How can I utilize broadcaster to subscribe multiple channel?

[vaibhavmule]

I know a way to have a dynamic channel by having chatroom id in URL, /ws/{chat_id}

I want to send {'type': 'subscribe', 'chat_id': 'dsfjkhdskjfhdskjhfkjdsahfa'}

@app.websocket("/ws")
async def ws_manager(websocket: WebSocket):
    await websocket.accept()
    async for message in websocket.iter_json():
        if message['type'] == 'subscribe':
             chat_id = message['chat_id']
             async with broadcast.subscribe(channel=chat_id) as subscriber:
                   async for event in subscriber:
                       await websocket.send_text(event.message)

how can i have multiple subscriber for same socket connection?

[vaibhavmule]

@tomchristie

[tomchristie]

I'm sorry but I don't really have the time to get into discussions on this particular project at the moment.

[vaibhavmule]

oh okay, anyone else can help with this? cc @rafalp @hramezani

[rafalp]

I don't know - I'm not using broadcaster outside of GraphQL subscriptions.

When I was implementing chat to learn those, I've had single channel named chat and I've included room attribute on chat messages, eg "room": "all" sent message on public chat, "room": "@bob" sent message to single user.

[lewazo]

I simply added a third handler like so

@router.websocket("/ws")
async def websocket_endpoint(websocket: WebSocket):
    await websocket.accept()

    await run_until_first_complete(
        (ws_receiver, {"ws": websocket}),
        (ws_subscribe_all, {"ws": websocket}),
        (ws_subscribe_private, {"ws": websocket, "user_profile_id": user_profile.id}),
    )
    
async def ws_receiver(ws: WebSocket):
    async for message in ws.iter_text():
        # Handle message here
        pass
    
async def ws_subscribe_private(ws: WebSocket, user_profile_id: int):
    private_channel = f"{WS_CHANNEL_PRIVATE_KEY}:{user_profile_id}"

    async with broadcast.subscribe(channel=private_channel) as subscriber:
        async for event in subscriber:
            await ws.send_text(event.message)


async def ws_subscribe_all(ws: WebSocket):
    async with broadcast.subscribe(channel=WS_CHANNEL_ALL_KEY) as subscriber:
        async for event in subscriber:
            await ws.send_text(event.message)

Of course this won't scale if you have a high number of channels, but for a broadcast and private channels, this works great.

[Graeme22]

This definitely seems like something that should be more straightforward.