feat: Read config directly from environment variables

resolves #1624

nix/docker/README.md

@@ -2,8 +2,8 @@
 
 In order to build an optimal PostgREST Docker image, we create the image from
 scratch (i.e., without a parent image like `debian` or `alpine`), and only
-include the files that are essential for running PostgREST (the static
-PostgREST binary and a `postgrest.conf`).
+include the file that is essential for running PostgREST: the static
+PostgREST binary.
 
 This is similar to what you would get with the following `Dockerfile`:
 
@@ -17,12 +17,6 @@ FROM scratch
 # need to include for running the application.
 ADD /absolute/path/to/postgrest /bin/postgrest
 
-# Include a default configuration file.
-ADD /absolute/path/to/postgrest.conf /etc/postgrest.conf
-
-ENV PGRST_DB_URI= \
-    ...
-
 EXPOSE 3000
 
 # This is the user id that Docker will run our image under by default. Note
@@ -32,7 +26,7 @@ EXPOSE 3000
 # can be run under any user you specify.
 USER 1000
 
-CMD [ "/bin/postgrest", "/etc/postgrest.conf" ]
+CMD [ "/bin/postgrest" ]
 ```
 
 # Building the Docker image with Nix

nix/docker/default.nix

@@ -4,9 +4,6 @@
 , checkedShellScript
 }:
 let
-  config =
-    ./postgrest.conf;
-
   image =
     dockerTools.buildImage {
       name = "postgrest";
@@ -19,34 +16,11 @@ let
 
       extraCommands =
         ''
-          mkdir etc
-          cp ${config} etc/postgrest.conf
           rmdir share
         '';
 
       config = {
-        Cmd = [ "/bin/postgrest" "/etc/postgrest.conf" ];
-        Env = [
-          "PGRST_DB_URI=postgresql://?user=postgres"
-          "PGRST_DB_SCHEMA=public"
-          "PGRST_DB_ANON_ROLE="
-          "PGRST_DB_POOL=100"
-          "PGRST_DB_POOL_TIMEOUT=10"
-          "PGRST_DB_EXTRA_SEARCH_PATH=public"
-          "PGRST_DB_CHANNEL=pgrst"
-          "PGRST_DB_CHANNEL_ENABLED=false"
-          "PGRST_SERVER_HOST=*4"
-          "PGRST_SERVER_PORT=3000"
-          "PGRST_OPENAPI_SERVER_PROXY_URI="
-          "PGRST_JWT_SECRET="
-          "PGRST_SECRET_IS_BASE64=false"
-          "PGRST_JWT_AUD="
-          "PGRST_MAX_ROWS="
-          "PGRST_PRE_REQUEST="
-          "PGRST_ROLE_CLAIM_KEY=.role"
-          "PGRST_ROOT_SPEC="
-          "PGRST_RAW_MEDIA_TYPES="
-        ];
+        Cmd = [ "/bin/postgrest" ];
         User = "1000";
         ExposedPorts = {
           "3000/tcp" = { };
@@ -65,4 +39,4 @@ buildEnv
   {
     name = "postgrest-docker";
     paths = [ load.bin ];
-  } // { inherit image config; }
+  } // { inherit image; }

nix/docker/postgrest.conf

@@ -1,30 +0,0 @@
-# See https://postgrest.org/en/stable/configuration.html#configuration
-
-# Required settings
-
-db-uri = "$(PGRST_DB_URI)"
-db-schema = "$(PGRST_DB_SCHEMA)"
-db-anon-role = "$(PGRST_DB_ANON_ROLE)"
-
-# Optional settings
-
-db-pool = "$(PGRST_DB_POOL)"
-db-pool-timeout = "$(PGRST_DB_POOL_TIMEOUT)"
-db-extra-search-path = "$(PGRST_DB_EXTRA_SEARCH_PATH)"
-
-db-channel = "$(PGRST_DB_CHANNEL)"
-db-channel-enabled = "$(PGRST_DB_CHANNEL_ENABLED)"
-
-server-host = "$(PGRST_SERVER_HOST)"
-server-port = "$(PGRST_SERVER_PORT)"
-
-openapi-server-proxy-uri = "$(PGRST_OPENAPI_SERVER_PROXY_URI)"
-jwt-secret = "$(PGRST_JWT_SECRET)"
-secret-is-base64 = "$(PGRST_SECRET_IS_BASE64)"
-jwt-aud = "$(PGRST_JWT_AUD)"
-role-claim-key = "$(PGRST_ROLE_CLAIM_KEY)"
-
-max-rows = "$(PGRST_MAX_ROWS)"
-pre-request = "$(PGRST_PRE_REQUEST)"
-root-spec = "$(PGRST_ROOT_SPEC)"
-raw-media-types = "$(PGRST_RAW_MEDIA_TYPES)"

nix/release/default.nix

@@ -94,17 +94,12 @@ let
             | ${jq}/bin/jq -r .token
         )"
 
-        # Plug the default config file into the full description.
-        defaultConfig="$(cat ${docker.config})"
-        export DEFAULT_CONFIG="$defaultConfig"
-        fullDescription="$(${envsubst}/bin/envsubst < ${fullDescription})"
-
-        # Patch the full description.
+        # Patch both descriptions.
         responseCode="$(
           ${curl}/bin/curl -s --write-out "%{response_code}" \
             --output /dev/null -H "Authorization: JWT $token" -X PATCH \
             --data-urlencode description@${description} \
-            --data-urlencode "full_description=$fullDescription" \
+            --data-urlencode full_description@${fullDescription} \
             "https://hub.docker.com/v2/repositories/$DOCKER_REPO/postgrest/"
         )"
 

nix/release/docker-hub-full-description.md

@@ -15,13 +15,8 @@ write from scratch.
 To learn how to use this container, see the [PostgREST Docker
 documentation](https://postgrest.com/en/stable/install.html#docker).
 
-You can configure the PostgREST image by setting the enviroment variables used
-in the default `/etc/postgrest.conf` file or overriding that file. This is the
-default configuration file:
-
-```
-$DEFAULT_CONFIG
-```
+You can configure the PostgREST image by setting
+[enviroment variables](https://postgrest.org/en/stable/configuration.html).
 
 # How this image is built