custom auth django channels

Step 1: Install Django Channels

pip install channels

Step 2: Create a new Django Channels project

django-admin startproject myproject
cd myproject

Step 3: Install Channels Redis for handling WebSocket connections

pip install channels_redis

Step 4: Update Django settings to use Channels and Channels Redis

# myproject/settings.py

INSTALLED_APPS = [
    # ...
    'channels',
]

# Use Channels as the default ASGI application
ASGI_APPLICATION = 'myproject.asgi.application'

# Configure Channels layer to use Redis as a backing store
CHANNEL_LAYERS = {
    'default': {
        'BACKEND': 'channels_redis.core.RedisChannelLayer',
        'CONFIG': {
            "hosts": [('127.0.0.1', 6379)],
        },
    },
}

Step 5: Create a custom authentication backend

# myproject/authentication.py

from django.contrib.auth.backends import BaseBackend
from django.contrib.auth.models import User

class CustomAuthBackend(BaseBackend):
    def authenticate(self, request, username=None, password=None, kwargs):
        # Your custom authentication logic here
        user = User.objects.get(username=username)
        if user.check_password(password):
            return user
        return None

    def get_user(self, user_id):
        try:
            return User.objects.get(pk=user_id)
        except User.DoesNotExist:
            return None

Step 6: Update Django settings to use the custom authentication backend

# myproject/settings.py

AUTHENTICATION_BACKENDS = [
    # ...
    'myproject.authentication.CustomAuthBackend',
]

Step 7: Implement authentication in Django Channels consumers

# myapp/consumers.py

from channels.generic.websocket import AsyncWebsocketConsumer
from channels.db import database_sync_to_async
from django.contrib.auth import get_user_model

class CustomAuthConsumer(AsyncWebsocketConsumer):
    async def connect(self):
        # Authenticate user using the custom backend
        user = await self.get_user(self.scope['user'])
        if user.is_authenticated:
            # Accept the WebSocket connection
            await self.accept()
        else:
            # Reject the connection
            await self.close()

    @database_sync_to_async
    def get_user(self, user_id):
        User = get_user_model()
        try:
            return User.objects.get(pk=user_id)
        except User.DoesNotExist:
            return None

Step 8: Update routing to use the custom consumer

# myproject/routing.py

from channels.routing import ProtocolTypeRouter, URLRouter
from channels.auth import AuthMiddlewareStack
from myapp.consumers import CustomAuthConsumer

application = ProtocolTypeRouter({
    'websocket': AuthMiddlewareStack(
        URLRouter(
            [
                # Add your WebSocket consumers here
                path('ws/some_path/', CustomAuthConsumer.as_asgi()),
            ]
        )
    ),
})

Step 9: Include the routing configuration in the Django project

# myproject/asgi.py

import os
from django.core.asgi import get_asgi_application
from channels.routing import ProtocolTypeRouter, URLRouter
from myproject.routing import application

os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'myproject.settings')
django_asgi_app = get_asgi_application()

application = ProtocolTypeRouter({
    "http": django_asgi_app,
    "websocket": application,
})

Step 10: Run the Channels development server

daphne myproject.asgi:application