首页 > 解决方案 > Django Channels:应用程序内部异常:消息类型app_consumer.notification_message没有处理程序

问题描述

我正在尝试在特定事件上使用 websockets 向用户发送通知。我有以下触发 websocket 方法的模型接收器:

@receiver(pre_save, sender=settings.AUTH_USER_MODEL)
def create_auth_token(sender, instance=None, created=False, update_fields=None, **kwargs):
    if update_fields:
        if 'pan_number_verified' in update_fields and instance.pan_number_verified is True:
            notification = Notification.objects.create(message='Your PAN Number has been verified...Head on to '
                                                               'creating a campaign right away.', user=instance)
            channel_layer = get_channel_layer()
            async_to_sync(channel_layer.group_send)("notification_%s" % instance.id, {
                "type": "app_consumer.notification_message",
                "message": str(notification.id)
            })

这是我的应用消费者:

class AppConsumer(WebsocketConsumer):
    def connect(self):
        self.room_name = self.scope['url_route']['kwargs']['user_id']
        self.room_group_name = 'notification_%s' % self.room_name
        async_to_sync(self.channel_layer.group_add)(
            self.room_group_name,
            self.channel_name
        )
        self.accept()

    def disconnect(self, close_code):
        async_to_sync(self.channel_layer.group_discard)(
            self.room_group_name,
            self.channel_name
        )

    def receive(self, text_data):
        text_data_json = json.loads(text_data)
        message = text_data_json['message']

        async_to_sync(self.channel_layer.group_send)(
            self.room_group_name,
            {
                'type': 'app_consumer.notification_message',
                'message': message
            }
        )

    def notification_message(self, event):
        message = event['message']

        self.send(text_data=json.dumps({
            'message': message
        }))

但我收到以下错误消息:

应用程序内部异常:没有消息类型 app_consumer.notification_message 的处理程序

文件“/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/channels/consumer.py”,第 59 行,调用 [receive,self.channel_receive],self.dispatch

文件“/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/channels/utils.py”,第 51 行,在 await_many_dispatch 等待调度(结果)

文件“/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/asgiref/sync.py”,第 244 行,调用中 返回等待 asyncio.wait_for(future, timeout=None)

文件“/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/asyncio/tasks.py”,第414行,在wait_for return await fut

文件“/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/concurrent/futures/thread.py”,第 57 行,运行结果 = self.fn(*self.args, **self.夸格斯)

文件“/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/channels/db.py”,第 14 行,在 thread_handler return super().thread_handler(loop, *args, * *夸格斯)

文件“/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/asgiref/sync.py”,第 277 行,在 thread_handler return func(*args, **kwargs)

文件“/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/channels/consumer.py”,第 107 行,在 dispatch raise ValueError("No handler for message type %s" %消息[“类型”])

没有消息类型 app_consumer.notification_message 的处理程序

标签: pythondjangodjango-channels

解决方案


您在这里发出的是您的notification_message处理程序方法的名称。

Channels 期望它被命名为app_consumer_notification_message.

Channels在查找消息处理方法时将.in 消息类型替换为。_

(消息类型中的前缀不用于仅路由组名称)


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