Problem with UUID inside url route in async testing

[Massakera]

I've built a simple chatroom and now I want to code a test to verify if Its connecting. Following the tutorial in Channels docs i come up with the following test:

class ViewTestCase(TestCase):
@classmethod
def setUp(self):
    user_moderator = User.objects.create_superuser(first_name='tester',
        username='test1', 
        password='123', 
        email='[email protected]')

    user_player = User.objects.create_user(first_name='player',
    username='player1',
    password='1234',
    email='[email protected]')

    pack1 = Pack.objects.create(deckStyle='Fibonacci',deck=['1','2','3'])

    self.room = PokerRoom.objects.create(status='Pending',name='planning',styleCards='Fibonacci',
    user=User.objects.get(username='test1'),
    deck=Pack.objects.get(deckStyle='Fibonacci'),index=1)
    
    user_player = ParticipatingUser.objects.create(name='player',idRoom=PokerRoom.objects.get(name='planning'), status='Pending')

    self.story = Story.objects.create(storyName='testplanning',
    idRoom=PokerRoom.objects.get(name='planning'),
    status='Pending')



    
async def test_consumer(self):
    
    application = URLRouter([
        url(r'ws/chat/(?P<room_name>[A-Za-z0-9_-]+)/participant/(?P<user>\w+)/$', consumers.ChatConsumer.as_asgi()),
    ])
    communicator = WebsocketCommunicator(application,"/ws/chat/room_id/participant/participant_id)/")
    connected, subprotocol = await communicator.connect()
    assert connected    
    await communicator.disconnect()

My problem is that I need to substitute room_id and participant_id inside my WebsocketCommunicator. participant_id is just an commom id and my room_id is a UUIDField. I've been using the following method to extract these ids in my others tests:

      def test_something(self):
        room_id = PokerRoom.objects.get(name='planning').id
        user_id = User.objects.get(username='tester').id
        ...

But if I use the same method inside async def like this:

async def test_something(self):
        room_id = PokerRoom.objects.get(name='planning').id
        user_id = User.objects.get(username='tester').id
        ...

I get this error django.core.exceptions.SynchronousOnlyOperation: You cannot call this from an async context - use a thread or sync_to_async.

How can I solve this?

[carltongibson]

You need to use sync_to_async() ... See the Database access section of the docs.

[Massakera]

Trying to use as suggested:

async def test_consumer(self):
    room_id = await database_sync_to_async(self.get_room_id)()
    user_id = await database_sync_to_async(self.get_user_id)()
    application = URLRouter([
        url(r'ws/chat/(?P<room_name>[A-Za-z0-9_-]+)/participant/(?P<user>\w+)/$', consumers.ChatConsumer.as_asgi()),
    ])
    communicator = WebsocketCommunicator(application,f'/ws/chat/{room_id}/participant/{user_id})/')
    connected, subprotocol = await communicator.connect()
    assert connected    
    
def get_room_id(self):
    return PokerRoom.objects.get(name='planning').id

def get_user_id(self):
    return ParticipatingUser.objects.get(name='player').id

But now is throwing an error: psycopg2.InterfaceError: connection already closed

[carltongibson]

There’s not really enough to see what’s going on here but try with just sync_to_async, rather than the database_ version.

[Massakera]

Thanks! Now it's working