centrifugal / centrifuge-dart Goto Github PK

This issue will track progress of migration.

While the application was in the foreground, the following error occurred in the log records. It wasn't in the background.

Fatal Exception: io.flutter.plugins.firebase.crashlytics.FlutterError: ClientDisconnectedError
       at Transport.sendAsyncMessage(transport.dart:155)
       at ClientImpl._onPing(client.dart:711)
       at ClientImpl._onPush(client.dart:719)
       at Transport._onData.<fn>.<fn>(transport.dart:266)
       at _GrowableList.forEach(_GrowableList.java)
       at Transport._onData.<fn>(transport.dart:262)

Hello again! I noticed that RPC requests are not sent. The problem occurs when deserializing and serializing data. Shouldn't we use the type Uint8List instead of List<int>?

To clarify the situation, now the centrifuge client on Dart allows you to send RPC requests in binary form (List<int>).

Before bringing to this form, I convert the bodies of an RPC request through the .writeToBuffer() or

utf8.encode(jsonEncode(request.toProto3Json());

method, it is worth noting that the binary result of these operations is different;

What should I do to correctly send a request? A little later I will try to supplement the information about the problem I am facing.

Would it be possible to return a future for all async methods? I have noticed that some async methods return void and not Future<void> which make then non awaitable. Is this on purpose?

Ex: I would like to await connect but can't because it does not return a future:

@override
  void connect() async {
    return _connect();
  }

Here _connect returns a future, and connect would be great this way:

 Future<void> connect() async {
   return await _connect();
 }
// or the short way
 Future<void> connect() async => _connect();

Is it possible or the actual way is by design?

My publish response is throwing an exception. I am trying to catch the exception but it doesn't work:

    try {
      subscription.publish(data);
    } catch (e) {
      print(e);
    }

[VERBOSE-2:ui_dart_state.cc(209)] Unhandled Exception: Error{code: 0, message: Points already collected within 24h}
#0      Transport._processResult
package:centrifuge/src/transport.dart:148
#1      Transport.sendMessage
package:centrifuge/src/transport.dart:95
<asynchronous suspension>
#2      ClientImpl.publish
package:centrifuge/src/client.dart:183
<asynchronous suspension>

I return the error like this on my backend:

{ error: { message: e.message } }

I wonder if it would be better to not return an error but something like a custom error to now have it convert into an exception? Something like

{ result: { data: { success: false, message: "Foo" } } };

I saw this error on Firebase. I am trying to unsubscribe channel.

Fatal Exception: io.flutter.plugins.firebase.crashlytics.FlutterError: Bad state: Cannot add new events after calling close
       at _BroadcastStreamController.add(_BroadcastStreamController.java)
       at SubscriptionImpl._addUnsubscribe(subscription.dart:244)
       at SubscriptionImpl.moveToUnsubscribed(subscription.dart:173)
       at IMController.unsubscribe(im_controller.dart:157)

this is my unsubscribe code:

  Future<void> unsubscribe(String channel) async {
    var a = _imClient.getSubscription(channel);
    if (a != null) {
      await a.unsubscribe();  //line 157
      _imClient.removeSubscription(a);
    }
  }

Hi,

I am trying to implement proxy_subscribe_endpoint. The endpoint gets called on my backend on subscribe, I return a message like this:

{
  "result": {
    "data": {
      "hello": "world"
    }
  }
}

However, on the subscribeSuccessStream event I only receive SubscribeSuccessEvent{isResubscribed: false, isRecovered: false}

Is this functionality implemented already? I am trying to respond to the subscribing user with some initial user information.

Anyone got an easy way to make the sample app running on my physical Nexus 5x find the localhost:8000 on my laptop over USB ?

I have my nexus 5x being used to test Chat but it of course cant find 127.0.0.1 or localhost to read the server on my laptop.

Got 2 ideas:

1. Use Intlets ( which is like ngrok) and use a public cloud proxy that points all the way down to the local laptop and then the gateway points it to the Server. Thats a bigger project.
2. No idea except some stuff about USB tethering on the internet. Looks like i

See https://centrifugal.github.io/centrifugo/server/server_subs/

My ide gets confused about the types sometimes when I read this library's code. I think this is because there are some mixed relative and absolute imports for internal files: sometimes it is relative and in some other places library files are imported with package:

I suggest that we move all internal imports to relative to avoid namespace confusions and have a better coding experience

I tried to run the chat example on the web but it actually does not want to connect. It just hangs on the connection step, no output

Hi, what would be required in principle to support v3 of the protocol? I would assume and hope that "only" the proto needs to be exchanged and the commands would need to be re-generated, is that roughly right?
Could the client in principle detect the server side version and decide during runtime which command encoder/decoder to use?

The Firebase log record, which is usually seen on Oppo devices, is as follows:

Fatal Exception: io.flutter.plugins.firebase.crashlytics.FlutterError: Bad state: StreamSink is closed
       at _WebSocketImpl.add(_WebSocketImpl.java)
       at DelegatingStreamSink.add(stream_sink.dart:35)
       at _CompleterSink.add(sink_completer.dart:88)
       at WebSocketChannelExtension.sendData(channel.dart:20)
       at Transport.sendAsyncMessage(transport.dart:162)
       at ClientImpl._onPing(client.dart:711)
       at ClientImpl._onPush(client.dart:719)
       at Transport._onData.<fn>.<fn>(transport.dart:266)
       at _GrowableList.forEach(_GrowableList.java)
       at Transport._onData.<fn>(transport.dart:262)

I think it is seen in the application that is pending in the background.

At the moment the demo works :)
I got it working after a few hours. Great stuff and well abstracted.

But i think that we should add an example that is little more data driven so its easier to play around with Centrifuge.

Use this as a basis.
https://github.com/magicwave/mws_mqtt_client
which currently uses: https://github.com/shamblett/mqtt_client
Its for MQTT but is a good example.

It shows the server connected, and allows you to connect.

It allows you to make new channels / topics, so you can play around.

It allows you to test putting data into those channels and see it coming back.

Maybe add login - it does not have it yet.

Then it would be good to add a few examples to really show off how powerful centrifuge can be !

Maybe we should host here ?

I can start on the following below:

1. A Classic Chat app example.

https://github.com/amsokol/flutter-grpc-tutorial

• At the moment it uses GRPC and so i just have to replace that with the centrifuge-dart calls.

2. A real time document collaboration.

https://github.com/memspace/zefyr

• It has a real time update mechanism based on Quill Delta and so we can tap into that. There is golang code so we can add that to the golang examples to work in tandem with the Dart code.
• Will add many user cursors later. Just like you see in Google docs.

3. A Cal App is a good example also

• So peoples cals stay in sync on their many devices.

I am using connecting using a secret token to connect to the sever, but on the server, I am getting the following error

{"level":"info","client":"be291d0f-fafd-4d0e-a201-e518d428b5e3","data":"\ufffd\u0001\b\u0001\u0010\u0000\u001a\ufffd\u0001\n\ufffd\u0001eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpc3MiOiJUZXN0IE9yZ2FuaXNhdGlvbiAxIiwic3ViIjoiNWRhYTAyMzgtN2YwYy0xMWVhLWIxMTItZWFlNTU2OWY4NjAxIiwiZXhwIjoxNTg5OTg3NjYxfQ.fwwM8-L4mqdpK2kFteoYmb6TDfoQ3J0oxiyfCmbIDlY","error":"invalid character 'Õ' looking for beginning of value","user":"","time":"2020-05-19T15:15:30Z","message":"error decoding command"}

The following \ufffd\u0001\b\u0001\u0010\u0000\u001a\ufffd\u0001\n\ufffd\u0001 is being added to the token eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpc3MiOiJUZXN0IE9yZ2FuaXNhdGlvbiAxIiwic3ViIjoiNWRhYTAyMzgtN2YwYy0xMWVhLWIxMTItZWFlNTU2OWY4NjAxIiwiZXhwIjoxNTg5OTg3NjYxfQ.fwwM8-L4mqdpK2kFteoYmb6TDfoQ3J0oxiyfCmbIDlY

This same token works fine for other centrifuge (js, golang, java) clients for the same server.

I have used the example code https://github.com/centrifugal/centrifuge-dart/blob/master/example/console/simple.dart

Hi, I wan get the connInfo and chanInfo from the LeaveEvent and JoinEvent etc, But I cannot simply get it, Help me.
THANKS.

After connecting I am trying to subscribe to a private channel such as $5daa0238-7f0c-11ea-b112-eae5569f8601#5daa0238-7f0c-11ea-b112-eae5569f8601

When I send the subscribe, on the server I am seeing the following in the log

{"level":"info","client":"436bb802-c9a3-471c-99d1-36b94cdf32c3","command":"id:2 method:SUBSCRIBE params:\"\\nJ$5daa0238-7f0c-11ea-b112-eae5569f8601#5daa0238-7f0c-11ea-b112-eae5569f8601\\022\\000\" ","error":"103: permission denied","reply":"id:2 error:<code:103 message:\"permission denied\" > ","user":"5daa0238-7f0c-11ea-b112-eae5569f8601","time":"2020-05-21T15:41:11Z","message":"client command error"}

I am sure this is related to protobuf format, but not sure what to do.
The channel is being recieved as \\nJ$5daa0238-7f0c-11ea-b112-eae5569f8601#5daa0238-7f0c-11ea-b112-eae5569f8601\\022\\000\

I read in the readme for centrifuge-dart, that subscribe to private channels with JWT is supported. So not sure what I am missing. Is there any change required on the server?

@FZambia Sorry was not able to open the old issue.

Here is what I get in my logs after trying to connect to a server (using v0.9.1).

      Null check operator used on a null value
      #0      Transport._onDone.<anonymous closure> (package:centrifuge/src/transport.dart:219:38)
      #1      _rootRun (dart:async/zone.dart:1418:47)
      #2      _CustomZone.run (dart:async/zone.dart:1328:19)
      #3      _CustomZone.runGuarded (dart:async/zone.dart:1236:7)
      #4      _BufferingStreamSubscription._sendDone.sendDone (dart:async/stream_impl.dart:394:13)
      #5      _BufferingStreamSubscription._sendDone (dart:async/stream_impl.dart:404:7)
      #6      _BufferingStreamSubscription._close (dart:async/stream_impl.dart:291:7)
      #7      _SyncStreamControllerDispatch._sendDone (dart:async/stream_controller.dart:782:19)
      #8      _StreamController._closeUnchecked (dart:async/stream_controller.dart:637:7)
      #9      _StreamController.close (dart:async/stream_controller.dart:630:5)
      #10     new _WebSocketImpl._fromSocket.<anonymous closure> (dart:_http/websocket_impl.dart:1156:19)
      #11     _rootRunBinary (dart:async/zone.dart:1450:47)
      #12     _CustomZone.runBinary (dart:async/zone.dart:1342:19)
      #13     _CustomZone.runBinaryGuarded (dart:async/zone.dart:1252:7)
      #14     _BufferingStreamSubscription._sendError.sendError (dart:async/stream_impl.dart:360:15)
      #15     _BufferingStreamSubscription._sendError (dart:async/stream_impl.dart:375:9)
      #16     _BufferingStreamSubscription._addError (dart:async/stream_impl.dart:280:7)
      #17     _SinkTransformerStreamSubscription._addError (dart:async/stream_transformers.dart:75:11)
      #18     _SinkTransformerStreamSubscription._handleData (dart:async/stream_transformers.dart:113:7)
      #19     _rootRunUnary (dart:async/zone.dart:1434:47)
      #20     _CustomZone.runUnary (dart:async/zone.dart:1335:19)
      #21     _CustomZone.runUnaryGuarded (dart:async/zone.dart:1244:7)
      #22     _BufferingStreamSubscription._sendData (dart:async/stream_impl.dart:341:11)
      #23     _BufferingStreamSubscription._add (dart:async/stream_impl.dart:271:7)
      #24     _SyncStreamControllerDispatch._sendData (dart:async/stream_controller.dart:774:19)
      #25     _StreamController._add (dart:async/stream_controller.dart:648:7)
      #26     _StreamController.add (dart:async/stream_controller.dart:596:5)
      #27     _Socket._onData (dart:io-patch/socket_patch.dart:2314:41)
      #28     _rootRunUnary (dart:async/zone.dart:1442:13)
      #29     _CustomZone.runUnary (dart:async/zone.dart:1335:19)
      #30     _CustomZone.runUnaryGuarded (dart:async/zone.dart:1244:7)
      #31     _BufferingStreamSubscription._sendData (dart:async/stream_impl.dart:341:11)
      #32     _BufferingStreamSubscription._add (dart:async/stream_impl.dart:271:7)
      #33     _SyncStreamControllerDispatch._sendData (dart:async/stream_controller.dart:774:19)
      #34     _StreamController._add (dart:async/stream_controller.dart:648:7)
      #35     _StreamController.add (dart:async/stream_controller.dart:596:5)
      #36     new _RawSocket.<anonymous closure> (dart:io-patch/socket_patch.dart:1839:33)
      #37     _NativeSocket.issueReadEvent.issue (dart:io-patch/socket_patch.dart:1322:14)
      #38     _microtaskLoop (dart:async/schedule_microtask.dart:40:21)
      #39     _startMicrotaskLoop (dart:async/schedule_microtask.dart:49:5)

flutter doctor:

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    • macOS (desktop)    • macos                                • darwin-arm64
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[✓] HTTP Host Availability
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• No issues found!

I think Centrifuge.Subscription should have a dispose method to be called when it's removed from Centrifuge.Client to free up resources and close all EvenSink's.

[VERBOSE-2:ui_dart_state.cc(148)] Unhandled Exception: NoSuchMethodError: The method '+' was called on null.

version: 0.2.0

Hi. Trying to learn this library I ended up making a helper class that reduces the api surface and the boilerplate. Commented code and an example are available: https://github.com/synw/centrifuge-dart/tree/connection_manager/example/manager

It looks like this:

final cent = CentrifugoConnectionManager(
      serverUrl: conf.centrifugoUrl, userToken: token)
    ..connect();
  await cent.onConnected;
  final chan = cent.addChannel("chat");
  await chan.subscribe(
      onMessage: (Map<String, dynamic> payload) => print("MSG $payload"));
  await chan.onJoin;
  unawaited(chan.publish(<String, dynamic>{"message": "Foo"}));

This approach is based on callbacks and completers: this way the user does not have to manage half a dozen stream subscriptions. I added a CentrifugoChannel model as a paradigm for the library user

please update the protobuf version

ErrorEvent{error: Connect error: ClientDisconnectedError}

I am getting this error. I think the problem is that I can't assign the token properly. How can I use the setToken command like in JS. Also how can I make 'debug:true' as in the code below.

const centrifuge = new Centrifuge('url', {
websocket: WebSocket,
debug: true
});

Can you upgrade protobuf version?
from protobuf : ^2.0.0 to protobuf: ^3.0.0

https://centrifugal.dev/docs/transports/uni_sse

Would be great if the dart side would support the uni_sse communication as well

Have you any plan with this?

Hello! Sorry, is it possible to upgrade the protobuf package to the latest?

Because centrifuge >=0.2.0 depends on protobuf ^0.13.2 and my_flutter_app depends on protobuf ^1.0.1, centrifuge >=0.2.0 is forbidden.
So, because my_flutter_app depends on centrifuge ^0.4.1, version solving failed.
pub upgrade failed (1; So, because my_flutter_app depends on centrifuge ^0.4.1, version solving failed.)

Thank you in advance for considering the matter.

I can successfully connect to Centrifugo server using JWT and setToken() method. Tested with admin panel and i can only receive message.

Whenever i try to send message i get this Unhandled Exception: Error{code: 103, message: permission denied}

Here is what i am trying

 void sendMessage(SendChatMessage message) async {
    final output = jsonEncode({'token': profileInfo.chatToken, 'data' : {'msg': message.message}});
    final data = utf8.encode(output);
    await _subscriptions[message.channel].publish(data);
  }

I am using version ^0.8.0. I was thinking that

socketSubscription.publishStream.listen((event) {
print(event);
});

with this code I can read the data falling into the socket. Although I do not get any problems in the connection, no data falls into the socket.

EDIT: No problem, I couldn't delete the issue.

return _socket!.close();

https://github.com/centrifugal/centrifuge-dart/blame/53dc5a90a97831faafa5bd60f2c8f3237f6a1b6f/lib/src/transport.dart#L84

#0      Transport.close (package:centrifuge/src/transport.dart:84:19)
#1      ClientImpl.disconnect (package:centrifuge/src/client.dart:207:22)
#2      _CentrifugeConnectMixin.close (package:magistral/src/features/socket_connector/data/centrifuge_connector.dart:167:13)
<asynchronous suspension>

To make cross device testing easier can we change how we set the domain used.

its here at:
https://github.com/centrifugal/centrifuge-dart/blob/master/example/flutter_app/lib/main.dart#L41

Suggest easiest for now is an asset file with a config in it that we read at startup.
Just as here:
https://pub.dartlang.org/packages/global_configuration#pubspec.yaml

Then you can just drop in whichever config you need with the "domain"
For example i am using ngrok to make all devices be able to see the server locally, but also so that i can eavesdrop the connection easily to help debug.

Is this ok with everyone ?

I have crashlog in firebase:
NoSuchMethodError: The method 'close' was called on null. Receiver: null Tried calling: close()
Transport.close (Transport.java:93)
ClientImpl.disconnect (ClientImpl.java:144)
CentrifugeInteractor.dispose (CentrifugeInteractor.java:47)
CartPharmaciesListPageBLoC._stopCentrifuge (CartPharmaciesListPageBLoC.java:289)
CartPharmaciesListPageBLoC.dispose (CartPharmaciesListPageBLoC.java:156)
_CartPharmaciesListPageState.dispose (_CartPharmaciesListPageState.java:94)

Seems, it happen when invoke _transport.close() when _transport not build yet.

please i'd like to know if message recovery mechanism functionality is working with this client. and if not what would it take to get that working?

I have tried dev, beta and master channel and none worked.

I think it might be the way my AVD is configured for android.
Need the right SDK ?
Anyone got an idea ?

x-MacBook-Pro: apple$ flutter doctor 
Doctor summary (to see all details, run flutter doctor -v):
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    ✗ Android license status unknown.
      Try re-installing or updating your Android SDK Manager.
      See https://developer.android.com/studio/#downloads or visit https://flutter.io/setup/#android-setup for detailed instructions.
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x-MacBook-Pro: apple$ flutter build apk
Initializing gradle...                                              3.2s
Resolving dependencies...                                               
* Error running Gradle:
ProcessException: Process "/Users/apple/workspace/go/src/github.com/centrifugal/centrifuge-dart/example/flutter_app/android/gradlew" exited abnormally:

FAILURE: Build failed with an exception.

* Where:
Build file '/Users/apple/workspace/go/src/github.com/centrifugal/centrifuge-dart/example/flutter_app/android/build.gradle' line: 24

* What went wrong:
A problem occurred evaluating root project 'android'.
> A problem occurred configuring project ':app'.
   > No toolchains found in the NDK toolchains folder for ABI with prefix: mips64el-linux-android

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.

* Get more help at https://help.gradle.org

BUILD FAILED in 1s
  Command: /Users/apple/workspace/go/src/github.com/centrifugal/centrifuge-dart/example/flutter_app/android/gradlew app:properties


Please review your Gradle project setup in the android/ folder.

I tried connecting to a remote centrifugo deployment using the code above and got the error below,

I want to add that this is the version of the dart package I'm using centrifuge: ^0.9.2 and the version of the remote deployment is 4.1.2

I've installed centrifuge lib in my flutter app. Not the version from pub, but directly from my fork of main repo. Suddenly I've experienced a bug: app crashes after recovering internet connection. There were no error messages in console, only 'Lost connection to device'.

Steps to reproduce (on iOS simulator):

1. With active internet connection, connect to centrifuge on app start
2. Subscribe to some arbitrary channel
3. Disconnect from internet for about 30-40 seconds
4. Enable internet again

After doing that, app crashes after a couple of sesonds.
Tried launching app through Xcode, but when app crashes, there are also no error logs, only Message from debugger: Terminated due to signal 13.

flutter doctor:

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• No issues found!

Hello. I'm trying to use a centrifuge to create a simple chat and can't think of a better way to handle connection errors (for example, the user has no internet or the server is not available). Is there any way to do this?

import 'dart:async';
import 'dart:convert';
import 'package:centrifuge/centrifuge.dart' as centrifuge;
import 'package:flutter/material.dart';
import 'package:mize/constants/api_endpoints.dart';
import 'package:mize/models/notification_model.dart';
import 'package:fluttertoast/fluttertoast.dart';
import 'dart:developer' as dev;

class NotificationClient {
late centrifuge.Client _centrifuge;
centrifuge.Subscription? _subscription;
StreamSubscription<centrifuge.ConnectedEvent>? _connectedSub;
StreamSubscription<centrifuge.ConnectingEvent>? _connectingSub;
StreamSubscription<centrifuge.DisconnectedEvent>? _disconnectedSub;
StreamSubscription<centrifuge.ErrorEvent>? _errorSub;

final services = StreamController();

Stream get notifications => services.stream;

// void init() {
// debugPrint('connected');
// const url = ApiEndpoints.websocketurl;
// _centrifuge = centrifuge.createClient(
// url,
// centrifuge.ClientConfig(
// token: ApiEndpoints.centrifugoToken,
// ));
// _centrifuge.connect();
// _subscription?.subscribe();
// }

NotificationClient() {
// debugPrint('connected');
const url = ApiEndpoints.websocketurl;
_centrifuge = centrifuge.createClient(
url,
centrifuge.ClientConfig(
token: ApiEndpoints.centrifugoToken,

    ));
// _centrifuge.connect();
// _subscription?.subscribe();

}
Future connect() async {
_centrifuge.connected.listen((event) {
// onConnect();
Fluttertoast.showToast(
msg: "Connected to Centrifugo server",
backgroundColor: Colors.green,
textColor: Colors.white);
});
_centrifuge.connecting.listen((event) {
// onConnect();
Fluttertoast.showToast(
msg: "Connecting to Centrifugo server",
backgroundColor: Colors.green,
textColor: Colors.white);
});
_centrifuge.disconnected.listen((event) {
Fluttertoast.showToast(
msg: "Centrifugo server disconnected",
backgroundColor: Colors.red,
textColor: Colors.white);
});
_centrifuge.error.listen((event) {
Fluttertoast.showToast(
msg: 'error', backgroundColor: Colors.red, textColor: Colors.white);
print(event);
});
await _centrifuge.connect();
}

Future subscribe(String channel) async {
_subscription = _centrifuge.getSubscription(channel)!;
_subscription?.publication.listen((event) {
final data = utf8.decode(event.data);
final notification = json.decode(data);
final body = notification['body'].toString();
final message = notification['message'].toString();
services.sink.add(NotificationModel(body: body, message: message));
});
_subscription?.subscribing.listen((event) {
Fluttertoast.showToast(
msg: "Subscribing to Centrifugo server",
backgroundColor: Colors.green,
textColor: Colors.white);
});
_subscription?.subscribed.listen((event) {
Fluttertoast.showToast(
msg: "Subscribed to Centrifugo server",
backgroundColor: Colors.green,
textColor: Colors.white);
});
_subscription?.unsubscribed.listen((event) {
Fluttertoast.showToast(
msg: "unsubscribing to Centrifugo server",
backgroundColor: Colors.green,
textColor: Colors.white);
});

await _subscription?.subscribe();

}

Future dispose() async {
await _connectedSub?.cancel();
await _connectingSub?.cancel();
await _disconnectedSub?.cancel();
await _errorSub?.cancel();
}

void listenToNotifications(NotificationModel noti) async {
final output = jsonEncode({'body': noti.body, 'message': noti.message});
print('Sending msg : $output');
final data = utf8.encode(output);
try {
await _subscription?.publish(data);
} on Exception {
rethrow;
}
}
}