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Cannot access scope["user"] object from an async consumer

See original GitHub issue

Traceback:

2018-04-13 17:44:51,382 - ERROR - server - Exception inside application: You cannot use AsyncToSync in the same thread as an async event loop - just await the async function directly.
  File "/tmp/channels-examples/multichat/channels/consumer.py", line 54, in __call__
    await await_many_dispatch([receive, self.channel_receive], self.dispatch)
  File "/tmp/channels-examples/multichat/channels/utils.py", line 50, in await_many_dispatch
    await dispatch(result)
  File "/tmp/channels-examples/multichat/channels/consumer.py", line 67, in dispatch
    await handler(message)
  File "/tmp/channels-examples/multichat/channels/generic/websocket.py", line 173, in websocket_connect
    await self.connect()
  File "/tmp/channels-examples/multichat/chat/consumers.py", line 26, in connect
    if self.scope["user"].is_anonymous:
  File "/tmp/channels-examples/multichat/env/lib/python3.6/site-packages/django/utils/functional.py", line 215, in inner
    self._setup()
  File "/tmp/channels-examples/multichat/env/lib/python3.6/site-packages/django/utils/functional.py", line 349, in _setup
    self._wrapped = self._setupfunc()
  File "/tmp/channels-examples/multichat/channels/auth.py", line 142, in <lambda>
    scope["user"] = SimpleLazyObject(lambda: async_to_sync(get_user)(scope))
  File "/tmp/channels-examples/multichat/env/lib/python3.6/site-packages/asgiref/sync.py", line 34, in __call__
    "You cannot use AsyncToSync in the same thread as an async event loop - "
  You cannot use AsyncToSync in the same thread as an async event loop - just await the async function directly.

Using AuthMiddleware: accessing the scope[“user”] object from an asynchronous consumer triggers this error.

This happens since #923 was merged (published in Channels v2.1.0). The traceback can be reproduced with the following steps:

clone andrewgodwin/channels-example and install dependencies.
create a superuser
create a chatroom on the admin site
try to connect to that chatroom

Issue Analytics

State:
Created 5 years ago
Comments:15 (5 by maintainers)

Top GitHub Comments

5reactions

andrewgodwincommented, Apr 18, 2018

OK this is released in channels 2.1.1.

4reactions

andrewgodwincommented, Apr 13, 2018

Just confirming that this is an error caused by the release of Channels 2.1, but it’s also correct to complain. I am investigating possible fixes now.

In the meantime, if this is happening in your own code, you can replace scope["user"] with await channels.auth.get_user(scope)

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