django项目中服务端实现websocket长连接 主动实时推送消息给客户端

Question

初学python，在django项目中使用channels
通过websocket长连接代替轮询，后端与前端建立连接后 在第三方调用接口生成数据后实时推送给前端
请问在websocketConsumer类怎么拿到对应的各个长连接？
如何在服务端主动实时给客户端推送消息？
谢谢！

Answer 1

类似这种的，通过group_send或者send,直接发送数据

class MessageNotify(AsyncJsonWebsocketConsumer):
    def __init__(self, *args, **kwargs):
        super().__init__(args, kwargs)
        self.room_group_name = None
        self.disconnected = True
        self.username = ""

    async def connect(self):
        status, user_obj = await token_auth(self.scope)
        if not status:
            logger.error(f"auth failed {user_obj}")
            # https://developer.mozilla.org/zh-CN/docs/Web/API/CloseEvent#status_codes
            await self.close(4401)
        else:
            logger.info(f"{user_obj} connect success")
            room_name = self.scope["url_route"]["kwargs"].get('room_name')
            username = self.scope["url_route"]["kwargs"].get('username')
            # data = verify_token(token, room_name, success_once=True)
            if username and room_name:
                self.disconnected = False
                self.username = username
                self.room_group_name = f"message_{room_name}"
                # Join room group
                await self.channel_layer.group_add(self.room_group_name, self.channel_name)
                await self.accept()
            else:
                logger.error(f"room_name:{room_name} token:{username} auth failed")
                await self.close()

    async def disconnect(self, close_code):
        self.disconnected = True
        if self.room_group_name:
            await self.channel_layer.group_discard(self.room_group_name, self.channel_name)

    # Receive message from WebSocket
    async def receive_json(self, content, **kwargs):
        action = content.get('action')
        if not action:
            await self.close()
        data = content.get('data', {})
        if action == "message":
            data['uid'] = self.channel_name
            data['username'] = self.username
            # Send message to room group
            await self.channel_layer.group_send(
                self.room_group_name, {"type": "chat_message", "data": data}
            )
        else:
            await self.channel_layer.send(self.channel_name, {"type": action, "data": data})

    async def userinfo(self, event):
        data = {
            'username': self.username,
            'uid': self.channel_name
        }
        await self.send_data('userinfo', {'data': data})

    async def chat_message(self, event):
        data = event["data"]
        data['time'] = datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S.%f')
        # Send message to WebSocket
        await self.send_data('message', {'data': data})

    async def send_data(self, action, content, close=False):
        data = {
            'time': time.time(),
            'action': action
        }
        data.update(content)
        return await super().send_json(data, close)