Django 频道：发送和接收任务位置参数

Question

目前我正在使用 django 频道开发实时聊天系统，但我面临以下提到的问题。请告诉我如何解决下面提到的问题。

频道==4.0.0

这是我的 Consumer.py `

import json
from channels.generic.websocket import AsyncWebsocketConsumer


class ChatConsumer(AsyncWebsocketConsumer):
    def __init__(self, *args, **kwargs):
        super().__init__(args, kwargs)
        self.booking_id = None
        self.booking_group_name = None

    async def connect(self):
        self.booking_id = 2
        self.booking_group_name = 'chat_%s' % self.booking_id

        # Join booking group
        await self.channel_layer.group_add(
            self.booking_group_name,
            self.channel_name
        )
        await self.accept()

    async def disconnect(self, close_code):
        # Leave booking group
        await self.channel_layer.group_discard(
            self.booking_group_name,
            self.channel_name
        )

    # Receive message from WebSocket

    async def receive(self, text_data=None, bytes_data=None):
        text_data_json = json.loads(text_data)
        sender = self.scope['user']
        message = text_data_json['message']

        # Save chat message to database
        await self.save_chat_message(sender, message)

        # Send message to booking group
        await self.channel_layer.group_send(
            self.booking_group_name,
            {
                'type': 'chat_message',
                'sender': sender.username,
                'message': message
            }
        )

    async def chat_message(self, event):
        sender = event['sender']
        message = event['message']

        # Send message to WebSocket
        await self.send(text_data=json.dumps({
            'sender': sender,
            'message': message
        }))

    def save_chat_message(self, sender, message):
        from booking.models import Booking, CustomerSupportCollection, CustomerSupportChat
        booking = Booking.objects.get(id=self.booking_id)
        collection = CustomerSupportCollection.objects.get_or_create(
            booking=booking,
        )
        chat_message = CustomerSupportChat.objects.create(
            booking=booking,
            collection=collection,
            user=sender,
            message=message
        )
        return chat_message
`

asgi.py

"""
ASGI config for cleany project.

It exposes the ASGI callable as a module-level variable named ``application``.

For more information on this file, see
https://docs.djangoproject.com/en/3.2/howto/deployment/asgi/
"""

import os
import os
from django.core.asgi import get_asgi_application
from channels.routing import ProtocolTypeRouter, URLRouter
from channels.auth import AuthMiddlewareStack
from .routing import websocket_urlpatterns

os.environ.setdefault("DJANGO_SETTINGS_MODULE", "cleany.settings")

django_asgi_app = get_asgi_application()


application = ProtocolTypeRouter({
    "http": get_asgi_application(),
    "websocket": AuthMiddlewareStack(
        URLRouter(
            websocket_urlpatterns
        )
    )
})

路由.py

from django.urls import re_path, path
from django_private_chat2 import consumers

from cleany.consumer import ChatConsumer

websocket_urlpatterns = [
    re_path(r'ws/chat/$', ChatConsumer.as_asgi()),
]

但是它显示这个错误：

实际上我尝试了 django 频道进行实时聊天，但我遇到了这个错误。

Answer 1

错误解释：

只是试图解释此错误消息是否来自：这看起来您正在通过 wsgi 而不是 asgi 使用 runserver 运行应用程序。此外，您似乎向 http://localhost:8000/ws/chat 而不是 ws://localhost:8000/ws/chat 发出了普通的 http 请求。最后我想你在 urls.py 中有一个 urlpattern 如下所示，它捕获 http 请求并导致错误，因为通过 wsgi 不需要属性发送和接收（wsgi 类 bassed 视图有一个 as_wsgi() 方法）。

urlpatterns = [
    re_path(r'ws/chat/$', ChatConsumer.as_asgi()),   # as_asgi() must not be used in urlpattners for wsgi
]

如果您开始使用 ChatConsumer 并且还没有了解如何使用 asgi 的全貌，那可能是某个阶段遗留下来的。

至少 asgi.py 现在没有参与整个事情。

解决方案：

你需要做以下事情： (https://channels.readthedocs.io/en/stable/installation.html)

1. 安装频道和 daphne（异步服务器）

pip uninstall channels
python -m pip install -U channels["daphne"]

2. 在 settings.py 中将 daphne（仅）添加到已安装的应用程序中：

INSTALLED_APPS = (
    "daphne",
    ...

3. 在 settings.py 中添加 ASGI_APPLICATION:

WSGI_APPLICATION = "xxxx.wsgi.application"
ASGI_APPLICATION = "xxxx.asgi.application"

4. 在 asg.py 中

application = ProtocolTypeRouter({
    "http": get_asgi_application(),
    "websocket": AuthMiddlewareStack(
        URLRouter(
            websocket_urlpatterns
        )
    )
})

5. 现在调用 `python manage.py runserver' 这将自动启动 daphne/asgi 并且您可以连接 ws

...当然你可以使用其他 asgi 服务器然后 daphne