Persistence growns without control

[JCKodel]

On MacOS, every time I restart a project (i.e.: the 🔃 button on VSCode), a new persistence entry is added in firebase_auth.hive.

Currently, I have 24 entries that are all the same user (i.e.: every time the project starts, it loads the previous user from storage and then save it again, as a new row, making the firebase_auth.hive file to grow.

This is how I'm using it:

On main.dart:

await [
  FirebaseDartFlutter.setup(),
  dotenv.load(fileName: ".env.${kDebugMode ? "debug" : "release"}"),
].wait;

final firebaseOptions = FirebaseOptions(
  appId: dotenv.FIREBASE_APP_ID,
  apiKey: dotenv.FIREBASE_API_KEY,
  projectId: dotenv.FIREBASE_PROJECT_ID,
  messagingSenderId: dotenv.MESSAGING_SENDER_ID,
  authDomain: dotenv.FIREBASE_AUTH_DOMAIN,
  androidClientId: dotenv.FIREBASE_ANDROID_CLIENT_ID,
  iosBundleId: dotenv.FIREBASE_IOS_BUNDLE_ID,
  storageBucket: dotenv.FIREBASE_STORAGE_BUCKET,
  iosClientId: dotenv.FIREBASE_IOS_CLIENT_ID,
);

final tasks = await <Future<dynamic>>[
  I18n.loadLocale(),
  Firebase.initializeApp(options: firebaseOptions),
].wait;

final firebaseApp = tasks[1] as FirebaseApp;

await authService.initialize(firebaseApp);

So, basically, calling FirebaseDartFlutter.setup(), then Firebase.initializeApp(options: firebaseOptions), then initializing my authService as:

final class AuthService extends ChangeNotifier {
  AuthService._();

  final _logger = Logger("${AuthService}");
  late final FirebaseAuth _firebaseAuth;

  String _userId = "";
  String get userId => _userId;
  Completer<User?>? _initializationCompleter;

  Future<void> initialize(FirebaseApp firebaseApp) async {
    _logger.info("Initializing ${AuthService}");
    _firebaseAuth = FirebaseAuth.instanceFor(app: firebaseApp);
    _initializationCompleter = Completer<User?>();
    _firebaseAuth.authStateChanges().listen(_onAuthStateChanged);
    await _initializationCompleter!.future;
    _initializationCompleter = null;
    _userId = _firebaseAuth.currentUser?.uid ?? "";
  }

  void _onAuthStateChanged(User? user) {
    if (_initializationCompleter != null) _initializationCompleter!.complete(user);

    if (user == null && _userId.isNotEmpty) {
      _userId = "";
      notifyListeners();
    }
  }

Needed to add that Completer hack because of #62

So, every time the project starts or I restart it from the 🔃 button on VSCode, a new entry is added to the hive database (there is no operation whatsoever, no new login or logout).

EDIT:

I think the code responsible to write to persistence is

firebase_dart/packages/firebase_dart/lib/src/auth/usermanager.dart

Line 57 in 105c572

Future<void> setCurrentUser(User? currentUser) async {

, which is, in theory, correct.

But, somehow, hive is saving the same ID repeatedly:

Because of this, currently, my firebase_auth.hive is 80Kb (and there is only a single login with email and password).

EDIT 2:

final hiveBox = await Hive.openBox<String>("firebase_auth");

await hiveBox.compact();

This solves the issue. I recommend to compact the database on initialization (or after storing the user), so it would not grow unchecked. Or, better yet, stop using Hive (it sucks, a lot, alternative: https://pub.dev/packages/reaxdb_dart or just write in SharedPreferences) Better yet: let us handle persistence by implementing an interface (NHost does that with an interface https://github.com/nhost/nhost-dart/blob/main/packages/nhost_sdk/lib/src/base/auth_store.dart that can be provided to the initialization method: https://github.com/nhost/nhost-dart/blob/04142ec5b6d3a3340480f46b93c2ec72f1939f43/packages/nhost_flutter_auth/example/lib/persistent_auth_example.dart#L47) (so, in case we could use something like https://pub.dev/packages/flutter_secure_storage).