apps/notifications/consumers.py

import json
from channels.generic.websocket import AsyncWebsocketConsumer
from channels.db import database_sync_to_async

class NotificationConsumer(AsyncWebsocketConsumer):
    async def connect(self):
        self.user = self.scope["user"]
        
        if not self.user.is_authenticated:
            await self.close()
            return

        self.group_name = f"user_{self.user.id}"

        # Join user group
        await self.channel_layer.group_add(
            self.group_name,
            self.channel_name
        )

        await self.accept()

    async def disconnect(self, close_code):
        if hasattr(self, 'group_name'):
            # Leave user group
            await self.channel_layer.group_discard(
                self.group_name,
                self.channel_name
            )

    # Receive message from user group
    async def notification_message(self, event):
        # Send message to WebSocket
        await self.send(text_data=json.dumps({
            'type': 'notification',
            'notification': event['notification']
        }))