add pgmq SQL only extension

Author: olirice

flake.nix

@@ -94,6 +94,7 @@
           ./nix/ext/pgroonga.nix
           ./nix/ext/index_advisor.nix
           ./nix/ext/wal2json.nix
+          ./nix/ext/pgmq.nix
           ./nix/ext/pg_repack.nix
           ./nix/ext/pg-safeupdate.nix
           ./nix/ext/plpgsql-check.nix

nix/docs/migration-tests.md

@@ -43,8 +43,8 @@ compare, and you could do something like the following:
 OLD_GIT_VERSION=...
 NEW_GIT_VERSION=...
 
-nix run github:supabase/nix-postgres#migration-test \
-  $(nix build "github:supabase/nix-postgres/$OLD_GIT_VERSION#psql_14/bin") \
-  $(nix build "github:supabase/nix-postgres/$NEW_GIT_VERSION#psql_14/bin") \
+nix run github:supabase/nix-postgres#migration-test wrappers \
+  $(nix build "github:supabase/postgres/$OLD_GIT_VERSION#psql_14/bin") \
+  $(nix build "github:supabase/postgres/$NEW_GIT_VERSION#psql_14/bin") \
   pg_upgrade
 ```

nix/ext/pgmq.nix

@@ -0,0 +1,35 @@
+{ lib, stdenv, fetchFromGitHub, postgresql }:
+
+stdenv.mkDerivation rec {
+  pname = "pgmq";
+  version = "1.4.0";
+
+  buildInputs = [ postgresql ];
+
+  src = fetchFromGitHub {
+    owner  = "tembo-io";
+    repo   = pname;
+    rev    = "v${version}";
+    hash = "sha256-k7iKp2CZY3M8POUqIOIbKxrofoOfn2FxfVW01KYojPA=";
+  };
+
+  buildPhase = ''
+    cd pgmq-extension
+  '';
+
+  installPhase = ''
+    mkdir -p $out/{lib,share/postgresql/extension}
+
+    mv sql/pgmq.sql $out/share/postgresql/extension/pgmq--${version}.sql
+    cp sql/*.sql $out/share/postgresql/extension
+    cp *.control $out/share/postgresql/extension
+  '';
+
+  meta = with lib; {
+    description = "A lightweight message queue. Like AWS SQS and RSMQ but on Postgres.";
+    homepage    = "https://github.com/tembo-io/pgmq";
+    maintainers = with maintainers; [ olirice ];
+    platforms   = postgresql.meta.platforms;
+    license     = licenses.postgresql;
+  };
+}

nix/tests/migrations/wrappers.sql

@@ -0,0 +1,6 @@
+if version > 0.3.1
+
+	create fdw .... stripe
+
+if version > 0.4.1
+	create fdw ... wasm