Postgres instance on CI.

.github/workflows/all-test.yml

@@ -46,6 +46,19 @@ jobs:
       matrix:
         shard: [0, 1, 2, 3, 4, 5, 6, 7]
     runs-on: ubuntu-latest
+    services:
+      postgres:
+        image: postgres
+        env:
+          POSTGRES_PASSWORD: postgres
+        # Set health checks to wait until postgres has started
+        options: >-
+          --health-cmd pg_isready
+          --health-interval 10s
+          --health-timeout 5s
+          --health-retries 5
+        ports:
+          - 5432:5432
     steps:
     - name: Cache PUB_CACHE
       uses: actions/cache@0057852bfaa89a56745cba8c7296529d2fc39830
@@ -63,6 +76,8 @@ jobs:
       run: sudo apt-get update -yq && sudo apt-get install webp
     - run: dart test -P presubmit --shard-index ${{matrix.shard}} --total-shards 8
       working-directory: app/
+      env:
+        PUB_POSTGRES_URL: postgresql://postgres:postgres@localhost:5432/postgres?sslmode=disable
 
   define_pkg_list:
     runs-on: ubuntu-latest

app/lib/shared/env_config.dart

@@ -50,6 +50,9 @@ class _EnvConfig {
   late final fakeEmailSenderOutputDir =
       Platform.environment['FAKE_EMAIL_SENDER_OUTPUT_DIR'];
 
+  /// When specified, the server will connect to this URL for postgres database connections.
+  late final pubPostgresUrl = Platform.environment['PUB_POSTGRES_URL'];
+
   /// True, if running inside AppEngine.
   bool get isRunningInAppengine => _gaeService != null && _gaeVersion != null;
 

app/pubspec.yaml

@@ -49,6 +49,7 @@ dependencies:
   pana: '0.22.23'
   # 3rd-party packages with pinned versions
   mailer: '6.5.0'
+  postgres: '3.5.8'
   ulid: '2.0.1'
   tar: '2.0.0'
   api_builder:

app/test/shared/postgresql_ci_test.dart

@@ -0,0 +1,36 @@
+// Copyright (c) 2025, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:clock/clock.dart';
+import 'package:postgres/postgres.dart';
+import 'package:pub_dev/shared/env_config.dart';
+import 'package:test/test.dart';
+
+void main() {
+  group('Postgresql connection on CI', () {
+    test('connects to CI instance', () async {
+      final pubPostgresUrl = envConfig.pubPostgresUrl;
+      if (pubPostgresUrl == null) {
+        markTestSkipped('PUB_POSTGRES_URL was not specified.');
+        return;
+      }
+      try {
+        await Connection.open(
+          Endpoint(host: 'localhost', database: 'postgres'),
+        );
+      } catch (e, st) {
+        print(e);
+        print(st);
+      }
+      final conn = await Connection.openFromUrl(pubPostgresUrl);
+      final rs1 = await conn.execute('SELECT 1;');
+      expect(rs1[0][0], 1);
+
+      final dbName =
+          'pubtemp_${clock.now().millisecondsSinceEpoch.toRadixString(36)}';
+      await conn.execute('CREATE DATABASE $dbName');
+      await conn.execute('DROP DATABASE $dbName');
+    });
+  });
+}

pubspec.lock

@@ -73,6 +73,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "2.1.2"
+  buffer:
+    dependency: transitive
+    description:
+      name: buffer
+      sha256: "389da2ec2c16283c8787e0adaede82b1842102f8c8aae2f49003a766c5c6b3d1"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.2.3"
   build:
     dependency: transitive
     description:
@@ -649,6 +657,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "1.5.1"
+  postgres:
+    dependency: transitive
+    description:
+      name: postgres
+      sha256: "96d7f40e079b96cdbfed13d71c64668cfd79c35bc17223c6b3ac0ca63bff72f0"
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.5.8"
   protobuf:
     dependency: transitive
     description: