Do not fail Postgres init on staging or prod.

app/lib/database/database.dart

@@ -11,6 +11,7 @@ import 'package:gcloud/service_scope.dart' as ss;
 import 'package:meta/meta.dart';
 import 'package:postgres/postgres.dart';
 import 'package:pub_dev/service/secret/backend.dart';
+import 'package:pub_dev/shared/configuration.dart';
 import 'package:pub_dev/shared/env_config.dart';
 
 final _random = Random.secure();
@@ -33,11 +34,15 @@ class PrimaryDatabase {
   /// the secret backend, connects to it and registers the primary database
   /// service in the current scope.
   static Future<void> tryRegisterInScope() async {
+    if (activeConfiguration.isProduction) {
+      // Production is not configured for postgresql yet.
+      return;
+    }
     var connectionString =
         envConfig.pubPostgresUrl ??
         (await secretBackend.lookup(SecretKey.postgresConnectionString));
-    if (connectionString == null && envConfig.isRunningInAppengine) {
-      // ignore for now, must throw once we have the environment setup ready
+    if (connectionString == null && activeConfiguration.isStaging) {
+      // Staging may not have the connection string set yet.
       return;
     }
     // The scope-specific custom database. We are creating a custom database for

app/lib/frontend/handlers/pubapi.dart

@@ -9,6 +9,7 @@ import 'package:_pub_shared/data/package_api.dart';
 import 'package:_pub_shared/data/publisher_api.dart';
 import 'package:_pub_shared/data/task_api.dart';
 import 'package:api_builder/api_builder.dart';
+import 'package:pub_dev/database/database.dart';
 import 'package:pub_dev/frontend/handlers/atom_feed.dart';
 import 'package:shelf/shelf.dart';
 import 'package:shelf_router/shelf_router.dart';
@@ -457,6 +458,7 @@ class PubApi {
   Future<Response> debug(Request request) async => debugResponse({
     'package': packageDebugStats(),
     'search': searchDebugStats(),
+    'database': primaryDatabase != null,
   });
 
   @EndPoint.get('/packages.json')

app/lib/service/services.dart

@@ -14,6 +14,7 @@ import 'package:gcloud/service_scope.dart';
 import 'package:gcloud/storage.dart';
 import 'package:googleapis_auth/auth_io.dart' as auth;
 import 'package:logging/logging.dart';
+import 'package:postgres/postgres.dart';
 import 'package:pub_dev/database/database.dart';
 import 'package:pub_dev/package/api_export/api_exporter.dart';
 import 'package:pub_dev/search/handlers.dart';
@@ -251,7 +252,16 @@ Future<R> _withPubServices<R>(FutureOr<R> Function() fn) async {
           await storageService.verifyBucketExistenceAndAccess(bucketName);
         }
 
-        await PrimaryDatabase.tryRegisterInScope();
+        try {
+          await PrimaryDatabase.tryRegisterInScope();
+        } on PgException catch (e, st) {
+          if (envConfig.isRunningInAppengine) {
+            // ignore setup issues for now
+            _logger.warning('Could not connect to Postgresql database.', e, st);
+          } else {
+            rethrow;
+          }
+        }
         registerAccountBackend(AccountBackend(dbService));
         registerAdminBackend(AdminBackend(dbService));
         registerAnnouncementBackend(AnnouncementBackend());