty else "; options=" <> BS.intercalate "|" (toMimePlanOption <$> opts))
-
-toMimePlanOption :: MTPlanOption -> ByteString
-toMimePlanOption PlanAnalyze  = "analyze"
-toMimePlanOption PlanVerbose  = "verbose"
-toMimePlanOption PlanSettings = "settings"
-toMimePlanOption PlanBuffers  = "buffers"
-toMimePlanOption PlanWAL      = "wal"
-
-toMimePlanFormat :: MTPlanFormat -> ByteString
-toMimePlanFormat PlanJSON = "json"
-toMimePlanFormat PlanText = "text"
-
-- | Convert from ByteString to MediaType.
--
-- >>> decodeMediaType "application/json"
-- MTApplicationJSON
--
-- >>> decodeMediaType "application/vnd.pgrst.plan;"
-- MTPlan MTApplicationJSON PlanText []
--
-- >>> decodeMediaType "application/vnd.pgrst.plan;for=\"application/json\""
-- MTPlan MTApplicationJSON PlanText []
--
-- >>> decodeMediaType "application/vnd.pgrst.plan+json;for=\"text/csv\""
-- MTPlan MTTextCSV PlanJSON []
--
-- >>> decodeMediaType "application/vnd.pgrst.array+json;nulls=stripped"
-- MTArrayJSONStrip
--
-- >>> decodeMediaType "application/vnd.pgrst.array+json"
-- MTApplicationJSON
--
-- >>> decodeMediaType "application/vnd.pgrst.object+json;nulls=stripped"
-- MTSingularJSON True
--
-- >>> decodeMediaType "application/vnd.pgrst.object+json"
-- MTSingularJSON False
-
-decodeMediaType :: BS.ByteString -> MediaType
-decodeMediaType mt =
-  case BS.split (BS.c2w ';') mt of
-    "application/json":_                     -> MTApplicationJSON
-    "application/geo+json":_                 -> MTGeoJSON
-    "text/csv":_                             -> MTTextCSV
-    "text/plain":_                           -> MTTextPlain
-    "text/xml":_                             -> MTTextXML
-    "application/openapi+json":_             -> MTOpenAPI
-    "application/x-www-form-urlencoded":_    -> MTUrlEncoded
-    "application/octet-stream":_             -> MTOctetStream
-    "application/vnd.pgrst.plan":rest        -> getPlan PlanText rest
-    "application/vnd.pgrst.plan+text":rest   -> getPlan PlanText rest
-    "application/vnd.pgrst.plan+json":rest   -> getPlan PlanJSON rest
-    "application/vnd.pgrst.object+json":rest -> checkSingularNullStrip rest
-    "application/vnd.pgrst.object":rest      -> checkSingularNullStrip rest
-    "application/vnd.pgrst.array+json":rest  -> checkArrayNullStrip rest
-    "application/vnd.pgrst.array":rest       -> checkArrayNullStrip rest
-    "*/*":_                                  -> MTAny
-    other:_                                  -> MTOther other
-    _                                        -> MTAny
-  where
-    checkArrayNullStrip ["nulls=stripped"] = MTArrayJSONStrip
-    checkArrayNullStrip  _                 = MTApplicationJSON
-
-    checkSingularNullStrip ["nulls=stripped"] = MTSingularJSON True
-    checkSingularNullStrip  _                 = MTSingularJSON False
-
-    getPlan fmt rest =
-      let
-        opts         = BS.split (BS.c2w '|') $ fromMaybe mempty (BS.stripPrefix "options=" =<< find (BS.isPrefixOf "options=") rest)
-        inOpts str   = str `elem` opts
-        dropAround p = BS.dropWhile p . BS.dropWhileEnd p
-        mtFor        = fromMaybe MTApplicationJSON $ do
-          foundFor    <- find (BS.isPrefixOf "for=") rest
-          strippedFor <- BS.stripPrefix "for=" foundFor
-          pure . decodeMediaType $ dropAround (== BS.c2w '"') strippedFor
-      in
-      MTPlan mtFor fmt $
-        [PlanAnalyze  | inOpts "analyze" ] ++
-        [PlanVerbose  | inOpts "verbose" ] ++
-        [PlanSettings | inOpts "settings"] ++
-        [PlanBuffers  | inOpts "buffers" ] ++
-        [PlanWAL      | inOpts "wal"     ]
@@ -0,0 +1,123 @@
+{-|
+Module      : PostgREST.Middleware
+Description : Sets CORS policy. Also the PostgreSQL GUCs, role, search_path and pre-request function.
+-}
+{-# LANGUAGE BlockArguments  #-}
+{-# LANGUAGE RecordWildCards #-}
+module PostgREST.Middleware
+  ( runPgLocals
+  , optionalRollback
+  ) where
+
+import qualified Data.Aeson                        as JSON
+import qualified Data.ByteString.Lazy.Char8        as LBS
+import qualified Data.HashMap.Strict               as M
+import qualified Data.Text                         as T
+import qualified Data.Text.Encoding                as T
+import qualified Hasql.Decoders                    as HD
+import qualified Hasql.DynamicStatements.Snippet   as SQL hiding (sql)
+import qualified Hasql.DynamicStatements.Statement as SQL
+import qualified Hasql.Transaction                 as SQL
+import qualified Network.Wai                       as Wai
+
+import Control.Arrow ((***))
+
+import Data.Scientific (FPFormat (..), formatScientific, isInteger)
+
+import PostgREST.Config             (AppConfig (..))
+import PostgREST.Config.PgVersion   (PgVersion (..), pgVersion140)
+import PostgREST.Error              (Error, errorResponseFor)
+import PostgREST.GucHeader          (addHeadersIfNotIncluded)
+import PostgREST.Query.SqlFragment  (fromQi, intercalateSnippet,
+                                     unknownEncoder)
+import PostgREST.Request.ApiRequest (ApiRequest (..), Target (..))
+
+import PostgREST.Request.Preferences
+
+import Protolude
+
+-- | Runs local(transaction scoped) GUCs for every request, plus the pre-request function
+runPgLocals :: AppConfig   -> M.HashMap Text JSON.Value ->
+               (ApiRequest -> ExceptT Error SQL.Transaction Wai.Response) ->
+               ApiRequest  -> ByteString -> PgVersion -> ExceptT Error SQL.Transaction Wai.Response
+runPgLocals conf claims app req jsonDbS actualPgVersion = do
+  lift $ SQL.statement mempty $ SQL.dynamicallyParameterized
+    ("select " <> intercalateSnippet ", " (searchPathSql : roleSql ++ claimsSql ++ [methodSql, pathSql] ++ headersSql ++ cookiesSql ++ appSettingsSql ++ specSql))
+    HD.noResult (configDbPreparedStatements conf)
+  lift $ traverse_ SQL.sql preReqSql
+  app req
+  where
+    methodSql = setConfigLocal mempty ("request.method", iMethod req)
+    pathSql = setConfigLocal mempty ("request.path", iPath req)
+    headersSql = if usesLegacyGucs
+                   then setConfigLocal "request.header." <$> iHeaders req
+                   else setConfigLocalJson "request.headers" (iHeaders req)
+    cookiesSql = if usesLegacyGucs
+                   then setConfigLocal "request.cookie." <$> iCookies req
+                   else setConfigLocalJson "request.cookies" (iCookies req)
+    claimsWithRole =
+      let anon = JSON.String . toS $ configDbAnonRole conf in -- role claim defaults to anon if not specified in jwt
+      M.union claims (M.singleton "role" anon)
+    claimsSql = if usesLegacyGucs
+                  then setConfigLocal "request.jwt.claim." <$> [(toUtf8 c, toUtf8 $ unquoted v) | (c,v) <- M.toList claimsWithRole]
+                  else [setConfigLocal mempty ("request.jwt.claims", LBS.toStrict $ JSON.encode claimsWithRole)]
+    roleSql = maybeToList $ (\x -> setConfigLocal mempty ("role", toUtf8 $ unquoted x)) <$> M.lookup "role" claimsWithRole
+    appSettingsSql = setConfigLocal mempty <$> (join bimap toUtf8 <$> configAppSettings conf)
+    searchPathSql =
+      let schemas = T.intercalate ", " (iSchema req : configDbExtraSearchPath conf) in
+      setConfigLocal mempty ("search_path", toUtf8 schemas)
+    preReqSql = (\f -> "select " <> fromQi f <> "();") <$> configDbPreRequest conf
+    specSql = case iTarget req of
+      TargetProc{tpIsRootSpec=True} -> [setConfigLocal mempty ("request.spec", jsonDbS)]
+      _                             -> mempty
+    usesLegacyGucs = configDbUseLegacyGucs conf && actualPgVersion < pgVersion140
+
+    unquoted :: JSON.Value -> Text
+    unquoted (JSON.String t) = t
+    unquoted (JSON.Number n) =
+      toS $ formatScientific Fixed (if isInteger n then Just 0 else Nothing) n
+    unquoted (JSON.Bool b) = show b
+    unquoted v = T.decodeUtf8 . LBS.toStrict $ JSON.encode v
+
+-- | Set a transaction to eventually roll back if requested and set respective
+-- headers on the response.
+optionalRollback
+  :: AppConfig
+  -> ApiRequest
+  -> ExceptT Error SQL.Transaction Wai.Response
+  -> ExceptT Error SQL.Transaction Wai.Response
+optionalRollback AppConfig{..} ApiRequest{..} transaction = do
+  resp <- catchError transaction $ return . errorResponseFor
+  when (shouldRollback || (configDbTxRollbackAll && not shouldCommit)) $ lift do
+    SQL.sql "SET CONSTRAINTS ALL IMMEDIATE"
+    SQL.condemn
+  return $ Wai.mapResponseHeaders preferenceApplied resp
+  where
+    shouldCommit =
+      configDbTxAllowOverride && iPreferTransaction == Just Commit
+    shouldRollback =
+      configDbTxAllowOverride && iPreferTransaction == Just Rollback
+    preferenceApplied
+      | shouldCommit =
+          addHeadersIfNotIncluded
+            [toAppliedHeader Commit]
+      | shouldRollback =
+          addHeadersIfNotIncluded
+            [toAppliedHeader Rollback]
+      | otherwise =
+          identity
+
+-- | Do a pg set_config(setting, value, true) call. This is equivalent to a SET LOCAL.
+setConfigLocal :: ByteString -> (ByteString, ByteString) -> SQL.Snippet
+setConfigLocal prefix (k, v) =
+  "set_config(" <> unknownEncoder (prefix <> k) <> ", " <> unknownEncoder v <> ", true)"
+
+-- | Starting from PostgreSQL v14, some characters are not allowed for config names (mostly affecting headers with "-").
+-- | A JSON format string is used to avoid this problem. See https://github.com/PostgREST/postgrest/issues/1857
+setConfigLocalJson :: ByteString -> [(ByteString, ByteString)] -> [SQL.Snippet]
+setConfigLocalJson prefix keyVals = [setConfigLocal mempty (prefix, gucJsonVal keyVals)]
+  where
+    gucJsonVal :: [(ByteString, ByteString)] -> ByteString
+    gucJsonVal = LBS.toStrict . JSON.encode . M.fromList . arrayByteStringToText
+    arrayByteStringToText :: [(ByteString, ByteString)] -> [(Text,Text)]
+    arrayByteStringToText keyVal = (T.decodeUtf8 *** T.decodeUtf8) <$> keyVal
@@ -3,15 +3,17 @@ Module      : PostgREST.OpenAPI
 Description : Generates the OpenAPI output
 -}
 {-# LANGUAGE LambdaCase      #-}
+{-# LANGUAGE NamedFieldPuns  #-}
 {-# LANGUAGE RecordWildCards #-}
-module PostgREST.Response.OpenAPI (encode) where
+module PostgREST.OpenAPI (encode) where

 import qualified Data.Aeson            as JSON
 import qualified Data.ByteString.Char8 as BS
 import qualified Data.ByteString.Lazy  as LBS
-import qualified Data.HashMap.Strict   as HM
+import qualified Data.HashMap.Strict   as M
 import qualified Data.HashSet.InsOrd   as Set
 import qualified Data.Text             as T
+import qualified Data.Text.Encoding    as T

 import Control.Arrow              ((&&&))
 import Data.HashMap.Strict.InsOrd (InsOrdHashMap, fromList)
@@ -25,34 +27,32 @@ import Data.Swagger

 import PostgREST.Config                   (AppConfig (..), Proxy (..),
                                           isMalformedProxyUri, toURI)
-import PostgREST.SchemaCache              (SchemaCache (..))
-import PostgREST.SchemaCache.Identifiers  (QualifiedIdentifier (..))
-import PostgREST.SchemaCache.Relationship (Cardinality (..),
-                                           Relationship (..),
-                                           RelationshipsMap)
-import PostgREST.SchemaCache.Routine      (Routine (..),
-                                           RoutineParam (..))
-import PostgREST.SchemaCache.Table        (Column (..), Table (..),
-                                           TablesMap,
-                                           tableColumnsList)
+import PostgREST.DbStructure              (DbStructure (..),
+                                           tableCols, tablePKCols)
+import PostgREST.DbStructure.Proc         (ProcDescription (..),
+                                           ProcParam (..))
+import PostgREST.DbStructure.Relationship (Cardinality (..),
+                                           PrimaryKey (..),
+                                           Relationship (..))
+import PostgREST.DbStructure.Table        (Column (..), Table (..))
+import PostgREST.Version                  (docsVersion, prettyVersion)

-import PostgREST.MediaType
+import PostgREST.ContentType

 import Protolude hiding (Proxy, get)

-encode :: (Text, Text) -> AppConfig -> SchemaCache -> TablesMap -> HM.HashMap k [Routine] -> Maybe Text -> LBS.ByteString
-encode versions conf sCache tables procs schemaDescription =
+encode :: AppConfig -> DbStructure -> [Table] -> M.HashMap k [ProcDescription] -> Maybe Text -> LBS.ByteString
+encode conf dbStructure tables procs schemaDescription =
  JSON.encode $
    postgrestSpec
-      versions
-      (dbRelationships sCache)
-      (concat $ HM.elems procs)
-      (snd <$> HM.toList tables)
+      (dbRelationships dbStructure)
+      (concat $ M.elems procs)
+      (openApiTableInfo dbStructure <$> tables)
      (proxyUri conf)
      schemaDescription
-      (configOpenApiSecurityActive conf)
+      (dbPrimaryKeys dbStructure)

-makeMimeList :: [MediaType] -> MimeList
+makeMimeList :: [ContentType] -> MimeList
 makeMimeList cs = MimeList $ fmap (fromString . BS.unpack . toMime) cs

 toSwaggerType :: Text -> Maybe (SwaggerType t)
@@ -66,22 +66,10 @@ toSwaggerType "bigint"            = Just SwaggerInteger
 toSwaggerType "numeric"           = Just SwaggerNumber
 toSwaggerType "real"              = Just SwaggerNumber
 toSwaggerType "double precision"  = Just SwaggerNumber
+toSwaggerType "ARRAY"             = Just SwaggerArray
 toSwaggerType "json"              = Nothing
 toSwaggerType "jsonb"             = Nothing
-toSwaggerType colType             = case T.takeEnd 2 colType of
-  "[]" -> Just SwaggerArray
-  _    -> Just SwaggerString
-
-typeFromArray :: Text -> Text
-typeFromArray = T.dropEnd 2
-
-toSwaggerTypeFromArray :: Text -> Maybe (SwaggerType t)
-toSwaggerTypeFromArray arrType = toSwaggerType $ typeFromArray arrType
-
-makePropertyItems :: Text -> Maybe (Referenced Schema)
-makePropertyItems arrType = case toSwaggerType arrType of
-  Just SwaggerArray -> Just $ Inline (mempty & type_ .~ toSwaggerTypeFromArray arrType)
-  _                 -> Nothing
+toSwaggerType _                   = Just SwaggerString

 parseDefault :: Text -> Text -> Text
 parseDefault colType colDefault =
@@ -93,37 +81,34 @@ parseDefault colType colDefault =
  where
    wrapInQuotations text = "\"" <> text <> "\""

-makeTableDef :: RelationshipsMap -> Table -> (Text, Schema)
-makeTableDef rels t =
+makeTableDef :: [Relationship] -> [PrimaryKey] -> (Table, [Column], [Text]) -> (Text, Schema)
+makeTableDef rels pks (t, cs, _) =
  let tn = tableName t in
      (tn, (mempty :: Schema)
        & description .~ tableDescription t
        & type_ ?~ SwaggerObject
-        & properties .~ fromList (makeProperty t rels <$> tableColumnsList t)
-        & required .~ fmap colName (filter (not . colNullable) $ tableColumnsList t))
+        & properties .~ fromList (fmap (makeProperty rels pks) cs)
+        & required .~ fmap colName (filter (not . colNullable) cs))

-makeProperty :: Table -> RelationshipsMap -> Column -> (Text, Referenced Schema)
-makeProperty tbl rels col = (colName col, Inline s)
+makeProperty :: [Relationship] -> [PrimaryKey] -> Column -> (Text, Referenced Schema)
+makeProperty rels pks c = (colName c, Inline s)
  where
-    e = if null $ colEnum col then Nothing else JSON.decode $ JSON.encode $ colEnum col
+    e = if null $ colEnum c then Nothing else JSON.decode $ JSON.encode $ colEnum c
    fk :: Maybe Text
    fk =
      let
-        searchedRels = fromMaybe mempty $ HM.lookup (QualifiedIdentifier (tableSchema tbl) (tableName tbl), tableSchema tbl) rels
-        -- Sorts the relationship list to get tables first
-        relsSortedByIsView = sortOn relFTableIsView [ r | r@Relationship{} <- searchedRels]
        -- Finds the relationship that has a single column foreign key
        rel = find (\case
-          Relationship{relCardinality=(M2O _ relColumns)} -> [colName col] == (fst <$> relColumns)
-          _                                               -> False
-          ) relsSortedByIsView
-        fCol = (headMay . (\r -> snd <$> relColumns (relCardinality r)) =<< rel)
-        fTbl = qiName . relForeignTable <$> rel
+          Relationship{relColumns, relCardinality=M2O _} -> [c] == relColumns
+          _                                                 -> False
+          ) rels
+        fCol = colName <$> (headMay . relForeignColumns =<< rel)
+        fTbl = tableName . relForeignTable <$> rel
        fTblCol = (,) <$> fTbl <*> fCol
      in
        (\(a, b) -> T.intercalate "" ["This is a Foreign Key to `", a, ".", b, "`.<fk table='", a, "' column='", b, "'/>"]) <$> fTblCol
    pk :: Bool
-    pk = colName col `elem` tablePKCols tbl
+    pk = any (\p -> pkTable p == colTable c && pkName p == colName c) pks
    n = catMaybes
      [ Just "Note:"
      , if pk then Just "This is a Primary Key.<pk/>" else Nothing
@@ -131,20 +116,19 @@ makeProperty tbl rels col = (colName col, Inline s)
      ]
    d =
      if length n > 1 then
-        Just $ T.append (maybe "" (`T.append` "\n\n") $ colDescription col) (T.intercalate "\n" n)
+        Just $ T.append (maybe "" (`T.append` "\n\n") $ colDescription c) (T.intercalate "\n" n)
      else
-        colDescription col
+        colDescription c
    s =
      (mempty :: Schema)
-        & default_ .~ (JSON.decode . toUtf8Lazy . parseDefault (colType col) =<< colDefault col)
+        & default_ .~ (JSON.decode . toUtf8Lazy . parseDefault (colType c) =<< colDefault c)
        & description .~ d
        & enum_ .~ e
-        & format ?~ colType col
-        & maxLength .~ (fromIntegral <$> colMaxLen col)
-        & type_ .~ toSwaggerType (colType col)
-        & items .~ (SwaggerItemsObject <$> makePropertyItems (colType col))
+        & format ?~ colType c
+        & maxLength .~ (fromIntegral <$> colMaxLen c)
+        & type_ .~ toSwaggerType (colType c)

-makeProcSchema :: Routine -> Schema
+makeProcSchema :: ProcDescription -> Schema
 makeProcSchema pd =
  (mempty :: Schema)
  & description .~ pdDescription pd
@@ -152,12 +136,11 @@ makeProcSchema pd =
  & properties .~ fromList (fmap makeProcProperty (pdParams pd))
  & required .~ fmap ppName (filter ppReq (pdParams pd))

-makeProcProperty :: RoutineParam -> (Text, Referenced Schema)
-makeProcProperty (RoutineParam n t _ _ _) = (n, Inline s)
+makeProcProperty :: ProcParam -> (Text, Referenced Schema)
+makeProcProperty (ProcParam n t _ _) = (n, Inline s)
  where
    s = (mempty :: Schema)
          & type_ .~ toSwaggerType t
-          & items .~ (SwaggerItemsObject <$> makePropertyItems t)
          & format ?~ t

 makePreferParam :: [Text] -> Param
@@ -169,47 +152,10 @@ makePreferParam ts =
  & schema .~ ParamOther ((mempty :: ParamOtherSchema)
    & in_ .~ ParamHeader
    & type_ ?~ SwaggerString
-    & enum_ .~ JSON.decode (JSON.encode $ foldl (<>) [] (val <$> ts)))
-  where
-    val :: Text -> [Text]
-    val = \case
-      "count"      -> ["count=none"]
-      "params"     -> ["params=single-object"]
-      "return"     -> ["return=representation", "return=minimal", "return=none"]
-      "resolution" -> ["resolution=ignore-duplicates", "resolution=merge-duplicates"]
-      _            -> []
+    & enum_ .~ JSON.decode (JSON.encode ts))

-makeProcGetParam :: RoutineParam -> Referenced Param
-makeProcGetParam (RoutineParam n t _ r v) =
-  Inline $ (mempty :: Param)
-    & name .~ n
-    & required ?~ r
-    & schema .~ ParamOther fullSchema
-  where
-    fullSchema = if v then schemaMulti else schemaNotMulti
-    baseSchema = (mempty :: ParamOtherSchema)
-      & in_ .~ ParamQuery
-    schemaNotMulti = baseSchema
-      & format ?~ t
-      & type_ ?~ toParamType (toSwaggerType t)
-    schemaMulti = baseSchema
-      & type_ ?~ fromMaybe SwaggerString (toSwaggerType t)
-      & items ?~ SwaggerItemsPrimitive (Just CollectionMulti)
-        ((mempty :: ParamSchema x)
-          & type_ .~ toSwaggerTypeFromArray t
-          & format ?~ typeFromArray t)
-    toParamType paramType = case paramType of
-      -- Array uses {} in query params
-      Just SwaggerArray -> SwaggerString
-      -- Type must be specified in query params
-      Nothing           -> SwaggerString
-      _                 -> fromJust paramType
-
-makeProcGetParams :: [RoutineParam] -> [Referenced Param]
-makeProcGetParams = fmap makeProcGetParam
-
-makeProcPostParams :: Routine -> [Referenced Param]
-makeProcPostParams pd =
+makeProcParam :: ProcDescription -> [Referenced Param]
+makeProcParam pd =
  [ Inline $ (mempty :: Param)
    & name     .~ "args"
    & required ?~ True
@@ -217,13 +163,11 @@ makeProcPostParams pd =
  , Ref $ Reference "preferParams"
  ]

-makeParamDefs :: [Table] -> [(Text, Param)]
+makeParamDefs :: [(Table, [Column], [Text])] -> [(Text, Param)]
 makeParamDefs ti =
-  -- TODO: create Prefer for each method (GET, PATCH, etc.)
-  [ ("preferParams", makePreferParam ["params"])
-  , ("preferReturn", makePreferParam ["return"])
-  , ("preferCount", makePreferParam ["count"])
-  , ("preferPost", makePreferParam ["return", "resolution"])
+  [ ("preferParams", makePreferParam ["params=single-object"])
+  , ("preferReturn", makePreferParam ["return=representation", "return=minimal", "return=none"])
+  , ("preferCount", makePreferParam ["count=none"])
  , ("select", (mempty :: Param)
      & name        .~ "select"
      & description ?~ "Filtering Columns"
@@ -275,8 +219,8 @@ makeParamDefs ti =
        & in_ .~ ParamQuery
        & type_ ?~ SwaggerString))
  ]
-  <> concat [ makeObjectBody (tableName t) : makeRowFilters (tableName t) (tableColumnsList t)
-            | t <- ti
+  <> concat [ makeObjectBody (tableName t) : makeRowFilters (tableName t) cs
+            | (t, cs, _) <- ti
            ]

 makeObjectBody :: Text -> (Text, Param)
@@ -301,8 +245,8 @@ makeRowFilter tn c =
 makeRowFilters :: Text -> [Column] -> [(Text, Param)]
 makeRowFilters tn = fmap (makeRowFilter tn)

-makePathItem :: Table -> (FilePath, PathItem)
-makePathItem t = ("/" ++ T.unpack tn, p $ tableInsertable t || tableUpdatable t || tableDeletable t)
+makePathItem :: (Table, [Column], [Text]) -> (FilePath, PathItem)
+makePathItem (t, cs, _) = ("/" ++ T.unpack tn, p $ tableInsertable t || tableUpdatable t || tableDeletable t)
  where
    -- Use first line of table description as summary; rest as description (if present)
    -- We strip leading newlines from description so that users can include a blank line between summary and description
@@ -323,7 +267,7 @@ makePathItem t = ("/" ++ T.unpack tn, p $ tableInsertable t || tableUpdatable t
        )
      )
    postOp = tOp
-      & parameters .~ fmap ref ["body." <> tn, "select", "preferPost"]
+      & parameters .~ fmap ref ["body." <> tn, "select", "preferReturn"]
      & at 201 ?~ "Created"
    patchOp = tOp
      & parameters .~ fmap ref (rs <> ["body." <> tn, "preferReturn"])
@@ -336,29 +280,24 @@ makePathItem t = ("/" ++ T.unpack tn, p $ tableInsertable t || tableUpdatable t
    p False = pr
    p True  = pw
    tn = tableName t
-    rs = [ T.intercalate "." ["rowFilter", tn, colName c ] | c <- tableColumnsList t ]
+    rs = [ T.intercalate "." ["rowFilter", tn, colName c ] | c <- cs ]
    ref = Ref . Reference

-makeProcPathItem :: Routine -> (FilePath, PathItem)
+makeProcPathItem :: ProcDescription -> (FilePath, PathItem)
 makeProcPathItem pd = ("/rpc/" ++ toS (pdName pd), pe)
  where
    -- Use first line of proc description as summary; rest as description (if present)
    -- We strip leading newlines from description so that users can include a blank line between summary and description
    (pSum, pDesc) = fmap fst &&& fmap (T.dropWhile (=='\n') . snd) $
                    T.breakOn "\n" <$> pdDescription pd
-    procOp = (mempty :: Operation)
+    postOp = (mempty :: Operation)
      & summary .~ pSum
      & description .~ mfilter (/="") pDesc
+      & parameters .~ makeProcParam pd
      & tags .~ Set.fromList ["(rpc) " <> pdName pd]
-      & produces ?~ makeMimeList [MTApplicationJSON, MTSingularJSON True, MTSingularJSON False]
+      & produces ?~ makeMimeList [CTApplicationJSON, CTSingularJSON]
      & at 200 ?~ "OK"
-    getOp = procOp
-      & parameters .~ makeProcGetParams (pdParams pd)
-    postOp = procOp
-      & parameters .~ makeProcPostParams pd
-    pe = (mempty :: PathItem)
-      & get ?~ getOp
-      & post ?~ postOp
+    pe = (mempty :: PathItem) & post ?~ postOp

 makeRootPathItem :: (FilePath, PathItem)
 makeRootPathItem = ("/", p)
@@ -366,23 +305,15 @@ makeRootPathItem = ("/", p)
    getOp = (mempty :: Operation)
      & tags .~ Set.fromList ["Introspection"]
      & summary ?~ "OpenAPI description (this document)"
-      & produces ?~ makeMimeList [MTOpenAPI, MTApplicationJSON]
+      & produces ?~ makeMimeList [CTOpenAPI, CTApplicationJSON]
      & at 200 ?~ "OK"
    pr = (mempty :: PathItem) & get ?~ getOp
    p = pr

-makePathItems :: [Routine] -> [Table] -> InsOrdHashMap FilePath PathItem
+makePathItems :: [ProcDescription] -> [(Table, [Column], [Text])] -> InsOrdHashMap FilePath PathItem
 makePathItems pds ti = fromList $ makeRootPathItem :
  fmap makePathItem ti ++ fmap makeProcPathItem pds

-makeSecurityDefinitions :: Text -> Bool -> SecurityDefinitions
-makeSecurityDefinitions secName allow
-  | allow = SecurityDefinitions (fromList [(secName, SecurityScheme secSchType secSchDescription)])
-  | otherwise    = mempty
-  where
-    secSchType = SecuritySchemeApiKey (ApiKeyParams "Authorization" ApiKeyHeader)
-    secSchDescription = Just "Add the token prepending \"Bearer \" (without quotes) to it"
-
 escapeHostName :: Text -> Text
 escapeHostName "*"  = "0.0.0.0"
 escapeHostName "*4" = "0.0.0.0"
@@ -391,31 +322,27 @@ escapeHostName "*6" = "0.0.0.0"
 escapeHostName "!6" = "0.0.0.0"
 escapeHostName h    = h

-postgrestSpec :: (Text, Text) -> RelationshipsMap -> [Routine] -> [Table] -> (Text, Text, Integer, Text) -> Maybe Text -> Bool -> Swagger
-postgrestSpec (prettyVersion, docsVersion) rels pds ti (s, h, p, b) sd allowSecurityDef = (mempty :: Swagger)
+postgrestSpec :: [Relationship] -> [ProcDescription] -> [(Table, [Column], [Text])] -> (Text, Text, Integer, Text) -> Maybe Text -> [PrimaryKey] -> Swagger
+postgrestSpec rels pds ti (s, h, p, b) sd pks = (mempty :: Swagger)
  & basePath ?~ T.unpack b
  & schemes ?~ [s']
  & info .~ ((mempty :: Info)
-      & version .~ prettyVersion
-      & title .~ fromMaybe "PostgREST API" dTitle
-      & description ?~ fromMaybe "This is a dynamic API generated by PostgREST" dDesc)
+      & version .~ T.decodeUtf8 prettyVersion
+      & title .~ "PostgREST API"
+      & description ?~ d)
  & externalDocs ?~ ((mempty :: ExternalDocs)
    & description ?~ "PostgREST Documentation"
    & url .~ URL ("https://postgrest.org/en/" <> docsVersion <> "/api.html"))
  & host .~ h'
-  & definitions .~ fromList (makeTableDef rels <$> ti)
+  & definitions .~ fromList (makeTableDef rels pks <$> ti)
  & parameters .~ fromList (makeParamDefs ti)
  & paths .~ makePathItems pds ti
-  & produces .~ makeMimeList [MTApplicationJSON, MTSingularJSON True, MTSingularJSON False, MTTextCSV]
-  & consumes .~ makeMimeList [MTApplicationJSON, MTSingularJSON True, MTSingularJSON False, MTTextCSV]
-  & securityDefinitions .~ makeSecurityDefinitions securityDefName allowSecurityDef
-  & security .~ [SecurityRequirement (fromList [(securityDefName, [])]) | allowSecurityDef]
+  & produces .~ makeMimeList [CTApplicationJSON, CTSingularJSON, CTTextCSV]
+  & consumes .~ makeMimeList [CTApplicationJSON, CTSingularJSON, CTTextCSV]
    where
      s' = if s == "http" then Http else Https
      h' = Just $ Host (T.unpack $ escapeHostName h) (Just (fromInteger p))
-      securityDefName = "JWT"
-      (dTitle, dDesc) = fmap fst &&& fmap (T.dropWhile (=='\n') . snd) $
-                    T.breakOn "\n" <$> sd
+      d = fromMaybe "This is a dynamic API generated by PostgREST" sd

 pickProxy :: Maybe Text -> Maybe Proxy
 pickProxy proxy
@@ -453,3 +380,10 @@ proxyUri AppConfig{..} =
      (proxyScheme, proxyHost, proxyPort, proxyPath)
    Nothing ->
      ("http", configServerHost, toInteger configServerPort, "/")
+
+openApiTableInfo :: DbStructure -> Table -> (Table, [Column], [Text])
+openApiTableInfo dbStructure table =
+  ( table
+  , tableCols dbStructure (tableSchema table) (tableName table)
+  , tablePKCols dbStructure (tableSchema table) (tableName table)
+  )
@@ -1,872 +0,0 @@
-{-|
-Module      : PostgREST.Plan
-Description : PostgREST Request Planner
-
-This module is in charge of building an intermediate
-representation between the HTTP request and the
-final resulting SQL query.
-
-A query tree is built in case of resource embedding. By inferring the
-relationship between tables, join conditions are added for every embedded
-resource.
-}
-{-# LANGUAGE DuplicateRecordFields #-}
-{-# LANGUAGE LambdaCase            #-}
-{-# LANGUAGE NamedFieldPuns        #-}
-{-# LANGUAGE RecordWildCards       #-}
-
-module PostgREST.Plan
-  ( wrappedReadPlan
-  , mutateReadPlan
-  , callReadPlan
-  , WrappedReadPlan(..)
-  , MutateReadPlan(..)
-  , CallReadPlan(..)
-  , inspectPlanTxMode
-  ) where
-
-import qualified Data.ByteString.Lazy          as LBS
-import qualified Data.HashMap.Strict           as HM
-import qualified Data.HashMap.Strict.InsOrd    as HMI
-import qualified Data.List                     as L
-import qualified Data.Set                      as S
-import qualified PostgREST.SchemaCache.Routine as Routine
-
-import Data.Either.Combinators (mapLeft, mapRight)
-import Data.List               (delete)
-import Data.Tree               (Tree (..))
-
-import PostgREST.ApiRequest                  (Action (..),
-                                              ApiRequest (..),
-                                              InvokeMethod (..),
-                                              Mutation (..),
-                                              Payload (..))
-import PostgREST.Config                      (AppConfig (..))
-import PostgREST.Error                       (Error (..))
-import PostgREST.MediaType                   (MediaType (..))
-import PostgREST.Query.SqlFragment           (sourceCTEName)
-import PostgREST.RangeQuery                  (NonnegRange, allRange,
-                                              convertToLimitZeroRange,
-                                              restrictRange)
-import PostgREST.SchemaCache                 (SchemaCache (..))
-import PostgREST.SchemaCache.Identifiers     (FieldName,
-                                              QualifiedIdentifier (..),
-                                              Schema)
-import PostgREST.SchemaCache.Relationship    (Cardinality (..),
-                                              Junction (..),
-                                              Relationship (..),
-                                              RelationshipsMap,
-                                              relIsToOne)
-import PostgREST.SchemaCache.Representations (DataRepresentation (..),
-                                              RepresentationsMap)
-import PostgREST.SchemaCache.Routine         (ResultAggregate (..),
-                                              Routine (..),
-                                              RoutineMap,
-                                              RoutineParam (..),
-                                              funcReturnsCompositeAlias,
-                                              funcReturnsScalar,
-                                              funcReturnsSetOfScalar)
-import PostgREST.SchemaCache.Table           (Column (..), Table (..),
-                                              TablesMap,
-                                              tableColumnsList,
-                                              tablePKCols)
-
-import PostgREST.ApiRequest.Preferences
-import PostgREST.ApiRequest.Types
-import PostgREST.Plan.CallPlan
-import PostgREST.Plan.MutatePlan
-import PostgREST.Plan.ReadPlan          as ReadPlan
-import PostgREST.Plan.Types
-
-import qualified Hasql.Transaction.Sessions       as SQL
-import qualified PostgREST.ApiRequest.QueryParams as QueryParams
-
-import Protolude hiding (from)
-
-- $setup
-- Setup for doctests
-- >>> import Data.Ranged.Ranges (fullRange)
-
-data WrappedReadPlan = WrappedReadPlan {
-  wrReadPlan :: ReadPlanTree
-, wrTxMode   :: SQL.Mode
-, wrResAgg   :: ResultAggregate
-}
-
-data MutateReadPlan = MutateReadPlan {
-  mrReadPlan   :: ReadPlanTree
-, mrMutatePlan :: MutatePlan
-, mrTxMode     :: SQL.Mode
-, mrResAgg     :: ResultAggregate
-}
-
-data CallReadPlan = CallReadPlan {
-  crReadPlan :: ReadPlanTree
-, crCallPlan :: CallPlan
-, crTxMode   :: SQL.Mode
-, crProc     :: Routine
-, crResAgg   :: ResultAggregate
-}
-
-wrappedReadPlan :: QualifiedIdentifier -> AppConfig -> SchemaCache -> ApiRequest -> Either Error WrappedReadPlan
-wrappedReadPlan  identifier conf sCache apiRequest = do
-  rPlan <- readPlan identifier conf sCache apiRequest
-  binField <- mapLeft ApiRequestError $ binaryField conf (iAcceptMediaType apiRequest) Nothing rPlan
-  return $ WrappedReadPlan rPlan SQL.Read $ mediaToAggregate (iAcceptMediaType apiRequest) binField apiRequest
-
-mutateReadPlan :: Mutation -> ApiRequest -> QualifiedIdentifier -> AppConfig -> SchemaCache -> Either Error MutateReadPlan
-mutateReadPlan  mutation apiRequest identifier conf sCache = do
-  rPlan <- readPlan identifier conf sCache apiRequest
-  binField <- mapLeft ApiRequestError $ binaryField conf (iAcceptMediaType apiRequest) Nothing rPlan
-  mPlan <- mutatePlan mutation identifier apiRequest sCache rPlan
-  return $ MutateReadPlan rPlan mPlan SQL.Write $ mediaToAggregate (iAcceptMediaType apiRequest) binField apiRequest
-
-callReadPlan :: QualifiedIdentifier -> AppConfig -> SchemaCache -> ApiRequest -> InvokeMethod -> Either Error CallReadPlan
-callReadPlan identifier conf sCache apiRequest invMethod = do
-  let paramKeys = case invMethod of
-        InvGet  -> S.fromList $ fst <$> qsParams'
-        InvHead -> S.fromList $ fst <$> qsParams'
-        InvPost -> iColumns apiRequest
-  proc@Function{..} <- mapLeft ApiRequestError $
-    findProc identifier paramKeys (preferParameters == Just SingleObject) (dbRoutines sCache) (iContentMediaType apiRequest) (invMethod == InvPost)
-  let relIdentifier = QualifiedIdentifier pdSchema (fromMaybe pdName $ Routine.funcTableName proc) -- done so a set returning function can embed other relations
-  rPlan <- readPlan relIdentifier conf sCache apiRequest
-  let args = case (invMethod, iContentMediaType apiRequest) of
-        (InvGet, _)             -> jsonRpcParams proc qsParams'
-        (InvHead, _)            -> jsonRpcParams proc qsParams'
-        (InvPost, MTUrlEncoded) -> maybe mempty (jsonRpcParams proc . payArray) $ iPayload apiRequest
-        (InvPost, _)            -> maybe mempty payRaw $ iPayload apiRequest
-      txMode = case (invMethod, pdVolatility) of
-          (InvGet,  _)                 -> SQL.Read
-          (InvHead, _)                 -> SQL.Read
-          (InvPost, Routine.Stable)    -> SQL.Read
-          (InvPost, Routine.Immutable) -> SQL.Read
-          (InvPost, Routine.Volatile)  -> SQL.Write
-      cPlan = callPlan proc apiRequest paramKeys args rPlan
-  binField <- mapLeft ApiRequestError $ binaryField conf (iAcceptMediaType apiRequest) (Just proc) rPlan
-  return $ CallReadPlan rPlan cPlan txMode proc $ mediaToAggregate (iAcceptMediaType apiRequest) binField apiRequest
-  where
-    Preferences{..} = iPreferences apiRequest
-    qsParams' = QueryParams.qsParams (iQueryParams apiRequest)
-
-{-|
-  Search a pg proc by matching name and arguments keys to parameters. Since a function can be overloaded,
-  the name is not enough to find it. An overloaded function can have a different volatility or even a different return type.
-}
-findProc :: QualifiedIdentifier -> S.Set Text -> Bool -> RoutineMap -> MediaType -> Bool -> Either ApiRequestError Routine
-findProc qi argumentsKeys paramsAsSingleObject allProcs contentMediaType isInvPost =
-  case matchProc of
-    ([], [])     -> Left $ NoRpc (qiSchema qi) (qiName qi) (S.toList argumentsKeys) paramsAsSingleObject contentMediaType isInvPost (HM.keys allProcs) lookupProcName
-    -- If there are no functions with named arguments, fallback to the single unnamed argument function
-    ([], [proc]) -> Right proc
-    ([], procs)  -> Left $ AmbiguousRpc (toList procs)
-    -- Matches the functions with named arguments
-    ([proc], _)  -> Right proc
-    (procs, _)   -> Left $ AmbiguousRpc (toList procs)
-  where
-    matchProc = overloadedProcPartition lookupProcName
-    -- First find the proc by name
-    lookupProcName = HM.lookupDefault mempty qi allProcs
-    -- The partition obtained has the form (overloadedProcs,fallbackProcs)
-    -- where fallbackProcs are functions with a single unnamed parameter
-    overloadedProcPartition = foldr select ([],[])
-    select proc ~(ts,fs)
-      | matchesParams proc         = (proc:ts,fs)
-      | hasSingleUnnamedParam proc = (ts,proc:fs)
-      | otherwise                  = (ts,fs)
-    -- If the function is called with post and has a single unnamed parameter
-    -- it can be called depending on content type and the parameter type
-    hasSingleUnnamedParam Function{pdParams=[RoutineParam{ppType}]} = isInvPost && case (contentMediaType, ppType) of
-      (MTApplicationJSON, "json")  -> True
-      (MTApplicationJSON, "jsonb") -> True
-      (MTTextPlain, "text")        -> True
-      (MTTextXML, "xml")           -> True
-      (MTOctetStream, "bytea")     -> True
-      _                            -> False
-    hasSingleUnnamedParam _ = False
-    matchesParams proc =
-      let
-        params = pdParams proc
-        firstType = (ppType <$> headMay params)
-      in
-      -- exceptional case for Prefer: params=single-object
-      if paramsAsSingleObject
-        then length params == 1 && (firstType == Just "json" || firstType == Just "jsonb")
-      -- If the function has no parameters, the arguments keys must be empty as well
-      else if null params
-        then null argumentsKeys && not (isInvPost && contentMediaType `elem` [MTOctetStream, MTTextPlain, MTTextXML])
-      -- A function has optional and required parameters. Optional parameters have a default value and
-      -- don't require arguments for the function to be executed, required parameters must have an argument present.
-      else case L.partition ppReq params of
-      -- If the function only has required parameters, the arguments keys must match those parameters
-        (reqParams, [])        -> argumentsKeys == S.fromList (ppName <$> reqParams)
-      -- If the function only has optional parameters, the arguments keys can match none or any of them(a subset)
-        ([], optParams)        -> argumentsKeys `S.isSubsetOf` S.fromList (ppName <$> optParams)
-      -- If the function has required and optional parameters, the arguments keys have to match the required parameters
-      -- and can match any or none of the default parameters.
-        (reqParams, optParams) -> argumentsKeys `S.difference` S.fromList (ppName <$> optParams) == S.fromList (ppName <$> reqParams)
-
-inspectPlanTxMode :: SQL.Mode
-inspectPlanTxMode = SQL.Read
-
-- | During planning we need to resolve Field -> CoercibleField (finding the context specific target type and map function).
-- | ResolverContext facilitates this without the need to pass around a laundry list of parameters.
-data ResolverContext = ResolverContext
-  { tables          :: TablesMap
-  , representations :: RepresentationsMap
-  , qi              :: QualifiedIdentifier  -- ^ The table we're currently attending; changes as we recurse into joins etc.
-  , outputType      :: Text                 -- ^ The output type for the response payload; e.g. "csv", "json", "binary".
-  }
-
-resolveColumnField :: Column -> CoercibleField
-resolveColumnField col = CoercibleField (colName col) mempty False (colNominalType col) Nothing (colDefault col)
-
-resolveTableFieldName :: Table -> FieldName -> CoercibleField
-resolveTableFieldName table fieldName =
-  fromMaybe (unknownField fieldName []) $ HMI.lookup fieldName (tableColumns table) >>=
-    Just . resolveColumnField
-
-- | Resolve a type within the context based on the given field name and JSON path. Although there are situations where failure to resolve a field is considered an error (see `resolveOrError`), there are also situations where we allow it (RPC calls). If it should be an error and `resolveOrError` doesn't fit, ensure to check the `cfIRType` isn't empty.
-resolveTypeOrUnknown :: ResolverContext -> Field -> CoercibleField
-resolveTypeOrUnknown ResolverContext{..} (fn, jp) =
-  case res of
-    -- types that are already json/jsonb don't need to be converted with `to_jsonb` for using arrow operators `data->attr`
-    -- this prevents indexes not applying https://github.com/PostgREST/postgrest/issues/2594
-    cf@CoercibleField{cfIRType="json"}  -> cf{cfJsonPath=jp, cfToJson=False}
-    cf@CoercibleField{cfIRType="jsonb"} -> cf{cfJsonPath=jp, cfToJson=False}
-    -- other types will get converted `to_jsonb(col)->attr`, even unknown types
-    cf                                  -> cf{cfJsonPath=jp, cfToJson=True}
-  where
-    res = fromMaybe (unknownField fn jp) $ HM.lookup qi tables >>=
-          Just . flip resolveTableFieldName fn
-
-- | Install any pre-defined data representation from source to target to coerce this reference.
--
-- Note that we change the IR type here. This might seem unintuitive. The short of it is that for a CoercibleField without a transformer, input type == output type. A transformer maps from a -> b, so by definition the input type will be a and the output type b after. And cfIRType is the *input* type.
--
-- It might feel odd that once a transformer is added we 'forget' the target type (because now a /= b). You might also note there's no obvious way to stack transforms (even if there was a stack, you erased what type you're working with so it's awkward). Alas as satisfying as it would be to engineer a layered mapping system with full type information, we just don't need it.
-withTransformer :: ResolverContext -> Text -> Text -> CoercibleField -> CoercibleField
-withTransformer ResolverContext{representations} sourceType targetType field =
-  fromMaybe field $ HM.lookup (sourceType, targetType) representations >>=
-    (\fieldRepresentation -> Just field{cfIRType=sourceType, cfTransform=Just (drFunction fieldRepresentation)})
-
-- | Map the intermediate representation type to the output type, if available.
-withOutputFormat :: ResolverContext -> CoercibleField -> CoercibleField
-withOutputFormat ctx@ResolverContext{outputType} field@CoercibleField{cfIRType} = withTransformer ctx cfIRType outputType field
-
-- | Map text into the intermediate representation type, if available.
-withTextParse :: ResolverContext -> CoercibleField -> CoercibleField
-withTextParse ctx field@CoercibleField{cfIRType} = withTransformer ctx "text" cfIRType field
-
-- | Map json into the intermediate representation type, if available.
-withJsonParse :: ResolverContext -> CoercibleField -> CoercibleField
-withJsonParse ctx field@CoercibleField{cfIRType} = withTransformer ctx "json" cfIRType field
-
-- | Map the intermediate representation type to the output type defined by the resolver context (normally json), if available.
-resolveOutputField :: ResolverContext -> Field -> CoercibleField
-resolveOutputField ctx field = withOutputFormat ctx $ resolveTypeOrUnknown ctx field
-
-- | Map the query string format of a value (text) into the intermediate representation type, if available.
-resolveQueryInputField :: ResolverContext -> Field -> CoercibleField
-resolveQueryInputField ctx field = withTextParse ctx $ resolveTypeOrUnknown ctx field
-
-- | Builds the ReadPlan tree on a number of stages.
-- | Adds filters, order, limits on its respective nodes.
-- | Adds joins conditions obtained from resource embedding.
-readPlan :: QualifiedIdentifier -> AppConfig -> SchemaCache -> ApiRequest -> Either Error ReadPlanTree
-readPlan qi@QualifiedIdentifier{..} AppConfig{configDbMaxRows} SchemaCache{dbTables, dbRelationships, dbRepresentations} apiRequest  =
-  let
-    -- JSON output format hardcoded for now. In the future we might want to support other output mappings such as CSV.
-    ctx = ResolverContext dbTables dbRepresentations qi "json"
-  in
-    mapLeft ApiRequestError $
-    treeRestrictRange configDbMaxRows (iAction apiRequest) =<<
-    addNullEmbedFilters =<<
-    validateSpreadEmbeds =<<
-    addRelatedOrders =<<
-    addDataRepresentationAliases =<<
-    expandStarsForDataRepresentations ctx =<<
-    addRels qiSchema (iAction apiRequest) dbRelationships Nothing =<<
-    addLogicTrees ctx apiRequest =<<
-    addRanges apiRequest =<<
-    addOrders ctx apiRequest =<<
-    addFilters ctx apiRequest (initReadRequest ctx $ QueryParams.qsSelect $ iQueryParams apiRequest)
-
-- Build the initial read plan tree
-initReadRequest :: ResolverContext -> [Tree SelectItem] -> ReadPlanTree
-initReadRequest ctx@ResolverContext{qi=QualifiedIdentifier{..}} =
-  foldr (treeEntry rootDepth) $ Node defReadPlan{from=qi ctx, relName=qiName, depth=rootDepth} []
-  where
-    rootDepth = 0
-    defReadPlan = ReadPlan [] (QualifiedIdentifier mempty mempty) Nothing [] [] allRange mempty Nothing [] Nothing mempty Nothing Nothing False rootDepth
-    treeEntry :: Depth -> Tree SelectItem -> ReadPlanTree -> ReadPlanTree
-    treeEntry depth (Node si fldForest) (Node q rForest) =
-      let nxtDepth = succ depth in
-      case si of
-        SelectRelation{..} ->
-          Node q $
-            foldr (treeEntry nxtDepth)
-            (Node defReadPlan{from=QualifiedIdentifier qiSchema selRelation, relName=selRelation, relAlias=selAlias, relHint=selHint, relJoinType=selJoinType, depth=nxtDepth} [])
-            fldForest:rForest
-        SpreadRelation{..} ->
-          Node q $
-            foldr (treeEntry nxtDepth)
-            (Node defReadPlan{from=QualifiedIdentifier qiSchema selRelation, relName=selRelation, relHint=selHint, relJoinType=selJoinType, depth=nxtDepth, relIsSpread=True} [])
-            fldForest:rForest
-        SelectField{..} ->
-          Node q{select=(resolveOutputField ctx{qi=from q} selField, selCast, selAlias):select q} rForest
-
-- | Preserve the original field name if data representation is used to coerce the value.
-addDataRepresentationAliases :: ReadPlanTree -> Either ApiRequestError ReadPlanTree
-addDataRepresentationAliases rPlanTree = Right $ fmap (\rPlan@ReadPlan{select=sel} -> rPlan{select=map aliasSelectItem sel}) rPlanTree
-  where
-    aliasSelectItem :: (CoercibleField, Maybe Cast, Maybe Alias) -> (CoercibleField, Maybe Cast, Maybe Alias)
-    -- If there already is an alias, don't overwrite it.
-    aliasSelectItem (fld@(CoercibleField{cfName=fieldName, cfTransform=(Just _)}), Nothing, Nothing) = (fld, Nothing, Just fieldName)
-    aliasSelectItem fld = fld
-
-knownColumnsInContext :: ResolverContext -> [Column]
-knownColumnsInContext ResolverContext{..} =
-  fromMaybe [] $ HM.lookup qi tables >>=
-  Just . tableColumnsList
-
-- | Expand "select *" into explicit field names of the table, if necessary to apply data representations.
-expandStarsForDataRepresentations :: ResolverContext -> ReadPlanTree -> Either ApiRequestError ReadPlanTree
-expandStarsForDataRepresentations ctx@ResolverContext{qi} rPlanTree = Right $ fmap expandStars rPlanTree
-  where
-    expandStars :: ReadPlan -> ReadPlan
-    -- When the schema is "" and the table is the source CTE, we assume the true source table is given in the from
-    -- alias and belongs to the request schema. See the bit in `addRels` with `newFrom = ...`.
-    expandStars rPlan@ReadPlan{from=(QualifiedIdentifier "" "pgrst_source"), fromAlias=(Just tblAlias)} =
-      expandStarsForTable ctx{qi=qi{qiName=tblAlias}} rPlan
-    expandStars rPlan@ReadPlan{from=fromTable} =
-      expandStarsForTable ctx{qi=fromTable} rPlan
-
-expandStarsForTable :: ResolverContext -> ReadPlan -> ReadPlan
-expandStarsForTable ctx@ResolverContext{representations, outputType} rplan@ReadPlan{select=selectItems} =
-  -- If we have a '*' select AND the target table has at least one data representation, expand.
-  if ("*" `elem` map (\(field, _, _) -> cfName field) selectItems) && any hasOutputRep knownColumns
-    then rplan{select=concatMap (expandStarSelectItem knownColumns) selectItems}
-    else rplan
-  where
-    knownColumns = knownColumnsInContext ctx
-
-    hasOutputRep :: Column -> Bool
-    hasOutputRep col = HM.member (colNominalType col, outputType) representations
-
-    expandStarSelectItem :: [Column] -> (CoercibleField, Maybe Cast, Maybe Alias) -> [(CoercibleField, Maybe Cast, Maybe Alias)]
-    expandStarSelectItem columns (CoercibleField{cfName="*", cfJsonPath=[]}, b, c) = map (\col -> (withOutputFormat ctx $ resolveColumnField col, b, c)) columns
-    expandStarSelectItem _ selectItem = [selectItem]
-
-- | Enforces the `max-rows` config on the result
-treeRestrictRange :: Maybe Integer -> Action -> ReadPlanTree -> Either ApiRequestError ReadPlanTree
-treeRestrictRange _ (ActionMutate _) request = Right request
-treeRestrictRange maxRows _ request = pure $ nodeRestrictRange maxRows <$> request
-  where
-    nodeRestrictRange :: Maybe Integer -> ReadPlan -> ReadPlan
-    nodeRestrictRange m q@ReadPlan{range_=r} = q{range_= convertToLimitZeroRange r (restrictRange m r) }
-
-- add relationships to the nodes of the tree by traversing the forest while keeping track of the parentNode(https://stackoverflow.com/questions/22721064/get-the-parent-of-a-node-in-data-tree-haskell#comment34627048_22721064)
-- also adds aliasing
-addRels :: Schema -> Action -> RelationshipsMap -> Maybe ReadPlanTree -> ReadPlanTree -> Either ApiRequestError ReadPlanTree
-addRels schema action allRels parentNode (Node rPlan@ReadPlan{relName,relHint,relAlias,depth} forest) =
-  case parentNode of
-    Just (Node ReadPlan{from=parentNodeQi, fromAlias=parentAlias} _) ->
-      let
-        newReadPlan = (\r ->
-          let newAlias = Just (qiName (relForeignTable r) <> "_" <> show depth)
-              aggAlias = qiName (relTable r) <> "_" <> fromMaybe relName relAlias <> "_" <> show depth in
-          case r of
-            Relationship{relCardinality=M2M _} -> -- m2m does internal implicit joins that don't need aliasing
-              rPlan{from=relForeignTable r, relToParent=Just r, relAggAlias=aggAlias, relJoinConds=getJoinConditions Nothing parentAlias r}
-            ComputedRelationship{} ->
-              rPlan{from=relForeignTable r, relToParent=Just r{relTableAlias=maybe (relTable r) (QualifiedIdentifier mempty) parentAlias}, relAggAlias=aggAlias, fromAlias=newAlias}
-            _ ->
-              rPlan{from=relForeignTable r, relToParent=Just r, relAggAlias=aggAlias, fromAlias=newAlias, relJoinConds=getJoinConditions newAlias parentAlias r}
-          ) <$> rel
-        origin = if depth == 1 -- Only on depth 1 we check if the root(depth 0) has an alias so the sourceCTEName alias can be found as a relationship
-          then fromMaybe (qiName parentNodeQi) parentAlias
-          else qiName parentNodeQi
-        rel = findRel schema allRels origin relName relHint
-      in
-      Node <$> newReadPlan <*> (updateForest . hush $ Node <$> newReadPlan <*> pure forest)
-    Nothing -> -- root case
-      let
-        newFrom  = QualifiedIdentifier mempty sourceCTEName
-        newAlias = Just (qiName $ from rPlan)
-        newReadPlan = case action of
-          -- the CTE for mutations/rpc is used as WITH sourceCTEName .. SELECT .. FROM sourceCTEName as alias,
-          -- we use the table name as an alias so findRel can find the right relationship.
-          ActionMutate _ -> rPlan{from=newFrom, fromAlias=newAlias}
-          ActionInvoke _ -> rPlan{from=newFrom, fromAlias=newAlias}
-          _              -> rPlan
-      in
-      Node newReadPlan <$> updateForest (Just $ Node newReadPlan forest)
-  where
-    updateForest :: Maybe ReadPlanTree -> Either ApiRequestError [ReadPlanTree]
-    updateForest rq = addRels schema action allRels rq `traverse` forest
-
-getJoinConditions :: Maybe Alias -> Maybe Alias -> Relationship -> [JoinCondition]
-getJoinConditions _ _ ComputedRelationship{} = []
-getJoinConditions tblAlias parentAlias Relationship{relTable=qi,relForeignTable=fQi,relCardinality=card} =
-  case card of
-    M2M (Junction QualifiedIdentifier{qiName=jtn} _ _ jcols1 jcols2) ->
-      (toJoinCondition Nothing Nothing ftN jtn <$> jcols2) ++ (toJoinCondition parentAlias tblAlias tN jtn <$> jcols1)
-    O2M _ cols ->
-      toJoinCondition parentAlias tblAlias tN ftN <$> cols
-    M2O _ cols ->
-      toJoinCondition parentAlias tblAlias tN ftN <$> cols
-    O2O _ cols ->
-      toJoinCondition parentAlias tblAlias tN ftN <$> cols
-  where
-    QualifiedIdentifier{qiSchema=tSchema, qiName=tN} = qi
-    QualifiedIdentifier{qiName=ftN} = fQi
-    toJoinCondition :: Maybe Alias -> Maybe Alias -> Text -> Text -> (FieldName, FieldName) -> JoinCondition
-    toJoinCondition prAl newAl tb ftb (c, fc) =
-      let qi1 = QualifiedIdentifier tSchema ftb
-          qi2 = QualifiedIdentifier tSchema tb in
-        JoinCondition (maybe qi1 (QualifiedIdentifier mempty) newAl, fc)
-                      (maybe qi2 (QualifiedIdentifier mempty) prAl, c)
-
-- Finds a relationship between an origin and a target in the request:
-- /origin?select=target(*) If more than one relationship is found then the
-- request is ambiguous and we return an error.  In that case the request can
-- be disambiguated by adding precision to the target or by using a hint:
-- /origin?select=target!hint(*). The origin can be a table or view.
-findRel :: Schema -> RelationshipsMap -> NodeName -> NodeName -> Maybe Hint -> Either ApiRequestError Relationship
-findRel schema allRels origin target hint =
-  case rels of
-    []  -> Left $ NoRelBetween origin target hint schema allRels
-    [r] -> Right r
-    rs  -> Left $ AmbiguousRelBetween origin target rs
-  where
-    matchFKSingleCol hint_ card = case card of
-      O2M _ [(col, _)] -> hint_ == col
-      M2O _ [(col, _)] -> hint_ == col
-      O2O _ [(col, _)] -> hint_ == col
-      _                -> False
-    matchFKRefSingleCol hint_ card  = case card of
-      O2M _ [(_, fCol)] -> hint_ == fCol
-      M2O _ [(_, fCol)] -> hint_ == fCol
-      O2O _ [(_, fCol)] -> hint_ == fCol
-      _                 -> False
-    matchConstraint tar card = case card of
-      O2M cons _ -> tar == cons
-      M2O cons _ -> tar == cons
-      O2O cons _ -> tar == cons
-      _          -> False
-    matchJunction hint_ card = case card of
-      M2M Junction{junTable} -> hint_ == qiName junTable
-      _                      -> False
-    isM2O card = case card of
-      M2O _ _ -> True
-      _       -> False
-    isO2M card = case card of
-      O2M _ _ -> True
-      _       -> False
-    rels = filter (\case
-      ComputedRelationship{relFunction} -> target == qiName relFunction
-      Relationship{..} ->
-        -- In a self-relationship we have a single foreign key but two relationships with different cardinalities: M2O/O2M. For disambiguation, we use the convention of getting:
-        -- TODO: handle one-to-one and many-to-many self-relationships
-        if relIsSelf
-        then case hint of
-          Nothing ->
-            -- The O2M by using the table name in the target
-            target == qiName relForeignTable && isO2M relCardinality -- /family_tree?select=children:family_tree(*)
-            ||
-            -- The M2O by using the column name in the target
-            matchFKSingleCol target relCardinality && isM2O relCardinality -- /family_tree?select=parent(*)
-          Just hnt ->
-            -- /organizations?select=auditees:organizations!auditor(*)
-            target == qiName relForeignTable && isO2M relCardinality
-            && matchFKRefSingleCol hnt relCardinality -- auditor
-        else case hint of
-          -- DEPRECATED(remove after 2 major releases since v11.1.0): remove target
-          -- target = table / view / constraint / column-from-origin (constraint/column-from-origin can only come from tables https://github.com/PostgREST/postgrest/issues/2277)
-          -- DEPRECATED(remove after 2 major releases since v11.1.0): remove hint as table/view/columns and only leave it as constraint
-          -- hint   = table / view / constraint / column-from-origin / column-from-target (hint can take table / view values to aid in finding the junction in an m2m relationship)
-          Nothing ->
-              -- /projects?select=clients(*)
-              target == qiName relForeignTable -- clients
-              ||
-              -- /projects?select=projects_client_id_fkey(*)
-              matchConstraint target relCardinality -- projects_client_id_fkey
-              && not relFTableIsView
-              ||
-              -- /projects?select=client_id(*)
-              matchFKSingleCol target relCardinality -- client_id
-              && not relFTableIsView
-          Just hnt ->
-            -- /projects?select=clients(*)
-            target == qiName relForeignTable -- clients
-            && (
-              -- /projects?select=clients!projects_client_id_fkey(*)
-              matchConstraint hnt relCardinality || -- projects_client_id_fkey
-
-              -- /projects?select=clients!client_id(*) or /projects?select=clients!id(*)
-              matchFKSingleCol hnt relCardinality      || -- client_id
-              matchFKRefSingleCol hnt relCardinality   || -- id
-
-              -- /users?select=tasks!users_tasks(*) many-to-many between users and tasks
-              matchJunction hnt relCardinality -- users_tasks
-            )
-      ) $ fromMaybe mempty $ HM.lookup (QualifiedIdentifier schema origin, schema) allRels
-
-addFilters :: ResolverContext -> ApiRequest -> ReadPlanTree -> Either ApiRequestError ReadPlanTree
-addFilters ctx ApiRequest{..} rReq =
-  foldr addFilterToNode (Right rReq) flts
-  where
-    QueryParams.QueryParams{..} = iQueryParams
-    flts =
-      case iAction of
-        ActionInvoke _ -> qsFilters
-        ActionRead _   -> qsFilters
-        _              -> qsFiltersNotRoot
-
-    addFilterToNode :: (EmbedPath, Filter) -> Either ApiRequestError ReadPlanTree ->  Either ApiRequestError ReadPlanTree
-    addFilterToNode =
-      updateNode (\flt (Node q@ReadPlan{from=fromTable, where_=lf} f) -> Node q{ReadPlan.where_=addFilterToLogicForest (resolveFilter ctx{qi=fromTable} flt) lf}  f)
-
-addOrders :: ResolverContext -> ApiRequest -> ReadPlanTree -> Either ApiRequestError ReadPlanTree
-addOrders ctx ApiRequest{..} rReq =
-  case iAction of
-    ActionMutate _ -> Right rReq
-    _              -> foldr addOrderToNode (Right rReq) qsOrder
-  where
-    QueryParams.QueryParams{..} = iQueryParams
-
-    addOrderToNode :: (EmbedPath, [OrderTerm]) -> Either ApiRequestError ReadPlanTree -> Either ApiRequestError ReadPlanTree
-    addOrderToNode = updateNode (\o (Node q f) -> Node q{order=resolveOrder ctx <$> o} f)
-
-resolveOrder :: ResolverContext -> OrderTerm -> CoercibleOrderTerm
-resolveOrder _ (OrderRelationTerm a b c d) = CoercibleOrderRelationTerm a b c d
-resolveOrder ctx (OrderTerm fld dir nulls) = CoercibleOrderTerm (resolveTypeOrUnknown ctx fld) dir nulls
-
-- Validates that the related resource on the order is an embedded resource,
-- e.g. if `clients` is inside the `select` in /projects?order=clients(id)&select=*,clients(*),
-- and if it's a to-one relationship, it adds the right alias to the OrderRelationTerm so the generated query can succeed.
-addRelatedOrders :: ReadPlanTree -> Either ApiRequestError ReadPlanTree
-addRelatedOrders (Node rp@ReadPlan{order,from} forest) = do
-  newOrder <- newRelOrder `traverse` order
-  Node rp{order=newOrder} <$> addRelatedOrders `traverse` forest
-  where
-    newRelOrder cot@CoercibleOrderTerm{}                   = Right cot
-    newRelOrder cot@CoercibleOrderRelationTerm{coRelation} =
-      let foundRP = rootLabel <$> find (\(Node ReadPlan{relName, relAlias} _) -> coRelation == fromMaybe relName relAlias) forest in
-      case foundRP of
-        Just ReadPlan{relName,relAlias,relAggAlias,relToParent} ->
-          let isToOne = relIsToOne <$> relToParent
-              name    = fromMaybe relName relAlias in
-          if isToOne == Just True
-            then Right $ cot{coRelation=relAggAlias}
-            else Left $ RelatedOrderNotToOne (qiName from) name
-        Nothing ->
-          Left $ NotEmbedded coRelation
-
-- | Searches for null filters on embeds, e.g. `projects=not.is.null` on `GET /clients?select=*,projects(*)&projects=not.is.null`
--
-- (It doesn't err but uses an Either ApiRequestError type so it can combine with the other functions that modify the read plan tree)
--
-- Setup:
--
-- >>> let nullOp    = OpExpr True (Is TriNull)
-- >>> let nonNullOp = OpExpr False (Is TriNull)
-- >>> let notEqOp   = OpExpr True (Op OpNotEqual "val")
-- >>> :{
-- -- this represents the `projects(*)` part on `/clients?select=*,projects(*)`
-- let
-- subForestPlan =
--   [
--     Node {
--       rootLabel = ReadPlan {
--         select = [], -- there will be fields at this stage but we just omit them for brevity
--         from = QualifiedIdentifier {qiSchema = "test", qiName = "projects"},
--         fromAlias = Just "projects_1", where_ = [], order = [], range_ = fullRange,
--         relName = "projects",
--         relToParent = Nothing,
--         relJoinConds = [],
--         relAlias = Nothing, relAggAlias = "clients_projects_1", relHint = Nothing, relJoinType = Nothing, relIsSpread = False, depth = 1
--       },
--       subForest = []
--     }
--   ]
-- :}
--
-- >>> :{
-- -- this represents the full URL `/clients?select=*,projects(*)&projects=not.is.null`, if subForst takes the above subForestPlan and nullOp
-- let
-- readPlanTree op subForst =
--   Node {
--     rootLabel = ReadPlan {
--       select = [], -- there will be fields at this stage but we just omit them for brevity
--       from = QualifiedIdentifier { qiSchema = "test", qiName = "clients"},
--       fromAlias = Nothing,
--       where_ = [
--         CoercibleStmnt (
--           CoercibleFilter {
--            field = CoercibleField {cfName = "projects", cfJsonPath = [], cfToJson=False, cfIRType = "", cfTransform = Nothing, cfDefault = Nothing},
--            opExpr = op
--           }
--         )
--       ],
--       order = [], range_ = fullRange, relName = "clients", relToParent = Nothing, relJoinConds = [], relAlias = Nothing, relAggAlias = "", relHint = Nothing,
--       relJoinType = Nothing, relIsSpread = False, depth = 0
--     },
--     subForest = subForst
--   }
-- :}
--
-- Don't do anything to the filter if there's no embedding (a subtree) on projects. Assume it's a normal filter.
--
-- >>> ReadPlan.where_ . rootLabel <$> addNullEmbedFilters (readPlanTree nullOp [])
-- Right [CoercibleStmnt (CoercibleFilter {field = CoercibleField {cfName = "projects", cfJsonPath = [], cfToJson = False, cfIRType = "", cfTransform = Nothing, cfDefault = Nothing}, opExpr = OpExpr True (Is TriNull)})]
--
-- If there's an embedding on projects, then change the filter to use the internal aggregate name (`clients_projects_1`) so the filter can succeed later.
--
-- >>> ReadPlan.where_ . rootLabel <$> addNullEmbedFilters (readPlanTree nullOp subForestPlan)
-- Right [CoercibleStmnt (CoercibleFilterNullEmbed True "clients_projects_1")]
--
-- >>> ReadPlan.where_ . rootLabel <$> addNullEmbedFilters (readPlanTree nonNullOp subForestPlan)
-- Right [CoercibleStmnt (CoercibleFilterNullEmbed False "clients_projects_1")]
-addNullEmbedFilters :: ReadPlanTree -> Either ApiRequestError ReadPlanTree
-addNullEmbedFilters (Node rp@ReadPlan{where_=curLogic} forest) = do
-  let forestReadPlans = rootLabel <$> forest
-  newLogic <- newNullFilters forestReadPlans `traverse` curLogic
-  Node rp{ReadPlan.where_= newLogic} <$> (addNullEmbedFilters `traverse` forest)
-  where
-    newNullFilters :: [ReadPlan] -> CoercibleLogicTree -> Either ApiRequestError CoercibleLogicTree
-    newNullFilters rPlans = \case
-      (CoercibleExpr b lOp trees) ->
-        CoercibleExpr b lOp <$> (newNullFilters rPlans `traverse` trees)
-      flt@(CoercibleStmnt (CoercibleFilter (CoercibleField fld [] _ _ _ _) opExpr)) ->
-        let foundRP = find (\ReadPlan{relName, relAlias} -> fld == fromMaybe relName relAlias) rPlans in
-        case (foundRP, opExpr) of
-          (Just ReadPlan{relAggAlias}, OpExpr b (Is TriNull)) -> Right $ CoercibleStmnt $ CoercibleFilterNullEmbed b relAggAlias
-          _                                                   -> Right flt
-      flt@(CoercibleStmnt _) ->
-        Right flt
-
-addRanges :: ApiRequest -> ReadPlanTree -> Either ApiRequestError ReadPlanTree
-addRanges ApiRequest{..} rReq =
-  case iAction of
-    ActionMutate _ -> Right rReq
-    _              -> foldr addRangeToNode (Right rReq) =<< ranges
-  where
-    ranges :: Either ApiRequestError [(EmbedPath, NonnegRange)]
-    ranges = first QueryParamError $ QueryParams.pRequestRange `traverse` HM.toList iRange
-
-    addRangeToNode :: (EmbedPath, NonnegRange) -> Either ApiRequestError ReadPlanTree -> Either ApiRequestError ReadPlanTree
-    addRangeToNode = updateNode (\r (Node q f) -> Node q{range_=r} f)
-
-addLogicTrees :: ResolverContext -> ApiRequest -> ReadPlanTree -> Either ApiRequestError ReadPlanTree
-addLogicTrees ctx ApiRequest{..} rReq =
-  foldr addLogicTreeToNode (Right rReq) qsLogic
-  where
-    QueryParams.QueryParams{..} = iQueryParams
-
-    addLogicTreeToNode :: (EmbedPath, LogicTree) -> Either ApiRequestError ReadPlanTree -> Either ApiRequestError ReadPlanTree
-    addLogicTreeToNode = updateNode (\t (Node q@ReadPlan{from=fromTable, where_=lf} f) -> Node q{ReadPlan.where_=resolveLogicTree ctx{qi=fromTable} t:lf} f)
-
-resolveLogicTree :: ResolverContext -> LogicTree -> CoercibleLogicTree
-resolveLogicTree ctx (Stmnt flt) = CoercibleStmnt $ resolveFilter ctx flt
-resolveLogicTree ctx (Expr b op lts) = CoercibleExpr b op (map (resolveLogicTree ctx) lts)
-
-resolveFilter :: ResolverContext -> Filter -> CoercibleFilter
-resolveFilter ctx (Filter fld opExpr) = CoercibleFilter{field=resolveQueryInputField ctx fld, opExpr=opExpr}
-
-- Validates that spread embeds are only done on to-one relationships
-validateSpreadEmbeds :: ReadPlanTree -> Either ApiRequestError ReadPlanTree
-validateSpreadEmbeds (Node rp@ReadPlan{relToParent=Nothing} forest) = Node rp <$> validateSpreadEmbeds `traverse` forest
-validateSpreadEmbeds (Node rp@ReadPlan{relIsSpread,relToParent=Just rel,relName} forest) = do
-  validRP <- if relIsSpread && not (relIsToOne rel)
-    then Left $ SpreadNotToOne (qiName $ relTable rel) relName -- TODO using relTable is not entirely right because ReadPlan might have an alias, need to store the parent alias on ReadPlan
-    else Right rp
-  Node validRP <$> validateSpreadEmbeds `traverse` forest
-
-- Find a Node of the Tree and apply a function to it
-updateNode :: (a -> ReadPlanTree -> ReadPlanTree) -> (EmbedPath, a) -> Either ApiRequestError ReadPlanTree -> Either ApiRequestError ReadPlanTree
-updateNode f ([], a) rr = f a <$> rr
-updateNode _ _ (Left e) = Left e
-updateNode f (targetNodeName:remainingPath, a) (Right (Node rootNode forest)) =
-  case findNode of
-    Nothing -> Left $ NotEmbedded targetNodeName
-    Just target ->
-      (\node -> Node rootNode $ node : delete target forest) <$>
-      updateNode f (remainingPath, a) (Right target)
-  where
-    findNode :: Maybe ReadPlanTree
-    findNode = find (\(Node ReadPlan{relName, relAlias} _) -> relName == targetNodeName || relAlias == Just targetNodeName) forest
-
-mutatePlan :: Mutation -> QualifiedIdentifier -> ApiRequest -> SchemaCache -> ReadPlanTree -> Either Error MutatePlan
-mutatePlan mutation qi ApiRequest{iPreferences=Preferences{..}, ..} SchemaCache{dbTables, dbRepresentations} readReq = mapLeft ApiRequestError $
-  case mutation of
-    MutationCreate ->
-      mapRight (\typedColumns -> Insert qi typedColumns body ((,) <$> preferResolution <*> Just confCols) [] returnings pkCols applyDefaults) typedColumnsOrError
-    MutationUpdate ->
-      mapRight (\typedColumns -> Update qi typedColumns body combinedLogic iTopLevelRange rootOrder returnings applyDefaults) typedColumnsOrError
-    MutationSingleUpsert ->
-        if null qsLogic &&
-           qsFilterFields == S.fromList pkCols &&
-           not (null (S.fromList pkCols)) &&
-           all (\case
-              Filter _ (OpExpr False (OpQuant OpEqual Nothing _)) -> True
-              _                                                   -> False) qsFiltersRoot
-          then mapRight (\typedColumns -> Insert qi typedColumns body (Just (MergeDuplicates, pkCols)) combinedLogic returnings mempty False) typedColumnsOrError
-        else
-          Left InvalidFilters
-    MutationDelete -> Right $ Delete qi combinedLogic iTopLevelRange rootOrder returnings
-  where
-    ctx = ResolverContext dbTables dbRepresentations qi "json"
-    confCols = fromMaybe pkCols qsOnConflict
-    QueryParams.QueryParams{..} = iQueryParams
-    returnings =
-      if preferRepresentation == Just None || isNothing preferRepresentation
-        then []
-        else inferColsEmbedNeeds readReq pkCols
-    tbl = HM.lookup qi dbTables
-    pkCols = maybe mempty tablePKCols tbl
-    logic = map (resolveLogicTree ctx . snd) qsLogic
-    rootOrder = resolveOrder ctx <$> maybe [] snd (find (\(x, _) -> null x) qsOrder)
-    combinedLogic = foldr (addFilterToLogicForest . resolveFilter ctx) logic qsFiltersRoot
-    body = payRaw <$> iPayload -- the body is assumed to be json at this stage(ApiRequest validates)
-    applyDefaults = preferMissing == Just ApplyDefaults
-    typedColumnsOrError = resolveOrError ctx tbl `traverse` S.toList iColumns
-
-resolveOrError :: ResolverContext -> Maybe Table -> FieldName -> Either ApiRequestError CoercibleField
-resolveOrError _ Nothing _ = Left NotFound
-resolveOrError ctx (Just table) field =
-  case resolveTableFieldName table field of
-    CoercibleField{cfIRType=""} -> Left $ ColumnNotFound (tableName table) field
-    cf                          -> Right $ withJsonParse ctx cf
-
-callPlan :: Routine -> ApiRequest -> S.Set FieldName -> LBS.ByteString -> ReadPlanTree -> CallPlan
-callPlan proc ApiRequest{iPreferences=Preferences{..}} paramKeys args readReq = FunctionCall {
-  funCQi = QualifiedIdentifier (pdSchema proc) (pdName proc)
-, funCParams = callParams
-, funCArgs = Just args
-, funCScalar = funcReturnsScalar proc
-, funCSetOfScalar = funcReturnsSetOfScalar proc
-, funCRetCompositeAlias = funcReturnsCompositeAlias proc
-, funCReturning = inferColsEmbedNeeds readReq []
-}
-  where
-    paramsAsSingleObject = preferParameters == Just SingleObject
-    specifiedParams = filter (\x -> ppName x `S.member` paramKeys)
-    callParams = case pdParams proc of
-      [prm] | paramsAsSingleObject -> OnePosParam prm
-            | ppName prm == mempty -> OnePosParam prm
-            | otherwise            -> KeyParams $ specifiedParams [prm]
-      prms  -> KeyParams $ specifiedParams prms
-
-- | Infers the columns needed for an embed to be successful after a mutation or a function call.
-inferColsEmbedNeeds :: ReadPlanTree -> [FieldName] -> [FieldName]
-inferColsEmbedNeeds (Node ReadPlan{select} forest) pkCols
-  -- if * is part of the select, we must not add pk or fk columns manually -
-  -- otherwise those would be selected and output twice
-  | "*" `elem` fldNames = ["*"]
-  | otherwise           = returnings
-  where
-    fldNames = cfName . (\(f, _, _) -> f) <$> select
-    -- Without fkCols, when a mutatePlan to
-    -- /projects?select=name,clients(name) occurs, the RETURNING SQL part would
-    -- be `RETURNING name`(see QueryBuilder).  This would make the embedding
-    -- fail because the following JOIN would need the "client_id" column from
-    -- projects.  So this adds the foreign key columns to ensure the embedding
-    -- succeeds, result would be `RETURNING name, client_id`.
-    fkCols = concat $ mapMaybe (\case
-        Node ReadPlan{relToParent=Just Relationship{relCardinality=O2M _ cols}} _ ->
-          Just $ fst <$> cols
-        Node ReadPlan{relToParent=Just Relationship{relCardinality=M2O _ cols}} _ ->
-          Just $ fst <$> cols
-        Node ReadPlan{relToParent=Just Relationship{relCardinality=O2O _ cols}} _ ->
-          Just $ fst <$> cols
-        Node ReadPlan{relToParent=Just Relationship{relCardinality=M2M Junction{junColsSource=cols}}} _ ->
-          Just $ fst <$> cols
-        Node ReadPlan{relToParent=Just ComputedRelationship{}} _ ->
-          Nothing
-        Node ReadPlan{relToParent=Nothing} _ ->
-          Nothing
-      ) forest
-    hasComputedRel = isJust $ find (\case
-      Node ReadPlan{relToParent=Just ComputedRelationship{}} _ -> True
-      _                                                    -> False
-      ) forest
-    -- However if the "client_id" is present, e.g. mutatePlan to
-    -- /projects?select=client_id,name,clients(name) we would get `RETURNING
-    -- client_id, name, client_id` and then we would produce the "column
-    -- reference \"client_id\" is ambiguous" error from PostgreSQL. So we
-    -- deduplicate with Set: We are adding the primary key columns as well to
-    -- make sure, that a proper location header can always be built for
-    -- INSERT/POST
-    returnings =
-      if not hasComputedRel
-        then S.toList . S.fromList $ fldNames ++ fkCols ++ pkCols
-        else ["*"] -- on computed relationships we cannot know the required columns for an embedding to succeed, so we just return all
-
-- Traditional filters(e.g. id=eq.1) are added as root nodes of the LogicTree
-- they are later concatenated with AND in the QueryBuilder
-addFilterToLogicForest :: CoercibleFilter -> [CoercibleLogicTree] -> [CoercibleLogicTree]
-addFilterToLogicForest flt lf = CoercibleStmnt flt : lf
-
-- | If raw(binary) output is requested, check that MediaType is one of the
-- admitted rawMediaTypes and that`?select=...` contains only one field other
-- than `*`
-binaryField :: AppConfig -> MediaType -> Maybe Routine -> ReadPlanTree -> Either ApiRequestError (Maybe FieldName)
-binaryField AppConfig{configRawMediaTypes} acceptMediaType proc rpTree
-  | isRawMediaType =
-    if (funcReturnsScalar <$> proc) == Just True ||
-       (funcReturnsSetOfScalar <$> proc) == Just True
-      then Right $ Just "pgrst_scalar"
-      else
-        let
-          fieldName = fstFieldName rpTree
-        in
-        case fieldName of
-          Just fld -> Right $ Just fld
-          Nothing  -> Left $ BinaryFieldError acceptMediaType
-  | otherwise =
-      Right Nothing
-  where
-    isRawMediaType = acceptMediaType `elem` configRawMediaTypes `L.union` [MTOctetStream, MTTextPlain, MTTextXML] || isRawPlan acceptMediaType
-    isRawPlan mt = case mt of
-      MTPlan MTOctetStream _ _ -> True
-      MTPlan MTTextPlain _ _   -> True
-      MTPlan MTTextXML _ _     -> True
-      _                        -> False
-
-    fstFieldName :: ReadPlanTree -> Maybe FieldName
-    fstFieldName (Node ReadPlan{select=(CoercibleField{cfName="*", cfJsonPath=[]}, _, _):_} [])  = Nothing
-    fstFieldName (Node ReadPlan{select=[(CoercibleField{cfName=fld, cfJsonPath=[]}, _, _)]} [])  = Just fld
-    fstFieldName _                                               = Nothing
-
-
-mediaToAggregate :: MediaType -> Maybe FieldName -> ApiRequest -> ResultAggregate
-mediaToAggregate mt binField apiReq@ApiRequest{iAction=act, iPreferences=Preferences{preferRepresentation=rep}} =
-  if noAgg then NoAgg
-  else case mt of
-    MTApplicationJSON     -> BuiltinAggJson
-    MTSingularJSON strip  -> BuiltinAggSingleJson strip
-    MTArrayJSONStrip      -> BuiltinAggArrayJsonStrip
-    MTGeoJSON             -> BuiltinAggGeoJson
-    MTTextCSV             -> BuiltinAggCsv
-    MTAny                 -> BuiltinAggJson
-    MTOpenAPI             -> BuiltinAggJson
-    MTUrlEncoded          -> NoAgg -- TODO: unreachable since a previous step (producedMediaTypes) whitelists the media types that can become aggregates.
-
-    -- binary types
-    MTTextPlain           -> BuiltinAggBinary binField
-    MTTextXML             -> BuiltinAggXml binField
-    MTOctetStream         -> BuiltinAggBinary binField
-    MTOther _             -> BuiltinAggBinary binField
-
-    -- Doing `Accept: application/vnd.pgrst.plan; for="application/vnd.pgrst.plan"` doesn't make sense, so we just empty the body.
-    -- TODO: fail instead to be more strict
-    MTPlan (MTPlan{}) _ _ -> NoAgg
-    MTPlan media      _ _ -> mediaToAggregate media binField apiReq
-  where
-    noAgg = case act of
-      ActionMutate _         -> rep == Just HeadersOnly || rep == Just None || isNothing rep
-      ActionRead _isHead     -> _isHead -- no need for an aggregate on HEAD https://github.com/PostgREST/postgrest/issues/2849
-      ActionInvoke invMethod -> invMethod == InvHead
-      _                      -> False
@@ -1,57 +0,0 @@
-{-# LANGUAGE NamedFieldPuns #-}
-module PostgREST.Plan.CallPlan
-  ( CallPlan(..)
-  , CallParams(..)
-  , jsonRpcParams
-  )
-where
-
-import qualified Data.Aeson                        as JSON
-import qualified Data.ByteString.Lazy              as LBS
-import qualified Data.HashMap.Strict               as HM
-import           PostgREST.SchemaCache.Identifiers (FieldName,
-                                                    QualifiedIdentifier)
-import           PostgREST.SchemaCache.Routine     (Routine (..),
-                                                    RoutineParam (..))
-
-import Protolude
-
-data CallPlan = FunctionCall
-  { funCQi                :: QualifiedIdentifier
-  , funCParams            :: CallParams
-  , funCArgs              :: Maybe LBS.ByteString
-  , funCScalar            :: Bool
-  , funCSetOfScalar       :: Bool
-  , funCRetCompositeAlias :: Bool
-  , funCReturning         :: [FieldName]
-  }
-
-data CallParams
-  = KeyParams [RoutineParam] -- ^ Call with key params: func(a := val1, b:= val2)
-  | OnePosParam RoutineParam -- ^ Call with positional params(only one supported): func(val)
-
-- | Convert rpc params `/rpc/func?a=val1&b=val2` to json `{"a": "val1", "b": "val2"}
-jsonRpcParams :: Routine -> [(Text, Text)] -> LBS.ByteString
-jsonRpcParams proc prms =
-  if not $ pdHasVariadic proc then -- if proc has no variadic param, save steps and directly convert to json
-    JSON.encode $ HM.fromList $ second JSON.toJSON <$> prms
-  else
-    let paramsMap = HM.fromListWith mergeParams $ toRpcParamValue proc <$> prms in
-    JSON.encode paramsMap
-  where
-    mergeParams :: RpcParamValue -> RpcParamValue -> RpcParamValue
-    mergeParams (Variadic a) (Variadic b) = Variadic $ b ++ a
-    mergeParams v _                       = v -- repeated params for non-variadic parameters are not merged
-
-toRpcParamValue :: Routine -> (Text, Text) -> (Text, RpcParamValue)
-toRpcParamValue proc (k, v) | prmIsVariadic k = (k, Variadic [v])
-                            | otherwise       = (k, Fixed v)
-  where
-    prmIsVariadic prm = isJust $ find (\RoutineParam{ppName, ppVar} -> ppName == prm && ppVar) $ pdParams proc
-
-- | RPC query param value `/rpc/func?v=<value>`, used for VARIADIC functions on form-urlencoded POST and GETs
-- | It can be fixed `?v=1` or repeated `?v=1&v=2&v=3.
-data RpcParamValue = Fixed Text | Variadic [Text]
-instance JSON.ToJSON RpcParamValue where
-  toJSON (Fixed    v) = JSON.toJSON v
-  toJSON (Variadic v) = JSON.toJSON v
@@ -1,46 +0,0 @@
-module PostgREST.Plan.MutatePlan
-  ( MutatePlan(..)
-  )
-where
-
-import qualified Data.ByteString.Lazy as LBS
-
-import PostgREST.ApiRequest.Preferences  (PreferResolution)
-import PostgREST.Plan.Types              (CoercibleField,
-                                          CoercibleLogicTree,
-                                          CoercibleOrderTerm)
-import PostgREST.RangeQuery              (NonnegRange)
-import PostgREST.SchemaCache.Identifiers (FieldName,
-                                          QualifiedIdentifier)
-
-
-import Protolude
-
-data MutatePlan
-  = Insert
-      { in_        :: QualifiedIdentifier
-      , insCols    :: [CoercibleField]
-      , insBody    :: Maybe LBS.ByteString
-      , onConflict :: Maybe (PreferResolution, [FieldName])
-      , where_     :: [CoercibleLogicTree]
-      , returning  :: [FieldName]
-      , insPkCols  :: [FieldName]
-      , applyDefs  :: Bool
-      }
-  | Update
-      { in_       :: QualifiedIdentifier
-      , updCols   :: [CoercibleField]
-      , updBody   :: Maybe LBS.ByteString
-      , where_    :: [CoercibleLogicTree]
-      , mutRange  :: NonnegRange
-      , mutOrder  :: [CoercibleOrderTerm]
-      , returning :: [FieldName]
-      , applyDefs :: Bool
-      }
-  | Delete
-      { in_       :: QualifiedIdentifier
-      , where_    :: [CoercibleLogicTree]
-      , mutRange  :: NonnegRange
-      , mutOrder  :: [CoercibleOrderTerm]
-      , returning :: [FieldName]
-      }
@@ -1,48 +0,0 @@
-module PostgREST.Plan.ReadPlan
-  ( ReadPlanTree
-  , ReadPlan(..)
-  , JoinCondition(..)
-  ) where
-
-import Data.Tree (Tree (..))
-
-import PostgREST.ApiRequest.Types         (Alias, Cast, Depth, Hint,
-                                           JoinType, NodeName)
-import PostgREST.Plan.Types               (CoercibleField (..),
-                                           CoercibleLogicTree,
-                                           CoercibleOrderTerm)
-import PostgREST.RangeQuery               (NonnegRange)
-import PostgREST.SchemaCache.Identifiers  (FieldName,
-                                           QualifiedIdentifier)
-import PostgREST.SchemaCache.Relationship (Relationship)
-
-
-import Protolude
-
-type ReadPlanTree = Tree ReadPlan
-
-data JoinCondition =
-  JoinCondition
-    (QualifiedIdentifier, FieldName)
-    (QualifiedIdentifier, FieldName)
-  deriving (Eq, Show)
-
-data ReadPlan = ReadPlan
-  { select       :: [(CoercibleField, Maybe Cast, Maybe Alias)]
-  , from         :: QualifiedIdentifier
-  , fromAlias    :: Maybe Alias
-  , where_       :: [CoercibleLogicTree]
-  , order        :: [CoercibleOrderTerm]
-  , range_       :: NonnegRange
-  , relName      :: NodeName
-  , relToParent  :: Maybe Relationship
-  , relJoinConds :: [JoinCondition]
-  , relAlias     :: Maybe Alias
-  , relAggAlias  :: Alias
-  , relHint      :: Maybe Hint
-  , relJoinType  :: Maybe JoinType
-  , relIsSpread  :: Bool
-  , depth        :: Depth
-  -- ^ used for aliasing
-  }
-  deriving (Eq, Show)
@@ -1,67 +0,0 @@
-module PostgREST.Plan.Types
-  ( CoercibleField(..)
-  , unknownField
-  , CoercibleLogicTree(..)
-  , CoercibleFilter(..)
-  , TransformerProc
-  , CoercibleOrderTerm(..)
-  ) where
-
-import PostgREST.ApiRequest.Types (Field, JsonPath, LogicOperator,
-                                   OpExpr, OrderDirection, OrderNulls)
-
-import PostgREST.SchemaCache.Identifiers (FieldName)
-
-import Protolude
-
-type TransformerProc = Text
-
-- | A CoercibleField pairs the name of a query element with any type coercion information we need for some specific use case.
-- |
-- | As suggested by the name, it's often a reference to a field in a table but really it can be any nameable element (function parameter, calculation with an alias, etc) with a knowable type.
-- |
-- | In the simplest case, it allows us to parse JSON payloads with `json_to_recordset`, for which we need to know both the name and the type of each thing we'd like to extract. At a higher level, CoercibleField generalises to reflect that any value we work with in a query may need type specific handling.
-- |
-- | CoercibleField is the foundation for the Data Representations feature. This feature allow user-definable mappings between database types so that the same data can be presented or interpreted in various ways as needed. Sometimes the way Postgres coerces data implicitly isn't right for the job. Different mappings might be appropriate for different situations: parsing a filter from a query string requires one function (text -> field type) while parsing a payload from JSON takes another (json -> field type). And the reverse, outputting a field as JSON, requires yet a third (field type -> json). CoercibleField is that "job specific" reference to an element paired with the type we desire for that particular purpose and the function we'll use to get there, if any.
-- |
-- | In the planning phase, we "resolve" generic named elements into these specialised CoercibleFields. Again this is context specific: two different CoercibleFields both representing the exact same table column in the database, even in the same query, might have two different target types and mapping functions. For example, one might represent a column in a filter, and another the very same column in an output role to be sent in the response body.
-- |
-- | The type value is allowed to be the empty string. The analog here is soft type checking in programming languages: sometimes we don't need a variable to have a specified type and things will work anyhow. So the empty type variant is valid when we don't know and *don't need to know* about the specific type in some context. Note that this variation should not be used if it guarantees failure: in that case you should instead raise an error at the planning stage and bail out. For example, we can't parse JSON with `json_to_recordset` without knowing the types of each recipient field, and so error out. Using the empty string for the type would be incorrect and futile. On the other hand we use the empty type for RPC calls since type resolution isn't implemented for RPC, but it's fine because the query still works with Postgres' implicit coercion. In the future, hopefully we will support data representations across the board and then the empty type may be permanently retired.
-data CoercibleField = CoercibleField
-  { cfName      :: FieldName
-  , cfJsonPath  :: JsonPath
-  , cfToJson    :: Bool
-  , cfIRType    :: Text                  -- ^ The native Postgres type of the field, the intermediate (IR) type before mapping.
-  , cfTransform :: Maybe TransformerProc -- ^ The optional mapping from irType -> targetType.
-  , cfDefault   :: Maybe Text
-  } deriving (Eq, Show)
-
-unknownField :: FieldName -> JsonPath -> CoercibleField
-unknownField name path = CoercibleField name path False "" Nothing Nothing
-
-- | Like an API request LogicTree, but with coercible field information.
-data CoercibleLogicTree
-  = CoercibleExpr Bool LogicOperator [CoercibleLogicTree]
-  | CoercibleStmnt CoercibleFilter
-  deriving (Eq, Show)
-
-data CoercibleFilter = CoercibleFilter
-  { field  :: CoercibleField
-  , opExpr :: OpExpr
-  }
-  | CoercibleFilterNullEmbed Bool FieldName
-  deriving (Eq, Show)
-
-data CoercibleOrderTerm
-  = CoercibleOrderTerm
-    { coField     :: CoercibleField
-    , coDirection :: Maybe OrderDirection
-    , coNullOrder :: Maybe OrderNulls
-    }
-  | CoercibleOrderRelationTerm
-    { coRelation  :: FieldName
-    , coRelTerm   :: Field
-    , coDirection :: Maybe OrderDirection
-    , coNullOrder :: Maybe OrderNulls
-    }
-  deriving (Eq, Show)
@@ -1,274 +0,0 @@
-{-# LANGUAGE NamedFieldPuns  #-}
-{-# LANGUAGE RecordWildCards #-}
-module PostgREST.Query
-  ( createQuery
-  , deleteQuery
-  , invokeQuery
-  , openApiQuery
-  , readQuery
-  , singleUpsertQuery
-  , updateQuery
-  , setPgLocals
-  , runPreReq
-  , DbHandler
-  ) where
-
-import qualified Data.Aeson                        as JSON
-import qualified Data.Aeson.Key                    as K
-import qualified Data.Aeson.KeyMap                 as KM
-import qualified Data.ByteString                   as BS
-import qualified Data.ByteString.Lazy.Char8        as LBS
-import qualified Data.HashMap.Strict               as HM
-import qualified Data.Set                          as S
-import qualified Data.Text.Encoding                as T
-import qualified Hasql.Decoders                    as HD
-import qualified Hasql.DynamicStatements.Snippet   as SQL (Snippet)
-import qualified Hasql.DynamicStatements.Statement as SQL
-import qualified Hasql.Transaction                 as SQL
-
-import qualified PostgREST.Error              as Error
-import qualified PostgREST.Query.QueryBuilder as QueryBuilder
-import qualified PostgREST.Query.Statements   as Statements
-import qualified PostgREST.RangeQuery         as RangeQuery
-import qualified PostgREST.SchemaCache        as SchemaCache
-
-import Data.Scientific (FPFormat (..), formatScientific, isInteger)
-
-import PostgREST.ApiRequest              (ApiRequest (..))
-import PostgREST.ApiRequest.Preferences  (PreferCount (..),
-                                          PreferTransaction (..),
-                                          Preferences (..),
-                                          shouldCount)
-import PostgREST.Config                  (AppConfig (..),
-                                          OpenAPIMode (..))
-import PostgREST.Config.PgVersion        (PgVersion (..),
-                                          pgVersion140)
-import PostgREST.Error                   (Error)
-import PostgREST.MediaType               (MediaType (..))
-import PostgREST.Plan                    (CallReadPlan (..),
-                                          MutateReadPlan (..),
-                                          WrappedReadPlan (..))
-import PostgREST.Plan.MutatePlan         (MutatePlan (..))
-import PostgREST.Query.SqlFragment       (escapeIdentList, fromQi,
-                                          intercalateSnippet,
-                                          setConfigLocal,
-                                          setConfigLocalJson)
-import PostgREST.Query.Statements        (ResultSet (..))
-import PostgREST.SchemaCache             (SchemaCache (..))
-import PostgREST.SchemaCache.Identifiers (QualifiedIdentifier (..),
-                                          Schema)
-import PostgREST.SchemaCache.Routine     (Routine (..), RoutineMap)
-import PostgREST.SchemaCache.Table       (TablesMap)
-
-import Protolude hiding (Handler)
-
-type DbHandler = ExceptT Error SQL.Transaction
-
-readQuery :: WrappedReadPlan -> AppConfig -> ApiRequest -> DbHandler ResultSet
-readQuery WrappedReadPlan{wrReadPlan, wrResAgg} conf@AppConfig{..} apiReq@ApiRequest{iPreferences=Preferences{..}, ..} = do
-  let countQuery = QueryBuilder.readPlanToCountQuery wrReadPlan
-  resultSet <-
-     lift . SQL.statement mempty $
-      Statements.prepareRead
-        (QueryBuilder.readPlanToQuery wrReadPlan)
-        (if preferCount == Just EstimatedCount then
-           -- LIMIT maxRows + 1 so we can determine below that maxRows was surpassed
-           QueryBuilder.limitedQuery countQuery ((+ 1) <$> configDbMaxRows)
-         else
-           countQuery
-        )
-        (shouldCount preferCount)
-        iAcceptMediaType
-        wrResAgg
-        configDbPreparedStatements
-  failNotSingular iAcceptMediaType resultSet
-  optionalRollback conf apiReq
-  resultSetWTotal conf apiReq resultSet countQuery
-
-resultSetWTotal :: AppConfig -> ApiRequest -> ResultSet -> SQL.Snippet -> DbHandler ResultSet
-resultSetWTotal _ _ rs@RSPlan{} _ = return rs
-resultSetWTotal AppConfig{..} ApiRequest{iPreferences=Preferences{..}} rs@RSStandard{rsTableTotal=tableTotal} countQuery =
-  case preferCount of
-    Just PlannedCount -> do
-      total <- explain
-      return rs{rsTableTotal=total}
-    Just EstimatedCount ->
-      if tableTotal > (fromIntegral <$> configDbMaxRows) then do
-        total <- max tableTotal <$> explain
-        return rs{rsTableTotal=total}
-      else
-        return rs
-    Just ExactCount ->
-      return rs
-    Nothing ->
-      return rs
-  where
-    explain =
-      lift . SQL.statement mempty . Statements.preparePlanRows countQuery $
-        configDbPreparedStatements
-
-createQuery :: MutateReadPlan -> ApiRequest -> AppConfig -> DbHandler ResultSet
-createQuery mrPlan apiReq@ApiRequest{..} conf = do
-  resultSet <- writeQuery mrPlan apiReq conf
-  failNotSingular iAcceptMediaType resultSet
-  optionalRollback conf apiReq
-  pure resultSet
-
-updateQuery :: MutateReadPlan -> ApiRequest -> AppConfig -> DbHandler ResultSet
-updateQuery mrPlan apiReq@ApiRequest{..} conf = do
-  resultSet <- writeQuery mrPlan apiReq conf
-  failNotSingular iAcceptMediaType resultSet
-  failsChangesOffLimits (RangeQuery.rangeLimit iTopLevelRange) resultSet
-  optionalRollback conf apiReq
-  pure resultSet
-
-singleUpsertQuery :: MutateReadPlan -> ApiRequest -> AppConfig -> DbHandler ResultSet
-singleUpsertQuery mrPlan apiReq conf = do
-  resultSet <- writeQuery mrPlan apiReq conf
-  failPut resultSet
-  optionalRollback conf apiReq
-  pure resultSet
-
-- Makes sure the querystring pk matches the payload pk
-- e.g. PUT /items?id=eq.1 { "id" : 1, .. } is accepted,
-- PUT /items?id=eq.14 { "id" : 2, .. } is rejected.
-- If this condition is not satisfied then nothing is inserted,
-- check the WHERE for INSERT in QueryBuilder.hs to see how it's done
-failPut :: ResultSet -> DbHandler ()
-failPut RSPlan{} = pure ()
-failPut RSStandard{rsQueryTotal=queryTotal} =
-  when (queryTotal /= 1) $ do
-    lift SQL.condemn
-    throwError Error.PutMatchingPkError
-
-deleteQuery :: MutateReadPlan -> ApiRequest -> AppConfig -> DbHandler ResultSet
-deleteQuery mrPlan apiReq@ApiRequest{..} conf = do
-  resultSet <- writeQuery mrPlan apiReq conf
-  failNotSingular iAcceptMediaType resultSet
-  failsChangesOffLimits (RangeQuery.rangeLimit iTopLevelRange) resultSet
-  optionalRollback conf apiReq
-  pure resultSet
-
-invokeQuery :: Routine -> CallReadPlan -> ApiRequest -> AppConfig -> PgVersion -> DbHandler ResultSet
-invokeQuery rout CallReadPlan{crReadPlan, crCallPlan, crResAgg} apiReq@ApiRequest{iPreferences=Preferences{..}, ..} conf@AppConfig{..} pgVer = do
-  resultSet <-
-    lift . SQL.statement mempty $
-      Statements.prepareCall
-        rout
-        (QueryBuilder.callPlanToQuery crCallPlan pgVer)
-        (QueryBuilder.readPlanToQuery crReadPlan)
-        (QueryBuilder.readPlanToCountQuery crReadPlan)
-        (shouldCount preferCount)
-        iAcceptMediaType
-        crResAgg
-        configDbPreparedStatements
-
-  optionalRollback conf apiReq
-  failNotSingular iAcceptMediaType resultSet
-  pure resultSet
-
-openApiQuery :: SchemaCache -> PgVersion -> AppConfig -> Schema -> DbHandler (Maybe (TablesMap, RoutineMap, Maybe Text))
-openApiQuery sCache pgVer AppConfig{..} tSchema =
-  lift $ case configOpenApiMode of
-    OAFollowPriv -> do
-      tableAccess <- SQL.statement [tSchema] (SchemaCache.accessibleTables pgVer configDbPreparedStatements)
-      Just <$> ((,,)
-            (HM.filterWithKey (\qi _ -> S.member qi tableAccess) $ SchemaCache.dbTables sCache)
-        <$> SQL.statement tSchema (SchemaCache.accessibleFuncs pgVer configDbPreparedStatements)
-        <*> SQL.statement tSchema (SchemaCache.schemaDescription configDbPreparedStatements))
-    OAIgnorePriv ->
-      Just <$> ((,,)
-            (HM.filterWithKey (\(QualifiedIdentifier sch _) _ ->  sch == tSchema) $ SchemaCache.dbTables sCache)
-            (HM.filterWithKey (\(QualifiedIdentifier sch _) _ ->  sch == tSchema) $ SchemaCache.dbRoutines sCache)
-        <$> SQL.statement tSchema (SchemaCache.schemaDescription configDbPreparedStatements))
-    OADisabled ->
-      pure Nothing
-
-writeQuery :: MutateReadPlan -> ApiRequest -> AppConfig  -> DbHandler ResultSet
-writeQuery MutateReadPlan{mrReadPlan, mrMutatePlan, mrResAgg} apiReq@ApiRequest{iPreferences=Preferences{..}} conf =
-  let
-    (isInsert, pkCols) = case mrMutatePlan of {Insert{insPkCols} -> (True, insPkCols); _ -> (False, mempty);}
-  in
-  lift . SQL.statement mempty $
-    Statements.prepareWrite
-      (QueryBuilder.readPlanToQuery mrReadPlan)
-      (QueryBuilder.mutatePlanToQuery mrMutatePlan)
-      isInsert
-      (iAcceptMediaType apiReq)
-      mrResAgg
-      preferRepresentation
-      pkCols
-      (configDbPreparedStatements conf)
-
-- |
-- Fail a response if a single JSON object was requested and not exactly one
-- was found.
-failNotSingular :: MediaType -> ResultSet -> DbHandler ()
-failNotSingular _ RSPlan{} = pure ()
-failNotSingular mediaType RSStandard{rsQueryTotal=queryTotal} =
-  when (elem mediaType [MTSingularJSON True,MTSingularJSON False]  && queryTotal /= 1) $ do
-    lift SQL.condemn
-    throwError $ Error.singularityError queryTotal
-
-failsChangesOffLimits :: Maybe Integer -> ResultSet -> DbHandler ()
-failsChangesOffLimits _ RSPlan{} = pure ()
-failsChangesOffLimits Nothing _  = pure ()
-failsChangesOffLimits (Just maxChanges) RSStandard{rsQueryTotal=queryTotal} =
-  when (queryTotal > fromIntegral maxChanges) $ do
-    lift SQL.condemn
-    throwError $ Error.OffLimitsChangesError queryTotal maxChanges
-
-- | Set a transaction to roll back if requested
-optionalRollback :: AppConfig -> ApiRequest -> DbHandler ()
-optionalRollback AppConfig{..} ApiRequest{iPreferences=Preferences{..}} = do
-  lift $ when (shouldRollback || (configDbTxRollbackAll && not shouldCommit)) $ do
-    SQL.sql "SET CONSTRAINTS ALL IMMEDIATE"
-    SQL.condemn
-  where
-    shouldCommit =
-      preferTransaction == Just Commit
-    shouldRollback =
-      preferTransaction == Just Rollback
-
-- | Runs local (transaction scoped) GUCs for every request.
-setPgLocals :: AppConfig  -> KM.KeyMap JSON.Value -> BS.ByteString -> [(ByteString, ByteString)] ->
-               ApiRequest -> PgVersion -> DbHandler ()
-setPgLocals AppConfig{..} claims role roleSettings req actualPgVersion = lift $
-  SQL.statement mempty $ SQL.dynamicallyParameterized
-    ("select " <> intercalateSnippet ", " (searchPathSql : roleSql ++ roleSettingsSql ++ claimsSql ++ [methodSql, pathSql] ++ headersSql ++ cookiesSql ++ appSettingsSql))
-    HD.noResult configDbPreparedStatements
-  where
-    methodSql = setConfigLocal mempty ("request.method", iMethod req)
-    pathSql = setConfigLocal mempty ("request.path", iPath req)
-    headersSql = if usesLegacyGucs
-                   then setConfigLocal "request.header." <$> iHeaders req
-                   else setConfigLocalJson "request.headers" (iHeaders req)
-    cookiesSql = if usesLegacyGucs
-                   then setConfigLocal "request.cookie." <$> iCookies req
-                   else setConfigLocalJson "request.cookies" (iCookies req)
-    claimsSql = if usesLegacyGucs
-                  then setConfigLocal "request.jwt.claim." <$> [(toUtf8 $ K.toText c, toUtf8 $ unquoted v) | (c,v) <- KM.toList claims]
-                  else [setConfigLocal mempty ("request.jwt.claims", LBS.toStrict $ JSON.encode claims)]
-    roleSql = [setConfigLocal mempty ("role", role)]
-    roleSettingsSql = setConfigLocal mempty <$> roleSettings
-    appSettingsSql = setConfigLocal mempty <$> (join bimap toUtf8 <$> configAppSettings)
-    searchPathSql =
-      let schemas = escapeIdentList (iSchema req : configDbExtraSearchPath) in
-      setConfigLocal mempty ("search_path", schemas)
-    usesLegacyGucs = configDbUseLegacyGucs && actualPgVersion < pgVersion140
-
-    unquoted :: JSON.Value -> Text
-    unquoted (JSON.String t) = t
-    unquoted (JSON.Number n) =
-      toS $ formatScientific Fixed (if isInteger n then Just 0 else Nothing) n
-    unquoted (JSON.Bool b) = show b
-    unquoted v = T.decodeUtf8 . LBS.toStrict $ JSON.encode v
-
-- | Runs the pre-request function.
-runPreReq :: AppConfig -> DbHandler ()
-runPreReq conf = lift $ traverse_ (SQL.statement mempty . stmt) (configDbPreRequest conf)
-  where
-    stmt req = SQL.dynamicallyParameterized
-      ("select " <> fromQi req <> "()")
-      HD.noResult
-      (configDbPreparedStatements conf)
@@ -1,192 +1,179 @@
 {-# LANGUAGE DuplicateRecordFields #-}
-{-# LANGUAGE NamedFieldPuns        #-}
 {-|
 Module      : PostgREST.Query.QueryBuilder
 Description : PostgREST SQL queries generating functions.

 This module provides functions to consume data types that
-represent database queries (e.g. ReadPlanTree, MutatePlan) and SqlFragment
+represent database queries (e.g. ReadRequest, MutateRequest) and SqlFragment
 to produce SqlQuery type outputs.
 -}
 module PostgREST.Query.QueryBuilder
-  ( readPlanToQuery
-  , mutatePlanToQuery
-  , readPlanToCountQuery
-  , callPlanToQuery
+  ( readRequestToQuery
+  , mutateRequestToQuery
+  , readRequestToCountQuery
+  , requestToCallProcQuery
  , limitedQuery
  ) where

 import qualified Data.ByteString.Char8           as BS
+import qualified Data.Set                        as S
 import qualified Hasql.DynamicStatements.Snippet as SQL

 import Data.Tree (Tree (..))

-import PostgREST.ApiRequest.Preferences   (PreferResolution (..))
-import PostgREST.Config.PgVersion         (PgVersion, pgVersion110,
-                                           pgVersion130)
-import PostgREST.SchemaCache.Identifiers  (QualifiedIdentifier (..))
-import PostgREST.SchemaCache.Relationship (Cardinality (..),
-                                           Junction (..),
-                                           Relationship (..),
-                                           relIsToOne)
-import PostgREST.SchemaCache.Routine      (RoutineParam (..))
+import PostgREST.DbStructure.Identifiers  (QualifiedIdentifier (..))
+import PostgREST.DbStructure.Proc         (ProcParam (..))
+import PostgREST.DbStructure.Relationship (Cardinality (..),
+                                           Relationship (..))
+import PostgREST.DbStructure.Table        (Table (..))
+import PostgREST.Request.Preferences      (PreferResolution (..))

-import PostgREST.ApiRequest.Types
-import PostgREST.Plan.CallPlan
-import PostgREST.Plan.MutatePlan
-import PostgREST.Plan.ReadPlan
-import PostgREST.Plan.Types
 import PostgREST.Query.SqlFragment
-import PostgREST.RangeQuery        (allRange)
+import PostgREST.Request.Types

 import Protolude

-readPlanToQuery :: ReadPlanTree -> SQL.Snippet
-readPlanToQuery (Node ReadPlan{select,from=mainQi,fromAlias,where_=logicForest,order, range_=readRange, relToParent, relJoinConds} forest) =
+readRequestToQuery :: ReadRequest -> SQL.Snippet
+readRequestToQuery (Node (Select colSelects mainQi tblAlias implJoins logicForest joinConditions_ ordts range, _) forest) =
  "SELECT " <>
-  intercalateSnippet ", " ((pgFmtSelectItem qi <$> (if null select && null forest then defSelect else select)) ++ selects) <> " " <>
-  fromFrag <> " " <>
+  intercalateSnippet ", " ((pgFmtSelectItem qi <$> colSelects) ++ selects) <>
+  "FROM " <> SQL.sql (BS.intercalate ", " (tabl : implJs)) <> " " <>
  intercalateSnippet " " joins <> " " <>
-  (if null logicForest && null relJoinConds
-    then mempty
-    else "WHERE " <> intercalateSnippet " AND " (map (pgFmtLogicTree qi) logicForest ++ map pgFmtJoinCondition relJoinConds)) <> " " <>
-  orderF qi order <> " " <>
-  limitOffsetF readRange
+  (if null logicForest && null joinConditions_ then mempty else "WHERE " <> intercalateSnippet " AND " (map (pgFmtLogicTree qi) logicForest ++ map pgFmtJoinCondition joinConditions_))
+  <> " " <>
+  (if null ordts then mempty else "ORDER BY " <> intercalateSnippet ", " (map (pgFmtOrderTerm qi) ordts)) <> " " <>
+  limitOffsetF range
  where
-    fromFrag = fromF relToParent mainQi fromAlias
-    qi = getQualifiedIdentifier relToParent mainQi fromAlias
-    defSelect = [(unknownField "*" [], Nothing, Nothing)] -- gets all the columns in case of an empty select, ignoring/obtaining these columns is done at the aggregation stage
-    (selects, joins) = foldr getSelectsJoins ([],[]) forest
+    implJs = fromQi <$> implJoins
+    tabl = fromQi mainQi <> maybe mempty (\a -> " AS " <> pgFmtIdent a) tblAlias
+    qi = maybe mainQi (QualifiedIdentifier mempty) tblAlias
+    (joins, selects) = foldr getJoinsSelects ([],[]) forest

-getSelectsJoins :: ReadPlanTree -> ([SQL.Snippet], [SQL.Snippet]) -> ([SQL.Snippet], [SQL.Snippet])
-getSelectsJoins (Node ReadPlan{relToParent=Nothing} _) _ = ([], [])
-getSelectsJoins rr@(Node ReadPlan{select, relName, relToParent=Just rel, relAggAlias, relAlias, relJoinType, relIsSpread} forest) (selects,joins) =
-  let
-    subquery = readPlanToQuery rr
-    aliasOrName = pgFmtIdent $ fromMaybe relName relAlias
-    aggAlias = pgFmtIdent relAggAlias
-    correlatedSubquery sub al cond =
-      (if relJoinType == Just JTInner then "INNER" else "LEFT") <> " JOIN LATERAL ( " <> sub <> " ) AS " <> al <> " ON " <> cond
-    (sel, joi) = if relIsToOne rel
-      then
-        ( if relIsSpread
-            then aggAlias <> ".*"
-            else "row_to_json(" <> aggAlias <> ".*) AS " <> aliasOrName
-        , correlatedSubquery subquery aggAlias "TRUE")
-      else
-        ( "COALESCE( " <> aggAlias <> "." <> aggAlias <> ", '[]') AS " <> aliasOrName
-        , correlatedSubquery (
-            "SELECT json_agg(" <> aggAlias <> ") AS " <> aggAlias <>
-            "FROM (" <> subquery <> " ) AS " <> aggAlias
-          ) aggAlias $ if relJoinType == Just JTInner then aggAlias <> " IS NOT NULL" else "TRUE")
-  in
-  (if null select && null forest then selects else sel:selects, joi:joins)
+getJoinsSelects :: ReadRequest -> ([SQL.Snippet], [SQL.Snippet]) -> ([SQL.Snippet], [SQL.Snippet])
+getJoinsSelects rr@(Node (_, (name, Just Relationship{relCardinality=card,relTable=Table{tableName=table}}, alias, _, joinType, _)) _) (joins,selects) =
+  let subquery = readRequestToQuery rr in
+  case card of
+    M2O _ ->
+      let aliasOrName = fromMaybe name alias
+          localTableName = pgFmtIdent $ table <> "_" <> aliasOrName
+          sel = SQL.sql ("row_to_json(" <> localTableName <> ".*) AS " <> pgFmtIdent aliasOrName)
+          joi = (if joinType == Just JTInner then " INNER" else " LEFT")
+            <> " JOIN LATERAL( " <> subquery <> " ) AS " <> SQL.sql localTableName <> " ON TRUE " in
+      (joi:joins,sel:selects)
+    _ -> case joinType of
+      Just JTInner ->
+        let aliasOrName = fromMaybe name alias
+            locTblName = table <> "_" <> aliasOrName
+            localTableName = pgFmtIdent locTblName
+            internalTableName = pgFmtIdent $ "_" <> locTblName
+            sel = SQL.sql $ localTableName <> "." <> internalTableName <> " AS " <> pgFmtIdent aliasOrName
+            joi = "INNER JOIN LATERAL(" <>
+                    "SELECT json_agg(" <> SQL.sql internalTableName <> ") AS " <> SQL.sql internalTableName <>
+                    "FROM (" <> subquery <> " ) AS " <> SQL.sql internalTableName <>
+                  ") AS " <> SQL.sql localTableName <> " ON " <> SQL.sql localTableName <> "IS NOT NULL" in
+        (joi:joins,sel:selects)
+      _ ->
+        let sel = "COALESCE (("
+               <> "SELECT json_agg(" <> SQL.sql (pgFmtIdent table) <> ".*) "
+               <> "FROM (" <> subquery <> ") " <> SQL.sql (pgFmtIdent table) <> " "
+               <> "), '[]') AS " <> SQL.sql (pgFmtIdent (fromMaybe name alias)) in
+        (joins,sel:selects)
+getJoinsSelects (Node (_, (_, Nothing, _, _, _, _)) _) _ = ([], [])

-mutatePlanToQuery :: MutatePlan -> SQL.Snippet
-mutatePlanToQuery (Insert mainQi iCols body onConflct putConditions returnings _ applyDefaults) =
-  "INSERT INTO " <> fromQi mainQi <> (if null iCols then " " else "(" <> cols <> ") ") <>
-  fromJsonBodyF body iCols True False applyDefaults <>
+mutateRequestToQuery :: MutateRequest -> SQL.Snippet
+mutateRequestToQuery (Insert mainQi iCols body onConflct putConditions returnings) =
+  "WITH " <> normalizedBody body <> " " <>
+  "INSERT INTO " <> SQL.sql (fromQi mainQi) <> SQL.sql (if S.null iCols then " " else "(" <> cols <> ") ") <>
+  "SELECT " <> SQL.sql cols <> " " <>
+  SQL.sql ("FROM json_populate_recordset (null::" <> fromQi mainQi <> ", " <> selectBody <> ") _ ") <>
  -- Only used for PUT
-  (if null putConditions then mempty else "WHERE " <> intercalateSnippet " AND " (pgFmtLogicTree (QualifiedIdentifier mempty "pgrst_body") <$> putConditions)) <>
-  maybe mempty (\(oncDo, oncCols) ->
-    if null oncCols then
-      mempty
-    else
-      " ON CONFLICT(" <> intercalateSnippet ", " (pgFmtIdent <$> oncCols) <> ") " <> case oncDo of
-      IgnoreDuplicates ->
-        "DO NOTHING"
-      MergeDuplicates  ->
-        if null iCols
-           then "DO NOTHING"
-           else "DO UPDATE SET " <> intercalateSnippet ", " ((pgFmtIdent . cfName) <> const " = EXCLUDED." <> (pgFmtIdent . cfName) <$> iCols)
-    ) onConflct <> " " <>
-  returningF mainQi returnings
+  (if null putConditions then mempty else "WHERE " <> intercalateSnippet " AND " (pgFmtLogicTree (QualifiedIdentifier mempty "_") <$> putConditions)) <>
+  SQL.sql (BS.unwords [
+    maybe "" (\(oncDo, oncCols) ->
+      if null oncCols then
+        mempty
+      else
+        "ON CONFLICT(" <> BS.intercalate ", " (pgFmtIdent <$> oncCols) <> ") " <> case oncDo of
+        IgnoreDuplicates ->
+          "DO NOTHING"
+        MergeDuplicates  ->
+          if S.null iCols
+             then "DO NOTHING"
+             else "DO UPDATE SET " <> BS.intercalate ", " (pgFmtIdent <> const " = EXCLUDED." <> pgFmtIdent <$> S.toList iCols)
+      ) onConflct,
+    returningF mainQi returnings
+    ])
  where
-    cols = intercalateSnippet ", " $ pgFmtIdent . cfName <$> iCols
-
-- An update without a limit is always filtered with a WHERE
-mutatePlanToQuery (Update mainQi uCols body logicForest range ordts returnings applyDefaults)
-  | null uCols =
+    cols = BS.intercalate ", " $ pgFmtIdent <$> S.toList iCols
+mutateRequestToQuery (Update mainQi uCols body logicForest returnings) =
+  if S.null uCols
    -- if there are no columns we cannot do UPDATE table SET {empty}, it'd be invalid syntax
    -- selecting an empty resultset from mainQi gives us the column names to prevent errors when using &select=
    -- the select has to be based on "returnings" to make computed overloaded functions not throw
-    "SELECT " <> emptyBodyReturnedColumns <> " FROM " <> fromQi mainQi <> " WHERE false"
-
-  | range == allRange =
-    "UPDATE " <> mainTbl <> " SET " <> nonRangeCols <> " " <>
-    fromJsonBodyF body uCols False False applyDefaults <>
-    whereLogic <> " " <>
-    returningF mainQi returnings
-
-  | otherwise =
-    "WITH " <>
-    "pgrst_update_body AS (" <> fromJsonBodyF body uCols True True applyDefaults <> "), " <>
-    "pgrst_affected_rows AS (" <>
-      "SELECT " <> rangeIdF <> " FROM " <> mainTbl <>
-      whereLogic <> " " <>
-      orderF mainQi ordts <> " " <>
-      limitOffsetF range <>
-    ") " <>
-    "UPDATE " <> mainTbl <> " SET " <> rangeCols <>
-    "FROM pgrst_affected_rows " <>
-    "WHERE " <> whereRangeIdF <> " " <>
-    returningF mainQi returnings
-
+    then SQL.sql ("SELECT " <> emptyBodyReturnedColumns <> " FROM " <> fromQi mainQi <> " WHERE false")
+    else
+      "WITH " <> normalizedBody body <> " " <>
+      "UPDATE " <> SQL.sql (fromQi mainQi) <> " SET " <> SQL.sql cols <> " " <>
+      "FROM (SELECT * FROM json_populate_recordset (null::" <> SQL.sql (fromQi mainQi) <> " , " <> SQL.sql selectBody <> " )) _ " <>
+      (if null logicForest then mempty else "WHERE " <> intercalateSnippet " AND " (pgFmtLogicTree mainQi <$> logicForest)) <> " " <>
+      SQL.sql (returningF mainQi returnings)
  where
-    whereLogic = if null logicForest then mempty else " WHERE " <> intercalateSnippet " AND " (pgFmtLogicTree mainQi <$> logicForest)
-    mainTbl = fromQi mainQi
-    emptyBodyReturnedColumns = if null returnings then "NULL" else intercalateSnippet ", " (pgFmtColumn (QualifiedIdentifier mempty $ qiName mainQi) <$> returnings)
-    nonRangeCols = intercalateSnippet ", " (pgFmtIdent . cfName <> const " = " <> pgFmtColumn (QualifiedIdentifier mempty "pgrst_body") . cfName <$> uCols)
-    rangeCols = intercalateSnippet ", " ((\col -> pgFmtIdent (cfName col) <> " = (SELECT " <> pgFmtIdent (cfName col) <> " FROM pgrst_update_body) ") <$> uCols)
-    (whereRangeIdF, rangeIdF) = mutRangeF mainQi (cfName . coField <$> ordts)
-
-mutatePlanToQuery (Delete mainQi logicForest range ordts returnings)
-  | range == allRange =
-    "DELETE FROM " <> fromQi mainQi <> " " <>
-    whereLogic <> " " <>
-    returningF mainQi returnings
-
-  | otherwise =
-    "WITH " <>
-    "pgrst_affected_rows AS (" <>
-      "SELECT " <> rangeIdF <> " FROM " <> fromQi mainQi <>
-       whereLogic <> " " <>
-      orderF mainQi ordts <> " " <>
-      limitOffsetF range <>
-    ") " <>
-    "DELETE FROM " <> fromQi mainQi <> " " <>
-    "USING pgrst_affected_rows " <>
-    "WHERE " <> whereRangeIdF <> " " <>
-    returningF mainQi returnings
+    cols = BS.intercalate ", " (pgFmtIdent <> const " = _." <> pgFmtIdent <$> S.toList uCols)
+    emptyBodyReturnedColumns :: SqlFragment
+    emptyBodyReturnedColumns
+      | null returnings = "NULL"
+      | otherwise       = BS.intercalate ", " (pgFmtColumn (QualifiedIdentifier mempty $ qiName mainQi) <$> returnings)
+mutateRequestToQuery (Delete mainQi logicForest returnings) =
+  "DELETE FROM " <> SQL.sql (fromQi mainQi) <> " " <>
+  (if null logicForest then mempty else "WHERE " <> intercalateSnippet " AND " (map (pgFmtLogicTree mainQi) logicForest)) <> " " <>
+  SQL.sql (returningF mainQi returnings)

+requestToCallProcQuery :: CallRequest -> SQL.Snippet
+requestToCallProcQuery (FunctionCall qi params args returnsScalar multipleCall returnings) =
+  prmsCTE <> argsBody
  where
-    whereLogic = if null logicForest then mempty else " WHERE " <> intercalateSnippet " AND " (pgFmtLogicTree mainQi <$> logicForest)
-    (whereRangeIdF, rangeIdF) = mutRangeF mainQi (cfName . coField <$> ordts)
+    (prmsCTE, argFrag) = case params of
+      OnePosParam prm -> ("WITH pgrst_args AS (SELECT NULL)", singleParameter args (encodeUtf8 $ ppType prm))
+      KeyParams []    -> (mempty, mempty)
+      KeyParams prms  -> (
+          "WITH " <> normalizedBody args <> ", " <>
+          SQL.sql (
+            BS.unwords [
+            "pgrst_args AS (",
+              "SELECT * FROM json_to_recordset(" <> selectBody <> ") AS _(" <> fmtParams prms (const mempty) (\a -> " " <> encodeUtf8 (ppType a)) <> ")",
+            ")"])
+         , SQL.sql $ if multipleCall
+             then fmtParams prms varadicPrefix (\a -> " := pgrst_args." <> pgFmtIdent (ppName a))
+             else fmtParams prms varadicPrefix (\a -> " := (SELECT " <> pgFmtIdent (ppName a) <> " FROM pgrst_args LIMIT 1)")
+        )

-callPlanToQuery :: CallPlan -> PgVersion -> SQL.Snippet
-callPlanToQuery (FunctionCall qi params args returnsScalar returnsSetOfScalar returnsCompositeAlias returnings) pgVer =
-  "SELECT " <> (if returnsScalar || returnsSetOfScalar then "pgrst_call.pgrst_scalar" else returnedColumns) <> " " <>
-  fromCall
-  where
-    fromCall = case params of
-      OnePosParam prm -> "FROM " <> callIt (singleParameter args $ encodeUtf8 $ ppType prm)
-      KeyParams []    -> "FROM " <> callIt mempty
-      KeyParams prms  -> fromJsonBodyF args ((\p -> CoercibleField (ppName p) mempty False (ppTypeMaxLength p) Nothing Nothing) <$> prms) False True False <> ", " <>
-                         "LATERAL " <> callIt (fmtParams prms)
+    fmtParams :: [ProcParam] -> (ProcParam -> SqlFragment) -> (ProcParam -> SqlFragment) -> SqlFragment
+    fmtParams prms prmFragPre prmFragSuf = BS.intercalate ", "
+      ((\a -> prmFragPre a <> pgFmtIdent (ppName a) <> prmFragSuf a) <$> prms)

-    callIt :: SQL.Snippet -> SQL.Snippet
-    callIt argument | pgVer < pgVersion130 && pgVer >= pgVersion110 && returnsCompositeAlias = "(SELECT (" <> fromQi qi <> "(" <> argument <> ")).*) pgrst_call"
-                    | returnsScalar || returnsSetOfScalar                                    = "(SELECT " <> fromQi qi <> "(" <> argument <> ") pgrst_scalar) pgrst_call"
-                    | otherwise                                                              = fromQi qi <> "(" <> argument <> ") pgrst_call"
+    varadicPrefix :: ProcParam -> SqlFragment
+    varadicPrefix a = if ppVar a then "VARIADIC " else mempty

-    fmtParams :: [RoutineParam] -> SQL.Snippet
-    fmtParams prms = intercalateSnippet ", "
-      ((\a -> (if ppVar a then "VARIADIC " else mempty) <> pgFmtIdent (ppName a) <> " := pgrst_body." <> pgFmtIdent (ppName a)) <$> prms)
+    argsBody :: SQL.Snippet
+    argsBody
+      | multipleCall =
+          if returnsScalar
+            then "SELECT " <> callIt <> " AS pgrst_scalar FROM pgrst_args"
+            else "SELECT pgrst_lat_args.* FROM pgrst_args, " <>
+                 "LATERAL ( SELECT " <> returnedColumns <> " FROM " <> callIt <> " ) pgrst_lat_args"
+      | otherwise =
+          if returnsScalar
+            then "SELECT " <> callIt <> " AS pgrst_scalar"
+            else "SELECT " <> returnedColumns <> " FROM " <> callIt
+
+    callIt :: SQL.Snippet
+    callIt = SQL.sql (fromQi qi) <> "(" <> argFrag <> ")"

    returnedColumns :: SQL.Snippet
    returnedColumns
      | null returnings = "*"
-      | otherwise       = intercalateSnippet ", " (pgFmtColumn (QualifiedIdentifier mempty "pgrst_call") <$> returnings)
+      | otherwise       = SQL.sql $ BS.intercalate ", " (pgFmtColumn (QualifiedIdentifier mempty $ qiName qi) <$> returnings)
+

 -- | SQL query meant for COUNTing the root node of the Tree.
 -- It only takes WHERE into account and doesn't include LIMIT/OFFSET because it would reduce the COUNT.
@@ -196,57 +183,24 @@ callPlanToQuery (FunctionCall qi params args returnsScalar returnsSetOfScalar re
 -- For this case, we use a WHERE EXISTS instead of an INNER JOIN on the count query.
 -- See https://github.com/PostgREST/postgrest/issues/2009#issuecomment-977473031
 -- Only for the nodes that have an INNER JOIN linked to the root level.
-readPlanToCountQuery :: ReadPlanTree -> SQL.Snippet
-readPlanToCountQuery (Node ReadPlan{from=mainQi, fromAlias=tblAlias, where_=logicForest, relToParent=rel, relJoinConds} forest) =
-  "SELECT 1 " <> fromFrag <>
-  (if null logicForest && null relJoinConds && null subQueries
+readRequestToCountQuery :: ReadRequest -> SQL.Snippet
+readRequestToCountQuery (Node (Select{from=qi, implicitJoins=implJoins, where_=logicForest, joinConditions=joinConditions_}, _) forest) =
+  "SELECT 1 FROM " <> SQL.sql (BS.intercalate ", " (fromQi qi:(fromQi <$> implJoins))) <>
+  (if null logicForest && null joinConditions_ && null subQueries
    then mempty
    else " WHERE " ) <>
  intercalateSnippet " AND " (
-    map (pgFmtLogicTreeCount qi) logicForest ++
-    map pgFmtJoinCondition relJoinConds ++
+    map (pgFmtLogicTree qi) logicForest ++
+    map pgFmtJoinCondition joinConditions_ ++
    subQueries
  )
  where
-    qi = getQualifiedIdentifier rel mainQi tblAlias
-    fromFrag = fromF rel mainQi tblAlias
    subQueries = foldr existsSubquery [] forest
-    existsSubquery :: ReadPlanTree -> [SQL.Snippet] -> [SQL.Snippet]
-    existsSubquery readReq@(Node ReadPlan{relJoinType=joinType} _) rest =
+    existsSubquery :: ReadRequest -> [SQL.Snippet] -> [SQL.Snippet]
+    existsSubquery readReq@(Node (_, (_, _, _, _, joinType, _)) _) rest =
      if joinType == Just JTInner
-        then ("EXISTS (" <> readPlanToCountQuery readReq <> " )"):rest
-        else rest
-    findNullEmbedRel fld = find (\(Node ReadPlan{relAggAlias} _) -> fld == relAggAlias) forest
-
-    -- https://github.com/PostgREST/postgrest/pull/2930#discussion_r1325293698
-    pgFmtLogicTreeCount :: QualifiedIdentifier -> CoercibleLogicTree -> SQL.Snippet
-    pgFmtLogicTreeCount qiCount (CoercibleExpr hasNot op frst) = SQL.sql notOp <> " (" <> intercalateSnippet (opSql op) (pgFmtLogicTreeCount qiCount <$> frst) <> ")"
-      where
-        notOp =  if hasNot then "NOT" else mempty
-        opSql And = " AND "
-        opSql Or  = " OR "
-    pgFmtLogicTreeCount _ (CoercibleStmnt (CoercibleFilterNullEmbed hasNot fld)) =
-      maybe mempty (\x -> (if not hasNot then "NOT " else mempty) <> "EXISTS (" <> readPlanToCountQuery x <> ")") (findNullEmbedRel fld)
-    pgFmtLogicTreeCount qiCount (CoercibleStmnt flt) = pgFmtFilter qiCount flt
+        then ("EXISTS (" <> readRequestToCountQuery readReq <> " )"):rest
+        else mempty

 limitedQuery :: SQL.Snippet -> Maybe Integer -> SQL.Snippet
 limitedQuery query maxRows = query <> SQL.sql (maybe mempty (\x -> " LIMIT " <> BS.pack (show x)) maxRows)
-
-- TODO refactor so this function is uneeded and ComputedRelationship QualifiedIdentifier comes from the ReadPlan type
-getQualifiedIdentifier :: Maybe Relationship -> QualifiedIdentifier -> Maybe Alias -> QualifiedIdentifier
-getQualifiedIdentifier rel mainQi tblAlias = case rel of
-  Just ComputedRelationship{relFunction} -> QualifiedIdentifier mempty $ fromMaybe (qiName relFunction) tblAlias
-  _                                      -> maybe mainQi (QualifiedIdentifier mempty) tblAlias
-
-- FROM clause plus implicit joins
-fromF :: Maybe Relationship -> QualifiedIdentifier -> Maybe Alias -> SQL.Snippet
-fromF rel mainQi tblAlias = "FROM " <>
-  (case rel of
-    -- Due to the use of CTEs on RPC, we need to cast the parameter to the table name in case of function overloading.
-    -- See https://github.com/PostgREST/postgrest/issues/2963#issuecomment-1736557386
-    Just ComputedRelationship{relFunction,relTableAlias,relTable} -> fromQi relFunction <> "(" <> pgFmtIdent (qiName relTableAlias) <> "::" <> fromQi relTable <> ")"
-    _                                                             -> fromQi mainQi) <>
-  maybe mempty (\a -> " AS " <> pgFmtIdent a) tblAlias <>
-  (case rel of
-    Just Relationship{relCardinality=M2M Junction{junTable=jt}} -> ", " <> fromQi jt
-    _                                                           -> mempty)
@@ -1,129 +1,127 @@
-{-# LANGUAGE LambdaCase     #-}
-{-# LANGUAGE NamedFieldPuns #-}
-{-# LANGUAGE QuasiQuotes    #-}
+{-# LANGUAGE LambdaCase  #-}
+{-# LANGUAGE QuasiQuotes #-}
 {-|
 Module      : PostgREST.Query.SqlFragment
 Description : Helper functions for PostgREST.QueryBuilder.
+
+Any function that outputs a SqlFragment should be in this module.
 -}
 module PostgREST.Query.SqlFragment
  ( noLocationF
-  , aggF
+  , SqlFragment
+  , asBinaryF
+  , asCsvF
+  , asJsonF
+  , asJsonSingleF
  , countF
  , fromQi
+  , ftsOperators
  , limitOffsetF
  , locationF
-  , mutRangeF
-  , orderF
+  , normalizedBody
+  , operators
  , pgFmtColumn
-  , pgFmtFilter
  , pgFmtIdent
  , pgFmtJoinCondition
  , pgFmtLogicTree
  , pgFmtOrderTerm
  , pgFmtSelectItem
-  , fromJsonBodyF
  , responseHeadersF
  , responseStatusF
  , returningF
+  , selectBody
  , singleParameter
-  , sourceCTE
  , sourceCTEName
  , unknownEncoder
  , intercalateSnippet
-  , explainF
-  , setConfigLocal
-  , setConfigLocalJson
-  , escapeIdent
-  , escapeIdentList
  ) where

-import qualified Data.Aeson                      as JSON
 import qualified Data.ByteString.Char8           as BS
 import qualified Data.ByteString.Lazy            as LBS
-import qualified Data.HashMap.Strict             as HM
+import qualified Data.HashMap.Strict             as M
 import qualified Data.Text                       as T
-import qualified Data.Text.Encoding              as T
 import qualified Hasql.DynamicStatements.Snippet as SQL
 import qualified Hasql.Encoders                  as HE

-import Control.Arrow ((***))
-
 import Data.Foldable                 (foldr1)
 import Text.InterpolatedString.Perl6 (qc)

-import PostgREST.ApiRequest.Types        (Alias, Cast,
-                                          FtsOperator (..),
+import PostgREST.DbStructure.Identifiers (FieldName,
+                                          QualifiedIdentifier (..))
+import PostgREST.RangeQuery              (NonnegRange, allRange,
+                                          rangeLimit, rangeOffset)
+import PostgREST.Request.Types           (Alias, Field, Filter (..),
+                                          JoinCondition (..),
                                          JsonOperand (..),
                                          JsonOperation (..),
                                          JsonPath,
                                          LogicOperator (..),
-                                          OpExpr (..),
-                                          OpQuantifier (..),
+                                          LogicTree (..), OpExpr (..),
                                          Operation (..),
                                          OrderDirection (..),
                                          OrderNulls (..),
-                                          QuantOperator (..),
-                                          SimpleOperator (..),
+                                          OrderTerm (..), SelectItem,
                                          TrileanVal (..))
-import PostgREST.MediaType               (MTPlanFormat (..),
-                                          MTPlanOption (..))
-import PostgREST.Plan.ReadPlan           (JoinCondition (..))
-import PostgREST.Plan.Types              (CoercibleField (..),
-                                          CoercibleFilter (..),
-                                          CoercibleLogicTree (..),
-                                          CoercibleOrderTerm (..),
-                                          unknownField)
-import PostgREST.RangeQuery              (NonnegRange, allRange,
-                                          rangeLimit, rangeOffset)
-import PostgREST.SchemaCache.Identifiers (FieldName,
-                                          QualifiedIdentifier (..))
-import PostgREST.SchemaCache.Routine     (ResultAggregate (..),
-                                          Routine (..),
-                                          funcReturnsScalar,
-                                          funcReturnsSetOfScalar,
-                                          funcReturnsSingleComposite)

 import Protolude hiding (cast)

-sourceCTEName :: Text
-sourceCTEName = "pgrst_source"

-sourceCTE :: SQL.Snippet
-sourceCTE = "pgrst_source"
+-- | A part of a SQL query that cannot be executed independently
+type SqlFragment = ByteString

-noLocationF :: SQL.Snippet
+noLocationF :: SqlFragment
 noLocationF = "array[]::text[]"

-simpleOperator :: SimpleOperator -> SQL.Snippet
-simpleOperator = \case
-  OpNotEqual        -> "<>"
-  OpContains        -> "@>"
-  OpContained       -> "<@"
-  OpOverlap         -> "&&"
-  OpStrictlyLeft    -> "<<"
-  OpStrictlyRight   -> ">>"
-  OpNotExtendsRight -> "&<"
-  OpNotExtendsLeft  -> "&>"
-  OpAdjacent        -> "-|-"
+sourceCTEName :: SqlFragment
+sourceCTEName = "pgrst_source"

-quantOperator :: QuantOperator -> SQL.Snippet
-quantOperator = \case
-  OpEqual            -> "="
-  OpGreaterThanEqual -> ">="
-  OpGreaterThan      -> ">"
-  OpLessThanEqual    -> "<="
-  OpLessThan         -> "<"
-  OpLike             -> "like"
-  OpILike            -> "ilike"
-  OpMatch            -> "~"
-  OpIMatch           -> "~*"
+operators :: M.HashMap Text SqlFragment
+operators = M.union (M.fromList [
+  ("eq", "="),
+  ("gte", ">="),
+  ("gt", ">"),
+  ("lte", "<="),
+  ("lt", "<"),
+  ("neq", "<>"),
+  ("like", "LIKE"),
+  ("ilike", "ILIKE"),
+  ("in", "IN"),
+  ("is", "IS"),
+  ("cs", "@>"),
+  ("cd", "<@"),
+  ("ov", "&&"),
+  ("sl", "<<"),
+  ("sr", ">>"),
+  ("nxr", "&<"),
+  ("nxl", "&>"),
+  ("adj", "-|-")]) ftsOperators

-ftsOperator :: FtsOperator -> SQL.Snippet
-ftsOperator = \case
-  FilterFts          -> "@@ to_tsquery"
-  FilterFtsPlain     -> "@@ plainto_tsquery"
-  FilterFtsPhrase    -> "@@ phraseto_tsquery"
-  FilterFtsWebsearch -> "@@ websearch_to_tsquery"
+ftsOperators :: M.HashMap Text SqlFragment
+ftsOperators = M.fromList [
+  ("fts", "@@ to_tsquery"),
+  ("plfts", "@@ plainto_tsquery"),
+  ("phfts", "@@ phraseto_tsquery"),
+  ("wfts", "@@ websearch_to_tsquery")
+  ]
+
+-- |
+-- These CTEs convert a json object into a json array, this way we can use json_populate_recordset for all json payloads
+-- Otherwise we'd have to use json_populate_record for json objects and json_populate_recordset for json arrays
+-- We do this in SQL to avoid processing the JSON in application code
+-- TODO: At this stage there shouldn't be a Maybe since ApiRequest should ensure that an INSERT/UPDATE has a body
+normalizedBody :: Maybe LBS.ByteString -> SQL.Snippet
+normalizedBody body =
+  "pgrst_payload AS (SELECT " <> jsonPlaceHolder <> " AS json_data), " <>
+  SQL.sql (BS.unwords [
+    "pgrst_body AS (",
+      "SELECT",
+        "CASE WHEN json_typeof(json_data) = 'array'",
+          "THEN json_data",
+          "ELSE json_build_array(json_data)",
+        "END AS val",
+      "FROM pgrst_payload)"])
+  where
+    jsonPlaceHolder = SQL.encoderAndParam (HE.nullable HE.unknown) (LBS.toStrict <$> body) <> "::json"

 singleParameter :: Maybe LBS.ByteString -> ByteString -> SQL.Snippet
 singleParameter body typ =
@@ -132,6 +130,9 @@ singleParameter body typ =
    then SQL.encoderAndParam (HE.nullable HE.bytea) (LBS.toStrict <$> body)
    else SQL.encoderAndParam (HE.nullable HE.unknown) (LBS.toStrict <$> body) <> "::" <> SQL.sql typ

+selectBody :: SqlFragment
+selectBody = "(SELECT val FROM pgrst_body)"
+
 -- Here we build the pg array literal, e.g '{"Hebdon, John","Other","Another"}', manually.
 -- This is necessary to pass an "unknown" array and let pg infer the type.
 -- There are backslashes here, but since this value is parametrized and is not a string constant
@@ -146,34 +147,13 @@ pgBuildArrayLiteral vals =
 "{" <> T.intercalate "," (escaped <$> vals) <> "}"

 -- TODO: refactor by following https://github.com/PostgREST/postgrest/pull/1631#issuecomment-711070833
-pgFmtIdent :: Text -> SQL.Snippet
-pgFmtIdent x = SQL.sql $ escapeIdent x
-
-escapeIdent :: Text -> ByteString
-escapeIdent x = encodeUtf8 $ "\"" <> T.replace "\"" "\"\"" (trimNullChars x) <> "\""
-
-- Only use it if the input comes from the database itself, like on `jsonb_build_object('column_from_a_table', val)..`
-pgFmtLit :: Text -> Text
-pgFmtLit x =
-  let trimmed = trimNullChars x
-      escaped = "'" <> T.replace "'" "''" trimmed <> "'"
-      slashed = T.replace "\\" "\\\\" escaped in
-  if "\\" `T.isInfixOf` escaped
-    then "E" <> slashed
-    else slashed
+pgFmtIdent :: Text -> SqlFragment
+pgFmtIdent x = encodeUtf8 $ "\"" <> T.replace "\"" "\"\"" (trimNullChars x) <> "\""

 trimNullChars :: Text -> Text
 trimNullChars = T.takeWhile (/= '\x0')

-- |
-- Format a list of identifiers and separate them by commas.
--
-- >>> escapeIdentList ["schema_1", "schema_2", "SPECIAL \"@/\\#~_-"]
-- "\"schema_1\", \"schema_2\", \"SPECIAL \"\"@/\\#~_-\""
-escapeIdentList :: [Text] -> ByteString
-escapeIdentList schemas = BS.intercalate ", " $ escapeIdent <$> schemas
-
-asCsvF :: SQL.Snippet
+asCsvF :: SqlFragment
 asCsvF = asCsvHeaderF <> " || '\n' || " <> asCsvBodyF
  where
    asCsvHeaderF =
@@ -181,49 +161,26 @@ asCsvF = asCsvHeaderF <> " || '\n' || " <> asCsvBodyF
      "  FROM (" <>
      "    SELECT json_object_keys(r)::text as k" <>
      "    FROM ( " <>
-      "      SELECT row_to_json(hh) as r from " <> sourceCTE <> " as hh limit 1" <>
+      "      SELECT row_to_json(hh) as r from " <> sourceCTEName <> " as hh limit 1" <>
      "    ) s" <>
      "  ) a" <>
      ")"
    asCsvBodyF = "coalesce(string_agg(substring(_postgrest_t::text, 2, length(_postgrest_t::text) - 2), '\n'), '')"

-addNullsToSnip :: Bool -> SQL.Snippet -> SQL.Snippet
-addNullsToSnip strip snip =
-  if strip then "json_strip_nulls(" <> snip <> ")" else  snip
+asJsonF :: Bool -> SqlFragment
+asJsonF returnsScalar
+  | returnsScalar = "coalesce(json_agg(_postgrest_t.pgrst_scalar), '[]')::character varying"
+  | otherwise     = "coalesce(json_agg(_postgrest_t), '[]')::character varying"

-asJsonSingleF :: Maybe Routine -> Bool -> SQL.Snippet
-asJsonSingleF rout strip
-  | returnsScalar = "coalesce(" <> addNullsToSnip strip "json_agg(_postgrest_t.pgrst_scalar)->0"  <> ", 'null')"
-  | otherwise     = "coalesce(" <> addNullsToSnip strip "json_agg(_postgrest_t)->0"  <> ", 'null')"
-  where
-    returnsScalar = maybe False funcReturnsScalar rout
+asJsonSingleF :: Bool -> SqlFragment
+asJsonSingleF returnsScalar
+  | returnsScalar = "coalesce((json_agg(_postgrest_t.pgrst_scalar)->0)::text, 'null')"
+  | otherwise     = "coalesce((json_agg(_postgrest_t)->0)::text, 'null')"

-asJsonF :: Maybe Routine -> Bool -> SQL.Snippet
-asJsonF rout strip
-  | returnsSingleComposite    = "coalesce(" <> addNullsToSnip strip "json_agg(_postgrest_t)->0" <> ", 'null')"
-  | returnsScalar             = "coalesce(" <> addNullsToSnip strip "json_agg(_postgrest_t.pgrst_scalar)->0" <> ", 'null')"
-  | returnsSetOfScalar        = "coalesce(" <> addNullsToSnip strip "json_agg(_postgrest_t.pgrst_scalar)" <> ", '[]')"
-  | otherwise                 = "coalesce(" <> addNullsToSnip strip "json_agg(_postgrest_t)" <> ", '[]')"
-  where
-    (returnsSingleComposite, returnsScalar, returnsSetOfScalar) = case rout of
-      Just r  -> (funcReturnsSingleComposite r, funcReturnsScalar r, funcReturnsSetOfScalar r)
-      Nothing -> (False, False, False)
+asBinaryF :: FieldName -> SqlFragment
+asBinaryF fieldName = "coalesce(string_agg(_postgrest_t." <> pgFmtIdent fieldName <> ", ''), '')"

-
-asXmlF :: Maybe FieldName -> SQL.Snippet
-asXmlF (Just fieldName) = "coalesce(xmlagg(_postgrest_t." <> pgFmtIdent fieldName <> "), '')"
-- TODO unreachable because a previous step(binaryField) will validate that there's a field. This will be cleared once custom media types are implemented.
-asXmlF Nothing          = "coalesce(xmlagg(_postgrest_t), '')"
-
-asGeoJsonF ::  SQL.Snippet
-asGeoJsonF = "json_build_object('type', 'FeatureCollection', 'features', coalesce(json_agg(ST_AsGeoJSON(_postgrest_t)::json), '[]'))"
-
-asBinaryF :: Maybe FieldName -> SQL.Snippet
-asBinaryF (Just fieldName) = "coalesce(string_agg(_postgrest_t." <> pgFmtIdent fieldName <> ", ''), '')"
-- TODO unreachable because a previous step(binaryField) will validate that there's a field. This will be cleared once custom media types are implemented.
-asBinaryF Nothing          = "coalesce(string_agg(_postgrest_t, ''), '')"
-
-locationF :: [Text] -> SQL.Snippet
+locationF :: [Text] -> SqlFragment
 locationF pKeys = [qc|(
  WITH data AS (SELECT row_to_json(_) AS row FROM {sourceCTEName} AS _ LIMIT 1)
  SELECT array_agg(json_data.key || '=' || coalesce('eq.' || json_data.value, 'is.null'))
@@ -233,161 +190,85 @@ locationF pKeys = [qc|(
  where
    fmtPKeys = T.intercalate "','" pKeys

-fromQi :: QualifiedIdentifier -> SQL.Snippet
+fromQi :: QualifiedIdentifier -> SqlFragment
 fromQi t = (if T.null s then mempty else pgFmtIdent s <> ".") <> pgFmtIdent n
  where
    n = qiName t
    s = qiSchema t

-pgFmtColumn :: QualifiedIdentifier -> Text -> SQL.Snippet
+pgFmtColumn :: QualifiedIdentifier -> Text -> SqlFragment
 pgFmtColumn table "*" = fromQi table <> ".*"
 pgFmtColumn table c   = fromQi table <> "." <> pgFmtIdent c

-pgFmtCallUnary :: Text -> SQL.Snippet -> SQL.Snippet
-pgFmtCallUnary f x = SQL.sql (encodeUtf8 f) <> "(" <> x <> ")"
+pgFmtField :: QualifiedIdentifier -> Field -> SQL.Snippet
+pgFmtField table (c, jp) = SQL.sql (pgFmtColumn table c) <> pgFmtJsonPath jp

-pgFmtField :: QualifiedIdentifier -> CoercibleField -> SQL.Snippet
-pgFmtField table CoercibleField{cfName=fn, cfJsonPath=[]}                                = pgFmtColumn table fn
-pgFmtField table CoercibleField{cfName=fn, cfToJson=doToJson, cfJsonPath=jp} | doToJson  = "to_jsonb(" <> pgFmtColumn table fn <> ")" <> pgFmtJsonPath jp
-                                                                             | otherwise = pgFmtColumn table fn <> pgFmtJsonPath jp
-
-- Select the value of a named element from a table, applying its optional coercion mapping if any.
-pgFmtTableCoerce :: QualifiedIdentifier -> CoercibleField -> SQL.Snippet
-pgFmtTableCoerce table fld@(CoercibleField{cfTransform=(Just formatterProc)}) = pgFmtCallUnary formatterProc (pgFmtField table fld)
-pgFmtTableCoerce table f = pgFmtField table f
-
-- | Like the previous but now we just have a name so no namespace or JSON paths.
-pgFmtCoerceNamed :: CoercibleField -> SQL.Snippet
-pgFmtCoerceNamed CoercibleField{cfName=fn, cfTransform=(Just formatterProc)} = pgFmtCallUnary formatterProc (pgFmtIdent fn) <> " AS " <> pgFmtIdent fn
-pgFmtCoerceNamed CoercibleField{cfName=fn} = pgFmtIdent fn
-
-pgFmtSelectItem :: QualifiedIdentifier -> (CoercibleField, Maybe Cast, Maybe Alias) -> SQL.Snippet
-pgFmtSelectItem table (fld, Nothing, alias) = pgFmtTableCoerce table fld <> pgFmtAs (cfName fld) (cfJsonPath fld) alias
+pgFmtSelectItem :: QualifiedIdentifier -> SelectItem -> SQL.Snippet
+pgFmtSelectItem table (f@(fName, jp), Nothing, alias, _, _) = pgFmtField table f <> SQL.sql (pgFmtAs fName jp alias)
 -- Ideally we'd quote the cast with "pgFmtIdent cast". However, that would invalidate common casts such as "int", "bigint", etc.
 -- Try doing: `select 1::"bigint"` - it'll err, using "int8" will work though. There's some parser magic that pg does that's invalidated when quoting.
 -- Not quoting should be fine, we validate the input on Parsers.
-pgFmtSelectItem table (fld, Just cast, alias) = "CAST (" <> pgFmtTableCoerce table fld <> " AS " <> SQL.sql (encodeUtf8 cast) <> " )" <> pgFmtAs (cfName fld) (cfJsonPath fld) alias
+pgFmtSelectItem table (f@(fName, jp), Just cast, alias, _, _) = "CAST (" <> pgFmtField table f <> " AS " <> SQL.sql (encodeUtf8 cast) <> " )" <> SQL.sql (pgFmtAs fName jp alias)

-- TODO: At this stage there shouldn't be a Maybe since ApiRequest should ensure that an INSERT/UPDATE has a body
-fromJsonBodyF :: Maybe LBS.ByteString -> [CoercibleField] -> Bool -> Bool -> Bool -> SQL.Snippet
-fromJsonBodyF body fields includeSelect includeLimitOne includeDefaults =
-  (if includeSelect then "SELECT " <> namedCols <> " " else mempty) <>
-  "FROM (SELECT " <> jsonPlaceHolder <> " AS json_data) pgrst_payload, " <>
-  -- convert a json object into a json array, this way we can use json_to_recordset for all json payloads
-  -- Otherwise we'd have to use json_to_record for json objects and json_to_recordset for json arrays
-  -- We do this in SQL to avoid processing the JSON in application code
-  "LATERAL (SELECT CASE WHEN " <> jsonTypeofF <> "(pgrst_payload.json_data) = 'array' THEN pgrst_payload.json_data ELSE " <> jsonBuildArrayF <> "(pgrst_payload.json_data) END AS val) pgrst_uniform_json, " <>
-  (if includeDefaults
-    then "LATERAL (SELECT jsonb_agg(jsonb_build_object(" <> defsJsonb <> ") || elem) AS val from jsonb_array_elements(pgrst_uniform_json.val) elem) pgrst_json_defs, "
-    else mempty) <>
-  "LATERAL (SELECT " <> parsedCols <> " FROM " <>
-    (if null fields
-      -- When we are inserting no columns (e.g. using default values), we can't use our ordinary `json_to_recordset`
-      -- because it can't extract records with no columns (there's no valid syntax for the `AS (colName colType,...)`
-      -- part). But we still need to ensure as many rows are created as there are array elements.
-      then SQL.sql $ jsonArrayElementsF <> "(" <> finalBodyF <> ") _ "
-      else jsonToRecordsetF <> "(" <> SQL.sql finalBodyF <> ") AS _(" <> typedCols <> ") " <> if includeLimitOne then "LIMIT 1" else mempty
-    ) <>
-  ") pgrst_body "
-  where
-    namedCols = intercalateSnippet ", " $ fromQi  . QualifiedIdentifier "pgrst_body" . cfName <$> fields
-    parsedCols = intercalateSnippet ", " $ pgFmtCoerceNamed <$> fields
-    typedCols = intercalateSnippet ", " $ pgFmtIdent . cfName <> const " " <> SQL.sql . encodeUtf8 . cfIRType <$> fields
-    defsJsonb = SQL.sql $ BS.intercalate "," fieldsWDefaults
-    fieldsWDefaults = mapMaybe (\case
-        CoercibleField{cfName=nam, cfDefault=Just def} -> Just $ encodeUtf8 (pgFmtLit nam <> ", " <> def)
-        CoercibleField{cfDefault=Nothing} -> Nothing
-      ) fields
-    (finalBodyF, jsonTypeofF, jsonBuildArrayF, jsonArrayElementsF, jsonToRecordsetF) =
-      if includeDefaults
-        then ("pgrst_json_defs.val", "jsonb_typeof", "jsonb_build_array", "jsonb_array_elements", "jsonb_to_recordset")
-        else ("pgrst_uniform_json.val", "json_typeof", "json_build_array", "json_array_elements", "json_to_recordset")
-    jsonPlaceHolder = SQL.encoderAndParam (HE.nullable $ if includeDefaults then HE.jsonbLazyBytes else HE.jsonLazyBytes) body
-
-pgFmtOrderTerm :: QualifiedIdentifier -> CoercibleOrderTerm -> SQL.Snippet
+pgFmtOrderTerm :: QualifiedIdentifier -> OrderTerm -> SQL.Snippet
 pgFmtOrderTerm qi ot =
-  fmtOTerm ot <> " " <>
+  pgFmtField qi (otTerm ot) <> " " <>
  SQL.sql (BS.unwords [
-    maybe mempty direction $ coDirection ot,
-    maybe mempty nullOrder $ coNullOrder ot])
+    maybe mempty direction $ otDirection ot,
+    maybe mempty nullOrder $ otNullOrder ot])
  where
-    fmtOTerm = \case
-      CoercibleOrderTerm{coField=cof}                            -> pgFmtField qi cof
-      CoercibleOrderRelationTerm{coRelation, coRelTerm=(fn, jp)} -> pgFmtField (QualifiedIdentifier mempty coRelation) (unknownField fn jp)
-
    direction OrderAsc  = "ASC"
    direction OrderDesc = "DESC"

    nullOrder OrderNullsFirst = "NULLS FIRST"
    nullOrder OrderNullsLast  = "NULLS LAST"

-- | Interpret a literal in the way the planner indicated through the CoercibleField.
-pgFmtUnknownLiteralForField :: SQL.Snippet -> CoercibleField -> SQL.Snippet
-pgFmtUnknownLiteralForField value CoercibleField{cfTransform=(Just parserProc)} = pgFmtCallUnary parserProc value
-- But when no transform is requested, we just use the literal as-is.
-pgFmtUnknownLiteralForField value _ = value

-- | Array version of the above, used by ANY().
-pgFmtArrayLiteralForField :: [Text] -> CoercibleField -> SQL.Snippet
-- When a transformation is requested, we need to apply the transformation to each element of the array. This could be done by just making a query with `parser(value)` for each value, but may lead to huge query lengths. Imagine `data_representations.color_from_text('...'::text)` for repeated for a hundred values. Instead we use `unnest()` to unpack a standard array literal and then apply the transformation to each element, like a map.
-- Note the literals will be treated as text since in every case when we use ANY() the parameters are textual (coming from a query string). We want to rely on the `text->domain` parser to do the right thing.
-pgFmtArrayLiteralForField values CoercibleField{cfTransform=(Just parserProc)} = SQL.sql "(SELECT " <> pgFmtCallUnary parserProc (SQL.sql "unnest(" <> unknownLiteral (pgBuildArrayLiteral values) <> "::text[])") <> ")"
-- When no transformation is requested, we don't need a subquery.
-pgFmtArrayLiteralForField values _ = unknownLiteral (pgBuildArrayLiteral values)
-
-
-pgFmtFilter :: QualifiedIdentifier -> CoercibleFilter -> SQL.Snippet
-pgFmtFilter _ (CoercibleFilterNullEmbed hasNot fld) = pgFmtIdent fld <> " IS " <> (if not hasNot then "NOT " else mempty) <> "DISTINCT FROM NULL"
-pgFmtFilter _ (CoercibleFilter _ (NoOpExpr _)) = mempty -- TODO unreachable because NoOpExpr is filtered on QueryParams
-pgFmtFilter table (CoercibleFilter fld (OpExpr hasNot oper)) = notOp <> " " <> pgFmtField table fld <> case oper of
-   Op op val  -> " " <> simpleOperator op <> " " <> pgFmtUnknownLiteralForField (unknownLiteral val) fld
-
-   OpQuant op quant val -> " " <> quantOperator op <> " " <> case op of
-     OpLike  -> fmtQuant quant $ unknownLiteral (T.map star val)
-     OpILike -> fmtQuant quant $ unknownLiteral (T.map star val)
-     _       -> fmtQuant quant $ pgFmtUnknownLiteralForField (unknownLiteral val) fld
+pgFmtFilter :: QualifiedIdentifier -> Filter -> SQL.Snippet
+pgFmtFilter table (Filter fld (OpExpr hasNot oper)) = notOp <> " " <> case oper of
+   Op op val  -> pgFmtFieldOp op <> " " <> case op of
+     "like"  -> unknownLiteral (T.map star val)
+     "ilike" -> unknownLiteral (T.map star val)
+     _       -> unknownLiteral val

   -- IS cannot be prepared. `PREPARE boolplan AS SELECT * FROM projects where id IS $1` will give a syntax error.
   -- The above can be fixed by using `PREPARE boolplan AS SELECT * FROM projects where id IS NOT DISTINCT FROM $1;`
   -- However that would not accept the TRUE/FALSE/NULL/UNKNOWN keywords. See: https://stackoverflow.com/questions/6133525/proper-way-to-set-preparedstatement-parameter-to-null-under-postgres.
   -- This is why `IS` operands are whitelisted at the Parsers.hs level
-   Is triVal -> " IS " <> case triVal of
+   Is triVal -> pgFmtField table fld <> " IS " <> case triVal of
     TriTrue    -> "TRUE"
     TriFalse   -> "FALSE"
     TriNull    -> "NULL"
     TriUnknown -> "UNKNOWN"

-   IsDistinctFrom val -> " IS DISTINCT FROM " <> unknownLiteral val
-
   -- We don't use "IN", we use "= ANY". IN has the following disadvantages:
   -- + No way to use an empty value on IN: "col IN ()" is invalid syntax. With ANY we can do "= ANY('{}')"
   -- + Can invalidate prepared statements: multiple parameters on an IN($1, $2, $3) will lead to using different prepared statements and not take advantage of caching.
-   In vals -> " " <> case vals of
+   In vals -> pgFmtField table fld <> " " <> case vals of
      [""] -> "= ANY('{}') "
-      _    -> "= ANY (" <> pgFmtArrayLiteralForField vals fld <> ") "
+      _    -> "= ANY (" <> unknownLiteral (pgBuildArrayLiteral vals) <> ") "

-   Fts op lang val -> " " <> ftsOperator op <> "(" <> ftsLang lang <> unknownLiteral val <> ") "
+   Fts op lang val ->
+     pgFmtFieldOp op <> "(" <> ftsLang lang <> unknownLiteral val <> ") "
 where
   ftsLang = maybe mempty (\l -> unknownLiteral l <> ", ")
+   pgFmtFieldOp op = pgFmtField table fld <> " " <> sqlOperator op
+   sqlOperator o = SQL.sql $ M.lookupDefault "=" o operators
   notOp = if hasNot then "NOT" else mempty
   star c = if c == '*' then '%' else c
-   fmtQuant q val = case q of
-    Just QuantAny -> "ANY(" <> val <> ")"
-    Just QuantAll -> "ALL(" <> val <> ")"
-    Nothing       -> val

 pgFmtJoinCondition :: JoinCondition -> SQL.Snippet
 pgFmtJoinCondition (JoinCondition (qi1, col1) (qi2, col2)) =
-  pgFmtColumn qi1 col1 <> " = " <> pgFmtColumn qi2 col2
+  SQL.sql $ pgFmtColumn qi1 col1 <> " = " <> pgFmtColumn qi2 col2

-pgFmtLogicTree :: QualifiedIdentifier -> CoercibleLogicTree -> SQL.Snippet
-pgFmtLogicTree qi (CoercibleExpr hasNot op forest) = SQL.sql notOp <> " (" <> intercalateSnippet (opSql op) (pgFmtLogicTree qi <$> forest) <> ")"
+pgFmtLogicTree :: QualifiedIdentifier -> LogicTree -> SQL.Snippet
+pgFmtLogicTree qi (Expr hasNot op forest) = SQL.sql notOp <> " (" <> intercalateSnippet (opSql op) (pgFmtLogicTree qi <$> forest) <> ")"
  where
    notOp =  if hasNot then "NOT" else mempty

    opSql And = " AND "
    opSql Or  = " OR "
-pgFmtLogicTree qi (CoercibleStmnt flt) = pgFmtFilter qi flt
+pgFmtLogicTree qi (Stmnt flt) = pgFmtFilter qi flt

 pgFmtJsonPath :: JsonPath -> SQL.Snippet
 pgFmtJsonPath = \case
@@ -398,7 +279,7 @@ pgFmtJsonPath = \case
    pgFmtJsonOperand (JKey k) = unknownLiteral k
    pgFmtJsonOperand (JIdx i) = unknownLiteral i <> "::int"

-pgFmtAs :: FieldName -> JsonPath -> Maybe Alias -> SQL.Snippet
+pgFmtAs :: FieldName -> JsonPath -> Maybe Alias -> SqlFragment
 pgFmtAs _ [] Nothing = mempty
 pgFmtAs fName jp Nothing = case jOp <$> lastMay jp of
  Just (JKey key) -> " AS " <> pgFmtIdent key
@@ -410,7 +291,7 @@ pgFmtAs fName jp Nothing = case jOp <$> lastMay jp of
  Nothing -> mempty
 pgFmtAs _ _ (Just alias) = " AS " <> pgFmtIdent alias

-countF :: SQL.Snippet -> Bool -> (SQL.Snippet, SQL.Snippet)
+countF :: SQL.Snippet -> Bool -> (SQL.Snippet, SqlFragment)
 countF countQuery shouldCount =
  if shouldCount
    then (
@@ -420,11 +301,11 @@ countF countQuery shouldCount =
        mempty
      , "null::bigint")

-returningF :: QualifiedIdentifier -> [FieldName] -> SQL.Snippet
+returningF :: QualifiedIdentifier -> [FieldName] -> SqlFragment
 returningF qi returnings =
  if null returnings
    then "RETURNING 1" -- For mutation cases where there's no ?select, we return 1 to know how many rows were modified
-    else "RETURNING " <> intercalateSnippet ", " (pgFmtColumn qi <$> returnings)
+    else "RETURNING " <> BS.intercalate ", " (pgFmtColumn qi <$> returnings)

 limitOffsetF :: NonnegRange -> SQL.Snippet
 limitOffsetF range =
@@ -433,28 +314,17 @@ limitOffsetF range =
    limit = maybe "ALL" (\l -> unknownEncoder (BS.pack $ show l)) $ rangeLimit range
    offset = unknownEncoder (BS.pack . show $ rangeOffset range)

-responseHeadersF :: SQL.Snippet
+responseHeadersF :: SqlFragment
 responseHeadersF = currentSettingF "response.headers"

-responseStatusF :: SQL.Snippet
+responseStatusF :: SqlFragment
 responseStatusF = currentSettingF "response.status"

-currentSettingF :: SQL.Snippet -> SQL.Snippet
+currentSettingF :: SqlFragment -> SqlFragment
 currentSettingF setting =
  -- nullif is used because of https://gist.github.com/steve-chavez/8d7033ea5655096903f3b52f8ed09a15
  "nullif(current_setting('" <> setting <> "', true), '')"

-mutRangeF :: QualifiedIdentifier -> [FieldName] -> (SQL.Snippet, SQL.Snippet)
-mutRangeF mainQi rangeId =
-  (
-    intercalateSnippet " AND " $ (\col -> pgFmtColumn mainQi col <> " = " <> pgFmtColumn (QualifiedIdentifier mempty "pgrst_affected_rows") col) <$> rangeId
-  , intercalateSnippet ", " (pgFmtColumn mainQi <$> rangeId)
-  )
-
-orderF :: QualifiedIdentifier -> [CoercibleOrderTerm] -> SQL.Snippet
-orderF _ []    = mempty
-orderF qi ordts = "ORDER BY " <> intercalateSnippet ", " (pgFmtOrderTerm qi <$> ordts)
-
 -- Hasql Snippet utilities
 unknownEncoder :: ByteString -> SQL.Snippet
 unknownEncoder = SQL.encoderAndParam (HE.nonNullable HE.unknown)
@@ -465,45 +335,3 @@ unknownLiteral = unknownEncoder . encodeUtf8
 intercalateSnippet :: ByteString -> [SQL.Snippet] -> SQL.Snippet
 intercalateSnippet _ [] = mempty
 intercalateSnippet frag snippets = foldr1 (\a b -> a <> SQL.sql frag <> b) snippets
-
-explainF :: MTPlanFormat -> [MTPlanOption] -> SQL.Snippet -> SQL.Snippet
-explainF fmt opts snip =
-  "EXPLAIN (" <>
-    SQL.sql (BS.intercalate ", " (fmtPlanFmt fmt : (fmtPlanOpt <$> opts))) <>
-  ") " <> snip
-  where
-    fmtPlanOpt :: MTPlanOption -> BS.ByteString
-    fmtPlanOpt PlanAnalyze  = "ANALYZE"
-    fmtPlanOpt PlanVerbose  = "VERBOSE"
-    fmtPlanOpt PlanSettings = "SETTINGS"
-    fmtPlanOpt PlanBuffers  = "BUFFERS"
-    fmtPlanOpt PlanWAL      = "WAL"
-
-    fmtPlanFmt PlanText = "FORMAT TEXT"
-    fmtPlanFmt PlanJSON = "FORMAT JSON"
-
-- | Do a pg set_config(setting, value, true) call. This is equivalent to a SET LOCAL.
-setConfigLocal :: ByteString -> (ByteString, ByteString) -> SQL.Snippet
-setConfigLocal prefix (k, v) =
-  "set_config(" <> unknownEncoder (prefix <> k) <> ", " <> unknownEncoder v <> ", true)"
-
-- | Starting from PostgreSQL v14, some characters are not allowed for config names (mostly affecting headers with "-").
-- | A JSON format string is used to avoid this problem. See https://github.com/PostgREST/postgrest/issues/1857
-setConfigLocalJson :: ByteString -> [(ByteString, ByteString)] -> [SQL.Snippet]
-setConfigLocalJson prefix keyVals = [setConfigLocal mempty (prefix, gucJsonVal keyVals)]
-  where
-    gucJsonVal :: [(ByteString, ByteString)] -> ByteString
-    gucJsonVal = LBS.toStrict . JSON.encode . HM.fromList . arrayByteStringToText
-    arrayByteStringToText :: [(ByteString, ByteString)] -> [(Text,Text)]
-    arrayByteStringToText keyVal = (T.decodeUtf8 *** T.decodeUtf8) <$> keyVal
-
-aggF :: Maybe Routine -> ResultAggregate -> SQL.Snippet
-aggF rout = \case
-  BuiltinAggJson             -> asJsonF rout False
-  BuiltinAggArrayJsonStrip   -> asJsonF rout True
-  BuiltinAggSingleJson strip -> asJsonSingleF rout strip
-  BuiltinAggGeoJson          -> asGeoJsonF
-  BuiltinAggCsv              -> asCsvF
-  BuiltinAggXml    bField    -> asXmlF    bField
-  BuiltinAggBinary bField    -> asBinaryF bField
-  NoAgg                      -> "''::text"
@@ -6,164 +6,192 @@ This module constructs single SQL statements that can be parametrized and prepar

 - It consumes the SqlQuery types generated by the QueryBuilder module.
 - It generates the body format and some headers of the final HTTP response.
+
+TODO: Currently, createReadStatement is not using prepared statements. See https://github.com/PostgREST/postgrest/issues/718.
 -}
 module PostgREST.Query.Statements
-  ( prepareWrite
-  , prepareRead
-  , prepareCall
-  , preparePlanRows
-  , ResultSet (..)
+  ( createWriteStatement
+  , createReadStatement
+  , callProcStatement
+  , createExplainStatement
  ) where

+import qualified Data.Aeson                        as JSON
 import qualified Data.Aeson.Lens                   as L
 import qualified Data.ByteString.Char8             as BS
+import qualified Data.ByteString.Lazy              as LBS
 import qualified Hasql.Decoders                    as HD
 import qualified Hasql.DynamicStatements.Snippet   as SQL
 import qualified Hasql.DynamicStatements.Statement as SQL
 import qualified Hasql.Statement                   as SQL

-import Control.Lens ((^?))
+import Control.Lens              ((^?))
+import Data.Maybe                (fromJust)
+import Data.Text.Read            (decimal)
+import Network.HTTP.Types.Status (Status)

-import PostgREST.ApiRequest.Preferences
-import PostgREST.MediaType              (MTPlanFormat (..),
-                                         MediaType (..))
+import PostgREST.Error     (Error (..))
+import PostgREST.GucHeader (GucHeader)
+
+import PostgREST.DbStructure.Identifiers (FieldName)
 import PostgREST.Query.SqlFragment
-import PostgREST.SchemaCache.Routine    (ResultAggregate (..),
-                                         Routine)
+import PostgREST.Request.Preferences

 import Protolude

-- | Standard result set format used for all queries
-data ResultSet
-  = RSStandard
-  { rsTableTotal :: Maybe Int64
-  -- ^ count of all the table rows
-  , rsQueryTotal :: Int64
-  -- ^ count of the query rows
-  , rsLocation   :: [(BS.ByteString, BS.ByteString)]
-  -- ^ The Location header(only used for inserts) is represented as a list of strings containing
-  -- variable bindings like @"k1=eq.42"@, or the empty list if there is no location header.
-  , rsBody       :: BS.ByteString
-  -- ^ the aggregated body of the query
-  , rsGucHeaders :: Maybe BS.ByteString
-  -- ^ the HTTP headers to be added to the response
-  , rsGucStatus  :: Maybe Text
-  -- ^ the HTTP status to be added to the response
-  }
-  | RSPlan BS.ByteString -- ^ the plan of the query
+{-| The generic query result format used by API responses. The location header
+    is represented as a list of strings containing variable bindings like
+    @"k1=eq.42"@, or the empty list if there is no location header.
+-}
+type ResultsWithCount = (Maybe Int64, Int64, [BS.ByteString], BS.ByteString, Either Error [GucHeader], Either Error (Maybe Status))

-
-prepareWrite :: SQL.Snippet -> SQL.Snippet -> Bool -> MediaType -> ResultAggregate ->
-                Maybe PreferRepresentation -> [Text] -> Bool -> SQL.Statement () ResultSet
-prepareWrite selectQuery mutateQuery isInsert mt rAgg rep pKeys =
-  SQL.dynamicallyParameterized (mtSnippet mt snippet) decodeIt
+createWriteStatement :: SQL.Snippet -> SQL.Snippet -> Bool -> Bool -> Bool ->
+                        PreferRepresentation -> [Text] -> Bool ->
+                        SQL.Statement () ResultsWithCount
+createWriteStatement selectQuery mutateQuery wantSingle isInsert asCsv rep pKeys =
+  SQL.dynamicallyParameterized snippet decodeStandard
 where
  snippet =
-    "WITH " <> sourceCTE <> " AS (" <> mutateQuery <> ") " <>
+    "WITH " <> SQL.sql sourceCTEName <> " AS (" <> mutateQuery <> ") " <>
+    SQL.sql (
    "SELECT " <>
      "'' AS total_result_set, " <>
      "pg_catalog.count(_postgrest_t) AS page_total, " <>
      locF <> " AS header, " <>
-      aggF Nothing rAgg <> " AS body, " <>
+      bodyF <> " AS body, " <>
      responseHeadersF <> " AS response_headers, " <>
-      responseStatusF  <> " AS response_status " <>
+      responseStatusF  <> " AS response_status "
+    ) <>
    "FROM (" <> selectF <> ") _postgrest_t"

  locF =
-    if isInsert && rep == Just HeadersOnly
-      then
-        "CASE WHEN pg_catalog.count(_postgrest_t) = 1 " <>
-          "THEN coalesce(" <> locationF pKeys <> ", " <> noLocationF <> ") " <>
-          "ELSE " <> noLocationF <> " " <>
-        "END"
+    if isInsert && rep `elem` [Full, HeadersOnly]
+      then BS.unwords [
+        "CASE WHEN pg_catalog.count(_postgrest_t) = 1",
+          "THEN coalesce(" <> locationF pKeys <> ", " <> noLocationF <> ")",
+          "ELSE " <> noLocationF,
+        "END"]
      else noLocationF

+  bodyF
+    | rep `elem` [None, HeadersOnly] = "''"
+    | asCsv = asCsvF
+    | wantSingle = asJsonSingleF False
+    | otherwise = asJsonF False
+
  selectF
    -- prevent using any of the column names in ?select= when no response is returned from the CTE
-    | rAgg == NoAgg = "SELECT * FROM " <> sourceCTE
-    | otherwise     = selectQuery
+    | rep `elem` [None, HeadersOnly] = SQL.sql ("SELECT * FROM " <> sourceCTEName)
+    | otherwise                      = selectQuery

-  decodeIt :: HD.Result ResultSet
-  decodeIt = case mt of
-    MTPlan{} -> planRow
-    _        -> fromMaybe (RSStandard Nothing 0 mempty mempty Nothing Nothing) <$> HD.rowMaybe (standardRow False)
+  decodeStandard :: HD.Result ResultsWithCount
+  decodeStandard =
+   fromMaybe (Nothing, 0, [], mempty, Right [], Right Nothing) <$> HD.rowMaybe standardRow

-prepareRead :: SQL.Snippet -> SQL.Snippet -> Bool -> MediaType -> ResultAggregate -> Bool -> SQL.Statement () ResultSet
-prepareRead selectQuery countQuery countTotal mt rAgg =
-  SQL.dynamicallyParameterized (mtSnippet mt snippet) decodeIt
+createReadStatement :: SQL.Snippet -> SQL.Snippet -> Bool -> Bool -> Bool -> Maybe FieldName -> Bool ->
+                       SQL.Statement () ResultsWithCount
+createReadStatement selectQuery countQuery isSingle countTotal asCsv binaryField =
+  SQL.dynamicallyParameterized snippet decodeStandard
 where
  snippet =
-    "WITH " <> sourceCTE <> " AS ( " <> selectQuery <> " ) " <>
+    "WITH " <>
+    SQL.sql sourceCTEName <> " AS ( " <> selectQuery <> " ) " <>
    countCTEF <> " " <>
-    "SELECT " <>
+    SQL.sql ("SELECT " <>
      countResultF <> " AS total_result_set, " <>
      "pg_catalog.count(_postgrest_t) AS page_total, " <>
-      aggF Nothing rAgg <> " AS body, " <>
+      noLocationF <> " AS header, " <>
+      bodyF <> " AS body, " <>
      responseHeadersF <> " AS response_headers, " <>
      responseStatusF <> " AS response_status " <>
-    "FROM ( SELECT * FROM " <> sourceCTE <> " ) _postgrest_t"
+    "FROM ( SELECT * FROM " <> sourceCTEName <> " ) _postgrest_t")

  (countCTEF, countResultF) = countF countQuery countTotal

-  decodeIt :: HD.Result ResultSet
-  decodeIt = case mt of
-    MTPlan{} -> planRow
-    _        -> HD.singleRow $ standardRow True
+  bodyF
+    | asCsv = asCsvF
+    | isSingle = asJsonSingleF False
+    | isJust binaryField = asBinaryF $ fromJust binaryField
+    | otherwise = asJsonF False

-prepareCall :: Routine -> SQL.Snippet -> SQL.Snippet -> SQL.Snippet -> Bool ->
-               MediaType -> ResultAggregate -> Bool ->
-               SQL.Statement () ResultSet
-prepareCall rout callProcQuery selectQuery countQuery countTotal mt rAgg =
-  SQL.dynamicallyParameterized (mtSnippet mt snippet) decodeIt
+  decodeStandard :: HD.Result ResultsWithCount
+  decodeStandard =
+    HD.singleRow standardRow
+
+{-| Read and Write api requests use a similar response format which includes
+    various record counts and possible location header. This is the decoder
+    for that common type of query.
+-}
+standardRow :: HD.Row ResultsWithCount
+standardRow = (,,,,,) <$> nullableColumn HD.int8 <*> column HD.int8
+                      <*> arrayColumn HD.bytea <*> column HD.bytea
+                      <*> (fromMaybe (Right []) <$> nullableColumn decodeGucHeaders)
+                      <*> (fromMaybe (Right Nothing) <$> nullableColumn decodeGucStatus)
+
+type ProcResults = (Maybe Int64, Int64, ByteString, Either Error [GucHeader], Either Error (Maybe Status))
+
+callProcStatement :: Bool -> Bool -> SQL.Snippet -> SQL.Snippet -> SQL.Snippet -> Bool ->
+                     Bool -> Bool -> Bool -> Maybe FieldName -> Bool ->
+                     SQL.Statement () ProcResults
+callProcStatement returnsScalar returnsSingle callProcQuery selectQuery countQuery countTotal asSingle asCsv multObjects binaryField =
+  SQL.dynamicallyParameterized snippet decodeProc
  where
    snippet =
-      "WITH " <> sourceCTE <> " AS (" <> callProcQuery <> ") " <>
+      "WITH " <> SQL.sql sourceCTEName <> " AS (" <> callProcQuery <> ") " <>
      countCTEF <>
+      SQL.sql (
      "SELECT " <>
        countResultF <> " AS total_result_set, " <>
        "pg_catalog.count(_postgrest_t) AS page_total, " <>
-        aggF (Just rout) rAgg <> " AS body, " <>
+        bodyF <> " AS body, " <>
        responseHeadersF <> " AS response_headers, " <>
-        responseStatusF <> " AS response_status " <>
+        responseStatusF <> " AS response_status ") <>
      "FROM (" <> selectQuery <> ") _postgrest_t"

    (countCTEF, countResultF) = countF countQuery countTotal

-    decodeIt :: HD.Result ResultSet
-    decodeIt = case mt of
-      MTPlan{} -> planRow
-      _        -> fromMaybe (RSStandard (Just 0) 0 mempty mempty Nothing Nothing) <$> HD.rowMaybe (standardRow True)
+    bodyF
+     | asSingle           = asJsonSingleF returnsScalar
+     | asCsv              = asCsvF
+     | isJust binaryField = asBinaryF $ fromJust binaryField
+     | returnsSingle
+       && not multObjects = asJsonSingleF returnsScalar
+     | otherwise          = asJsonF returnsScalar

-preparePlanRows :: SQL.Snippet -> Bool -> SQL.Statement () (Maybe Int64)
-preparePlanRows countQuery =
-  SQL.dynamicallyParameterized snippet decodeIt
+    decodeProc :: HD.Result ProcResults
+    decodeProc =
+      fromMaybe (Just 0, 0, mempty, defGucHeaders, defGucStatus) <$> HD.rowMaybe procRow
+      where
+        defGucHeaders = Right []
+        defGucStatus  = Right Nothing
+        procRow = (,,,,) <$> nullableColumn HD.int8 <*> column HD.int8
+                         <*> column HD.bytea
+                         <*> (fromMaybe defGucHeaders <$> nullableColumn decodeGucHeaders)
+                         <*> (fromMaybe defGucStatus <$> nullableColumn decodeGucStatus)
+
+createExplainStatement :: SQL.Snippet -> Bool -> SQL.Statement () (Maybe Int64)
+createExplainStatement countQuery =
+  SQL.dynamicallyParameterized snippet decodeExplain
  where
-    snippet = explainF PlanJSON mempty countQuery
-    decodeIt :: HD.Result (Maybe Int64)
-    decodeIt =
+    snippet = "EXPLAIN (FORMAT JSON) " <> countQuery
+    -- |
+    -- An `EXPLAIN (FORMAT JSON) select * from items;` output looks like this:
+    -- [{
+    --   "Plan": {
+    --     "Node Type": "Seq Scan", "Parallel Aware": false, "Relation Name": "items",
+    --     "Alias": "items", "Startup Cost": 0.00, "Total Cost": 32.60,
+    --     "Plan Rows": 2260,"Plan Width": 8} }]
+    -- We only obtain the Plan Rows here.
+    decodeExplain :: HD.Result (Maybe Int64)
+    decodeExplain =
      let row = HD.singleRow $ column HD.bytea in
      (^? L.nth 0 . L.key "Plan" .  L.key "Plan Rows" . L._Integral) <$> row

-standardRow :: Bool -> HD.Row ResultSet
-standardRow noLocation =
-  RSStandard <$> nullableColumn HD.int8 <*> column HD.int8
-             <*> (if noLocation then pure mempty else fmap splitKeyValue <$> arrayColumn HD.bytea) <*> column HD.bytea
-             <*> nullableColumn HD.bytea
-             <*> nullableColumn HD.text
-  where
-    splitKeyValue :: ByteString -> (ByteString, ByteString)
-    splitKeyValue kv =
-      let (k, v) = BS.break (== '=') kv in
-      (k, BS.tail v)
+decodeGucHeaders :: HD.Value (Either Error [GucHeader])
+decodeGucHeaders = first (const GucHeadersError) . JSON.eitherDecode . LBS.fromStrict <$> HD.bytea

-mtSnippet :: MediaType -> SQL.Snippet -> SQL.Snippet
-mtSnippet mediaType snippet = case mediaType of
-  MTPlan _ fmt opts -> explainF fmt opts snippet
-  _                 -> snippet
-
-- | We use rowList because when doing EXPLAIN (FORMAT TEXT), the result comes as many rows. FORMAT JSON comes as one.
-planRow :: HD.Result ResultSet
-planRow = RSPlan . BS.unlines <$> HD.rowList (column HD.bytea)
+decodeGucStatus :: HD.Value (Either Error (Maybe Status))
+decodeGucStatus = first (const GucStatusError) . fmap (Just . toEnum . fst) . decimal <$> HD.text

 column :: HD.Value a -> HD.Row a
 column = HD.column . HD.nonNullable
@@ -10,9 +10,6 @@ module PostgREST.RangeQuery (
 , restrictRange
 , rangeGeq
 , allRange
-, limitZeroRange
-, hasLimitZero
-, convertToLimitZeroRange
 , NonnegRange
 , rangeStatusHeader
 , contentRangeH
@@ -37,14 +34,13 @@ rangeParse :: BS.ByteString -> NonnegRange
 rangeParse range = do
  let rangeRegex = "^([0-9]+)-([0-9]*)$" :: BS.ByteString

-  case range =~ rangeRegex :: [[BS.ByteString]] of
-    [[_, l, u]] ->
-      let lower  = maybe emptyRange rangeGeq (readInteger l)
-          upper  = maybe allRange rangeLeq (readInteger u) in
+  case listToMaybe (range =~ rangeRegex :: [[BS.ByteString]]) of
+    Just parsedRange ->
+      let [_, mLower, mUpper] = readMaybe . BS.unpack <$> parsedRange
+          lower         = maybe emptyRange rangeGeq mLower
+          upper         = maybe allRange rangeLeq mUpper in
      rangeIntersection lower upper
-    _ -> allRange
-  where
-    readInteger = readMaybe . BS.unpack
+    Nothing -> allRange

 rangeRequested :: RequestHeaders -> NonnegRange
 rangeRequested headers = maybe allRange rangeParse $ lookup hRange headers
@@ -78,21 +74,6 @@ rangeLeq :: Integer -> NonnegRange
 rangeLeq n =
  Range BoundaryBelowAll (BoundaryAbove n)

-- Special case to allow limit 0 queries
-- https://github.com/PostgREST/postgrest/issues/1121
-- 0 <= x <= -1
-limitZeroRange :: Range Integer
-limitZeroRange = Range (BoundaryBelow 0) (BoundaryAbove (-1))
-
-hasLimitZero :: Range Integer -> Bool
-hasLimitZero r = rangeUpper r == rangeUpper limitZeroRange
-
-- Used to convert a range into a special limitZeroRange if it has a
-- limit=0 in order to bypass validations for empty ranges.
-convertToLimitZeroRange :: Range Integer -> Range Integer -> Range Integer
-convertToLimitZeroRange range fallbackRange =
-  if hasLimitZero range then limitZeroRange else fallbackRange
-
 rangeStatusHeader :: NonnegRange -> Int64 -> Maybe Int64 -> (Status, Header)
 rangeStatusHeader topLevelRange queryTotal tableTotal =
  let lower = rangeOffset topLevelRange
@@ -0,0 +1,518 @@
+{-|
+Module      : PostgREST.Request.ApiRequest
+Description : PostgREST functions to translate HTTP request to a domain type called ApiRequest.
+-}
+{-# LANGUAGE LambdaCase      #-}
+{-# LANGUAGE NamedFieldPuns  #-}
+{-# LANGUAGE RecordWildCards #-}
+
+module PostgREST.Request.ApiRequest
+  ( ApiRequest(..)
+  , InvokeMethod(..)
+  , ContentType(..)
+  , Action(..)
+  , Target(..)
+  , Payload(..)
+  , userApiRequest
+  ) where
+
+import qualified Data.Aeson            as JSON
+import qualified Data.ByteString.Char8 as BS
+import qualified Data.ByteString.Lazy  as LBS
+import qualified Data.CaseInsensitive  as CI
+import qualified Data.Csv              as CSV
+import qualified Data.HashMap.Strict   as M
+import qualified Data.List             as L
+import qualified Data.List.NonEmpty    as NonEmptyList
+import qualified Data.Set              as S
+import qualified Data.Text             as T
+import qualified Data.Text.Encoding    as T
+import qualified Data.Vector           as V
+
+import Control.Arrow             ((***))
+import Data.Aeson.Types          (emptyArray, emptyObject)
+import Data.List                 (last, lookup, partition, union)
+import Data.Maybe                (fromJust)
+import Data.Ranged.Boundaries    (Boundary (..))
+import Data.Ranged.Ranges        (Range (..), emptyRange,
+                                  rangeIntersection)
+import Network.HTTP.Base         (urlEncodeVars)
+import Network.HTTP.Types.Header (hAuthorization, hCookie)
+import Network.HTTP.Types.URI    (parseQueryReplacePlus,
+                                  parseSimpleQuery)
+import Network.Wai               (Request (..))
+import Network.Wai.Parse         (parseHttpAccept)
+import Web.Cookie                (parseCookies)
+
+import PostgREST.Config                  (AppConfig (..),
+                                          OpenAPIMode (..))
+import PostgREST.ContentType             (ContentType (..))
+import PostgREST.DbStructure             (DbStructure (..))
+import PostgREST.DbStructure.Identifiers (FieldName,
+                                          QualifiedIdentifier (..),
+                                          Schema)
+import PostgREST.DbStructure.Proc        (ProcDescription (..),
+                                          ProcParam (..), ProcsMap)
+import PostgREST.Error                   (ApiRequestError (..))
+import PostgREST.Query.SqlFragment       (ftsOperators, operators)
+import PostgREST.RangeQuery              (NonnegRange, allRange,
+                                          rangeGeq, rangeLimit,
+                                          rangeOffset, rangeRequested,
+                                          restrictRange)
+import PostgREST.Request.Parsers         (pRequestColumns)
+import PostgREST.Request.Preferences     (PreferCount (..),
+                                          PreferParameters (..),
+                                          PreferRepresentation (..),
+                                          PreferResolution (..),
+                                          PreferTransaction (..))
+
+import qualified PostgREST.ContentType         as ContentType
+import qualified PostgREST.Request.Preferences as Preferences
+
+import Protolude
+
+
+type RequestBody = LBS.ByteString
+
+data Payload
+  = ProcessedJSON -- ^ Cached attributes of a JSON payload
+      { payRaw  :: LBS.ByteString
+      -- ^ This is the raw ByteString that comes from the request body.  We
+      -- cache this instead of an Aeson Value because it was detected that for
+      -- large payloads the encoding had high memory usage, see
+      -- https://github.com/PostgREST/postgrest/pull/1005 for more details
+      , payKeys :: S.Set Text
+      -- ^ Keys of the object or if it's an array these keys are guaranteed to
+      -- be the same across all its objects
+      }
+  | RawJSON { payRaw  :: LBS.ByteString }
+  | RawPay  { payRaw  :: LBS.ByteString }
+
+data InvokeMethod = InvHead | InvGet | InvPost deriving Eq
+-- | Types of things a user wants to do to tables/views/procs
+data Action = ActionCreate       | ActionRead{isHead :: Bool}
+            | ActionUpdate       | ActionDelete
+            | ActionSingleUpsert | ActionInvoke InvokeMethod
+            | ActionInfo         | ActionInspect{isHead :: Bool}
+            deriving Eq
+-- | The path info that will be mapped to a target (used to handle validations and errors before defining the Target)
+data Path
+  = PathInfo
+      { pSchema        :: Schema,
+        pName          :: Text,
+        pHasRpc        :: Bool,
+        pIsDefaultSpec :: Bool,
+        pIsRootSpec    :: Bool
+      }
+  | PathUnknown
+-- | The target db object of a user action
+data Target = TargetIdent QualifiedIdentifier
+            | TargetProc{tProc :: ProcDescription, tpIsRootSpec :: Bool}
+            | TargetDefaultSpec{tdsSchema :: Schema} -- The default spec offered at root "/"
+            | TargetUnknown
+
+-- | RPC query param value `/rpc/func?v=<value>`, used for VARIADIC functions on form-urlencoded POST and GETs
+-- | It can be fixed `?v=1` or repeated `?v=1&v=2&v=3.
+data RpcParamValue = Fixed Text | Variadic [Text]
+instance JSON.ToJSON RpcParamValue where
+  toJSON (Fixed    v) = JSON.toJSON v
+  toJSON (Variadic v) = JSON.toJSON v
+
+toRpcParamValue :: ProcDescription -> (Text, Text) -> (Text, RpcParamValue)
+toRpcParamValue proc (k, v) | prmIsVariadic k = (k, Variadic [v])
+                            | otherwise       = (k, Fixed v)
+  where
+    prmIsVariadic prm = isJust $ find (\ProcParam{ppName, ppVar} -> ppName == prm && ppVar) $ pdParams proc
+
+-- | Convert rpc params `/rpc/func?a=val1&b=val2` to json `{"a": "val1", "b": "val2"}
+jsonRpcParams :: ProcDescription -> [(Text, Text)] -> Payload
+jsonRpcParams proc prms =
+  if not $ pdHasVariadic proc then -- if proc has no variadic param, save steps and directly convert to json
+    ProcessedJSON (JSON.encode $ M.fromList $ second JSON.toJSON <$> prms) (S.fromList $ fst <$> prms)
+  else
+    let paramsMap = M.fromListWith mergeParams $ toRpcParamValue proc <$> prms in
+    ProcessedJSON (JSON.encode paramsMap) (S.fromList $ M.keys paramsMap)
+  where
+    mergeParams :: RpcParamValue -> RpcParamValue -> RpcParamValue
+    mergeParams (Variadic a) (Variadic b) = Variadic $ b ++ a
+    mergeParams v _                       = v -- repeated params for non-variadic parameters are not merged
+
+targetToJsonRpcParams :: Maybe Target -> [(Text, Text)] -> Maybe Payload
+targetToJsonRpcParams target params =
+  case target of
+    Just TargetProc{tProc} -> Just $ jsonRpcParams tProc params
+    _                      -> Nothing
+
+{-|
+  Describes what the user wants to do. This data type is a
+  translation of the raw elements of an HTTP request into domain
+  specific language.  There is no guarantee that the intent is
+  sensible, it is up to a later stage of processing to determine
+  if it is an action we are able to perform.
+-}
+data ApiRequest = ApiRequest {
+    iAction               :: Action                           -- ^ Similar but not identical to HTTP verb, e.g. Create/Invoke both POST
+  , iRange                :: M.HashMap Text NonnegRange -- ^ Requested range of rows within response
+  , iTopLevelRange        :: NonnegRange                      -- ^ Requested range of rows from the top level
+  , iTarget               :: Target                           -- ^ The target, be it calling a proc or accessing a table
+  , iPayload              :: Maybe Payload                    -- ^ Data sent by client and used for mutation actions
+  , iPreferRepresentation :: PreferRepresentation             -- ^ If client wants created items echoed back
+  , iPreferParameters     :: Maybe PreferParameters           -- ^ How to pass parameters to a stored procedure
+  , iPreferCount          :: Maybe PreferCount                -- ^ Whether the client wants a result count
+  , iPreferResolution     :: Maybe PreferResolution           -- ^ Whether the client wants to UPSERT or ignore records on PK conflict
+  , iPreferTransaction    :: Maybe PreferTransaction          -- ^ Whether the clients wants to commit or rollback the transaction
+  , iFilters              :: [(Text, Text)]                   -- ^ Filters on the result ("id", "eq.10")
+  , iLogic                :: [(Text, Text)]                   -- ^ &and and &or parameters used for complex boolean logic
+  , iSelect               :: Maybe Text                       -- ^ &select parameter used to shape the response
+  , iOnConflict           :: Maybe Text                       -- ^ &on_conflict parameter used to upsert on specific unique keys
+  , iColumns              :: S.Set FieldName                  -- ^ parsed colums from &columns parameter and payload
+  , iOrder                :: [(Text, Text)]                   -- ^ &order parameters for each level
+  , iCanonicalQS          :: ByteString                       -- ^ Alphabetized (canonical) request query string for response URLs
+  , iJWT                  :: Text                             -- ^ JSON Web Token
+  , iHeaders              :: [(ByteString, ByteString)]       -- ^ HTTP request headers
+  , iCookies              :: [(ByteString, ByteString)]       -- ^ Request Cookies
+  , iPath                 :: ByteString                       -- ^ Raw request path
+  , iMethod               :: ByteString                       -- ^ Raw request method
+  , iProfile              :: Maybe Schema                     -- ^ The request profile for enabling use of multiple schemas. Follows the spec in hhttps://www.w3.org/TR/dx-prof-conneg/ttps://www.w3.org/TR/dx-prof-conneg/.
+  , iSchema               :: Schema                           -- ^ The request schema. Can vary depending on iProfile.
+  , iAcceptContentType    :: ContentType
+  }
+
+-- | Examines HTTP request and translates it into user intent.
+userApiRequest :: AppConfig -> DbStructure -> Request -> RequestBody -> Either ApiRequestError ApiRequest
+userApiRequest conf@AppConfig{..} dbStructure req reqBody
+  | isJust profile && fromJust profile `notElem` configDbSchemas = Left $ UnacceptableSchema $ toList configDbSchemas
+  | isTargetingProc && method `notElem` ["HEAD", "GET", "POST"] = Left ActionInappropriate
+  | topLevelRange == emptyRange = Left InvalidRange
+  | shouldParsePayload && isLeft payload = either (Left . InvalidBody) witness payload
+  | isLeft parsedColumns = either Left witness parsedColumns
+  | otherwise = do
+     acceptContentType <- findAcceptContentType conf action path accepts
+     checkedTarget <- target
+     return ApiRequest {
+      iAction = action
+      , iTarget = checkedTarget
+      , iRange = ranges
+      , iTopLevelRange = topLevelRange
+      , iPayload = relevantPayload
+      , iPreferRepresentation = fromMaybe None preferRepresentation
+      , iPreferParameters = preferParameters
+      , iPreferCount = preferCount
+      , iPreferResolution = preferResolution
+      , iPreferTransaction = preferTransaction
+      , iFilters = filters
+      , iLogic = [(toS k, toS $ fromJust v) | (k,v) <- qParams, isJust v, endingIn ["and", "or"] k ]
+      , iSelect = toS <$> join (lookup "select" qParams)
+      , iOnConflict = toS <$> join (lookup "on_conflict" qParams)
+      , iColumns = payloadColumns
+      , iOrder = [(toS k, toS $ fromJust v) | (k,v) <- qParams, isJust v, endingIn ["order"] k ]
+      , iCanonicalQS = BS.pack $ urlEncodeVars
+        . L.sortOn fst
+        . map (join (***) BS.unpack . second (fromMaybe mempty))
+        $ qString
+      , iJWT = tokenStr
+      , iHeaders = [ (CI.foldedCase k, v) | (k,v) <- hdrs, k /= hCookie]
+      , iCookies = maybe [] parseCookies $ lookupHeader "Cookie"
+      , iPath = rawPathInfo req
+      , iMethod = method
+      , iProfile = profile
+      , iSchema = schema
+      , iAcceptContentType = acceptContentType
+      }
+ where
+  accepts = maybe [CTAny] (map ContentType.decodeContentType . parseHttpAccept) $ lookupHeader "accept"
+  -- queryString with '+' converted to ' '(space)
+  qString = parseQueryReplacePlus True $ rawQueryString req
+  -- rpcQParams = Rpc query params e.g. /rpc/name?param1=val1, similar to filter but with no operator(eq, lt..)
+  (filters, rpcQParams) =
+    case action of
+      ActionInvoke InvGet  -> partitionFlts
+      ActionInvoke InvHead -> partitionFlts
+      _                    -> (flts, [])
+  partitionFlts = partition (liftM2 (||) (isEmbedPath . fst) (hasOperator . snd)) flts
+  flts =
+    [ (toS k, toS $ fromJust v) |
+      (k,v) <- qParams, isJust v,
+      k `notElem` ["select", "columns"],
+      not (endingIn ["order", "limit", "offset", "and", "or"] k) ]
+  hasOperator val = any (`T.isPrefixOf` val) $
+                      ((<> ".") <$> "not":M.keys operators) ++
+                      ((<> "(") <$> M.keys ftsOperators)
+  isEmbedPath = T.isInfixOf "."
+  isTargetingProc = case path of
+    PathInfo{pHasRpc, pIsRootSpec} -> pHasRpc || pIsRootSpec
+    _                              -> False
+  isTargetingDefaultSpec = case path of
+    PathInfo{pIsDefaultSpec=True} -> True
+    _                             -> False
+  contentType = maybe CTApplicationJSON ContentType.decodeContentType $ lookupHeader "content-type"
+  columns
+    | action `elem` [ActionCreate, ActionUpdate, ActionInvoke InvPost] = toS <$> join (lookup "columns" qParams)
+    | otherwise = Nothing
+  parsedColumns = pRequestColumns columns
+  payloadColumns =
+    case (contentType, action) of
+      (_, ActionInvoke InvGet)  -> S.fromList $ fst <$> rpcQParams
+      (_, ActionInvoke InvHead) -> S.fromList $ fst <$> rpcQParams
+      (CTUrlEncoded, _)         -> S.fromList $ map (T.decodeUtf8 . fst) $ parseSimpleQuery $ LBS.toStrict reqBody
+      _ -> case (relevantPayload, fromRight Nothing parsedColumns) of
+        (Just ProcessedJSON{payKeys}, _) -> payKeys
+        (Just RawJSON{}, Just cls)       -> cls
+        _                                -> S.empty
+  payload :: Either ByteString Payload
+  payload = case contentType of
+    CTApplicationJSON ->
+      if isJust columns
+        then Right $ RawJSON reqBody
+        else note "All object keys must match" . payloadAttributes reqBody
+               =<< if LBS.null reqBody && isTargetingProc
+                     then Right emptyObject
+                     else first BS.pack $ JSON.eitherDecode reqBody
+    CTTextCSV -> do
+      json <- csvToJson <$> first BS.pack (CSV.decodeByName reqBody)
+      note "All lines must have same number of fields" $ payloadAttributes (JSON.encode json) json
+    CTUrlEncoded ->
+      let paramsMap = M.fromList $ (T.decodeUtf8 *** JSON.String . T.decodeUtf8) <$> parseSimpleQuery (LBS.toStrict reqBody) in
+      Right $ ProcessedJSON (JSON.encode paramsMap) $ S.fromList (M.keys paramsMap)
+    ct ->
+      if isTargetingProc && ct `elem` [CTTextPlain, CTOctetStream]
+        then Right $ RawPay reqBody
+        else Left $ "Content-Type not acceptable: " <> ContentType.toMime ct
+  topLevelRange = fromMaybe allRange $ M.lookup "limit" ranges -- if no limit is specified, get all the request rows
+  action =
+    case method of
+      -- The HEAD method is identical to GET except that the server MUST NOT return a message-body in the response
+      -- From https://www.w3.org/Protocols/rfc2616/rfc2616-sec9.html#sec9.4
+      "HEAD"     | isTargetingDefaultSpec -> ActionInspect{isHead=True}
+                 | isTargetingProc        -> ActionInvoke InvHead
+                 | otherwise              -> ActionRead{isHead=True}
+      "GET"      | isTargetingDefaultSpec -> ActionInspect{isHead=False}
+                 | isTargetingProc        -> ActionInvoke InvGet
+                 | otherwise              -> ActionRead{isHead=False}
+      "POST"    -> if isTargetingProc
+                    then ActionInvoke InvPost
+                    else ActionCreate
+      "PATCH"   -> ActionUpdate
+      "PUT"     -> ActionSingleUpsert
+      "DELETE"  -> ActionDelete
+      "OPTIONS" -> ActionInfo
+      _         -> ActionInspect{isHead=False}
+
+  defaultSchema = NonEmptyList.head configDbSchemas
+  profile
+    | length configDbSchemas <= 1 -- only enable content negotiation by profile when there are multiple schemas specified in the config
+      = Nothing
+    | otherwise = case action of
+        -- POST/PATCH/PUT/DELETE don't use the same header as per the spec
+        ActionCreate         -> contentProfile
+        ActionUpdate         -> contentProfile
+        ActionSingleUpsert   -> contentProfile
+        ActionDelete         -> contentProfile
+        ActionInvoke InvPost -> contentProfile
+        _                    -> acceptProfile
+    where
+      contentProfile = Just $ maybe defaultSchema T.decodeUtf8 $ lookupHeader "Content-Profile"
+      acceptProfile = Just $ maybe defaultSchema T.decodeUtf8 $ lookupHeader "Accept-Profile"
+  schema = fromMaybe defaultSchema profile
+  target =
+    let
+      callFindProc procSch procNam = findProc
+        (QualifiedIdentifier procSch procNam) payloadColumns (preferParameters == Just SingleObject) (dbProcs dbStructure)
+        contentType (action == ActionInvoke InvPost)
+    in
+    case path of
+      PathInfo{pSchema, pName, pHasRpc, pIsRootSpec, pIsDefaultSpec}
+        | pHasRpc || pIsRootSpec -> (`TargetProc` pIsRootSpec) <$> callFindProc pSchema pName
+        | pIsDefaultSpec         -> Right $ TargetDefaultSpec pSchema
+        | otherwise              -> Right $ TargetIdent $ QualifiedIdentifier pSchema pName
+      PathUnknown -> Right TargetUnknown
+
+  shouldParsePayload = case (contentType, action) of
+    (CTUrlEncoded, ActionInvoke InvPost) -> False
+    (_, act)                             -> act `elem` [ActionCreate, ActionUpdate, ActionSingleUpsert, ActionInvoke InvPost]
+  relevantPayload = case (contentType, action) of
+    -- Though ActionInvoke GET/HEAD doesn't really have a payload, we use the payload variable as a way
+    -- to store the query string arguments to the function.
+    (_, ActionInvoke InvGet)             -> targetToJsonRpcParams (rightToMaybe target) rpcQParams
+    (_, ActionInvoke InvHead)            -> targetToJsonRpcParams (rightToMaybe target) rpcQParams
+    (CTUrlEncoded, ActionInvoke InvPost) -> targetToJsonRpcParams (rightToMaybe target) $ (T.decodeUtf8 *** T.decodeUtf8) <$> parseSimpleQuery (LBS.toStrict reqBody)
+    _ | shouldParsePayload               -> rightToMaybe payload
+      | otherwise                        -> Nothing
+  path =
+    case pathInfo req of
+      []             -> case configDbRootSpec of
+                          Just (QualifiedIdentifier pSch pName)     -> PathInfo (if pSch == mempty then schema else pSch) pName False False True
+                          Nothing | configOpenApiMode == OADisabled -> PathUnknown
+                                  | otherwise                       -> PathInfo schema "" False True False
+      [table]        -> PathInfo schema table False False False
+      ["rpc", pName] -> PathInfo schema pName True False False
+      _              -> PathUnknown
+  method          = requestMethod req
+  hdrs            = requestHeaders req
+  qParams         = [(T.decodeUtf8 k, T.decodeUtf8 <$> v)|(k,v) <- qString]
+  lookupHeader    = flip lookup hdrs
+  Preferences.Preferences{..} = Preferences.fromHeaders hdrs
+  auth = fromMaybe "" $ lookupHeader hAuthorization
+  tokenStr = case T.split (== ' ') (T.decodeUtf8 auth) of
+    ("Bearer" : t : _) -> t
+    ("bearer" : t : _) -> t
+    _                  -> ""
+  endingIn:: [Text] -> Text -> Bool
+  endingIn xx key = lastWord `elem` xx
+    where lastWord = last $ T.split (=='.') key
+
+  headerRange = rangeRequested hdrs
+  replaceLast x s = T.intercalate "." $ L.init (T.split (=='.') s) ++ [x]
+  limitParams :: M.HashMap Text NonnegRange
+  limitParams  = M.fromList [(toS (replaceLast "limit" k), restrictRange (readMaybe =<< v) allRange) | (k,v) <- qParams, isJust v, endingIn ["limit"] k]
+  offsetParams :: M.HashMap Text NonnegRange
+  offsetParams = M.fromList [(toS (replaceLast "limit" k), maybe allRange rangeGeq (readMaybe =<< v)) | (k,v) <- qParams, isJust v, endingIn ["offset"] k]
+
+  urlRange = M.unionWith f limitParams offsetParams
+    where
+      f rl ro = Range (BoundaryBelow o) (BoundaryAbove $ o + l - 1)
+        where
+          l = fromMaybe 0 $ rangeLimit rl
+          o = rangeOffset ro
+  ranges = M.insert "limit" (rangeIntersection headerRange (fromMaybe allRange (M.lookup "limit" urlRange))) urlRange
+
+{-|
+  Find the best match from a list of content types accepted by the
+  client in order of decreasing preference and a list of types
+  producible by the server.  If there is no match but the client
+  accepts */* then return the top server pick.
+-}
+mutuallyAgreeable :: [ContentType] -> [ContentType] -> Maybe ContentType
+mutuallyAgreeable sProduces cAccepts =
+  let exact = listToMaybe $ L.intersect cAccepts sProduces in
+  if isNothing exact && CTAny `elem` cAccepts
+     then listToMaybe sProduces
+     else exact
+
+type CsvData = V.Vector (M.HashMap Text LBS.ByteString)
+
+{-|
+  Converts CSV like
+  a,b
+  1,hi
+  2,bye
+
+  into a JSON array like
+  [ {"a": "1", "b": "hi"}, {"a": 2, "b": "bye"} ]
+
+  The reason for its odd signature is so that it can compose
+  directly with CSV.decodeByName
+-}
+csvToJson :: (CSV.Header, CsvData) -> JSON.Value
+csvToJson (_, vals) =
+  JSON.Array $ V.map rowToJsonObj vals
+ where
+  rowToJsonObj = JSON.Object .
+    M.map (\str ->
+        if str == "NULL"
+          then JSON.Null
+          else JSON.String . T.decodeUtf8 $ LBS.toStrict str
+      )
+
+payloadAttributes :: RequestBody -> JSON.Value -> Maybe Payload
+payloadAttributes raw json =
+  -- Test that Array contains only Objects having the same keys
+  case json of
+    JSON.Array arr ->
+      case arr V.!? 0 of
+        Just (JSON.Object o) ->
+          let canonicalKeys = S.fromList $ M.keys o
+              areKeysUniform = all (\case
+                JSON.Object x -> S.fromList (M.keys x) == canonicalKeys
+                _ -> False) arr in
+          if areKeysUniform
+            then Just $ ProcessedJSON raw canonicalKeys
+            else Nothing
+        Just _ -> Nothing
+        Nothing -> Just emptyPJArray
+
+    JSON.Object o -> Just $ ProcessedJSON raw (S.fromList $ M.keys o)
+
+    -- truncate everything else to an empty array.
+    _ -> Just emptyPJArray
+  where
+    emptyPJArray = ProcessedJSON (JSON.encode emptyArray) S.empty
+
+findAcceptContentType :: AppConfig -> Action -> Path -> [ContentType] -> Either ApiRequestError ContentType
+findAcceptContentType conf action path accepts =
+  case mutuallyAgreeable (requestContentTypes conf action path) accepts of
+    Just ct ->
+      Right ct
+    Nothing ->
+      Left . ContentTypeError $ map ContentType.toMime accepts
+
+requestContentTypes :: AppConfig -> Action -> Path -> [ContentType]
+requestContentTypes conf action path =
+  case action of
+    ActionRead _    -> defaultContentTypes ++ rawContentTypes conf
+    ActionInvoke _  -> invokeContentTypes
+    ActionInspect _ -> [CTOpenAPI, CTApplicationJSON]
+    ActionInfo      -> [CTTextCSV]
+    _               -> defaultContentTypes
+  where
+    invokeContentTypes =
+      defaultContentTypes
+        ++ rawContentTypes conf
+        ++ [CTOpenAPI | pIsRootSpec path]
+    defaultContentTypes =
+      [CTApplicationJSON, CTSingularJSON, CTTextCSV]
+
+rawContentTypes :: AppConfig -> [ContentType]
+rawContentTypes AppConfig{..} =
+  (ContentType.decodeContentType <$> configRawMediaTypes) `union` [CTOctetStream, CTTextPlain]
+
+{-|
+  Search a pg proc by matching name and arguments keys to parameters. Since a function can be overloaded,
+  the name is not enough to find it. An overloaded function can have a different volatility or even a different return type.
+-}
+findProc :: QualifiedIdentifier -> S.Set Text -> Bool -> ProcsMap -> ContentType -> Bool -> Either ApiRequestError ProcDescription
+findProc qi argumentsKeys paramsAsSingleObject allProcs contentType isInvPost =
+  case matchProc of
+    ([], [])     -> Left $ NoRpc (qiSchema qi) (qiName qi) (S.toList argumentsKeys) paramsAsSingleObject contentType isInvPost
+    -- If there are no functions with named arguments, fallback to the single unnamed argument function
+    ([], [proc]) -> Right proc
+    ([], procs)  -> Left $ AmbiguousRpc (toList procs)
+    -- Matches the functions with named arguments
+    ([proc], _)  -> Right proc
+    (procs, _)   -> Left $ AmbiguousRpc (toList procs)
+  where
+    matchProc = overloadedProcPartition $ M.lookupDefault mempty qi allProcs -- first find the proc by name
+    -- The partition obtained has the form (overloadedProcs,fallbackProcs)
+    -- where fallbackProcs are functions with a single unnamed parameter
+    overloadedProcPartition procs = foldr select ([],[]) procs
+    select proc ~(ts,fs)
+      | matchesParams proc         = (proc:ts,fs)
+      | hasSingleUnnamedParam proc = (ts,proc:fs)
+      | otherwise                  = (ts,fs)
+    -- If the function is called with post and has a single unnamed parameter
+    -- it can be called depending on content type and the parameter type
+    hasSingleUnnamedParam proc = isInvPost && case pdParams proc of
+      [ProcParam "" ppType _ _]
+        | contentType == CTApplicationJSON -> ppType `elem` ["json", "jsonb"]
+        | contentType == CTTextPlain       -> ppType == "text"
+        | contentType == CTOctetStream     -> ppType == "bytea"
+        | otherwise                        -> False
+      _ -> False
+    matchesParams proc =
+      let params = pdParams proc in
+      -- exceptional case for Prefer: params=single-object
+      if paramsAsSingleObject
+        then length params == 1 && (ppType <$> headMay params) `elem` [Just "json", Just "jsonb"]
+      -- If the function has no parameters, the arguments keys must be empty as well
+      else if null params
+        then null argumentsKeys && not (isInvPost && contentType `elem` [CTTextPlain, CTOctetStream])
+      -- A function has optional and required parameters. Optional parameters have a default value and
+      -- don't require arguments for the function to be executed, required parameters must have an argument present.
+      else case L.partition ppReq params of
+      -- If the function only has required parameters, the arguments keys must match those parameters
+        (reqParams, [])        -> argumentsKeys == S.fromList (ppName <$> reqParams)
+      -- If the function only has optional parameters, the arguments keys can match none or any of them(a subset)
+        ([], optParams)        -> argumentsKeys `S.isSubsetOf` S.fromList (ppName <$> optParams)
+      -- If the function has required and optional parameters, the arguments keys have to match the required parameters
+      -- and can match any or none of the default parameters.
+        (reqParams, optParams) -> argumentsKeys `S.difference` S.fromList (ppName <$> optParams) == S.fromList (ppName <$> reqParams)
@@ -0,0 +1,397 @@
+{-|
+Module      : PostgREST.Request.DbRequestBuilder
+Description : PostgREST database request builder
+
+This module is in charge of building an intermediate
+representation(ReadRequest, MutateRequest) between the HTTP request and the
+final resulting SQL query.
+
+A query tree is built in case of resource embedding. By inferring the
+relationship between tables, join conditions are added for every embedded
+resource.
+-}
+{-# LANGUAGE DuplicateRecordFields #-}
+{-# LANGUAGE LambdaCase            #-}
+{-# LANGUAGE NamedFieldPuns        #-}
+{-# LANGUAGE RecordWildCards       #-}
+
+module PostgREST.Request.DbRequestBuilder
+  ( readRequest
+  , mutateRequest
+  , callRequest
+  ) where
+
+import qualified Data.HashMap.Strict as M
+import qualified Data.Set            as S
+
+import Control.Arrow           ((***))
+import Data.Either.Combinators (mapLeft)
+import Data.List               (delete)
+import Data.Text               (isInfixOf)
+import Data.Tree               (Tree (..))
+
+import PostgREST.DbStructure.Identifiers  (FieldName,
+                                           QualifiedIdentifier (..),
+                                           Schema, TableName)
+import PostgREST.DbStructure.Proc         (ProcDescription (..),
+                                           ProcParam (..),
+                                           procReturnsScalar)
+import PostgREST.DbStructure.Relationship (Cardinality (..),
+                                           Junction (..),
+                                           Relationship (..))
+import PostgREST.DbStructure.Table        (Column (..), Table (..),
+                                           tableQi)
+import PostgREST.Error                    (ApiRequestError (..),
+                                           Error (..))
+import PostgREST.Query.SqlFragment        (sourceCTEName)
+import PostgREST.RangeQuery               (NonnegRange, allRange,
+                                           restrictRange)
+import PostgREST.Request.ApiRequest       (Action (..),
+                                           ApiRequest (..),
+                                           Payload (..))
+
+import PostgREST.Request.Parsers
+import PostgREST.Request.Preferences
+import PostgREST.Request.Types
+
+import qualified PostgREST.DbStructure.Relationship as Relationship
+
+import Protolude hiding (from, isInfixOf)
+
+-- | Builds the ReadRequest tree on a number of stages.
+-- | Adds filters, order, limits on its respective nodes.
+-- | Adds joins conditions obtained from resource embedding.
+readRequest :: Schema -> TableName -> Maybe Integer -> [Relationship] -> ApiRequest -> Either Error ReadRequest
+readRequest schema rootTableName maxRows allRels apiRequest  =
+  mapLeft ApiRequestError $
+  treeRestrictRange maxRows =<<
+  augmentRequestWithJoin schema rootRels =<<
+  (addFiltersOrdersRanges apiRequest . initReadRequest rootName =<< pRequestSelect sel)
+  where
+    sel = fromMaybe "*" $ iSelect apiRequest -- default to all columns requested (SELECT *) for a non existent ?select querystring param
+    (rootName, rootRels) = rootWithRels schema rootTableName allRels (iAction apiRequest)
+
+-- Get the root table name with its relationships according to the Action type.
+-- This is done because of the shape of the final SQL Query. The mutation cases
+-- are wrapped in a WITH {sourceCTEName}(see Statements.hs).  So we need a FROM
+-- {sourceCTEName} instead of FROM {tableName}.
+rootWithRels :: Schema -> TableName -> [Relationship] -> Action -> (QualifiedIdentifier, [Relationship])
+rootWithRels schema rootTableName allRels action = case action of
+  ActionRead _ -> (QualifiedIdentifier schema rootTableName, allRels) -- normal read case
+  _            -> (QualifiedIdentifier mempty _sourceCTEName, mapMaybe toSourceRel allRels ++ allRels) -- mutation cases and calling proc
+  where
+    _sourceCTEName = decodeUtf8 sourceCTEName
+    -- To enable embedding in the sourceCTEName cases we need to replace the
+    -- foreign key tableName in the Relationship with {sourceCTEName}. This way
+    -- findRel can find relationships with sourceCTEName.
+    toSourceRel :: Relationship -> Maybe Relationship
+    toSourceRel r@Relationship{relTable=t}
+      | rootTableName == tableName t = Just $ r {relTable=t {tableName=_sourceCTEName}}
+      | otherwise                    = Nothing
+
+-- Build the initial tree with a Depth attribute so when a self join occurs we
+-- can differentiate the parent and child tables by having an alias like
+-- "table_depth", this is related to
+-- http://github.com/PostgREST/postgrest/issues/987.
+initReadRequest :: QualifiedIdentifier -> [Tree SelectItem] -> ReadRequest
+initReadRequest rootQi =
+  foldr (treeEntry rootDepth) initial
+  where
+    rootDepth = 0
+    rootSchema = qiSchema rootQi
+    rootName = qiName rootQi
+    initial = Node (Select [] rootQi Nothing [] [] [] [] allRange, (rootName, Nothing, Nothing, Nothing, Nothing, rootDepth)) []
+    treeEntry :: Depth -> Tree SelectItem -> ReadRequest -> ReadRequest
+    treeEntry depth (Node fld@((fn, _),_,alias, hint, joinType) fldForest) (Node (q, i) rForest) =
+      let nxtDepth = succ depth in
+      case fldForest of
+        [] -> Node (q {select=fld:select q}, i) rForest
+        _  -> Node (q, i) $
+              foldr (treeEntry nxtDepth)
+              (Node (Select [] (QualifiedIdentifier rootSchema fn) Nothing [] [] [] [] allRange,
+                (fn, Nothing, alias, hint, joinType, nxtDepth)) [])
+              fldForest:rForest
+
+-- | Enforces the `max-rows` config on the result
+treeRestrictRange :: Maybe Integer -> ReadRequest -> Either ApiRequestError ReadRequest
+treeRestrictRange maxRows request = pure $ nodeRestrictRange maxRows <$> request
+  where
+    nodeRestrictRange :: Maybe Integer -> ReadNode -> ReadNode
+    nodeRestrictRange m (q@Select {range_=r}, i) = (q{range_=restrictRange m r }, i)
+
+augmentRequestWithJoin :: Schema -> [Relationship] -> ReadRequest -> Either ApiRequestError ReadRequest
+augmentRequestWithJoin schema allRels request =
+  addRels schema allRels Nothing request
+  >>= addJoinConditions Nothing
+
+addRels :: Schema -> [Relationship] -> Maybe ReadRequest -> ReadRequest -> Either ApiRequestError ReadRequest
+addRels schema allRels parentNode (Node (query@Select{from=tbl}, (nodeName, _, alias, hint, joinType, depth)) forest) =
+  case parentNode of
+    Just (Node (Select{from=parentNodeQi}, _) _) ->
+      let newFrom r = if qiName tbl == nodeName then tableQi (relForeignTable r) else tbl
+          newReadNode = (\r -> (query{from=newFrom r}, (nodeName, Just r, alias, hint, joinType, depth))) <$> rel
+          rel = findRel schema allRels (qiName parentNodeQi) nodeName hint
+      in
+      Node <$> newReadNode <*> (updateForest . hush $ Node <$> newReadNode <*> pure forest)
+    _ ->
+      let rn = (query, (nodeName, Nothing, alias, Nothing, joinType, depth)) in
+      Node rn <$> updateForest (Just $ Node rn forest)
+  where
+    updateForest :: Maybe ReadRequest -> Either ApiRequestError [ReadRequest]
+    updateForest rq = addRels schema allRels rq `traverse` forest
+
+-- Finds a relationship between an origin and a target in the request:
+-- /origin?select=target(*) If more than one relationship is found then the
+-- request is ambiguous and we return an error.  In that case the request can
+-- be disambiguated by adding precision to the target or by using a hint:
+-- /origin?select=target!hint(*) The elements will be matched according to
+-- these rules:
+-- origin = table / view
+-- target = table / view / constraint / column-from-origin
+-- hint   = table / view / constraint / column-from-origin / column-from-target
+-- (hint can take table / view values to aid in finding the junction in an m2m relationship)
+findRel :: Schema -> [Relationship] -> NodeName -> NodeName -> Maybe Hint -> Either ApiRequestError Relationship
+findRel schema allRels origin target hint =
+  case rel of
+    []  -> Left $ NoRelBetween origin target
+    [r] -> Right r
+    -- Here we handle a self reference relationship to not cause a breaking
+    -- change: In a self reference we get two relationships with the same
+    -- foreign key and relTable/relFtable but with different
+    -- cardinalities(m2o/o2m) We output the O2M rel, the M2O rel can be
+    -- obtained by using the origin column as an embed hint.
+    rs@[rel0, rel1]  -> case (relCardinality rel0, relCardinality rel1, relTable rel0 == relTable rel1 && relForeignTable rel0 == relForeignTable rel1) of
+      (O2M cons1, M2O cons2, True) -> if cons1 == cons2 then Right rel0 else Left $ AmbiguousRelBetween origin target rs
+      (M2O cons1, O2M cons2, True) -> if cons1 == cons2 then Right rel1 else Left $ AmbiguousRelBetween origin target rs
+      _                            -> Left $ AmbiguousRelBetween origin target rs
+    rs -> Left $ AmbiguousRelBetween origin target rs
+  where
+    matchFKSingleCol hint_ cols = length cols == 1 && hint_ == (colName <$> head cols)
+    matchConstraint tar card = case card of
+      O2M cons -> tar == Just cons
+      M2O cons -> tar == Just cons
+      _        -> False
+    matchJunction hint_ card = case card of
+      M2M Junction{junTable} -> hint_ == Just (tableName junTable)
+      _                      -> False
+    rel = filter (
+      \Relationship{..} ->
+        -- Both relationship ends need to be on the exposed schema
+        schema == tableSchema relTable && schema == tableSchema relForeignTable &&
+        (
+          -- /projects?select=clients(*)
+          origin == tableName relTable  &&  -- projects
+          target == tableName relForeignTable ||  -- clients
+
+          -- /projects?select=projects_client_id_fkey(*)
+          (
+            origin == tableName relTable &&              -- projects
+            matchConstraint (Just target) relCardinality -- projects_client_id_fkey
+          ) ||
+          -- /projects?select=client_id(*)
+          (
+            origin == tableName relTable &&           -- projects
+            matchFKSingleCol (Just target) relColumns -- client_id
+          )
+        ) && (
+          isNothing hint || -- hint is optional
+
+          -- /projects?select=clients!projects_client_id_fkey(*)
+          matchConstraint hint relCardinality || -- projects_client_id_fkey
+
+          -- /projects?select=clients!client_id(*) or /projects?select=clients!id(*)
+          matchFKSingleCol hint relColumns  || -- client_id
+          matchFKSingleCol hint relForeignColumns || -- id
+
+          -- /users?select=tasks!users_tasks(*) many-to-many between users and tasks
+          matchJunction hint relCardinality -- users_tasks
+        )
+      ) allRels
+
+-- previousAlias is only used for the case of self joins
+addJoinConditions :: Maybe Alias -> ReadRequest -> Either ApiRequestError ReadRequest
+addJoinConditions previousAlias (Node node@(query@Select{from=tbl}, nodeProps@(_, rel, _, _, _, depth)) forest) =
+  case rel of
+    Just r@Relationship{relCardinality=M2M Junction{junTable}} ->
+      let rq = augmentQuery r in
+      Node (rq{implicitJoins=tableQi junTable:implicitJoins rq}, nodeProps) <$> updatedForest
+    Just r -> Node (augmentQuery r, nodeProps) <$> updatedForest
+    Nothing -> Node node <$> updatedForest
+  where
+    newAlias = case Relationship.isSelfReference <$> rel of
+      Just True
+        | depth /= 0 -> Just (qiName tbl <> "_" <> show depth) -- root node doesn't get aliased
+        | otherwise  -> Nothing
+      _              -> Nothing
+    augmentQuery r =
+      foldr
+        (\jc rq@Select{joinConditions=jcs} -> rq{joinConditions=jc:jcs})
+        query{fromAlias=newAlias}
+        (getJoinConditions previousAlias newAlias r)
+    updatedForest = addJoinConditions newAlias `traverse` forest
+
+-- previousAlias and newAlias are used in the case of self joins
+getJoinConditions :: Maybe Alias -> Maybe Alias -> Relationship -> [JoinCondition]
+getJoinConditions previousAlias newAlias (Relationship Table{tableSchema=tSchema, tableName=tN} cols Table{tableName=ftN} fCols card) =
+  case card of
+    M2M (Junction Table{tableName=jtn} _ jc1 _ jc2) ->
+      zipWith (toJoinCondition tN jtn) cols jc1 ++ zipWith (toJoinCondition ftN jtn) fCols jc2
+    _ ->
+      zipWith (toJoinCondition tN ftN) cols fCols
+  where
+    toJoinCondition :: Text -> Text -> Column -> Column -> JoinCondition
+    toJoinCondition tb ftb c fc =
+      let qi1 = removeSourceCTESchema tSchema tb
+          qi2 = removeSourceCTESchema tSchema ftb in
+        JoinCondition (maybe qi1 (QualifiedIdentifier mempty) previousAlias, colName c)
+                      (maybe qi2 (QualifiedIdentifier mempty) newAlias, colName fc)
+
+    -- On mutation and calling proc cases we wrap the target table in a WITH
+    -- {sourceCTEName} if this happens remove the schema `FROM
+    -- "schema"."{sourceCTEName}"` and use only the `FROM "{sourceCTEName}"`.
+    -- If the schema remains the FROM would be invalid.
+    removeSourceCTESchema :: Schema -> TableName -> QualifiedIdentifier
+    removeSourceCTESchema schema tbl = QualifiedIdentifier (if tbl == decodeUtf8 sourceCTEName then mempty else schema) tbl
+
+addFiltersOrdersRanges :: ApiRequest -> ReadRequest -> Either ApiRequestError ReadRequest
+addFiltersOrdersRanges apiRequest rReq = do
+  rFlts <- foldr addFilter rReq <$> filters
+  rOrds <- foldr addOrder rFlts <$> orders
+  rRngs <- foldr addRange rOrds <$> ranges
+  foldr addLogicTree rRngs      <$> logicForest
+  where
+    filters :: Either ApiRequestError [(EmbedPath, Filter)]
+    filters = pRequestFilter `traverse` flts
+    orders :: Either ApiRequestError [(EmbedPath, [OrderTerm])]
+    orders = pRequestOrder `traverse` iOrder apiRequest
+    ranges :: Either ApiRequestError [(EmbedPath, NonnegRange)]
+    ranges = pRequestRange `traverse` M.toList (iRange apiRequest)
+    logicForest :: Either ApiRequestError [(EmbedPath, LogicTree)]
+    logicForest = pRequestLogicTree `traverse` logFrst
+    action = iAction apiRequest
+    -- there can be no filters on the root table when we are doing insert/update/delete
+    (flts, logFrst) =
+      case action of
+        ActionInvoke _ -> (iFilters apiRequest, iLogic apiRequest)
+        ActionRead _   -> (iFilters apiRequest, iLogic apiRequest)
+        _              -> join (***) (filter (( "." `isInfixOf` ) . fst)) (iFilters apiRequest, iLogic apiRequest)
+
+addFilterToNode :: Filter -> ReadRequest -> ReadRequest
+addFilterToNode flt (Node (q@Select {where_=lf}, i) f) = Node (q{where_=addFilterToLogicForest flt lf}::ReadQuery, i) f
+
+addFilter :: (EmbedPath, Filter) -> ReadRequest -> ReadRequest
+addFilter = addProperty addFilterToNode
+
+addOrderToNode :: [OrderTerm] -> ReadRequest -> ReadRequest
+addOrderToNode o (Node (q,i) f) = Node (q{order=o}, i) f
+
+addOrder :: (EmbedPath, [OrderTerm]) -> ReadRequest -> ReadRequest
+addOrder = addProperty addOrderToNode
+
+addRangeToNode :: NonnegRange -> ReadRequest -> ReadRequest
+addRangeToNode r (Node (q,i) f) = Node (q{range_=r}, i) f
+
+addRange :: (EmbedPath, NonnegRange) -> ReadRequest -> ReadRequest
+addRange = addProperty addRangeToNode
+
+addLogicTreeToNode :: LogicTree -> ReadRequest -> ReadRequest
+addLogicTreeToNode t (Node (q@Select{where_=lf},i) f) = Node (q{where_=t:lf}::ReadQuery, i) f
+
+addLogicTree :: (EmbedPath, LogicTree) -> ReadRequest -> ReadRequest
+addLogicTree = addProperty addLogicTreeToNode
+
+addProperty :: (a -> ReadRequest -> ReadRequest) -> (EmbedPath, a) -> ReadRequest -> ReadRequest
+addProperty f ([], a) rr = f a rr
+addProperty f (targetNodeName:remainingPath, a) (Node rn forest) =
+  case pathNode of
+    Nothing -> Node rn forest -- the property is silenty dropped in the Request does not contain the required path
+    Just tn -> Node rn (addProperty f (remainingPath, a) tn:delete tn forest)
+  where
+    pathNode = find (\(Node (_,(nodeName,_,alias,_,_, _)) _) -> nodeName == targetNodeName || alias == Just targetNodeName) forest
+
+mutateRequest :: Schema -> TableName -> ApiRequest -> [FieldName] -> ReadRequest -> Either Error MutateRequest
+mutateRequest schema tName apiRequest pkCols readReq = mapLeft ApiRequestError $
+  case action of
+    ActionCreate -> do
+        confCols <- case iOnConflict apiRequest of
+            Nothing    -> pure pkCols
+            Just param -> pRequestOnConflict param
+        pure $ Insert qi (iColumns apiRequest) body ((,) <$> iPreferResolution apiRequest <*> Just confCols) [] returnings
+    ActionUpdate -> Update qi (iColumns apiRequest) body  <$> combinedLogic <*> pure returnings
+    ActionSingleUpsert ->
+      (\flts ->
+        if null (iLogic apiRequest) &&
+           S.fromList (fst <$> iFilters apiRequest) == S.fromList pkCols &&
+           not (null (S.fromList pkCols)) &&
+           all (\case
+              Filter _ (OpExpr False (Op "eq" _)) -> True
+              _                                   -> False) flts
+          then Insert qi (iColumns apiRequest) body (Just (MergeDuplicates, pkCols)) <$> combinedLogic <*> pure returnings
+        else
+          Left InvalidFilters) =<< filters
+    ActionDelete -> Delete qi <$> combinedLogic <*> pure returnings
+    _            -> Left UnsupportedVerb
+  where
+    qi = QualifiedIdentifier schema tName
+    action = iAction apiRequest
+    returnings =
+      if iPreferRepresentation apiRequest == None
+        then []
+        else returningCols readReq pkCols
+    filters = map snd <$> pRequestFilter `traverse` mutateFilters
+    logic = map snd <$> pRequestLogicTree `traverse` logicFilters
+    combinedLogic = foldr addFilterToLogicForest <$> logic <*> filters
+    -- update/delete filters can be only on the root table
+    (mutateFilters, logicFilters) = join (***) onlyRoot (iFilters apiRequest, iLogic apiRequest)
+    onlyRoot = filter (not . ( "." `isInfixOf` ) . fst)
+    body = payRaw <$> iPayload apiRequest -- the body is assumed to be json at this stage(ApiRequest validates)
+
+callRequest :: ProcDescription -> ApiRequest -> ReadRequest -> CallRequest
+callRequest proc apiReq readReq = FunctionCall {
+  funCQi = QualifiedIdentifier (pdSchema proc) (pdName proc)
+, funCParams = callParams
+, funCArgs = payRaw <$> iPayload apiReq
+, funCScalar = procReturnsScalar proc
+, funCMultipleCall = iPreferParameters apiReq == Just MultipleObjects
+, funCReturning = returningCols readReq []
+}
+  where
+    paramsAsSingleObject = iPreferParameters apiReq == Just SingleObject
+    callParams = case pdParams proc of
+      [prm] | paramsAsSingleObject -> OnePosParam prm
+            | ppName prm == mempty -> OnePosParam prm
+            | otherwise            -> KeyParams $ specifiedParams [prm]
+      prms  -> KeyParams $ specifiedParams prms
+    specifiedParams params = filter (\x -> ppName x `S.member` iColumns apiReq) params
+
+returningCols :: ReadRequest -> [FieldName] -> [FieldName]
+returningCols rr@(Node _ forest) pkCols
+  -- if * is part of the select, we must not add pk or fk columns manually -
+  -- otherwise those would be selected and output twice
+  | "*" `elem` fldNames = ["*"]
+  | otherwise           = returnings
+  where
+    fldNames = fstFieldNames rr
+    -- Without fkCols, when a mutateRequest to
+    -- /projects?select=name,clients(name) occurs, the RETURNING SQL part would
+    -- be `RETURNING name`(see QueryBuilder).  This would make the embedding
+    -- fail because the following JOIN would need the "client_id" column from
+    -- projects.  So this adds the foreign key columns to ensure the embedding
+    -- succeeds, result would be `RETURNING name, client_id`.
+    fkCols = concat $ mapMaybe (\case
+        Node (_, (_, Just Relationship{relColumns=cols}, _, _, _, _)) _ -> Just cols
+        _                                                        -> Nothing
+      ) forest
+    -- However if the "client_id" is present, e.g. mutateRequest to
+    -- /projects?select=client_id,name,clients(name) we would get `RETURNING
+    -- client_id, name, client_id` and then we would produce the "column
+    -- reference \"client_id\" is ambiguous" error from PostgreSQL. So we
+    -- deduplicate with Set: We are adding the primary key columns as well to
+    -- make sure, that a proper location header can always be built for
+    -- INSERT/POST
+    returnings = S.toList . S.fromList $ fldNames ++ (colName <$> fkCols) ++ pkCols
+
+-- Traditional filters(e.g. id=eq.1) are added as root nodes of the LogicTree
+-- they are later concatenated with AND in the QueryBuilder
+addFilterToLogicForest :: Filter -> [LogicTree] -> [LogicTree]
+addFilterToLogicForest flt lf = Stmnt flt : lf
@@ -0,0 +1,300 @@
+{-|
+Module      : PostgREST.Request.Parsers
+Description : PostgREST parser combinators
+
+This module is in charge of parsing all the querystring values in an url, e.g. the select, id, order in `/projects?select=id,name&id=eq.1&order=id,name.desc`.
+-}
+module PostgREST.Request.Parsers
+  ( pColumns
+  , pLogicPath
+  , pLogicSingleVal
+  , pLogicTree
+  , pOrder
+  , pOrderTerm
+  , pRequestColumns
+  , pRequestFilter
+  , pRequestLogicTree
+  , pRequestOnConflict
+  , pRequestOrder
+  , pRequestRange
+  , pRequestSelect
+  , pSingleVal
+  , pTreePath
+  ) where
+
+import qualified Data.HashMap.Strict as M
+import qualified Data.Set            as S
+
+import Data.Either.Combinators       (mapLeft)
+import Data.Foldable                 (foldl1)
+import Data.List                     (init, last)
+import Data.Text                     (intercalate, replace, strip)
+import Data.Tree                     (Tree (..))
+import Text.Parsec.Error             (errorMessages,
+                                      showErrorMessages)
+import Text.ParserCombinators.Parsec (GenParser, ParseError, Parser,
+                                      anyChar, between, char, digit,
+                                      eof, errorPos, letter,
+                                      lookAhead, many1, noneOf,
+                                      notFollowedBy, oneOf, option,
+                                      optionMaybe, parse, sepBy1,
+                                      string, try, (<?>))
+
+import PostgREST.DbStructure.Identifiers (FieldName)
+import PostgREST.Error                   (ApiRequestError (ParseRequestError))
+import PostgREST.Query.SqlFragment       (ftsOperators, operators)
+import PostgREST.RangeQuery              (NonnegRange)
+
+import PostgREST.Request.Types
+
+import Protolude hiding (intercalate, option, replace, try)
+
+pRequestSelect :: Text -> Either ApiRequestError [Tree SelectItem]
+pRequestSelect selStr =
+  mapError $ parse pFieldForest ("failed to parse select parameter (" <> toS selStr <> ")") (toS selStr)
+
+pRequestOnConflict :: Text -> Either ApiRequestError  [FieldName]
+pRequestOnConflict oncStr =
+  mapError $ parse pColumns ("failed to parse on_conflict parameter (" <> toS oncStr <> ")") (toS oncStr)
+
+pRequestFilter :: (Text, Text) -> Either ApiRequestError (EmbedPath, Filter)
+pRequestFilter (k, v) = mapError $ (,) <$> path <*> (Filter <$> fld <*> oper)
+  where
+    treePath = parse pTreePath ("failed to parser tree path (" ++ toS k ++ ")") $ toS k
+    oper = parse (pOpExpr pSingleVal) ("failed to parse filter (" ++ toS v ++ ")") $ toS v
+    path = fst <$> treePath
+    fld = snd <$> treePath
+
+pRequestOrder :: (Text, Text) -> Either ApiRequestError (EmbedPath, [OrderTerm])
+pRequestOrder (k, v) = mapError $ (,) <$> path <*> ord'
+  where
+    treePath = parse pTreePath ("failed to parser tree path (" ++ toS k ++ ")") $ toS k
+    path = fst <$> treePath
+    ord' = parse pOrder ("failed to parse order (" ++ toS v ++ ")") $ toS v
+
+pRequestRange :: (Text, NonnegRange) -> Either ApiRequestError (EmbedPath, NonnegRange)
+pRequestRange (k, v) = mapError $ (,) <$> path <*> pure v
+  where
+    treePath = parse pTreePath ("failed to parser tree path (" ++ toS k ++ ")") $ toS k
+    path = fst <$> treePath
+
+pRequestLogicTree :: (Text, Text) -> Either ApiRequestError (EmbedPath, LogicTree)
+pRequestLogicTree (k, v) = mapError $ (,) <$> embedPath <*> logicTree
+  where
+    path = parse pLogicPath ("failed to parser logic path (" ++ toS k ++ ")") $ toS k
+    embedPath = fst <$> path
+    logicTree = do
+      op <- snd <$> path
+      -- Concat op and v to make pLogicTree argument regular,
+      -- in the form of "?and=and(.. , ..)" instead of "?and=(.. , ..)"
+      parse pLogicTree ("failed to parse logic tree (" ++ toS v ++ ")") $ toS (op <> v)
+
+pRequestColumns :: Maybe Text -> Either ApiRequestError (Maybe (S.Set FieldName))
+pRequestColumns colStr =
+  case colStr of
+    Just str ->
+      mapError $ Just . S.fromList <$> parse pColumns ("failed to parse columns parameter (" <> toS str <> ")") (toS str)
+    _ -> Right Nothing
+
+ws :: Parser Text
+ws = toS <$> many (oneOf " \t")
+
+lexeme :: Parser a -> Parser a
+lexeme p = ws *> p <* ws
+
+pTreePath :: Parser (EmbedPath, Field)
+pTreePath = do
+  p <- pFieldName `sepBy1` pDelimiter
+  jp <- option [] pJsonPath
+  return (init p, (last p, jp))
+
+pFieldForest :: Parser [Tree SelectItem]
+pFieldForest = pFieldTree `sepBy1` lexeme (char ',')
+  where
+    pFieldTree :: Parser (Tree SelectItem)
+    pFieldTree =  try (Node <$> pRelationSelect <*> between (char '(') (char ')') pFieldForest) <|>
+                  Node <$> pFieldSelect <*> pure []
+
+pStar :: Parser Text
+pStar = string "*" $> "*"
+
+pFieldName :: Parser Text
+pFieldName =
+  pQuotedValue <|>
+  intercalate "-" . map toS <$> (many1 (letter <|> digit <|> oneOf "_ ") `sepBy1` dash) <?>
+  "field name (* or [a..z0..9_])"
+  where
+    isDash :: GenParser Char st ()
+    isDash = try ( char '-' >> notFollowedBy (char '>') )
+    dash :: Parser Char
+    dash = isDash $> '-'
+
+pJsonPath :: Parser JsonPath
+pJsonPath = many pJsonOperation
+  where
+    pJsonOperation :: Parser JsonOperation
+    pJsonOperation = pJsonArrow <*> pJsonOperand
+
+    pJsonArrow   =
+      try (string "->>" $> J2Arrow) <|>
+      try (string "->" $> JArrow)
+
+    pJsonOperand =
+      let pJKey = JKey . toS <$> pFieldName
+          pJIdx = JIdx . toS <$> ((:) <$> option '+' (char '-') <*> many1 digit) <* pEnd
+          pEnd = try (void $ lookAhead (string "->")) <|>
+                 try (void $ lookAhead (string "::")) <|>
+                 try eof in
+      try pJIdx <|> try pJKey
+
+pField :: Parser Field
+pField = lexeme $ (,) <$> pFieldName <*> option [] pJsonPath
+
+aliasSeparator :: Parser ()
+aliasSeparator = char ':' >> notFollowedBy (char ':')
+
+pRelationSelect :: Parser SelectItem
+pRelationSelect = lexeme $ try ( do
+    alias <- optionMaybe ( try(pFieldName <* aliasSeparator) )
+    fld <- pField
+    prm1 <- optionMaybe pEmbedParam
+    prm2 <- optionMaybe pEmbedParam
+    return (fld, Nothing, alias, embedParamHint prm1 <|> embedParamHint prm2, embedParamJoin prm1 <|> embedParamJoin prm2)
+  )
+  where
+    pEmbedParam :: Parser EmbedParam
+    pEmbedParam =
+      char '!' *> (
+        try (string "left"  $> EPJoinType JTLeft)  <|>
+        try (string "inner" $> EPJoinType JTInner) <|>
+        try (EPHint <$> pFieldName))
+    embedParamHint prm = case prm of
+      Just (EPHint hint) -> Just hint
+      _                  -> Nothing
+    embedParamJoin prm = case prm of
+      Just (EPJoinType jt) -> Just jt
+      _                    -> Nothing
+
+pFieldSelect :: Parser SelectItem
+pFieldSelect = lexeme $
+  try (
+    do
+      alias <- optionMaybe ( try(pFieldName <* aliasSeparator) )
+      fld <- pField
+      cast' <- optionMaybe (string "::" *> many letter)
+      return (fld, toS <$> cast', alias, Nothing, Nothing)
+  )
+  <|> do
+    s <- pStar
+    return ((s, []), Nothing, Nothing, Nothing, Nothing)
+
+pOpExpr :: Parser SingleVal -> Parser OpExpr
+pOpExpr pSVal = try ( string "not" *> pDelimiter *> (OpExpr True <$> pOperation)) <|> OpExpr False <$> pOperation
+  where
+    pOperation :: Parser Operation
+    pOperation =
+          Op . toS <$> foldl1 (<|>) (try . ((<* pDelimiter) . string) . toS <$> M.keys ops) <*> pSVal
+      <|> In <$> (try (string "in" *> pDelimiter) *> pListVal)
+      <|> Is <$> (try (string "is" *> pDelimiter) *> pTriVal)
+      <|> pFts
+      <?> "operator (eq, gt, ...)"
+
+    pTriVal = try (ciString "null"    $> TriNull)
+          <|> try (ciString "unknown" $> TriUnknown)
+          <|> try (ciString "true"    $> TriTrue)
+          <|> try (ciString "false"   $> TriFalse)
+          <?> "null or trilean value (unknown, true, false)"
+
+    pFts = do
+      op   <- foldl1 (<|>) (try . string . toS <$> ftsOps)
+      lang <- optionMaybe $ try (between (char '(') (char ')') (many (letter <|> digit <|> oneOf "_")))
+      pDelimiter >> Fts (toS op) (toS <$> lang) <$> pSVal
+
+    ops = M.filterWithKey (const . flip notElem ("in":"is":ftsOps)) operators
+    ftsOps = M.keys ftsOperators
+
+    -- case insensitive char and string
+    ciChar :: Char -> GenParser Char state Char
+    ciChar c = char c <|> char (toUpper c)
+    ciString :: [Char] -> GenParser Char state [Char]
+    ciString = traverse ciChar
+
+pSingleVal :: Parser SingleVal
+pSingleVal = toS <$> many anyChar
+
+pListVal :: Parser ListVal
+pListVal = lexeme (char '(') *> pListElement `sepBy1` char ',' <* lexeme (char ')')
+
+pListElement :: Parser Text
+pListElement = try (pQuotedValue <* notFollowedBy (noneOf ",)")) <|> (toS <$> many (noneOf ",)"))
+
+pQuotedValue :: Parser Text
+pQuotedValue = toS <$> (char '"' *> many pCharsOrSlashed <* char '"')
+  where
+    pCharsOrSlashed = noneOf "\\\"" <|> (char '\\' *> anyChar)
+
+pDelimiter :: Parser Char
+pDelimiter = char '.' <?> "delimiter (.)"
+
+pOrder :: Parser [OrderTerm]
+pOrder = lexeme pOrderTerm `sepBy1` char ','
+
+pOrderTerm :: Parser OrderTerm
+pOrderTerm = do
+  fld <- pField
+  dir <- optionMaybe $
+         try (pDelimiter *> string "asc" $> OrderAsc) <|>
+         try (pDelimiter *> string "desc" $> OrderDesc)
+  nls <- optionMaybe pNulls <* pEnd <|>
+         pEnd $> Nothing
+  return $ OrderTerm fld dir nls
+  where
+    pNulls = try (pDelimiter *> string "nullsfirst" $> OrderNullsFirst) <|>
+             try (pDelimiter *> string "nullslast"  $> OrderNullsLast)
+    pEnd = try (void $ lookAhead (char ',')) <|>
+           try eof
+
+pLogicTree :: Parser LogicTree
+pLogicTree = Stmnt <$> try pLogicFilter
+             <|> Expr <$> pNot <*> pLogicOp <*> (lexeme (char '(') *> pLogicTree `sepBy1` lexeme (char ',') <* lexeme (char ')'))
+  where
+    pLogicFilter :: Parser Filter
+    pLogicFilter = Filter <$> pField <* pDelimiter <*> pOpExpr pLogicSingleVal
+    pNot :: Parser Bool
+    pNot = try (string "not" *> pDelimiter $> True)
+           <|> pure False
+           <?> "negation operator (not)"
+    pLogicOp :: Parser LogicOperator
+    pLogicOp = try (string "and" $> And)
+               <|> string "or" $> Or
+               <?> "logic operator (and, or)"
+
+pLogicSingleVal :: Parser SingleVal
+pLogicSingleVal = try (pQuotedValue <* notFollowedBy (noneOf ",)")) <|> try pPgArray <|> (toS <$> many (noneOf ",)"))
+  where
+    pPgArray :: Parser Text
+    pPgArray =  do
+      a <- string "{"
+      b <- many (noneOf "{}")
+      c <- string "}"
+      pure (toS $ a ++ b ++ c)
+
+pLogicPath :: Parser (EmbedPath, Text)
+pLogicPath = do
+  path <- pFieldName `sepBy1` pDelimiter
+  let op = last path
+      notOp = "not." <> op
+  return (filter (/= "not") (init path), if "not" `elem` path then notOp else op)
+
+pColumns :: Parser [FieldName]
+pColumns = pFieldName `sepBy1` lexeme (char ',')
+
+mapError :: Either ParseError a -> Either ApiRequestError a
+mapError = mapLeft translateError
+  where
+    translateError e =
+      ParseRequestError message details
+      where
+        message = show $ errorPos e
+        details = strip $ replace "\n" " " $ toS
+           $ showErrorMessages "or" "unknown parse error" "expecting" "unexpected" "end of input" (errorMessages e)
@@ -1,23 +1,20 @@
 -- |
-- Module: PostgREST.ApiRequest.Preferences
+-- Module: PostgREST.Request.Preferences
 -- Description: Track client preferences to be employed when processing requests
 --
 -- Track client prefences set in HTTP 'Prefer' headers according to RFC7240[1].
 --
 -- [1] https://datatracker.ietf.org/doc/html/rfc7240
 --
-{-# LANGUAGE NamedFieldPuns #-}
-module PostgREST.ApiRequest.Preferences
+module PostgREST.Request.Preferences
  ( Preferences(..)
  , PreferCount(..)
-  , PreferMissing(..)
  , PreferParameters(..)
  , PreferRepresentation(..)
  , PreferResolution(..)
  , PreferTransaction(..)
  , fromHeaders
-  , shouldCount
-  , prefAppliedHeader
+  , ToAppliedHeader(..)
  ) where

 import qualified Data.ByteString.Char8     as BS
@@ -35,7 +32,6 @@ import Protolude
 -- >>> deriving instance Show PreferParameters
 -- >>> deriving instance Show PreferCount
 -- >>> deriving instance Show PreferTransaction
-- >>> deriving instance Show PreferMissing
 -- >>> deriving instance Show Preferences

 -- | Preferences recognized by the application.
@@ -46,7 +42,6 @@ data Preferences
    , preferParameters     :: Maybe PreferParameters
    , preferCount          :: Maybe PreferCount
    , preferTransaction    :: Maybe PreferTransaction
-    , preferMissing        :: Maybe PreferMissing
    }

 -- |
@@ -54,37 +49,35 @@ data Preferences
 --
 -- One header with comma-separated values can be used to set multiple preferences:
 --
-- >>> pPrint $ fromHeaders True [("Prefer", "resolution=ignore-duplicates, count=exact")]
+-- >>> pPrint $ fromHeaders [("Prefer", "resolution=ignore-duplicates, count=exact")]
 -- Preferences
 --     { preferResolution = Just IgnoreDuplicates
 --     , preferRepresentation = Nothing
 --     , preferParameters = Nothing
 --     , preferCount = Just ExactCount
 --     , preferTransaction = Nothing
--     , preferMissing = Nothing
 --     }
 --
 -- Multiple headers can also be used:
 --
-- >>> pPrint $ fromHeaders True [("Prefer", "resolution=ignore-duplicates"), ("Prefer", "count=exact"), ("Prefer", "missing=null")]
+-- >>> pPrint $ fromHeaders [("Prefer", "resolution=ignore-duplicates"), ("Prefer", "count=exact")]
 -- Preferences
 --     { preferResolution = Just IgnoreDuplicates
 --     , preferRepresentation = Nothing
 --     , preferParameters = Nothing
 --     , preferCount = Just ExactCount
 --     , preferTransaction = Nothing
--     , preferMissing = Just ApplyNulls
 --     }
 --
 -- If a preference is set more than once, only the first is used:
 --
-- >>> preferTransaction $ fromHeaders True [("Prefer", "tx=commit, tx=rollback")]
+-- >>> preferTransaction $ fromHeaders [("Prefer", "tx=commit, tx=rollback")]
 -- Just Commit
 --
 -- This is also the case across multiple headers:
 --
 -- >>> :{
--   preferResolution . fromHeaders True $
+--   preferResolution . fromHeaders $
 --     [ ("Prefer", "resolution=ignore-duplicates")
 --     , ("Prefer", "resolution=merge-duplicates")
 --     ]
@@ -93,30 +86,28 @@ data Preferences
 --
 -- Preferences not recognized by the application are ignored:
 --
-- >>> preferResolution $ fromHeaders True [("Prefer", "resolution=foo")]
+-- >>> preferResolution $ fromHeaders [("Prefer", "resolution=foo")]
 -- Nothing
 --
 -- Preferences can be separated by arbitrary amounts of space, lower-case header is also recognized:
 --
-- >>> pPrint $ fromHeaders True [("prefer", "count=exact,    tx=commit   ,return=representation , missing=default")]
+-- >>> pPrint $ fromHeaders [("prefer", "count=exact,    tx=commit   ,return=minimal")]
 -- Preferences
 --     { preferResolution = Nothing
--     , preferRepresentation = Just Full
+--     , preferRepresentation = Just None
 --     , preferParameters = Nothing
 --     , preferCount = Just ExactCount
 --     , preferTransaction = Just Commit
--     , preferMissing = Just ApplyDefaults
 --     }
 --
-fromHeaders :: Bool -> [HTTP.Header] -> Preferences
-fromHeaders allowTxEndOverride headers =
+fromHeaders :: [HTTP.Header] -> Preferences
+fromHeaders headers =
  Preferences
-    { preferResolution     = parsePrefs [MergeDuplicates, IgnoreDuplicates]
+    { preferResolution = parsePrefs [MergeDuplicates, IgnoreDuplicates]
    , preferRepresentation = parsePrefs [Full, None, HeadersOnly]
-    , preferParameters     = parsePrefs [SingleObject]
-    , preferCount          = parsePrefs [ExactCount, PlannedCount, EstimatedCount]
-    , preferTransaction    = if allowTxEndOverride then parsePrefs [Commit, Rollback] else Nothing
-    , preferMissing        = parsePrefs [ApplyDefaults, ApplyNulls]
+    , preferParameters = parsePrefs [SingleObject, MultipleObjects]
+    , preferCount = parsePrefs [ExactCount, PlannedCount, EstimatedCount]
+    , preferTransaction = parsePrefs [Commit, Rollback]
    }
  where
    prefHeaders = filter ((==) HTTP.hPrefer . fst) headers
@@ -129,22 +120,6 @@ fromHeaders allowTxEndOverride headers =
    prefMap :: ToHeaderValue a => [a] -> Map.Map ByteString a
    prefMap = Map.fromList . fmap (\pref -> (toHeaderValue pref, pref))

-prefAppliedHeader :: Preferences -> Maybe HTTP.Header
-prefAppliedHeader Preferences {preferResolution, preferRepresentation, preferParameters, preferCount, preferTransaction, preferMissing } =
-  if null prefsVals
-    then Nothing
-    else Just (HTTP.hPreferenceApplied, combined)
-  where
-    combined = BS.intercalate ", " prefsVals
-    prefsVals = catMaybes [
-        toHeaderValue <$> preferResolution
-      , toHeaderValue <$> preferMissing
-      , toHeaderValue <$> preferRepresentation
-      , toHeaderValue <$> preferParameters
-      , toHeaderValue <$> preferCount
-      , toHeaderValue <$> preferTransaction
-      ]
-
 -- |
 -- Convert a preference into the value that we look for in the 'Prefer' headers.
 --
@@ -154,6 +129,16 @@ prefAppliedHeader Preferences {preferResolution, preferRepresentation, preferPar
 class ToHeaderValue a where
  toHeaderValue :: a -> ByteString

+-- |
+-- Header to indicate that a preference has been applied.
+--
+-- >>> toAppliedHeader MergeDuplicates
+-- ("Preference-Applied","resolution=merge-duplicates")
+--
+class ToHeaderValue a => ToAppliedHeader a where
+  toAppliedHeader :: a -> HTTP.Header
+  toAppliedHeader x = (HTTP.hPreferenceApplied, toHeaderValue x)
+
 -- | How to handle duplicate values.
 data PreferResolution
  = MergeDuplicates
@@ -163,12 +148,14 @@ instance ToHeaderValue PreferResolution where
  toHeaderValue MergeDuplicates  = "resolution=merge-duplicates"
  toHeaderValue IgnoreDuplicates = "resolution=ignore-duplicates"

+instance ToAppliedHeader PreferResolution
+
 -- |
 -- How to return the mutated data.
 --
 -- From https://tools.ietf.org/html/rfc7240#section-4.2
 data PreferRepresentation
-  = Full        -- ^ Return the body.
+  = Full        -- ^ Return the body plus the Location header(in case of POST).
  | HeadersOnly -- ^ Return the Location header(in case of POST). This needs a SELECT privilege on the pk.
  | None        -- ^ Return nothing from the mutated data.
  deriving Eq
@@ -181,10 +168,12 @@ instance ToHeaderValue PreferRepresentation where
 -- | How to pass parameters to stored procedures.
 data PreferParameters
  = SingleObject    -- ^ Pass all parameters as a single json object to a stored procedure.
+  | MultipleObjects -- ^ Pass an array of json objects as params to a stored procedure.
  deriving Eq

 instance ToHeaderValue PreferParameters where
  toHeaderValue SingleObject    = "params=single-object"
+  toHeaderValue MultipleObjects = "params=multiple-objects"

 -- | How to determine the count of (expected) results
 data PreferCount
@@ -198,10 +187,6 @@ instance ToHeaderValue PreferCount where
  toHeaderValue PlannedCount   = "count=planned"
  toHeaderValue EstimatedCount = "count=estimated"

-shouldCount :: Maybe PreferCount -> Bool
-shouldCount prefCount =
-  prefCount == Just ExactCount || prefCount == Just EstimatedCount
-
 -- | Whether to commit or roll back transactions.
 data PreferTransaction
  = Commit   -- ^ Commit transaction - the default.
@@ -212,14 +197,4 @@ instance ToHeaderValue PreferTransaction where
  toHeaderValue Commit   = "tx=commit"
  toHeaderValue Rollback = "tx=rollback"

-- |
-- How to handle the insertion/update when the keys specified in ?columns are not present
-- in the json body.
-data PreferMissing
-  = ApplyDefaults  -- ^ Use the default column value for missing values.
-  | ApplyNulls     -- ^ Use the null value for missing values.
-  deriving Eq
-
-instance ToHeaderValue PreferMissing where
-  toHeaderValue ApplyDefaults = "missing=default"
-  toHeaderValue ApplyNulls    = "missing=null"
+instance ToAppliedHeader PreferTransaction
@@ -0,0 +1,232 @@
+{-# LANGUAGE DuplicateRecordFields #-}
+module PostgREST.Request.Types
+  ( Alias
+  , Depth
+  , EmbedParam(..)
+  , EmbedPath
+  , Field
+  , Filter(..)
+  , Hint
+  , CallQuery(..)
+  , CallParams(..)
+  , CallRequest
+  , JoinCondition(..)
+  , JoinType(..)
+  , JsonOperand(..)
+  , JsonOperation(..)
+  , JsonPath
+  , ListVal
+  , LogicOperator(..)
+  , LogicTree(..)
+  , MutateQuery(..)
+  , MutateRequest
+  , NodeName
+  , OpExpr(..)
+  , Operation (..)
+  , OrderDirection(..)
+  , OrderNulls(..)
+  , OrderTerm(..)
+  , ReadNode
+  , ReadQuery(..)
+  , ReadRequest
+  , SelectItem
+  , SingleVal
+  , TrileanVal(..)
+  , fstFieldNames
+  ) where
+
+import qualified Data.ByteString.Lazy as LBS
+import qualified Data.Set             as S
+
+import Data.Tree (Tree (..))
+
+import PostgREST.DbStructure.Identifiers  (FieldName,
+                                           QualifiedIdentifier)
+import PostgREST.DbStructure.Proc         (ProcParam (..))
+import PostgREST.DbStructure.Relationship (Relationship)
+import PostgREST.RangeQuery               (NonnegRange)
+import PostgREST.Request.Preferences      (PreferResolution)
+
+import Protolude
+
+
+type ReadRequest = Tree ReadNode
+type MutateRequest = MutateQuery
+type CallRequest = CallQuery
+
+type ReadNode =
+  (ReadQuery, (NodeName, Maybe Relationship, Maybe Alias, Maybe Hint, Maybe JoinType, Depth))
+
+type NodeName = Text
+type Depth = Integer
+
+data ReadQuery = Select
+  { select         :: [SelectItem]
+  , from           :: QualifiedIdentifier
+  -- ^ A table alias is used in case of self joins
+  , fromAlias      :: Maybe Alias
+  -- ^ Only used for Many to Many joins. Parent and Child joins use explicit joins.
+  , implicitJoins  :: [QualifiedIdentifier]
+  , where_         :: [LogicTree]
+  , joinConditions :: [JoinCondition]
+  , order          :: [OrderTerm]
+  , range_         :: NonnegRange
+  }
+  deriving (Eq)
+
+data JoinCondition =
+  JoinCondition
+    (QualifiedIdentifier, FieldName)
+    (QualifiedIdentifier, FieldName)
+  deriving (Eq)
+
+data OrderTerm = OrderTerm
+  { otTerm      :: Field
+  , otDirection :: Maybe OrderDirection
+  , otNullOrder :: Maybe OrderNulls
+  }
+  deriving (Eq)
+
+data OrderDirection
+  = OrderAsc
+  | OrderDesc
+  deriving (Eq)
+
+data OrderNulls
+  = OrderNullsFirst
+  | OrderNullsLast
+  deriving (Eq)
+
+data MutateQuery
+  = Insert
+      { in_        :: QualifiedIdentifier
+      , insCols    :: S.Set FieldName
+      , insBody    :: Maybe LBS.ByteString
+      , onConflict :: Maybe (PreferResolution, [FieldName])
+      , where_     :: [LogicTree]
+      , returning  :: [FieldName]
+      }
+  | Update
+      { in_       :: QualifiedIdentifier
+      , updCols   :: S.Set FieldName
+      , updBody   :: Maybe LBS.ByteString
+      , where_    :: [LogicTree]
+      , returning :: [FieldName]
+      }
+  | Delete
+      { in_       :: QualifiedIdentifier
+      , where_    :: [LogicTree]
+      , returning :: [FieldName]
+      }
+
+data CallQuery = FunctionCall
+  { funCQi           :: QualifiedIdentifier
+  , funCParams       :: CallParams
+  , funCArgs         :: Maybe LBS.ByteString
+  , funCScalar       :: Bool
+  , funCMultipleCall :: Bool
+  , funCReturning    :: [FieldName]
+  }
+
+data CallParams
+  = KeyParams [ProcParam] -- ^ Call with key params: func(a := val1, b:= val2)
+  | OnePosParam ProcParam -- ^ Call with positional params(only one supported): func(val)
+
+-- | The select value in `/tbl?select=alias:field::cast`
+type SelectItem = (Field, Maybe Cast, Maybe Alias, Maybe Hint, Maybe JoinType)
+
+type Field = (FieldName, JsonPath)
+type Cast = Text
+type Alias = Text
+type Hint = Text
+
+data EmbedParam
+  -- | Disambiguates an embedding operation when there's multiple relationships
+  -- between two tables. Can be the name of a foreign key constraint, column
+  -- name or the junction in an m2m relationship.
+  = EPHint Hint
+  | EPJoinType JoinType
+
+data JoinType
+  = JTInner
+  | JTLeft
+  deriving Eq
+
+-- | Path of the embedded levels, e.g "clients.projects.name=eq.." gives Path
+-- ["clients", "projects"]
+type EmbedPath = [Text]
+
+-- | Json path operations as specified in
+-- https://www.postgresql.org/docs/current/static/functions-json.html
+type JsonPath = [JsonOperation]
+
+-- | Represents the single arrow `->` or double arrow `->>` operators
+data JsonOperation
+  = JArrow { jOp :: JsonOperand }
+  | J2Arrow { jOp :: JsonOperand }
+  deriving (Eq)
+
+-- | Represents the key(`->'key'`) or index(`->'1`::int`), the index is Text
+-- because we reuse our escaping functons and let pg do the casting with
+-- '1'::int
+data JsonOperand
+  = JKey { jVal :: Text }
+  | JIdx { jVal :: Text }
+  deriving (Eq)
+
+-- First level FieldNames(e.g get a,b from /table?select=a,b,other(c,d))
+fstFieldNames :: ReadRequest -> [FieldName]
+fstFieldNames (Node (sel, _) _) =
+  fst . (\(f, _, _, _, _) -> f) <$> select sel
+
+
+-- | Boolean logic expression tree e.g. "and(name.eq.N,or(id.eq.1,id.eq.2))" is:
+--
+--            And
+--           /   \
+--  name.eq.N     Or
+--               /  \
+--         id.eq.1   id.eq.2
+data LogicTree
+  = Expr Bool LogicOperator [LogicTree]
+  | Stmnt Filter
+  deriving (Eq)
+
+data LogicOperator
+  = And
+  | Or
+  deriving Eq
+
+data Filter = Filter
+  { field  :: Field
+  , opExpr :: OpExpr
+  }
+  deriving (Eq)
+
+data OpExpr =
+  OpExpr Bool Operation
+  deriving (Eq)
+
+data Operation
+  = Op Operator SingleVal
+  | In ListVal
+  | Is TrileanVal
+  | Fts Operator (Maybe Language) SingleVal
+  deriving (Eq)
+
+type Operator = Text
+type Language = Text
+
+-- | Represents a single value in a filter, e.g. id=eq.singleval
+type SingleVal = Text
+
+-- | Represents a list value in a filter, e.g. id=in.(val1,val2,val3)
+type ListVal = [Text]
+
+-- | Three-valued logic values
+data TrileanVal
+  = TriTrue
+  | TriFalse
+  | TriNull
+  | TriUnknown
+  deriving Eq
@@ -1,291 +0,0 @@
-{- |
-   Module      : PostgREST.Response
-   Description : Generate HTTP Response
-}
-{-# LANGUAGE NamedFieldPuns  #-}
-{-# LANGUAGE RecordWildCards #-}
-module PostgREST.Response
-  ( createResponse
-  , deleteResponse
-  , infoIdentResponse
-  , infoProcResponse
-  , infoRootResponse
-  , invokeResponse
-  , openApiResponse
-  , readResponse
-  , singleUpsertResponse
-  , updateResponse
-  , addRetryHint
-  , isServiceUnavailable
-  , traceHeaderMiddleware
-  ) where
-
-import qualified Data.Aeson                as JSON
-import qualified Data.ByteString.Char8     as BS
-import qualified Data.ByteString.Lazy      as LBS
-import qualified Data.HashMap.Strict       as HM
-import qualified Data.List                 as L
-import           Data.Text.Read            (decimal)
-import qualified Network.HTTP.Types.Header as HTTP
-import qualified Network.HTTP.Types.Status as HTTP
-import qualified Network.HTTP.Types.URI    as HTTP
-import qualified Network.Wai               as Wai
-
-import qualified PostgREST.Error            as Error
-import qualified PostgREST.MediaType        as MediaType
-import qualified PostgREST.RangeQuery       as RangeQuery
-import qualified PostgREST.Response.OpenAPI as OpenAPI
-
-import PostgREST.ApiRequest              (ApiRequest (..),
-                                          InvokeMethod (..))
-import PostgREST.ApiRequest.Preferences  (PreferRepresentation (..),
-                                          Preferences (..),
-                                          prefAppliedHeader,
-                                          shouldCount)
-import PostgREST.ApiRequest.QueryParams  (QueryParams (..))
-import PostgREST.Config                  (AppConfig (..))
-import PostgREST.MediaType               (MediaType (..))
-import PostgREST.Plan                    (MutateReadPlan (..))
-import PostgREST.Plan.MutatePlan         (MutatePlan (..))
-import PostgREST.Query.Statements        (ResultSet (..))
-import PostgREST.Response.GucHeader      (GucHeader, unwrapGucHeader)
-import PostgREST.SchemaCache             (SchemaCache (..))
-import PostgREST.SchemaCache.Identifiers (QualifiedIdentifier (..),
-                                          Schema)
-import PostgREST.SchemaCache.Routine     (FuncVolatility (..),
-                                          Routine (..), RoutineMap)
-import PostgREST.SchemaCache.Table       (Table (..), TablesMap)
-
-import qualified PostgREST.ApiRequest.Types    as ApiRequestTypes
-import qualified PostgREST.SchemaCache.Routine as Routine
-
-import Protolude      hiding (Handler, toS)
-import Protolude.Conv (toS)
-
-
-readResponse :: Bool -> QualifiedIdentifier -> ApiRequest -> ResultSet -> Wai.Response
-readResponse headersOnly identifier ctxApiRequest@ApiRequest{iPreferences=Preferences{..},..} resultSet = case resultSet of
-  RSStandard{..} -> do
-    let
-      (status, contentRange) = RangeQuery.rangeStatusHeader iTopLevelRange rsQueryTotal rsTableTotal
-      response = gucResponse rsGucStatus rsGucHeaders
-      prefHeader = maybeToList . prefAppliedHeader $ Preferences Nothing Nothing Nothing preferCount preferTransaction Nothing
-      headers =
-        [ contentRange
-        , ( "Content-Location"
-          , "/"
-              <> toUtf8 (qiName identifier)
-              <> if BS.null (qsCanonical iQueryParams) then mempty else "?" <> qsCanonical iQueryParams
-          )
-        ]
-        ++ contentTypeHeaders ctxApiRequest
-        ++ prefHeader
-      rsOrErrBody = if status == HTTP.status416
-        then Error.errorPayload $ Error.ApiRequestError $ ApiRequestTypes.InvalidRange
-          $ ApiRequestTypes.OutOfBounds (show $ RangeQuery.rangeOffset iTopLevelRange) (maybe "0" show rsTableTotal)
-        else LBS.fromStrict rsBody
-
-    response status headers $ if headersOnly then mempty else rsOrErrBody
-
-  RSPlan plan ->
-    Wai.responseLBS HTTP.status200 (contentTypeHeaders ctxApiRequest) $ LBS.fromStrict plan
-
-createResponse :: QualifiedIdentifier -> MutateReadPlan -> ApiRequest -> ResultSet -> Wai.Response
-createResponse QualifiedIdentifier{..} MutateReadPlan{mrMutatePlan} ctxApiRequest@ApiRequest{iPreferences=Preferences{..}, ..} resultSet = case resultSet of
-  RSStandard{..} -> do
-    let
-      pkCols = case mrMutatePlan of { Insert{insPkCols} -> insPkCols; _ -> mempty;}
-      response = gucResponse rsGucStatus rsGucHeaders
-      prefHeader = prefAppliedHeader $
-        Preferences (if null pkCols && isNothing (qsOnConflict iQueryParams) then Nothing else preferResolution)
-        preferRepresentation Nothing preferCount preferTransaction preferMissing
-      headers =
-        catMaybes
-          [ if null rsLocation then
-              Nothing
-            else
-              Just
-                ( HTTP.hLocation
-                , "/"
-                    <> toUtf8 qiName
-                    <> HTTP.renderSimpleQuery True rsLocation
-                )
-          , Just . RangeQuery.contentRangeH 1 0 $
-              if shouldCount preferCount then Just rsQueryTotal else Nothing
-          , prefHeader
-          ]
-
-    case preferRepresentation of
-      Just Full -> response HTTP.status201 (headers ++ contentTypeHeaders ctxApiRequest) (LBS.fromStrict rsBody)
-      Just None -> response HTTP.status201 headers mempty
-      Just HeadersOnly -> response HTTP.status201 headers mempty
-      Nothing -> response HTTP.status201 headers mempty
-
-  RSPlan plan ->
-    Wai.responseLBS HTTP.status200 (contentTypeHeaders ctxApiRequest) $ LBS.fromStrict plan
-
-
-updateResponse :: ApiRequest -> ResultSet -> Wai.Response
-updateResponse ctxApiRequest@ApiRequest{iPreferences=Preferences{..}} resultSet = case resultSet of
-  RSStandard{..} -> do
-    let
-      response = gucResponse rsGucStatus rsGucHeaders
-      contentRangeHeader =
-        Just . RangeQuery.contentRangeH 0 (rsQueryTotal - 1) $
-          if shouldCount preferCount then Just rsQueryTotal else Nothing
-      prefHeader = prefAppliedHeader $ Preferences Nothing preferRepresentation Nothing preferCount preferTransaction preferMissing
-      headers = catMaybes [contentRangeHeader, prefHeader]
-
-    case preferRepresentation of
-        Just Full -> response HTTP.status200 (headers ++ contentTypeHeaders ctxApiRequest) (LBS.fromStrict rsBody)
-        Just None -> response HTTP.status204 headers mempty
-        _ -> response HTTP.status204 headers mempty
-
-  RSPlan plan ->
-    Wai.responseLBS HTTP.status200 (contentTypeHeaders ctxApiRequest) $ LBS.fromStrict plan
-
-singleUpsertResponse :: ApiRequest -> ResultSet -> Wai.Response
-singleUpsertResponse ctxApiRequest@ApiRequest{iPreferences=Preferences{..}} resultSet = case resultSet of
-  RSStandard {..} -> do
-    let
-      response = gucResponse rsGucStatus rsGucHeaders
-      prefHeader = maybeToList . prefAppliedHeader $ Preferences Nothing preferRepresentation Nothing preferCount preferTransaction Nothing
-
-    case preferRepresentation of
-      Just Full -> response HTTP.status200 (contentTypeHeaders ctxApiRequest ++ prefHeader) (LBS.fromStrict rsBody)
-      Just None -> response HTTP.status204 prefHeader mempty
-      _ -> response HTTP.status204 prefHeader mempty
-
-  RSPlan plan ->
-    Wai.responseLBS HTTP.status200 (contentTypeHeaders ctxApiRequest) $ LBS.fromStrict plan
-
-deleteResponse :: ApiRequest -> ResultSet -> Wai.Response
-deleteResponse ctxApiRequest@ApiRequest{iPreferences=Preferences{..}} resultSet = case resultSet of
-  RSStandard {..} -> do
-    let
-      response = gucResponse rsGucStatus rsGucHeaders
-      contentRangeHeader =
-        RangeQuery.contentRangeH 1 0 $
-          if shouldCount preferCount then Just rsQueryTotal else Nothing
-      prefHeader = maybeToList . prefAppliedHeader $ Preferences Nothing preferRepresentation Nothing preferCount preferTransaction Nothing
-      headers = contentRangeHeader : prefHeader
-
-    case preferRepresentation of
-        Just Full -> response HTTP.status200 (headers ++ contentTypeHeaders ctxApiRequest) (LBS.fromStrict rsBody)
-        Just None -> response HTTP.status204 headers mempty
-        _ -> response HTTP.status204 headers mempty
-
-  RSPlan plan ->
-    Wai.responseLBS HTTP.status200 (contentTypeHeaders ctxApiRequest) $ LBS.fromStrict plan
-
-infoIdentResponse :: QualifiedIdentifier -> SchemaCache -> Wai.Response
-infoIdentResponse identifier sCache =
-  case HM.lookup identifier (dbTables sCache) of
-    Just tbl -> respondInfo $ allowH tbl
-    Nothing  -> Error.errorResponseFor $ Error.ApiRequestError ApiRequestTypes.NotFound
-  where
-    allowH table =
-      let hasPK = not . null $ tablePKCols table in
-      BS.intercalate "," $
-          ["OPTIONS,GET,HEAD"] ++
-          ["POST" | tableInsertable table] ++
-          ["PUT" | tableInsertable table && tableUpdatable table && hasPK] ++
-          ["PATCH" | tableUpdatable table] ++
-          ["DELETE" | tableDeletable table]
-
-infoProcResponse :: Routine -> Wai.Response
-infoProcResponse proc | pdVolatility proc == Volatile = respondInfo "OPTIONS,POST"
-                      | otherwise                     = respondInfo "OPTIONS,GET,HEAD,POST"
-
-infoRootResponse :: Wai.Response
-infoRootResponse = respondInfo "OPTIONS,GET,HEAD"
-
-respondInfo :: ByteString -> Wai.Response
-respondInfo allowHeader =
-  let allOrigins = ("Access-Control-Allow-Origin", "*") in
-  Wai.responseLBS HTTP.status200 [allOrigins, (HTTP.hAllow, allowHeader)] mempty
-
-invokeResponse :: InvokeMethod -> Routine -> ApiRequest -> ResultSet -> Wai.Response
-invokeResponse invMethod proc ctxApiRequest@ApiRequest{iPreferences=Preferences{..}, ..} resultSet = case resultSet of
-  RSStandard {..} -> do
-    let
-      response = gucResponse rsGucStatus rsGucHeaders
-      (status, contentRange) =
-        RangeQuery.rangeStatusHeader iTopLevelRange rsQueryTotal rsTableTotal
-      rsOrErrBody = if status == HTTP.status416
-        then Error.errorPayload $ Error.ApiRequestError $ ApiRequestTypes.InvalidRange
-          $ ApiRequestTypes.OutOfBounds (show $ RangeQuery.rangeOffset iTopLevelRange) (maybe "0" show rsTableTotal)
-        else LBS.fromStrict rsBody
-      prefHeader = maybeToList . prefAppliedHeader $ Preferences Nothing Nothing preferParameters preferCount preferTransaction Nothing
-      headers = contentRange : prefHeader
-
-    if Routine.funcReturnsVoid proc then
-        response HTTP.status204 headers mempty
-      else
-        response status
-          (headers ++ contentTypeHeaders ctxApiRequest)
-          (if invMethod == InvHead then mempty else rsOrErrBody)
-
-  RSPlan plan ->
-    Wai.responseLBS HTTP.status200 (contentTypeHeaders ctxApiRequest) $ LBS.fromStrict plan
-
-openApiResponse :: (Text, Text) -> Bool -> Maybe (TablesMap, RoutineMap, Maybe Text) -> AppConfig -> SchemaCache -> Schema -> Bool -> Wai.Response
-openApiResponse versions headersOnly body conf sCache schema negotiatedByProfile =
-  Wai.responseLBS HTTP.status200
-    (MediaType.toContentType MTOpenAPI : maybeToList (profileHeader schema negotiatedByProfile))
-    (maybe mempty (\(x, y, z) -> if headersOnly then mempty else OpenAPI.encode versions conf sCache x y z) body)
-
-- | Response with headers and status overridden from GUCs.
-gucResponse
-  :: Maybe Text
-  -> Maybe BS.ByteString
-  -> HTTP.Status
-  -> [HTTP.Header]
-  -> LBS.ByteString
-  -> Wai.Response
-gucResponse rsGucStatus rsGucHeaders status headers body =
-  case (,) <$> decodeGucStatus rsGucStatus <*> decodeGucHeaders rsGucHeaders of
-    Left err -> Error.errorResponseFor err
-    Right (gucStatus, gucHeaders) ->
-      Wai.responseLBS (fromMaybe status gucStatus) (addHeadersIfNotIncluded headers (map unwrapGucHeader gucHeaders)) body
-
-decodeGucHeaders :: Maybe BS.ByteString -> Either Error.Error [GucHeader]
-decodeGucHeaders =
-  maybe (Right []) $ first (const Error.GucHeadersError) . JSON.eitherDecode . LBS.fromStrict
-
-decodeGucStatus :: Maybe Text -> Either Error.Error (Maybe HTTP.Status)
-decodeGucStatus =
-  maybe (Right Nothing) $ first (const Error.GucStatusError) . fmap (Just . toEnum . fst) . decimal
-
-contentTypeHeaders :: ApiRequest -> [HTTP.Header]
-contentTypeHeaders ApiRequest{..} =
-  MediaType.toContentType iAcceptMediaType : maybeToList (profileHeader iSchema iNegotiatedByProfile)
-
-profileHeader :: Schema -> Bool -> Maybe HTTP.Header
-profileHeader schema negotiatedByProfile =
-  if negotiatedByProfile
-    then Just $ (,) "Content-Profile" (toS schema)
-  else
-    Nothing
-
-addRetryHint :: Int -> Wai.Response -> Wai.Response
-addRetryHint delay response = do
-  let h = ("Retry-After", BS.pack $ show delay)
-  Wai.mapResponseHeaders (\hs -> if isServiceUnavailable response then h:hs else hs) response
-
-isServiceUnavailable :: Wai.Response -> Bool
-isServiceUnavailable response = Wai.responseStatus response == HTTP.status503
-
-- | Add headers not already included to allow the user to override them instead of duplicating them
-addHeadersIfNotIncluded :: [HTTP.Header] -> [HTTP.Header] -> [HTTP.Header]
-addHeadersIfNotIncluded newHeaders initialHeaders =
-  filter (\(nk, _) -> isNothing $ find (\(ik, _) -> ik == nk) initialHeaders) newHeaders ++
-  initialHeaders
-
-traceHeaderMiddleware :: AppConfig -> Wai.Middleware
-traceHeaderMiddleware AppConfig{configServerTraceHeader} app req respond =
-  case configServerTraceHeader of
-    Nothing -> app req respond
-    Just hdr ->
-      let hdrVal = L.lookup hdr $ Wai.requestHeaders req in
-      app req (respond . Wai.mapResponseHeaders ([(hdr, fromMaybe mempty hdrVal)] ++))
@@ -1,73 +0,0 @@
-{-# LANGUAGE DeriveAnyClass #-}
-{-# LANGUAGE DeriveGeneric  #-}
-
-module PostgREST.SchemaCache.Relationship
-  ( Cardinality(..)
-  , Relationship(..)
-  , Junction(..)
-  , RelationshipsMap
-  , relIsToOne
-  ) where
-
-import qualified Data.Aeson          as JSON
-import qualified Data.HashMap.Strict as HM
-
-import PostgREST.SchemaCache.Identifiers (FieldName,
-                                          QualifiedIdentifier, Schema)
-
-import Protolude
-
-
-- | Relationship between two tables.
-data Relationship = Relationship
-  { relTable        :: QualifiedIdentifier
-  , relForeignTable :: QualifiedIdentifier
-  , relIsSelf       :: Bool -- ^ Whether is a self relationship
-  , relCardinality  :: Cardinality
-  , relTableIsView  :: Bool
-  , relFTableIsView :: Bool
-  }
-  | ComputedRelationship
-  { relFunction     :: QualifiedIdentifier
-  , relTable        :: QualifiedIdentifier
-  , relForeignTable :: QualifiedIdentifier
-  , relTableAlias   :: QualifiedIdentifier
-  , relToOne        :: Bool
-  , relIsSelf       :: Bool
-  }
-  deriving (Eq, Show, Ord, Generic, JSON.ToJSON)
-
-- | The relationship cardinality
-- | https://en.wikipedia.org/wiki/Cardinality_(data_modeling)
-data Cardinality
-  = O2M {relCons :: FKConstraint, relColumns :: [(FieldName, FieldName)]}
-  -- ^ one-to-many
-  | M2O {relCons :: FKConstraint, relColumns :: [(FieldName, FieldName)]}
-  -- ^ many-to-one
-  | O2O {relCons :: FKConstraint, relColumns :: [(FieldName, FieldName)]}
-  -- ^ one-to-one, this is a refinement over M2O so operating on it is pretty much the same as M2O
-  | M2M Junction
-  -- ^ many-to-many
-  deriving (Eq, Show, Ord, Generic, JSON.ToJSON)
-
-type FKConstraint = Text
-
-- | Junction table on an M2M relationship
-data Junction = Junction
-  { junTable       :: QualifiedIdentifier
-  , junConstraint1 :: FKConstraint
-  , junConstraint2 :: FKConstraint
-  , junColsSource  :: [(FieldName, FieldName)]
-  , junColsTarget  :: [(FieldName, FieldName)]
-  }
-  deriving (Eq, Show, Ord, Generic, JSON.ToJSON)
-
-- | Key based on the source table and the foreign table schema
-type RelationshipsMap = HM.HashMap (QualifiedIdentifier, Schema)  [Relationship]
-
-relIsToOne :: Relationship -> Bool
-relIsToOne rel = case rel of
-  Relationship{relCardinality=M2O _ _} -> True
-  Relationship{relCardinality=O2O _ _} -> True
-  ComputedRelationship{relToOne=True}  -> True
-  _                                    -> False
@@ -1,29 +0,0 @@
-{-# LANGUAGE DeriveAnyClass #-}
-{-# LANGUAGE DeriveGeneric  #-}
-
-module PostgREST.SchemaCache.Representations
-  ( DataRepresentation(..)
-  , RepresentationsMap
-  ) where
-
-import qualified Data.Aeson          as JSON
-import qualified Data.HashMap.Strict as HM
-
-
-import Protolude
-
-- | Data representations allow user customisation of how to present and receive data through APIs, per field.
-- This structure is used for the library of available transforms. It answers questions like:
-- - What function, if any, should be used to present a certain field that's been selected for API output?
-- - How do we parse incoming data for a certain field type when inserting or updating?
-- - And similarly, how do we parse textual data in a query string to be used as a filter?
--
-- Support for outputting special formats like CSV and binary data would fit into the same system.
-data DataRepresentation = DataRepresentation
-  { drSourceType :: Text
-  , drTargetType :: Text
-  , drFunction   :: Text
-  } deriving (Eq, Show, Generic, JSON.ToJSON, JSON.FromJSON)
-
-- The representation map maps from (source type, target type) to a DR.
-type RepresentationsMap = HM.HashMap (Text, Text) DataRepresentation
@@ -1,132 +0,0 @@
-{-# LANGUAGE DeriveAnyClass #-}
-{-# LANGUAGE DeriveGeneric  #-}
-
-module PostgREST.SchemaCache.Routine
-  ( PgType(..)
-  , Routine(..)
-  , RoutineParam(..)
-  , FuncVolatility(..)
-  , RoutineMap
-  , RetType(..)
-  , funcReturnsScalar
-  , funcReturnsSetOfScalar
-  , funcReturnsSingleComposite
-  , funcReturnsVoid
-  , funcTableName
-  , funcReturnsCompositeAlias
-  , ResultAggregate(..)
-  ) where
-
-import           Data.Aeson                 ((.=))
-import qualified Data.Aeson                 as JSON
-import qualified Data.HashMap.Strict        as HM
-import qualified Hasql.Transaction.Sessions as SQL
-
-import PostgREST.SchemaCache.Identifiers (FieldName,
-                                          QualifiedIdentifier (..),
-                                          Schema, TableName)
-
-import Protolude
-
-data PgType
-  = Scalar QualifiedIdentifier
-  | Composite QualifiedIdentifier Bool -- True if the composite is a domain alias(used to work around a bug in pg 11 and 12, see QueryBuilder.hs)
-  deriving (Eq, Show, Ord, Generic, JSON.ToJSON)
-
-data RetType
-  = Single PgType
-  | SetOf PgType
-  deriving (Eq, Show, Ord, Generic, JSON.ToJSON)
-
-data FuncVolatility
-  = Volatile
-  | Stable
-  | Immutable
-  deriving (Eq, Show, Ord, Generic, JSON.ToJSON)
-
-data Routine = Function
-  { pdSchema      :: Schema
-  , pdName        :: Text
-  , pdDescription :: Maybe Text
-  , pdParams      :: [RoutineParam]
-  , pdReturnType  :: RetType
-  , pdVolatility  :: FuncVolatility
-  , pdHasVariadic :: Bool
-  , pdIsoLvl      :: Maybe SQL.IsolationLevel
-  }
-  deriving (Eq, Show, Generic)
-- need to define JSON manually bc SQL.IsolationLevel doesn't have a JSON instance(and we can't define one for that type without getting a compiler error)
-instance JSON.ToJSON Routine where
-  toJSON (Function sch nam desc params ret vol hasVar _) = JSON.object
-    [
-      "pdSchema"      .= sch
-    , "pdName"        .= nam
-    , "pdDescription" .= desc
-    , "pdParams"      .= JSON.toJSON params
-    , "pdReturnType"  .= JSON.toJSON ret
-    , "pdVolatility"  .= JSON.toJSON vol
-    , "pdHasVariadic" .= JSON.toJSON hasVar
-    ]
-
-data RoutineParam = RoutineParam
-  { ppName          :: Text
-  , ppType          :: Text
-  , ppTypeMaxLength :: Text
-  , ppReq           :: Bool
-  , ppVar           :: Bool
-  }
-  deriving (Eq, Show, Ord, Generic, JSON.ToJSON)
-
-- Order by least number of params in the case of overloaded functions
-instance Ord Routine where
-  Function schema1 name1 des1 prms1 rt1 vol1 hasVar1 iso1 `compare` Function schema2 name2 des2 prms2 rt2 vol2 hasVar2 iso2
-    | schema1 == schema2 && name1 == name2 && length prms1 < length prms2  = LT
-    | schema2 == schema2 && name1 == name2 && length prms1 > length prms2  = GT
-    | otherwise = (schema1, name1, des1, prms1, rt1, vol1, hasVar1, iso1) `compare` (schema2, name2, des2, prms2, rt2, vol2, hasVar2, iso2)
-
-- | A map of all procs, all of which can be overloaded(one entry will have more than one Routine).
-- | It uses a HashMap for a faster lookup.
-type RoutineMap = HM.HashMap QualifiedIdentifier [Routine]
-
-data ResultAggregate
-   = BuiltinAggJson
-   | BuiltinAggSingleJson Bool
-   | BuiltinAggArrayJsonStrip
-   | BuiltinAggGeoJson
-   | BuiltinAggCsv
-   | BuiltinAggXml    (Maybe FieldName)
-   | BuiltinAggBinary (Maybe FieldName)
-   | NoAgg
-   deriving (Eq, Show)
-
-funcReturnsScalar :: Routine -> Bool
-funcReturnsScalar proc = case proc of
-  Function{pdReturnType = Single (Scalar{})} -> True
-  _                                          -> False
-
-funcReturnsSetOfScalar :: Routine -> Bool
-funcReturnsSetOfScalar proc = case proc of
-  Function{pdReturnType = SetOf (Scalar{})} -> True
-  _                                         -> False
-
-funcReturnsCompositeAlias :: Routine -> Bool
-funcReturnsCompositeAlias proc = case proc of
-  Function{pdReturnType = Single (Composite _ True)} -> True
-  Function{pdReturnType = SetOf (Composite _ True)}  -> True
-  _                                                  -> False
-
-funcReturnsSingleComposite :: Routine -> Bool
-funcReturnsSingleComposite proc = case proc of
-  Function{pdReturnType = Single (Composite _ _)} -> True
-  _                                               -> False
-
-funcReturnsVoid :: Routine -> Bool
-funcReturnsVoid proc = case proc of
-  Function{pdReturnType = Single (Scalar (QualifiedIdentifier "pg_catalog" "void"))} -> True
-  _                                                                                  -> False
-
-funcTableName :: Routine -> Maybe TableName
-funcTableName proc = case pdReturnType proc of
-  SetOf  (Composite qi _) -> Just $ qiName qi
-  Single (Composite qi _) -> Just $ qiName qi
-  _                       -> Nothing
@@ -1,58 +0,0 @@
-{-# LANGUAGE DeriveAnyClass    #-}
-{-# LANGUAGE DeriveGeneric     #-}
-{-# LANGUAGE FlexibleInstances #-}
-
-module PostgREST.SchemaCache.Table
-  ( Column(..)
-  , Table(..)
-  , tableColumnsList
-  , TablesMap
-  , ColumnMap
-  ) where
-
-import qualified Data.Aeson                 as JSON
-import qualified Data.HashMap.Strict        as HM
-import qualified Data.HashMap.Strict.InsOrd as HMI
-
-import PostgREST.SchemaCache.Identifiers (FieldName,
-                                          QualifiedIdentifier (..),
-                                          Schema, TableName)
-
-import Protolude
-
-
-data Table = Table
-  { tableSchema      :: Schema
-  , tableName        :: TableName
-  , tableDescription :: Maybe Text
-     -- TODO Find a better way to separate tables and views
-   , tableIsView     :: Bool
-    -- The following fields identify what can be done on the table/view, they're not related to the privileges granted to it
-  , tableInsertable  :: Bool
-  , tableUpdatable   :: Bool
-  , tableDeletable   :: Bool
-  , tablePKCols      :: [FieldName]
-  , tableColumns     :: ColumnMap
-  }
-  deriving (Show, Generic, JSON.ToJSON)
-
-tableColumnsList :: Table -> [Column]
-tableColumnsList = HMI.elems . tableColumns
-
-instance Eq Table where
-  Table{tableSchema=s1,tableName=n1} == Table{tableSchema=s2,tableName=n2} = s1 == s2 && n1 == n2
-
-data Column = Column
-  { colName        :: FieldName
-  , colDescription :: Maybe Text
-  , colNullable    :: Bool
-  , colType        :: Text
-  , colNominalType :: Text
-  , colMaxLen      :: Maybe Int32
-  , colDefault     :: Maybe Text
-  , colEnum        :: [Text]
-  }
-  deriving (Eq, Show, Ord, Generic, JSON.ToJSON)
-
-type TablesMap = HM.HashMap QualifiedIdentifier Table
-type ColumnMap = HMI.InsOrdHashMap FieldName Column
@@ -14,6 +14,7 @@ import System.Posix.Files (setFileMode)
 import System.Posix.Types (FileMode)

 import qualified PostgREST.AppState as AppState
+import qualified PostgREST.Workers  as Workers

 import Protolude

@@ -42,16 +43,17 @@ runAppWithSocket settings app socketFileMode socketFilePath =
 -- | Set signal handlers, only for systems with signals
 installSignalHandlers :: AppState.AppState -> IO ()
 installSignalHandlers appState = do
-  let interrupt = throwTo (AppState.getMainThreadId appState) UserInterrupt
-  install Signals.sigINT interrupt
-  install Signals.sigTERM interrupt
+  -- Releases the connection pool whenever the program is terminated,
+  -- see https://github.com/PostgREST/postgrest/issues/268
+  install Signals.sigINT $ AppState.releasePool appState
+  install Signals.sigTERM $ AppState.releasePool appState

-  -- The SIGUSR1 signal updates the internal 'SchemaCache' by running
+  -- The SIGUSR1 signal updates the internal 'DbStructure' by running
  -- 'connectionWorker' exactly as before.
-  install Signals.sigUSR1 $ AppState.connectionWorker appState
+  install Signals.sigUSR1 $ Workers.connectionWorker appState

  -- Re-read the config on SIGUSR2
-  install Signals.sigUSR2 $ AppState.reReadConfig False appState
+  install Signals.sigUSR2 $ Workers.reReadConfig False appState
  where
    install signal handler =
      void $ Signals.installHandler signal (Signals.Catch handler) Nothing
@@ -0,0 +1,263 @@
+{-# LANGUAGE LambdaCase      #-}
+{-# LANGUAGE RecordWildCards #-}
+
+module PostgREST.Workers
+  ( connectionWorker
+  , reReadConfig
+  , listener
+  ) where
+
+import qualified Data.Aeson                 as JSON
+import qualified Data.ByteString            as BS
+import qualified Data.ByteString.Lazy       as LBS
+import qualified Data.Text.Encoding         as T
+import qualified Hasql.Notifications        as SQL
+import qualified Hasql.Pool                 as SQL
+import qualified Hasql.Transaction.Sessions as SQL
+
+import Control.Retry    (RetryStatus, capDelay, exponentialBackoff,
+                         retrying, rsPreviousDelay)
+import Hasql.Connection (acquire)
+
+import PostgREST.AppState         (AppState)
+import PostgREST.Config           (AppConfig (..), readAppConfig)
+import PostgREST.Config.Database  (queryDbSettings, queryPgVersion)
+import PostgREST.Config.PgVersion (PgVersion (..), minimumPgVersion)
+import PostgREST.DbStructure      (queryDbStructure)
+import PostgREST.Error            (PgError (PgError), checkIsFatal,
+                                   errorPayload)
+
+import qualified PostgREST.AppState as AppState
+
+import Protolude
+
+
+-- | Current database connection status data ConnectionStatus
+data ConnectionStatus
+  = NotConnected
+  | Connected PgVersion
+  | FatalConnectionError Text
+  deriving (Eq)
+
+-- | Schema cache status
+data SCacheStatus
+  = SCLoaded
+  | SCOnRetry
+  | SCFatalFail
+
+-- | The purpose of this worker is to obtain a healthy connection to pg and an
+-- up-to-date schema cache(DbStructure).  This method is meant to be called
+-- multiple times by the same thread, but does nothing if the previous
+-- invocation has not terminated. In all cases this method does not halt the
+-- calling thread, the work is preformed in a separate thread.
+--
+-- Background thread that does the following :
+--  1. Tries to connect to pg server and will keep trying until success.
+--  2. Checks if the pg version is supported and if it's not it kills the main
+--     program.
+--  3. Obtains the dbStructure. If this fails, it goes back to 1.
+connectionWorker :: AppState -> IO ()
+connectionWorker appState = do
+  isWorkerOn <- AppState.getIsWorkerOn appState
+  -- Prevents multiple workers to be running at the same time. Could happen on
+  -- too many SIGUSR1s.
+  unless isWorkerOn $ do
+    AppState.putIsWorkerOn appState True
+    void $ forkIO work
+  where
+    work = do
+      AppConfig{..} <- AppState.getConfig appState
+      AppState.logWithZTime appState "Attempting to connect to the database..."
+      connected <- connectionStatus appState
+      case connected of
+        FatalConnectionError reason ->
+          -- Fatal error when connecting
+          AppState.logWithZTime appState reason >> killThread (AppState.getMainThreadId appState)
+        NotConnected ->
+          -- Unreachable because connectionStatus will keep trying to connect
+          return ()
+        Connected actualPgVersion -> do
+          -- Procede with initialization
+          AppState.putPgVersion appState actualPgVersion
+          when configDbChannelEnabled $
+            AppState.signalListener appState
+          AppState.logWithZTime appState "Connection successful"
+          -- this could be fail because the connection drops, but the
+          -- loadSchemaCache will pick the error and retry again
+          when configDbConfig $ reReadConfig False appState
+          scStatus <- loadSchemaCache appState
+          case scStatus of
+            SCLoaded ->
+              -- do nothing and proceed if the load was successful
+              return ()
+            SCOnRetry ->
+              work
+            SCFatalFail ->
+              -- die if our schema cache query has an error
+              killThread $ AppState.getMainThreadId appState
+          AppState.putIsWorkerOn appState False
+
+-- | Check if a connection from the pool allows access to the PostgreSQL
+-- database.  If not, the pool connections are released and a new connection is
+-- tried.  Releasing the pool is key for rapid recovery. Otherwise, the pool
+-- timeout would have to be reached for new healthy connections to be acquired.
+-- Which might not happen if the server is busy with requests. No idle
+-- connection, no pool timeout.
+--
+-- The connection tries are capped, but if the connection times out no error is
+-- thrown, just 'False' is returned.
+connectionStatus :: AppState -> IO ConnectionStatus
+connectionStatus appState =
+  retrying retrySettings shouldRetry $
+    const $ SQL.release pool >> getConnectionStatus
+  where
+    pool = AppState.getPool appState
+    retrySettings = capDelay delayMicroseconds $ exponentialBackoff backoffMicroseconds
+    delayMicroseconds = 32000000 -- 32 seconds
+    backoffMicroseconds = 1000000 -- 1 second
+
+    getConnectionStatus :: IO ConnectionStatus
+    getConnectionStatus = do
+      pgVersion <- SQL.use pool queryPgVersion
+      case pgVersion of
+        Left e -> do
+          let err = PgError False e
+          AppState.logWithZTime appState . T.decodeUtf8 . LBS.toStrict $ errorPayload err
+          case checkIsFatal err of
+            Just reason ->
+              return $ FatalConnectionError reason
+            Nothing ->
+              return NotConnected
+        Right version ->
+          if version < minimumPgVersion then
+            return . FatalConnectionError $
+              "Cannot run in this PostgreSQL version, PostgREST needs at least "
+              <> pgvName minimumPgVersion
+          else
+            return . Connected  $ version
+
+    shouldRetry :: RetryStatus -> ConnectionStatus -> IO Bool
+    shouldRetry rs isConnSucc = do
+      let
+        delay = fromMaybe 0 (rsPreviousDelay rs) `div` backoffMicroseconds
+        itShould = NotConnected == isConnSucc
+      when itShould . AppState.logWithZTime appState $
+        "Attempting to reconnect to the database in "
+        <> (show delay::Text)
+        <> " seconds..."
+      when itShould $ AppState.putRetryNextIn appState delay
+      return itShould
+
+-- | Load the DbStructure by using a connection from the pool.
+loadSchemaCache :: AppState -> IO SCacheStatus
+loadSchemaCache appState = do
+  AppConfig{..} <- AppState.getConfig appState
+  result <-
+    let transaction = if configDbPreparedStatements then SQL.transaction else SQL.unpreparedTransaction in
+    SQL.use (AppState.getPool appState) . transaction SQL.ReadCommitted SQL.Read $
+      queryDbStructure (toList configDbSchemas) configDbExtraSearchPath configDbPreparedStatements
+  case result of
+    Left e -> do
+      let
+        err = PgError False e
+        putErr = AppState.logWithZTime appState . T.decodeUtf8 . LBS.toStrict $ errorPayload err
+      case checkIsFatal err of
+        Just hint -> do
+          AppState.logWithZTime appState "A fatal error ocurred when loading the schema cache"
+          putErr
+          AppState.logWithZTime appState hint
+          return SCFatalFail
+        Nothing -> do
+          AppState.logWithZTime appState "An error ocurred when loading the schema cache"
+          putErr
+          return SCOnRetry
+
+    Right dbStructure -> do
+      AppState.putDbStructure appState dbStructure
+      when (isJust configDbRootSpec) .
+        AppState.putJsonDbS appState . LBS.toStrict $ JSON.encode dbStructure
+      AppState.logWithZTime appState "Schema cache loaded"
+      return SCLoaded
+
+-- | Starts a dedicated pg connection to LISTEN for notifications.  When a
+-- NOTIFY <db-channel> - with an empty payload - is done, it refills the schema
+-- cache.  It uses the connectionWorker in case the LISTEN connection dies.
+listener :: AppState -> IO ()
+listener appState = do
+  AppConfig{..} <- AppState.getConfig appState
+  let dbChannel = toS configDbChannel
+
+  -- The listener has to wait for a signal from the connectionWorker.
+  -- This is because when the connection to the db is lost, the listener also
+  -- tries to recover the connection, but not with the same pace as the connectionWorker.
+  -- Not waiting makes stderr quickly fill with connection retries messages from the listener.
+  AppState.waitListener appState
+
+  -- forkFinally allows to detect if the thread dies
+  void . flip forkFinally (handleFinally dbChannel) $ do
+    dbOrError <- acquire $ toUtf8 configDbUri
+    case dbOrError of
+      Right db -> do
+        AppState.logWithZTime appState $ "Listening for notifications on the " <> dbChannel <> " channel"
+        SQL.listen db $ SQL.toPgIdentifier dbChannel
+        SQL.waitForNotifications handleNotification db
+      _ ->
+        die $ "Could not listen for notifications on the " <> dbChannel <> " channel"
+  where
+    handleFinally dbChannel _ = do
+      -- if the thread dies, we try to recover
+      AppState.logWithZTime appState $ "Retrying listening for notifications on the " <> dbChannel <> " channel.."
+      -- assume the pool connection was also lost, call the connection worker
+      connectionWorker appState
+      -- retry the listener
+      listener appState
+
+    handleNotification _ msg
+      | BS.null msg            = scLoader -- reload the schema cache
+      | msg == "reload schema" = scLoader -- reload the schema cache
+      | msg == "reload config" = reReadConfig False appState -- reload the config
+      | otherwise              = pure () -- Do nothing if anything else than an empty message is sent
+
+    scLoader =
+      -- It's not necessary to check the loadSchemaCache success
+      -- here. If the connection drops, the thread will die and
+      -- proceed to recover.
+      void $ loadSchemaCache appState
+
+-- | Re-reads the config plus config options from the db
+reReadConfig :: Bool -> AppState -> IO ()
+reReadConfig startingUp appState = do
+  AppConfig{..} <- AppState.getConfig appState
+  dbSettings <-
+    if configDbConfig then do
+      qDbSettings <- queryDbSettings (AppState.getPool appState) configDbPreparedStatements
+      case qDbSettings of
+        Left e -> do
+          let
+            err = PgError False e
+            putErr = AppState.logWithZTime appState . T.decodeUtf8 . LBS.toStrict $ errorPayload err
+          AppState.logWithZTime appState
+            "An error ocurred when trying to query database settings for the config parameters"
+          case checkIsFatal err of
+            Just hint -> do
+              putErr
+              AppState.logWithZTime appState hint
+              killThread (AppState.getMainThreadId appState)
+            Nothing -> do
+              AppState.logWithZTime appState $ show e
+          pure []
+        Right x -> pure x
+    else
+      pure mempty
+  readAppConfig dbSettings configFilePath (Just configDbUri) >>= \case
+    Left err   ->
+      if startingUp then
+        panic err -- die on invalid config if the program is starting up
+      else
+        AppState.logWithZTime appState $ "Failed re-loading config: " <> err
+    Right newConf -> do
+      AppState.putConfig appState newConf
+      if startingUp then
+        pass
+      else
+        AppState.logWithZTime appState "Config re-loaded"
@@ -1,4 +1,4 @@
-resolver: lts-20.6 # 2023-01-09, GHC 9.2.5
+resolver: lts-18.14 # 2021-10-24, GHC 8.10.7

 nix:
  packages:
@@ -10,7 +10,10 @@ nix:
  pure: false

 extra-deps:
-  - git: https://github.com/PostgREST/postgresql-libpq.git
-    commit: 890a0a16cf57dd401420fdc6c7d576fb696003bc
-  - hasql-notifications-0.2.0.6
-  - hasql-pool-0.10
+  - hasql-dynamic-statements-0.3.1@sha256:c3a2c89c4a8b3711368dbd33f0ccfe46a493faa7efc2c85d3e354c56a01dfc48,2673
+  - hasql-implicits-0.1.0.2@sha256:5d54e09cb779a209681b139fb3cc726bae75134557932156340cc0a56dd834a8,1361
+  - protolude-0.3.1@sha256:1cc9e5a5c26c33a43c52b554443dd9779fef13974eaa0beec7ca6d2551b400da,2647
+  - ptr-0.16.8.1@sha256:525219ec5f5da5c699725f7efcef91b00a7d44120fc019878b85c09440bf51d6,2686
+  - wai-extra-3.1.8@sha256:bf3dbe8f4c707b502b2a88262ed71c807220651597b76b56983f864af6197890,7280
+  - wai-logger-2.3.7@sha256:19a0dc5122e22d274776d80786fb9501956f5e75b8f82464bbdad5604d154d82,1671
+  - warp-3.3.19@sha256:c6a47029537d42844386170d732cdfe6d85b2f4279bbaefdd9b50caff6faeebb,10910
@@ -5,33 +5,57 @@

 packages:
 - completed:
-    commit: 890a0a16cf57dd401420fdc6c7d576fb696003bc
-    git: https://github.com/PostgREST/postgresql-libpq.git
-    name: postgresql-libpq
    pantry-tree:
-      sha256: 074668b9669b9c49f3c522c8af5c608799a1965e203c463b188b2632995beac2
-      size: 1414
-    version: 0.9.4.3
+      sha256: b1b9a6a26ec765e5fe29f9a670a5c9ec7067ea00dee8491f0819284ff0201b6f
+      size: 641
+    hackage: hasql-dynamic-statements-0.3.1@sha256:c3a2c89c4a8b3711368dbd33f0ccfe46a493faa7efc2c85d3e354c56a01dfc48,2673
  original:
-    commit: 890a0a16cf57dd401420fdc6c7d576fb696003bc
-    git: https://github.com/PostgREST/postgresql-libpq.git
+    hackage: hasql-dynamic-statements-0.3.1@sha256:c3a2c89c4a8b3711368dbd33f0ccfe46a493faa7efc2c85d3e354c56a01dfc48,2673
 - completed:
-    hackage: hasql-notifications-0.2.0.6@sha256:16d783f5cd1660fad924fd3769380889de5804e057f09b304dcdc3a3ff11eb3c,2028
    pantry-tree:
-      sha256: 2319743501bb3c0bef801014ce61308b8666cef86ae5a97a0a283c0c1ec12d4f
-      size: 452
+      sha256: 2f00d1467d0e226b966c2cd7bac433c8948e2f7bbdf8a44936029f66fc20b5f3
+      size: 310
+    hackage: hasql-implicits-0.1.0.2@sha256:5d54e09cb779a209681b139fb3cc726bae75134557932156340cc0a56dd834a8,1361
  original:
-    hackage: hasql-notifications-0.2.0.6
+    hackage: hasql-implicits-0.1.0.2@sha256:5d54e09cb779a209681b139fb3cc726bae75134557932156340cc0a56dd834a8,1361
 - completed:
-    hackage: hasql-pool-0.10@sha256:912197a328acb85505f98bb9700d61f366b87659ca45126c5c2d636687b801c3,2112
    pantry-tree:
-      sha256: b655c540a49764a8d16b62941137e295b936b96edc0785eb9250972f0f92dc47
-      size: 346
+      sha256: 6452a6ca8d395f7d810139779bb0fd16fc1dbb00f1862630bc08ef5a100430f9
+      size: 1645
+    hackage: protolude-0.3.1@sha256:1cc9e5a5c26c33a43c52b554443dd9779fef13974eaa0beec7ca6d2551b400da,2647
  original:
-    hackage: hasql-pool-0.10
+    hackage: protolude-0.3.1@sha256:1cc9e5a5c26c33a43c52b554443dd9779fef13974eaa0beec7ca6d2551b400da,2647
+- completed:
+    pantry-tree:
+      sha256: d2b8440a738719ef8430ec38fe33b129e3940e4ccf2c016a727a1110a43656bb
+      size: 1089
+    hackage: ptr-0.16.8.1@sha256:525219ec5f5da5c699725f7efcef91b00a7d44120fc019878b85c09440bf51d6,2686
+  original:
+    hackage: ptr-0.16.8.1@sha256:525219ec5f5da5c699725f7efcef91b00a7d44120fc019878b85c09440bf51d6,2686
+- completed:
+    pantry-tree:
+      sha256: a544ea95288d188e893322a8e6d68f2b1f844f772dbea1f26e5c0c1a74694f56
+      size: 4053
+    hackage: wai-extra-3.1.8@sha256:bf3dbe8f4c707b502b2a88262ed71c807220651597b76b56983f864af6197890,7280
+  original:
+    hackage: wai-extra-3.1.8@sha256:bf3dbe8f4c707b502b2a88262ed71c807220651597b76b56983f864af6197890,7280
+- completed:
+    pantry-tree:
+      sha256: 52b5abf5c4c09bcfbc06e01f761a75c32cbd3e6ba23c8843981933fcc31ed53c
+      size: 474
+    hackage: wai-logger-2.3.7@sha256:19a0dc5122e22d274776d80786fb9501956f5e75b8f82464bbdad5604d154d82,1671
+  original:
+    hackage: wai-logger-2.3.7@sha256:19a0dc5122e22d274776d80786fb9501956f5e75b8f82464bbdad5604d154d82,1671
+- completed:
+    pantry-tree:
+      sha256: 99ff839445ba2c9e29a294b45904e3f4575336c7d2b4504ce310d611661c761d
+      size: 3973
+    hackage: warp-3.3.19@sha256:c6a47029537d42844386170d732cdfe6d85b2f4279bbaefdd9b50caff6faeebb,10910
+  original:
+    hackage: warp-3.3.19@sha256:c6a47029537d42844386170d732cdfe6d85b2f4279bbaefdd9b50caff6faeebb,10910
 snapshots:
 - completed:
-    sha256: 4905c93319aa94aa53da8f41d614d7bacdbfe6c63a8c6132d32e6e62f24a9af4
-    size: 649315
-    url: https://raw.githubusercontent.com/commercialhaskell/stackage-snapshots/master/lts/20/6.yaml
-  original: lts-20.6
+    sha256: 87842ecbaa8ca9cee59a7e6be52369dbed82ed075cb4e0d152614a627e8fd488
+    size: 586069
+    url: https://raw.githubusercontent.com/commercialhaskell/stackage-snapshots/master/lts/18/14.yaml
+  original: lts-18.14
@@ -8,17 +8,10 @@ import Protolude
 main :: IO ()
 main =
  doctest
-    [ "-XOverloadedStrings"
+    [ "--verbose"
+    , "-XOverloadedStrings"
    , "-XNoImplicitPrelude"
    , "-XStandaloneDeriving"
-    , "-XDuplicateRecordFields"
    , "-isrc"
-    , "src/PostgREST/Query/SqlFragment.hs"
-    , "src/PostgREST/ApiRequest/Preferences.hs"
-    , "src/PostgREST/ApiRequest/QueryParams.hs"
-    , "src/PostgREST/Error.hs"
-    , "src/PostgREST/MediaType.hs"
-    , "src/PostgREST/Config.hs"
-    , "src/PostgREST/Plan.hs"
-    , "src/PostgREST/Response.hs"
+    , "src/PostgREST/Request/Preferences.hs"
    ]
--- a/Show More
+++ b/Show More
Author	SHA1	Message	Date
Laurence IslaandGitHub	39e3246623	Upgrade protolude to 0.3.1 (#2306 )	2022-06-08 16:15:56 -05:00
steve-chavez	120ed06134	bump version to 9.0.1 * Format CHANGELOG	2022-06-03 22:19:16 -05:00
steve-chavez	a8452e7a2e	fix: using CPU while idle	2022-06-03 22:19:16 -05:00
steve-chavez	f7a2220159	fix: disable parallel GC for perf on high-core CPU	2022-06-03 22:19:16 -05:00
Laurence IslaandSteve Chavez	d8085d41fb	ci: run on branches starting with "rel-"	2022-06-03 22:19:16 -05:00
Laurence IslaandSteve Chavez	13d343bdbf	ci: Run ARM builds on releases	2022-06-03 22:19:16 -05:00
Laurence IslaandSteve Chavez	6fc47aa525	ci: Fix Windows build using Stack Added PostgreSQL binaries to the PATH and removed the use of msys2-keyring	2022-06-03 22:19:16 -05:00
dependabot[bot]andSteve Chavez	02eb3f0612	build(deps): bump codecov/codecov-action from 3.0.0 to 3.1.0 Bumps [codecov/codecov-action](https://github.com/codecov/codecov-action) from 3.0.0 to 3.1.0. - [Release notes](https://github.com/codecov/codecov-action/releases) - [Changelog](https://github.com/codecov/codecov-action/blob/master/CHANGELOG.md) - [Commits](https://github.com/codecov/codecov-action/compare/v3.0.0...v3.1.0) --- updated-dependencies: - dependency-name: codecov/codecov-action dependency-type: direct:production update-type: version-update:semver-minor ... Signed-off-by: dependabot[bot] <support@github.com>	2022-06-03 22:19:16 -05:00
Laurence IslaandSteve Chavez	3119c52cb7	ci: remove armv7 architectures for ARM builds Now only builds aarch64 on the remote server without Docker	2022-06-03 22:19:16 -05:00
Laurence IslaandSteve Chavez	74678391c6	Add CI for ARM architectures (#2127 )	2022-06-03 22:19:16 -05:00
Laurence IslaandSteve Chavez	d16972e8da	Fix misleading disambiguation error where `relationship` looks like valid syntax * Add columns for the m2m relationship	2022-06-03 22:19:16 -05:00
dependabot[bot]andSteve Chavez	0f5caa50c6	build(deps): bump codecov/codecov-action from 2.1.0 to 3.0.0 Bumps [codecov/codecov-action](https://github.com/codecov/codecov-action) from 2.1.0 to 3.0.0. - [Release notes](https://github.com/codecov/codecov-action/releases) - [Changelog](https://github.com/codecov/codecov-action/blob/master/CHANGELOG.md) - [Commits](https://github.com/codecov/codecov-action/compare/v2.1.0...v3.0.0) --- updated-dependencies: - dependency-name: codecov/codecov-action dependency-type: direct:production update-type: version-update:semver-major ... Signed-off-by: dependabot[bot] <support@github.com>	2022-06-03 22:19:16 -05:00
dependabot[bot]andSteve Chavez	176db06168	build(deps): bump actions/cache from 2.1.7 to 3 Bumps [actions/cache](https://github.com/actions/cache) from 2.1.7 to 3. - [Release notes](https://github.com/actions/cache/releases) - [Commits](https://github.com/actions/cache/compare/v2.1.7...v3) --- updated-dependencies: - dependency-name: actions/cache dependency-type: direct:production update-type: version-update:semver-major ... Signed-off-by: dependabot[bot] <support@github.com>	2022-06-03 22:19:16 -05:00
Laurence IslaandSteve Chavez	3ee3bcd7ae	Bypass FreeBSD builds due to timeouts	2022-06-03 22:19:16 -05:00
Ezequiel AlvarezandSteve Chavez	113c487db2	fix: json/jsonb columns should not have type "string" in OpenAPI spec (#2203 ) * Switch to no type for json/jsonb	2022-06-03 22:19:16 -05:00
dependabot[bot]andSteve Chavez	6876fbb0aa	build(deps): bump actions/checkout from 2.4.0 to 3 (#2186 )	2022-06-03 22:19:16 -05:00
dependabot[bot]andSteve Chavez	b8b486740c	build(deps): bump actions/upload-artifact from 2.3.1 to 3 (#2187 )	2022-06-03 22:19:16 -05:00
dependabot[bot]andSteve Chavez	83496fbcb8	build(deps): bump actions/download-artifact from 2.1.0 to 3 (#2185 )	2022-06-03 22:19:16 -05:00
Laurence IslaandSteve Chavez	ebc26d0c09	fix: Using GET with certain Content-Type headers now correctly calls the no parameter function if it exists Using GET with text/plain or application/octet-stream as Content-Type headers no longer returns 404 Not Found when a function with no parameters exists	2022-06-03 22:19:16 -05:00
Steve Chavez	dd8a2c8979	fix: Keep working when EMFILE is reached (#2158 ) Done by upgrading to warp 3.3.19	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	7cc8502a64	fix: Remove aggregates, procedures and window functions from schema cache and OpenAPI output Aggregates and Window functions can't be called as RPCs in a useful way. Procedures are not supported right now, but might be added later. Resolves #2101 Signed-off-by: Wolfgang Walther <walther@technowledgy.de>	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	5a88161ff7	fix: Take PG version into account in --dump-schema The PG version is only read by the Connection Worker, which is not used in the case dump-schema. Now, the pg version is read in the schema cache queries directly, avoiding this problem in all cases. Signed-off-by: Wolfgang Walther <walther@technowledgy.de>	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	973c22a102	ci: Fix windows build failing because of outdated keyring Signed-off-by: Wolfgang Walther <walther@technowledgy.de>	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	2c001010df	fix: Remove trigger functions from schema cache and OpenAPI output Trigger functions can't be called directly from SQL and can't be called via the /rpc prefix either - it makes no sense to expose them in the OpenAPI output. And we don't need to cache them in the schema cache either. Best practice would be to keep the trigger functions in a non-exposed schema anyway.	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	a36c5ce52d	ci: Add -with-rtsopts=-KxK option to prevent introducing space leaks Resolves #387	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	8bfbf9eb89	Align columns in postgrest.cabal	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	2e334db31b	fix: Read database configuration properly when `=` is present in value Resolves #2120	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	d1851a6966	refactor: Reformat db-config query	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	76fdf29f5c	refactor: Move each Wai Middleware to a separate file	2022-06-03 22:19:16 -05:00
Steve Chavez	490f631011	cov: empty coverage overlay (#2119 ) The overlay depended on the version number, which caused errors when upgrading. Also update cabal description.	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	685acccf6d	test: Reorganize test/ folder into one subdirectory for each test type	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	9378de558f	Remove unused dependencies from postgrest.cabal	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	747b0234ae	cov: Add coverage overlay for impossible case in corsPolicy	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	ce578ec1b8	refactor: simplify logger middleware	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	7272d8894c	cov: Remove unreachable static icon	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	de8253facc	cov: Add tests for request logging	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	a15118576d	test: Remove unused unix-socket.config file Unix sockets are the default in io tests and we are testing ip connections explicitly.	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	0a44125d92	test: Improve io test perfomance Local test improves performance by 15%.	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	9c9e25b2af	test: Move io-tests SQL fixtures to a separate file	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	ce6ea74ee1	test: Improve log output for failing io-tests	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	e8e3349a71	test: Refactor invalid_role_claim_key_notify_reload test to properly read all available input	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	06a9794448	test: Use .encode() end .decode default values in io-tests Those default to "utf-8" anyway.	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	30a6ae6241	nix: Fix nested postgrest-with-postgresql-x calls when -f is used	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	c228c37619	Remove outdated heroku manifest	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	9f09a6547d	cov: Improve jwt claims test-cases	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	130dcc4f66	fix: Fix wrong CORS header Authentication -> Authorization Also refactors defaultCorsPolicy and corsPolicy and cleans up CORS tests	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	7db4a75146	fix: Make recursive view parsing work with XMLTABLE + DEFAULT	2022-06-03 22:19:16 -05:00
dependabot[bot]andSteve Chavez	eedfe957b5	build(deps): bump actions/upload-artifact from 2.3.0 to 2.3.1 (#2094 )	2022-06-03 22:19:16 -05:00
Steve Chavez	ef240ef05a	fix: `is` not working with upper/mixed case values (#2081 )	2022-06-03 22:19:16 -05:00
dependabot[bot]andSteve Chavez	89e93ef6f5	build(deps): bump actions/upload-artifact from 2.2.4 to 2.3.0 Bumps [actions/upload-artifact](https://github.com/actions/upload-artifact) from 2.2.4 to 2.3.0. - [Release notes](https://github.com/actions/upload-artifact/releases) - [Commits](https://github.com/actions/upload-artifact/compare/v2.2.4...v2.3.0) --- updated-dependencies: - dependency-name: actions/upload-artifact dependency-type: direct:production update-type: version-update:semver-minor ... Signed-off-by: dependabot[bot] <support@github.com>	2022-06-03 22:19:16 -05:00
dependabot[bot]andSteve Chavez	1307d00df2	build(deps): bump actions/download-artifact from 2.0.10 to 2.1.0 Bumps [actions/download-artifact](https://github.com/actions/download-artifact) from 2.0.10 to 2.1.0. - [Release notes](https://github.com/actions/download-artifact/releases) - [Commits](https://github.com/actions/download-artifact/compare/v2.0.10...v2.1.0) --- updated-dependencies: - dependency-name: actions/download-artifact dependency-type: direct:production update-type: version-update:semver-minor ... Signed-off-by: dependabot[bot] <support@github.com>	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	9c7e6070f0	fix: Dump db-config option without quotes as it's a boolean	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	3c8e309a32	nix(feat): Add postgrest-git-hooks to enable pre-commit and pre-push hooks	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	7940e73a12	nix: Add weeder to postgrest-coverage Removes a bit of dead code from SpecHelper.hs	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	9b397878dc	refactor: Make asJsonSingleF "safe", by accessing only the first element of a json_agg result	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	eda59c241e	fix: Execute deferred constraint triggers when using `Prefer: tx=rollback` Resolves #2020	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	4d64aae870	fix: Link to latest docs in pre-release openapi output Resolves #2018	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	e337891c89	ci: Use matrix strategy to test against postgres versions	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	d8f03e37ae	ci: Run IO tests against all postgres versions Resolves #1820.	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	0d99789938	ci: Disable update of dockerhub description on release This is not allowed via personal access token right now and could be re-enabled in the future, once solved by docker hub.	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	88674c5af6	nix(feat): Add bash completion for git references	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	1aebe62a03	nix(feat): Add `postgrest-loadtest`	2022-06-03 22:19:16 -05:00
Wolfgang WaltherandSteve Chavez	f7b3608d4e	nix(feat): Add `postgrest-with-git` and `postgrest-with-pgrst` tools	2022-06-03 22:19:16 -05:00