Add Postgres commit sha to Postgres version (#4603)

## Problem

Ref https://neondb.slack.com/archives/C036U0GRMRB/p1688122168477729

## Summary of changes
- Add sha from postgres repo into postgres version string (via
`--with-extra-version`)
- Add a test that Postgres version matches the expected one
- Remove build-time hard check and allow only related tests to fail

.github/workflows/build_and_test.yml

@@ -236,27 +236,6 @@ jobs:
           submodules: true
           fetch-depth: 1
 
-      - name: Check Postgres submodules revision
-        shell: bash -euo pipefail {0}
-        run: |
-          # This is a temporary solution to ensure that the Postgres submodules revision is correct (i.e. the updated intentionally).
-          # Eventually it will be replaced by a regression test https://github.com/neondatabase/neon/pull/4603
-
-          FAILED=false
-          for postgres in postgres-v14 postgres-v15 postgres-v16; do
-            expected=$(cat vendor/revisions.json | jq --raw-output '."'"${postgres}"'"')
-            actual=$(git rev-parse "HEAD:vendor/${postgres}")
-            if [ "${expected}" != "${actual}" ]; then
-              echo >&2 "Expected ${postgres} rev to be at '${expected}', but it is at '${actual}'"
-              FAILED=true
-            fi
-          done
-
-          if [ "${FAILED}" = "true" ]; then
-            echo >&2 "Please update vendor/revisions.json if these changes are intentional"
-            exit 1
-          fi
-
       - name: Set pg 14 revision for caching
         id: pg_v14_rev
         run: echo pg_rev=$(git rev-parse HEAD:vendor/postgres-v14) >> $GITHUB_OUTPUT

Makefile

@@ -81,11 +81,14 @@ $(POSTGRES_INSTALL_DIR)/build/%/config.status:
 		echo "'git submodule update --init --recursive --depth 2 --progress .' in project root.\n"; \
 		exit 1; }
 	mkdir -p $(POSTGRES_INSTALL_DIR)/build/$*
-	(cd $(POSTGRES_INSTALL_DIR)/build/$* && \
-	env PATH="$(EXTRA_PATH_OVERRIDES):$$PATH" $(ROOT_PROJECT_DIR)/vendor/postgres-$*/configure \
+
+	VERSION=$*; \
+	EXTRA_VERSION=$$(cd $(ROOT_PROJECT_DIR)/vendor/postgres-$$VERSION && git rev-parse HEAD); \
+	(cd $(POSTGRES_INSTALL_DIR)/build/$$VERSION && \
+	env PATH="$(EXTRA_PATH_OVERRIDES):$$PATH" $(ROOT_PROJECT_DIR)/vendor/postgres-$$VERSION/configure \
 		CFLAGS='$(PG_CFLAGS)' \
-		$(PG_CONFIGURE_OPTS) \
-		--prefix=$(abspath $(POSTGRES_INSTALL_DIR))/$* > configure.log)
+		$(PG_CONFIGURE_OPTS) --with-extra-version=" ($$EXTRA_VERSION)" \
+		--prefix=$(abspath $(POSTGRES_INSTALL_DIR))/$$VERSION > configure.log)
 
 # nicer alias to run 'configure'
 # Note: I've been unable to use templates for this part of our configuration.

test_runner/fixtures/neon_fixtures.py

@@ -982,7 +982,7 @@ class NeonEnv:
 
     Some notable functions and fields in NeonEnv:
 
-    postgres - A factory object for creating postgres compute nodes.
+    endpoints - A factory object for creating postgres compute nodes.
 
     pageservers - An array containing objects representing the pageservers
 

test_runner/regress/test_postgres_version.py

@@ -0,0 +1,35 @@
+import json
+import re
+from pathlib import Path
+
+from fixtures.neon_fixtures import PgBin
+from fixtures.pg_version import PgVersion
+
+
+def test_postgres_version(base_dir: Path, pg_bin: PgBin, pg_version: PgVersion):
+    """Test that Postgres version matches the one we expect"""
+
+    with (base_dir / "vendor" / "revisions.json").open() as f:
+        expected_revisions = json.load(f)
+
+    output_prefix = pg_bin.run_capture(["postgres", "--version"], with_command_header=False)
+    stdout = Path(f"{output_prefix}.stdout")
+    assert stdout.exists(), "postgres --version didn't print anything to stdout"
+
+    with stdout.open() as f:
+        output = f.read().strip()
+
+    # `postgres --version` prints something like "postgres (PostgreSQL) 15.6 (85d809c124a898847a97d66a211f7d5ef4f8e0cb)".
+    pattern = r"postgres \(PostgreSQL\) (?P<version>\d+\.\d+) \((?P<commit>[0-9a-f]{40})\)"
+    match = re.search(pattern, output, re.IGNORECASE)
+    assert match is not None, f"Can't parse {output} with {pattern}"
+
+    version = match.group("version")
+    commit = match.group("commit")
+
+    assert (
+        pg_version.v_prefixed in expected_revisions
+    ), f"Version `{pg_version.v_prefixed}` doesn't exist in `vendor/revisions.json`, please update it if these changes are intentional"
+
+    msg = f"Unexpected Postgres {pg_version} version: `{output}`, please update `vendor/revisions.json` if these changes are intentional"
+    assert [version, commit] == expected_revisions[pg_version.v_prefixed], msg

vendor/revisions.json

@@ -1,5 +1,5 @@
 {
-  "postgres-v16": "8ef3c33aa01631e17cb24a122776349fcc777b46",
-  "postgres-v15": "f0d6b0ef7581bd78011832e23d8420a7d2c8a83a",
-  "postgres-v14": "d6f7e2c604bfc7cbc4c46bcea0a8e800f4bc778a"
+  "v16": ["16.2", "8ef3c33aa01631e17cb24a122776349fcc777b46"],
+  "v15": ["15.6", "f0d6b0ef7581bd78011832e23d8420a7d2c8a83a"],
+  "v14": ["14.11", "d6f7e2c604bfc7cbc4c46bcea0a8e800f4bc778a"]
 }