duplicates on socket stream listener

[muhammadyusuf-kurbonov]

Describe the bug
FlutterFeathersJS instance is the singleton. I have repository wrapper and listen method:

abstract class FeathersLocalRepo<Entity> {
  late Logger log;
  abstract String serviceName;
  Entity fromMap(Map<String, dynamic> map);

  final FlutterFeathersjs _client;

  FeathersLocalRepo({required FlutterFeathersjs client}) : _client = client {
    log = Logger('${serviceName}Repo');
  }
...
  Future<StreamSubscription<FeathersJsEventData>> listen(
    void Function(FeathersJsEventData<dynamic>) listener,
  ) async {
    await _client.waitClientBeReady();
    final id = Random().nextInt(999);
    log.info("Setup listener $id");
    return _client
        .socketListen(serviceName: serviceName, fromJson: fromMap)
        .listen((event) {
          log.info("Event received: $event on $id");
          listener(event);
        });
  }

and output:

I/flutter ( 4535): INFO: CustomerChat : 2025-09-25 15:16:02.014553: Listener setup
I/flutter ( 4535): INFO: customer-chat-messagesRepo : 2025-09-25 15:16:02.024819: Setup listener 177
I/flutter ( 4535): INFO: CustomerChat : 2025-09-25 15:16:05.904523: Listener closed // <- close page and open again
I/flutter ( 4535): INFO: CustomerChat : 2025-09-25 15:16:06.442680: Listener setup
I/flutter ( 4535): INFO: customer-chat-messagesRepo : 2025-09-25 15:16:06.446800: Setup listener 332
I/flutter ( 4535): INFO: customer-chat-messagesRepo : 2025-09-25 15:16:12.262793: Event received: Instance of 'FeathersJsEventData<dynamic>' on 332
I/flutter ( 4535): INFO: CustomerChat : 2025-09-25 15:16:12.263101: event received by subscription 738179784
I/flutter ( 4535): INFO: customer-chat-messagesRepo : 2025-09-25 15:16:12.263482: Event received: Instance of 'FeathersJsEventData<dynamic>' on 332
I/flutter ( 4535): INFO: CustomerChat : 2025-09-25 15:16:12.263550: event received by subscription 738179784
I/flutter ( 4535): INFO: CustomerChat : 2025-09-25 15:16:12.264223: Received chat message: Instance of 'NoteMessageContent'
I/flutter ( 4535): INFO: CustomerChat : 2025-09-25 15:16:12.264635: Received chat message: Instance of 'NoteMessageContent'

To Reproduce
Steps to reproduce the behavior:

1. Make FlutterFeathersJS a singleton
2. On a state/widget make listen on service
3. Open this page twice/3 times (doesn't matter navigator or self). Don't forget to close on dispose.
4. Send event after reopening. Stream will receive duplicated events

Expected behavior
Only one event

Screenshots
If applicable, add screenshots to help explain your problem.

Desktop (please complete the following information):

• OS: Android
• Browser [e.g. chrome, safari]
• Version [e.g. 22]

Smartphone (please complete the following information):

• Device: [e.g. iPhone6]
• OS: [e.g. iOS8.1]
• Browser [e.g. stock browser, safari]
• Version [e.g. 4.0.4]

Additional context
Add any other context about the problem here.

[muhammadyusuf-kurbonov]

Update:

Stream<FeathersJsEventData<T>> listen<T>(
      {required String serviceName, required Function fromJson}) {
    /// On created event
    _socket.on('$serviceName created', (createdData) {
      try {
        T? object = fromJson(createdData);
        eventBus.fire(FeathersJsEventData<T>(
            data: object, type: FeathersJsEventType.created));
      } catch (e) {
        eventBus.fire(new FeatherJsError(
            type: FeatherJsErrorType.IS_DESERIALIZATION_ERROR, error: e));
      }
    });

    /// On updated event
    _socket.on('$serviceName updated', (updatedData) {
      try {
        T? object = fromJson(updatedData);
        eventBus.fire(FeathersJsEventData<T>(
            data: object, type: FeathersJsEventType.updated));
      } catch (e) {
        eventBus.fire(new FeatherJsError(
            type: FeatherJsErrorType.IS_DESERIALIZATION_ERROR, error: e));
      }
    });

    /// On patched event
    _socket.on('$serviceName patched', (patchedData) {
      try {
        T? object = fromJson(patchedData);
        eventBus.fire(FeathersJsEventData<T>(
            data: object, type: FeathersJsEventType.patched));
      } catch (e) {
        eventBus.fire(new FeatherJsError(
            type: FeatherJsErrorType.IS_DESERIALIZATION_ERROR, error: e));
      }
    });

    /// On removed event
    _socket.on('$serviceName removed', (removedData) {
      try {
        T? object = fromJson(removedData);
        eventBus.fire(FeathersJsEventData<T>(
            data: object, type: FeathersJsEventType.removed));
      } catch (e) {
        eventBus.fire(new FeatherJsError(
            type: FeatherJsErrorType.IS_DESERIALIZATION_ERROR, error: e));
      }
    });

    return eventBus.on<FeathersJsEventData<T>>();
  }

You have to clear all listeners on the result stream will be closed/cancelled.

[muhammadyusuf-kurbonov]

or move listeners's setup out of the listen function in the client class.