如何通过 Django Channels 使用多个 websocket 连接？

我已经愉快地使用 Django-Channels 几个月了。但是，我在 Django 项目中添加了第二个依赖于 websocket 的应用程序，但遇到了麻烦。

我得到的错误是websocket connection failed websocket is closed before the connection is established。奇怪的是，第一个应用程序在部署第二个应用程序之前就已经运行了。此外，只要第二应用程序不运行，第一应用程序就继续工作。

The Django 频道文档 https://channels.readthedocs.io/en/latest/topics/routing.html#routing says:

Channels routers only work on the scope level, not on the level of individual events, which means you can only have one consumer for any given connection. Routing is to work out what single consumer to give a connection, not how to spread events from one connection across multiple consumers.

我认为这意味着 Django-Channels 不支持多个 websocket 连接的路由。也就是说，我想我正在尝试对两个不同的应用程序使用相同的 websocket 连接/端口。我的routing.py文件如下所示：

application = ProtocolTypeRouter({
    "websocket": AuthMiddlewareStack(
        URLRouter([
            path("first_application/stream/", app_1_consumers.AsyncApp1),
            path("second_application/stream/", app_2_consumers.AsyncApp2),
        ])
    )
})

当我尝试使用下面的设置时，它找不到第一个应用程序的路径：

application = ProtocolTypeRouter({
    "websocket": AuthMiddlewareStack(
        URLRouter([
            path("second_application/stream/", app_2_consumers.AsyncApp2),
        ])
    ),
    "websocket02": AuthMiddlewareStack(
        URLRouter([
            path("first_application/stream/", app_1_consumers.AsyncApp1),
        ])
    ),

})

如何设置我的 Django 应用程序以使用 Django-Channels 提供两个不同的 websocket 连接？是否可以？或者我只是配置不当？

根据他们的实施和文档（here https://channels.readthedocs.io/en/latest/topics/routing.html#protocoltyperouter), 的值ProtocolTypeRouter是一个地图/字典，它们监听或查看的只是两种类型的键：

ProtocolTypeRouter({
   "http": some_app,
   "websocket": some_other_app,
})

这就导致了这样一个事实：如果你传递不同的密钥，比如websocket02不起作用。这显然意味着必须有一种方法可以通过同一个 websocket 组合两个 APP url 并创建单独的端点。

事实上，你可以做的是，就像他们提到的那样：

from django.conf.urls import url

from channels.routing import ProtocolTypeRouter, URLRouter
from channels.auth import AuthMiddlewareStack

application = ProtocolTypeRouter({

    # WebSocket chat handler
    "websocket": AuthMiddlewareStack(
        URLRouter([
            url(r"^first_application/stream/$", app_2_consumers.AsyncApp1Consumer),
            url(r"^second_application/stream/$", app_2_consumers.AsyncApp2Consumer),
        ])
    ),

})

上面的示例基于两个端点的实现（here https://github.com/django/channels/blob/master/docs/topics/routing.rst#routing):

application = ProtocolTypeRouter({

    # WebSocket chat handler
    "websocket": AuthMiddlewareStack(
        URLRouter([
            url(r"^chat/admin/$", AdminChatConsumer),
            url(r"^chat/$", PublicChatConsumer),
        ])
    ),
})

OR

同一websocket下基于不同通道的路由：https://github.com/django/channels/blob/master/docs/topics/routing.rst#channelnamerouter https://github.com/django/channels/blob/master/docs/topics/routing.rst#channelnamerouter