Duplicate websocket messages

• Your OS and runtime environment, and browser if applicable

Browser: chrome, OS: ubuntu

• The versions of Channels, Daphne, Django, Twisted, and your ASGI backend (asgi_ipc or asgi_redis normally)

asgi-redis==1.4.3 channels==1.1.8 Django==1.10.4 Twisted==16.6.0

• What you expected to happen vs. what actually happened

I am receiving duplicate messages in my consumer. I have a java client that stays connected and attempts to reconnect at all times to the websocket. I also have web clients sending messages to websocket to a dedicated channels group just for them, which is then resent to a dedicated channels group for the java process. Especially if I restart daphne, runworker and celery a lot, I receive duplicate messages (or triplicate, or nplicate, you get the idea) from my web clients. I have verified that the messages are not sent twice by the clients. Note that I’ve logged the duplicate messages in python (def ws_message(message)), not just in my java process, which consequently also receives duplicates. Once I start to receive duplicates I have to restart the processes, and then it’s ok until I restart it again. It seems rather random, the fact if I do or do not get duplicates within a lifecycle of the channels app, but the issue is never resolved without a restart. I receive n-plicates from all my clients, which are many.

• How you’re running Channels (runserver? daphne/runworker? Nginx/Apache in front?)

I’m running it behind nginx with daphne & runworker.

• Console logs and full tracebacks of any errors

No errors really, just duplicates.

This is how I’m logging my duplicates:

channel_routing = [
    route("websocket.connect", ws_add),
    route("websocket.receive", ws_message),
    route("websocket.disconnect", ws_disconnect),
]

def ws_add(message):
    room = re.sub("/websocket/", '', message.content['path'])
    message.reply_channel.send({"accept": True})
    Group(str(room)).add(message.reply_channel)

def ws_message(message):
    room = re.sub("/websocket/", '', message.content['path'])
    text = message.content['text']
    txt = json.loads(text)
    print(txt)

def ws_disconnect(message):
    Group("java").discard(message.reply_channel)
    Group("web").discard(message.reply_channel)

I am using reconnecting-websocket (https://github.com/joewalnes/reconnecting-websocket) to connect to it via frontend.

[andrewgodwin]

Channels 2 is released, closing this as the transport is now not over a network and so this won’t happen.

[andrewgodwin]

@bkovacev Hard deadlines are not something a volunteer project has, but it should be more like 2 months than 6.