Django-Channels: How to get channel_name from user_id?

Question

Below code prints the channel_name of a client

class ChatConsumer(WebsocketConsumer):
    def connect(self):
        self.room_name = self.scope['url_route']['kwargs']['room_name']
        self.room_group_name = 'chat_%s' % self.room_name
        print(self.channel_name)

How to get the channel_name from user_id (user.id) for an authenticated user (It needs to be accessed outside the consumer)? Something like below

import foo
channel_name=foo.get_channel_name_from_user_id(user_id)
print(channel_name)

Thanks! Happy new year!

Answer 1

The self.channel_name is not associated to the user-class but to "AsyncWebsocketConsumer";
If you want you can totally specify the channel_name based on the user_id by explicitly defining the channel-layer name as such

async def connect(self):
    user = self.scope['user']

    if user.is_anonymous:
        print("user was unknown")
        await self.close()
    else:
        await self.channel_layer.group_add(
            group=self.doc_pat_grp_id,
            channel=user.id#the channel-name
        )
        await self.accept()

Using Channel-layer outside of consumer

#The python code; like you mentioned above.
import foo
from django.contrib.auth import get_user_model
from channels.layers import get_channel_layer
from asgiref.sync import async_to_sync 
#since django runs synchronously and channel_layer runs asynchronous 
#we need to explicitly tell channel_layer to run it in synchronous

user = get_user_model()
channel_layer = get_channel_layer()
print(channel_layer)