One or more namespaces failed to connect

[emanuele3d]

Hi everybody,

I'm writing integration tests and I am trying to connect to the server being tested with the following code:

    class TestClient:
        def __init__(self, address, topic):

            self.receivedData = None
            self._address = address
            self._topic = topic

            self._client = socketio.AsyncClient(logger=True,
                                                engineio_logger=True)
            self._client.on('TopicData',
                            handler=self._handle_topic_data,
                            namespace=topic)

        async def startup(self):

            headers = dict(type='TestNode', id='TestNode-1')
            print('Connecting to %s, topic %s' %
                  (self._address, self._topic))
            await self._client.connect(self._address, headers,
                                       namespaces=self._topic)
            print('Connected')
            await self._client.sleep(5)

        async def _handle_topic_data(self, data):
            self.receivedData = data
            #self._client.disconnect()

    testClient = TestClient('http://127.0.0.1:%d' % self._testNodePort,
                            topic='TEST')

    asyncio.get_event_loop().run_until_complete(testClient.startup())

Server side I get this log:

        Server initialized for aiohttp.
======== Running on http://0.0.0.0:9302 ========
(Press CTRL+C to quit)
9d00EuqDFYrcI3SkAAAA: Sending packet OPEN data {'sid': '9d00EuqDFYrcI3SkAAAA', 'upgrades': ['websocket'], 'pingTimeout': 20000, 'pingInterval': 25000}
9d00EuqDFYrcI3SkAAAA: Received request to upgrade to websocket
9d00EuqDFYrcI3SkAAAA: Upgrade to websocket successful
9d00EuqDFYrcI3SkAAAA: Received packet MESSAGE data 0TEST,
message async handler error
Traceback (most recent call last):
  File "D:\dev\gitrepos\tests\venv\lib\site-packages\engineio\asyncio_server.py", line 447, in _trigger_event
    ret = await self.handlers[event](*args)
  File "D:\dev\gitrepos\tests\venv\lib\site-packages\socketio\asyncio_server.py", line 563, in _handle_eio_message
    pkt = packet.Packet(encoded_packet=data)
  File "D:\dev\gitrepos\tests\venv\lib\site-packages\socketio\packet.py", line 40, in __init__
    self.attachment_count = self.decode(encoded_packet)
  File "D:\dev\gitrepos\tests\venv\lib\site-packages\socketio\packet.py", line 111, in decode
    self.data = self.json.loads(ep)
  File "D:\dev\gitrepos\tests\venv\lib\site-packages\engineio\json.py", line 16, in loads
    return original_loads(*args, **kwargs)
  File "C:\Program Files\Python38\lib\json\__init__.py", line 370, in loads
    return cls(**kw).decode(s)
  File "C:\Program Files\Python38\lib\json\decoder.py", line 337, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())
  File "C:\Program Files\Python38\lib\json\decoder.py", line 355, in raw_decode
    raise JSONDecodeError("Expecting value", s, err.value) from None
json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0)
YbcKt7By7-MK3PIZAAAB: Sending packet OPEN data {'sid': 'YbcKt7By7-MK3PIZAAAB', 'upgrades': ['websocket'], 'pingTimeout': 20000, 'pingInterval': 25000}
YbcKt7By7-MK3PIZAAAB: Received request to upgrade to websocket
YbcKt7By7-MK3PIZAAAB: Upgrade to websocket successful
YbcKt7By7-MK3PIZAAAB: Received packet MESSAGE data 0
YbcKt7By7-MK3PIZAAAB: Sending packet MESSAGE data 0{"sid":"MpCZdf6p8Ye6JkvBAAAC"}
YbcKt7By7-MK3PIZAAAB: Received packet MESSAGE data 2["ShutdownCommand",{}]
received event "ShutdownCommand" from MpCZdf6p8Ye6JkvBAAAC [/]

As you can see the server and the client do talk to each other briefly, but then something goes wrong. On the server there is a handler correctly registered for the 'connect' event in the TEST namespace (it doesn't get executed at all), and in general very similar code has worked fine in other circumstances, so I am a little bit stumped at what might be causing this and the JSON-related error is quite mysterious to me. Do you have tips and tricks to share on how to debug this?

[miguelgrinberg]

Namespaces must begin with a slash. Use /TEST.

[emanuele3d]

My saviour!!! Man I banged my head on this for the past three days. It makes sense but I completely forgot about it.

In my defence the server documentation page which I was primarily looking at does not include the sentence "Namespaces use a path syntax starting with a forward slash." Only the documentation page for the client does, but I missed it.

Nevertheless, thank you very much. I was really confused as to why a different microservice with very similar code worked flawlessly and this one didn't.

[Satyamcoretus]

@miguelgrinberg
please make me understand this issue also ,
this is my server side code -

import socketio
import uuid


sio = socketio.AsyncServer(cors_allowed_origins='*',async_mode='asgi')
app = socketio.ASGIApp(sio)


rooms = {}  # Dictionary to store room information (clients in each room)

@sio.event
async def connect(sid):
    print(f'Client {sid} connected')

@sio.event
async def create_room(sid):
    room_id = str(uuid.uuid4())  # Generate a unique room ID
    rooms[room_id] = {sid}  # Add the connecting client to the room
    await sio.emit(event='room_created', data={'room_id': room_id}, to=sid)
    print(f'Client {sid} created room: {room_id}')

@sio.event
async def join_room(sid, room_id):
    if room_id in rooms:
        rooms[room_id].add(sid)  # Add client to the room
        # enter into the room
        await sio.enter_room(sid=sid,room=room_id)
        print(f'User [{sid}] entered the room - [{room_id}] ')

        await sio.emit(event='room_joined', data={'room_id': room_id}, to=sid)
        print(f'Client {sid} joined room: {room_id}')
        # Broadcast a message to existing clients in the room

    else:
        await sio.emit(event='room_error', data={'message': 'Room does not exist'}, to=sid)
        print(f'Client {sid} attempted to join non-existent room: {room_id}')

@sio.event
async def chat_message(sid, room_id, data):
    if room_id in rooms and sid in rooms[room_id]:
        # Broadcast the message to all clients in the room except the sender
        await sio.emit(event='message', data=data, room=room_id, skip_sid=sid)
        print(f'Client {sid} sent message in room {room_id}: {data}')
    else:
        await sio.emit(event='chat_error', data={'message': 'You are not in this room'}, to=sid)
        print(f'Client {sid} attempted to send message in non-existent room: {room_id}')

@sio.event
async def disconnect(sid):
    # Remove the client from any rooms they were in
    for room_id, clients in rooms.items():
        if sid in clients:
            clients.remove(sid)
            if not clients:  # If the room becomes empty, remove it
                del rooms[room_id]
            # Notify remaining clients in the room about the disconnection
            await sio.emit(event='user_left', data={'message': f'{sid} has left the room'}, room=room_id)
            print(f'Client {sid} disconnected from room: {room_id}')

if __name__ == '__main__':
    import uvicorn
    uvicorn.run(app, host='192.168.0.53', port=8000)

this is client side code -

import asyncio
import socketio

loop = asyncio.get_event_loop()
sio = socketio.AsyncClient()


room_id = None  # Store the current room ID


async def initiator():              # It will send the first ping to the server
    #emit to the server, it will generate a new room key for the client
    await sio.emit(event='create_room')


@sio.event
async def connect():
    print('Connection established')
    await initiator()


@sio.event
async def room_created(data):
    global room_id
    room_id = data['room_id']
    print(f'Room created: {room_id}')
#
@sio.event
async def room_joined(data):
    global room_id
    room_id = data['room_id']
    print(f'Joined room: {room_id}')

@sio.event
async def room_error(data):
    print(f'Error: {data["message"]}')
async def main():
    await sio.connect('http://192.168.0.53:8000')
    await sio.wait()



if __name__ == '__main__':
    loop.run_until_complete(main())

and this exception has been raising again and again -

Traceback (most recent call last):
File "/home/coretus-15/Satyam/socketio_new_agent/room_client.py", line 63, in
loop.run_until_complete(main())
File "/usr/lib/python3.10/asyncio/base_events.py", line 649, in run_until_complete
return future.result()
File "/home/coretus-15/Satyam/socketio_new_agent/room_client.py", line 57, in main
await sio.connect('http://192.168.0.53:8000')
File "/home/coretus-15/Satyam/socket_io_next/venv/lib/python3.10/site-packages/socketio/async_client.py", line 170, in connect
raise exceptions.ConnectionError(
socketio.exceptions.ConnectionError: One or more namespaces failed to connect

server side error -

message async handler error
Traceback (most recent call last):
File "/home/coretus-15/Satyam/socket_io_next/venv/lib/python3.10/site-packages/socketio/async_server.py", line 552, in _handle_connect
success = await self._trigger_event(
File "/home/coretus-15/Satyam/socket_io_next/venv/lib/python3.10/site-packages/socketio/async_server.py", line 634, in _trigger_event
ret = await handler(*args)
TypeError: connect() takes 1 positional argument but 2 were given

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/home/coretus-15/Satyam/socket_io_next/venv/lib/python3.10/site-packages/engineio/async_server.py", line 483, in run_async_handler
return await self.handlersevent
File "/home/coretus-15/Satyam/socket_io_next/venv/lib/python3.10/site-packages/socketio/async_server.py", line 669, in _handle_eio_message
await self._handle_connect(eio_sid, pkt.namespace, pkt.data)
File "/home/coretus-15/Satyam/socket_io_next/venv/lib/python3.10/site-packages/socketio/async_server.py", line 555, in _handle_connect
success = await self._trigger_event(
File "/home/coretus-15/Satyam/socket_io_next/venv/lib/python3.10/site-packages/socketio/async_server.py", line 634, in _trigger_event
ret = await handler(*args)
TypeError: connect() takes 1 positional argument but 3 were given

how to get the information of all the namespaces running under the hood. I just want to run this on the default namespaces which is '/'.

when set logger = True in AsyncClint() class then I got these additional info
socketio.exceptions.ConnectionError: One or more namespaces failed to connect
(venv) coretus-15@coretus-15:~/Satyam/socketio_new_agent$ python room_client.py
Attempting WebSocket connection to ws://localhost:8000/socket.io/?transport=websocket&EIO=4
WebSocket connection accepted with {'sid': 'OjDtd3T1mG6aKIhZAAAI', 'upgrades': [], 'pingTimeout': 20000, 'pingInterval': 25000}
Engine.IO connection established
Sending packet MESSAGE data 0{}
Sending packet CLOSE data None
Engine.IO connection dropped
Write loop: WebSocket connection was closed, aborting
Exiting write loop task
Server sent close packet data None, aborting
Waiting for write loop task to end
Exiting read loop task