How do you authenticate a websocket with token authentication on django channels?

We want to use django-channels for our websockets but we need to authenticate as well. We have a rest api running with django-rest-framework and there we use tokens to authenticate a user, but the same functionality does not seem to be built into django-channels.

If you are using Django Channels 3 you can use this code: https://gist.github.com/AliRn76/1fb99688315bedb2bf32fc4af0e50157

middleware.py

from django.contrib.auth.models import AnonymousUser
from rest_framework.authtoken.models import Token
from channels.db import database_sync_to_async
from channels.middleware import BaseMiddleware

@database_sync_to_async
def get_user(token_key):
    try:
        token = Token.objects.get(key=token_key)
        return token.user
    except Token.DoesNotExist:
        return AnonymousUser()

class TokenAuthMiddleware(BaseMiddleware):
    def __init__(self, inner):
        super().__init__(inner)

    async def __call__(self, scope, receive, send):
        try:
            token_key = (dict((x.split('=') for x in scope['query_string'].decode().split("&")))).get('token', None)
        except ValueError:
            token_key = None
        scope['user'] = AnonymousUser() if token_key is None else await get_user(token_key)
        return await super().__call__(scope, receive, send)

routing.py

from channels.security.websocket import AllowedHostsOriginValidator
from channels.routing import ProtocolTypeRouter, URLRouter
from .middleware import TokenAuthMiddleware
from main.consumers import MainConsumer
from django.conf.urls import url

application = ProtocolTypeRouter({
        'websocket': AllowedHostsOriginValidator(
            TokenAuthMiddleware(
                URLRouter(
                    [
                        url(r"^main/$", MainConsumer.as_asgi()),
                    ]
                )
            )
        )
    })