nix: Build static postgrest executable via pkgsStatic

This replaces the build via static-haskell-nix and will hopefully make
it possible to cross compile in the future.

default.nix

@@ -36,7 +36,7 @@ let
       allOverlays.build-toolbox
       allOverlays.checked-shell-script
       allOverlays.gitignore
-      (allOverlays.postgresql-default { inherit patches; })
+      allOverlays.postgresql-default
       allOverlays.postgresql-legacy
       allOverlays.postgresql-future
       allOverlays.postgis
@@ -60,23 +60,11 @@ let
       { name = "postgresql-9.6"; postgresql = pkgs.postgresql_9_6.withPackages (p: [ p.postgis p.pg_safeupdate ]); }
     ];
 
-  patches =
-    pkgs.callPackage nix/patches { };
-
   # Dynamic derivation for PostgREST
   postgrest =
     pkgs.haskell.packages."${compiler}".callCabal2nix name src { };
 
-  # Functionality that derives a fully static Haskell package based on
+  staticHaskellPackage = import nix/static.nix { inherit compiler name pkgs src; };
-  # 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;
 
   # Options passed to cabal in dev tools and tests
   devCabalOptions =
@@ -160,8 +148,8 @@ rec {
     };
 } // pkgs.lib.optionalAttrs pkgs.stdenv.isLinux rec {
   # Static executable.
-  inherit postgrestStatic;
+  inherit (staticHaskellPackage) postgrestStatic;
-  inherit packagesStatic;
+  inherit (staticHaskellPackage) packagesStatic;
 
   # Docker images and loading script.
   docker =

nix/UPGRADE.md

@@ -33,15 +33,6 @@ postgrest-nixpkgs-upgrade
 
 ```
 
-## Update pinned version of `static-haskell-nix`
-
-We pin [`static-haskell-nix`](https://github.com/nh2/static-haskell-nix) in
-[`nix/static-haskell-package.nix`](static-haskell-package.nix). Upgrade the
-pinned revision and the tarball hash if necessary. See
-[`nix/nixpkgs-upgrade.nix`](nixpkgs-upgrade.nix) for how to get the correct
-tarball hash, or just change the hash to an arbitrary value of correct length,
-run `nix-build` and use the expected value from the resulting error message.
-
 ## Review overlays
 
 Check whether the individual [overlays](overlays) are still required.

nix/overlays/postgresql-default.nix

@@ -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 ? [ ], ... }: {
+  postgresql = super.postgresql_15;
-    patches = patches ++ [ postgresql-atexit ];
-  });
 }

nix/patches/default.nix

@@ -1,29 +0,0 @@
-{ runCommand }:
-
-{
-  applyPatches =
-    name: src: patches:
-    runCommand
-      name
-      { inherit src patches; }
-      ''
-        set -eou pipefail
-
-        cp -r $src $out
-        chmod -R u+w $out
-
-        for patch in $patches; do
-          echo "Applying patch $patch"
-          patch -d "$out" -p1 < "$patch"
-        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;
-}

nix/patches/postgresql-atexit.patch

@@ -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

nix/patches/static-haskell-nix-ghc-bignum.patch

@@ -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.

nix/patches/static-haskell-nix-ncurses.patch

@@ -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,

nix/patches/static-haskell-nix-openssl.patch

@@ -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; });
- 

nix/static-haskell-package.nix

@@ -1,65 +0,0 @@
-# Derive a fully static Haskell package based on musl instead of glibc.
-{ nixpkgs, system, compiler, patches, allOverlays }:
-
-name: src:
-let
-  # The nh2/static-haskell-nix project does all the hard work for us.
-  static-haskell-nix =
-    let
-      rev = "bd66b86b72cff4479e1c76d5916a853c38d09837";
-    in
-    builtins.fetchTarball {
-      url = "https://github.com/nh2/static-haskell-nix/archive/${rev}.tar.gz";
-      sha256 = "0rnsxaw7v27znsg9lgqk1i4007ydqrc8gfgimrmhf24lv6galbjh";
-    };
-
-  patched-static-haskell-nix =
-    patches.applyPatches "patched-static-haskell-nix"
-      static-haskell-nix
-      [
-        patches.static-haskell-nix-ncurses
-        patches.static-haskell-nix-ghc-bignum
-        patches.static-haskell-nix-openssl
-      ];
-
-  extraOverrides =
-    final: prev:
-    rec {
-      # We need to add our package needs to the package set that we pass to
-      # static-haskell-nix. Using callCabal2nix on the haskellPackages that
-      # it returns would result in a dynamic build based on musl, and not the
-      # fully static build that we want.
-      "${name}" = prev.callCabal2nix name src { };
-    };
-
-  overlays =
-    [
-      allOverlays.postgresql-future
-      (allOverlays.postgresql-default { inherit patches; })
-      (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
-      # tests)
-      (self: super:
-        { postgresql = super.postgresql.overrideAttrs (_: { doCheck = false; }); }
-      )
-    ];
-
-  # Apply our overlay to nixpkgs.
-  normalPkgs =
-    import nixpkgs { inherit overlays system; };
-
-  defaultCabalPackageVersionComingWithGhc =
-    {
-      ghc948 = "Cabal_3_8_1_0";
-    }."${compiler}";
-
-  # The static-haskell-nix 'survey' derives a full static set of Haskell
-  # packages, applying fixes where necessary.
-  survey =
-    import "${patched-static-haskell-nix}/survey" { inherit normalPkgs compiler defaultCabalPackageVersionComingWithGhc; };
-in
-{
-  inherit survey;
-  package = survey.haskellPackages."${name}";
-}

nix/static.nix

@@ -0,0 +1,68 @@
+{ compiler
+, name
+, pkgs
+, src
+}:
+let
+  # This builds a static PostgREST exectuable based on pkgsStatic.
+  # pkgsStatic is based on musl, so is a kind of cross-compilation.
+  # We still make this explicit here via pkgsCross, because we need
+  # to get postgresql/libpq for musl, too.
+  pkgsCross = pkgs.pkgsCross.musl64;
+  inherit (pkgsCross) pkgsStatic;
+  inherit (pkgsStatic.haskell) lib;
+
+  # postgresql doesn't build in the fully static overlay - but the default
+  # derivation is built with static libraries anyway.
+  libpq = (pkgsCross.postgresql.override {
+    # disable server-side only stuff to improve compilation times
+    enableSystemd = false;
+    jitSupport = false;
+
+    # disable gssapi support, because it leads to linking errors
+    gssSupport = false;
+  }).overrideAttrs (finalAttrs: prevAttrs: {
+    dontDisableStatic = true;
+    # Tests fail for initdb and other server-side code which we don't care about
+    doCheck = false;
+  });
+
+  packagesStatic =
+    pkgsStatic.haskell.packages."${compiler}".override (old: {
+      ghc = pkgsStatic.pkgsBuildHost.haskell.compiler."${compiler}".override {
+        # Using the bundled libffi generally works better for cross-compiling
+        libffi = null;
+        # Building sphinx fails on some platforms
+        enableDocs = false;
+        # Cross compiling with native bignum works better than with gmp
+        enableNativeBignum = true;
+      };
+
+      overrides = pkgs.lib.composeExtensions old.overrides (final: prev: {
+        postgresql-libpq = (prev.postgresql-libpq.override {
+          postgresql = libpq;
+        }).overrideAttrs (finalAttrs: prevAttrs: {
+          # Using use-pkg-config flag, because pg_config won't work when cross-compiling
+          configureFlags = prevAttrs.configureFlags ++ [ "-fuse-pkg-config" ];
+          # Using pkg-config without pkgsCross, because "pkg-config" is hardcoded in
+          # postgresql-libpq's Setup.hs. Using pkgsStatic to make pkg-config return the
+          # static libs for libpq.
+          nativeBuildInputs = prevAttrs.nativeBuildInputs ++ [ pkgs.pkgsStatic.pkg-config ];
+
+          buildInputs = [
+            pkgsStatic.openssl
+          ];
+        });
+      });
+    });
+
+  makeExecutableStatic = drv:
+    lib.justStaticExecutables
+      (lib.appendConfigureFlag drv "--enable-executable-static");
+
+in
+{
+  inherit packagesStatic;
+
+  postgrestStatic = makeExecutableStatic (packagesStatic.callCabal2nix name src { });
+}