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我正在使用 DRF 3.11.0 和 Channels 2.4.0 的组合来实现后端，它托管在 Heroku 上的 1 dyno 上，并附加了 Redis 资源。我的 React 前端有一个套接字，它成功地从后端服务器发送/接收。

我遇到了一个问题，即通过套接字发送回前端的任何消息都被发送了两次。我已经确认console.log前端只ping后端一次。我可以通过print()API 调用内部确认该函数也只调用async_to_sync(channel_layer.group_send)一次。问题来自我的消费者 - 当我使用print(self.channel_name)inside of 时share_document_via_videocall()，我可以看到两个具有不同self.channel_names 的实例被调用 (specific.AOQenhTn!fUybdYEsViaP和specific.AOQenhTn!NgtWxuiHtHBw。看起来消费者已经连接到两个单独的通道，但我不确定为什么。当我print()在我的声明中connect()只看到它通过连接过程一次。

如何确保我只连接到一个频道？

在settings.py：

CHANNEL_LAYERS = {
    'default': {
        'BACKEND': 'channels_redis.core.RedisChannelLayer',
        'CONFIG': {
            #"hosts": [('127.0.0.1', 6379)],
            "hosts": [(REDIS_HOST)],
        },
    },
}

消费者：

import json
from asgiref.sync import async_to_sync
from channels.db import database_sync_to_async

from channels.generic.websocket import AsyncWebsocketConsumer
from rest_framework.authtoken.models import Token
from django.contrib.auth.models import AnonymousUser
from .exceptions import ClientError
import datetime
from django.utils import timezone

class HeaderConsumer(AsyncWebsocketConsumer):
    async def connect(self):
        print("connecting")

        await self.accept()
        print("starting")
        print(self.channel_name)
        await self.send("request_for_token")


    async def continue_connect(self):
        print("continuing")
        print(self.channel_name)

        await self.get_user_from_token(self.scope['token'])

        await self.channel_layer.group_add(
            "u_%d" % self.user['id'],
            self.channel_name,
        )
        #... more stuff


    async def disconnect(self, code):
        await self.channel_layer.group_discard(
            "u_%d" % self.user['id'],
            self.channel_name,
        )


    async def receive(self, text_data):
        text_data_json = json.loads(text_data)
        if 'token' in text_data_json:
            self.scope['token'] = text_data_json['token']
            await self.continue_connect()


    async def share_document_via_videocall(self, event):

        # Send a message down to the client
        print("share_document received")
        print(event)
        print(self.channel_name)
        print(self.user['id'])

        await self.send(text_data=json.dumps(
            {
                "type": event['type'],
                "message": event["message"],
            },
        ))

    @database_sync_to_async
    def get_user_from_token(self, t):
        try:
            print("trying token" + t)
            token = Token.objects.get(key=t)
            self.user = token.user.get_profile.json()
        except Token.DoesNotExist:
            print("failed")
            self.user = AnonymousUser()

REST API 调用：

class ShareViaVideoChat(APIView):
    permission_classes = (permissions.IsAuthenticated,)

    def post(self, request, format=None):
        data = request.data
        recipient_list = data['recipient_list']

        channel_layer = get_channel_layer()
        for u in recipient_list:
            if u['id'] != None:
                print("sending to:")
                print('u_%d' % u['id'])
                async_to_sync(channel_layer.group_send)(
                    'u_%d' % u['id'],
                    {'type': 'share_document_via_videocall',
                     'message': {
                             'document': {'data': {}},
                             'sender': {'name': 'some name'}
                         }
                     }
                )

        return Response()
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1 回答 1

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关于您拨打不同频道名称的电话，您确定您的前端没有两次连接到消费者吗？在浏览器中检查调试控制台。

于 2020-05-01T08:51:27.207 回答