Django 通道 2 和信号：Websocket 连接失败

Question

我正在使用通道 2 和信号来检测何时保存某种类型的模型并向所有客户端推送通知。我收到错误消息：与 'ws:/account/home' 的 WebSocket 连接失败：WebSocket 在建立连接之前关闭。我不明白我在哪里犯了错误。非常感谢您的帮助。

在我的项目中：FUNDBOOK_V5/ROUTING.PY

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

application = ProtocolTypeRouter({
    # (http->django views is added by default)
    'websocket': AuthMiddlewareStack(
        URLRouter(
            FundBook_Core.routing.websocket_urlpatterns
        )
    ),
})

在我的应用程序中：FUNDBOOK_CORE\ROUTING.PY

from django.urls import re_path
from django.conf.urls import url

from . import consumers

websocket_urlpatterns = [
    url(r'^account/home/$', consumers.NotificationConsumer),
    url(r'^fund/(?P<fund>[\w-]+)/$', consumers.NotificationConsumer),
]

FUNDBOOK_CORE\CONSUMERS.PY

import json
import asyncio
from django.contrib.auth import get_user_model
from channels.generic.websocket import AsyncJsonWebsocketConsumer, AsyncConsumer


class NotificationConsumer(AsyncConsumer):

    async def websocket_connect(self, event):
        await self.channel_layer.group_add("task", self.channel_name)
        await self.send({
            "type": "websocket.accept"
        })
        print("Connected!", event)

    async def websocket_disconnect(self, event):
        await self.channel_layer.group_discard("task", self.channel_name)
        print("Disconnected!", event)

    async def send_message(self, event):
        await self.send({
            "type": "websocket.send",
            'text': 'Oy, mate!'
        })

SIGNALS.PY

from FundBook_Core.models import ThreadTask
from django.db.models.signals import pre_save
from django.dispatch import receiver
from asgiref.sync import async_to_sync
from channels.layers import get_channel_layer


@receiver(pre_save, sender=ThreadTask)
def notify_thread_task_save(sender, **kwargs):
    if "instance" in kwargs:
        instance = kwargs["instance"]
        # check if there is a new notification
        channel_layer = get_channel_layer()
        async_to_sync(channel_layer.group_send)(
            "task", {"type": "send_message",
                     "event": "New Notification",
                     "username": instance.username}
        )

FUNDBOOK_CORE\INIT.PY

default_app_config = "FundBook_Core.apps.FundbookCoreConfig"

FUNDBOOK_CORE\APPS.PY

from django.apps import AppConfig


class FundbookCoreConfig(AppConfig):
    name = 'FundBook_Core'

    def ready(self):
        from . import signals

SETTINGS.PY

ALLOWED_HOSTS = ['*']

ASGI_APPLICATION = 'FundBook_v5.routing.application'

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

HOME.HTML:

   <script>
        var loc = window.location;
        var wsStart = "ws://"
        if (loc.protocol === 'https:'){
            wsStart = 'wss://'
        }
        var url = wsStart + loc.host + loc.pathname;
        console.log(url)
        var socket = new ReconnectingWebSocket(url);

    socket.onmessage = function(e) {
        console.log("message", e)
        const data = JSON.parse(e.data);
        document.querySelector('#notifylist').value += (data.message + '\n');
    }
     socket.onopen = function(e) {
        console.log("open", e)
    }
     socket.onerror = function(e) {
        console.log("error", e)
         console.error('Notification socket closed unexpectedly')
    }
     socket.onclose = function(e) {
        console.log("close", e)
    }

    </script>

Answer 1

其实我有两个问题：第一个：ERR_CONNECTION_RESET 问题是由于防火墙阻止 websocket 连接或未配置为处理 websocket 连接而引起的。第二个错误：错误 - 服务器 - 应用程序内部异常：多个异常：[Errno 10061] Connect call failed ('::1', 6379), [Errno 10061] Connect call failed ('127. 0.0.1', 6379)来自 redit 数据库：见

在我解决了这些问题之后，一切正常。对于那些需要代码的人：

APP.初始化

default_app_config = "your_application.apps.FundbookCoreConfig"

APP.APPS

from django.apps import AppConfig


class your_appConfig(AppConfig):
name = 'your_app'

    def ready(self):
        from . import signals

PROJECT.SETTINGS

ASGI_APPLICATION = 'your_project.routing.application'

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

APP.SIGNALS

from django.db.models.signals import pre_save
from django.dispatch import receiver
from asgiref.sync import async_to_sync

from channels.layers import get_channel_layer
from.models import ThreadTask


@receiver(pre_save, sender=ThreadTask)
def notify_thread_task_save(sender, **kwargs):
    if "instance" in kwargs:
        instance = kwargs["instance"]
        # check if there is a new notification
        channel_layer = get_channel_layer()
        async_to_sync(channel_layer.group_send)(
            "task", {"type": "user_notification",
                     "event": "New Notification",
                     "notification": instance.text}
        )

PROJECT.ROUTING

from channels.auth import AuthMiddlewareStack
from channels.routing import ProtocolTypeRouter, URLRouter
from channels.security.websocket import AllowedHostsOriginValidator, OriginValidator
import your_app.routing

application = ProtocolTypeRouter({
    # (http->django views is added by default)
    'websocket': AllowedHostsOriginValidator(
        AuthMiddlewareStack(
            URLRouter(
                FundBook_Core.routing.websocket_urlpatterns
            )
        )
    ), 
})

APP.ROUTING

from django.conf.urls import url

from . import consumers

websocket_urlpatterns = [
    url(r'^account/home', consumers.NotificationConsumer),
    url(r'^fund/(?P<fund>[\w-]+)', consumers.NotificationConsumer),
]

APP.CONSUMERS

from channels.generic.websocket import AsyncJsonWebsocketConsumer


class NotificationConsumer(AsyncJsonWebsocketConsumer):

    async def connect(self):
        await self.accept()
        await self.channel_layer.group_add("task", self.channel_name)
        print(f"Added {self.channel_name} channel to task")

    async def disconnect(self, close_code):
        await self.channel_layer.group_discard("task", self.channel_name)
        print(f"Removed {self.channel_name} channel to task")

    async def user_notification(self, event):
        await self.send_json(event)
        print(f"Got message {event} at {self.channel_name}")

在你的html

<!-- Plugin JavaScript -->
<script src="{% static "FundBook_Core/js/reconnecting-websocket.js" %}"></script>

<script>
        var loc = window.location;
        var wsStart = "ws://"
        if (loc.protocol === 'https:'){
            wsStart = 'wss://'
        }
        var url = wsStart + loc.host + loc.pathname;
        console.log(url)
        var socket = new ReconnectingWebSocket(url);
        const tt = document.querySelector('#task_text');

        socket.onmessage = function(e) {
            console.log("message", e)
            const data = JSON.parse(e.data);
            console.log("parse", data)
            console.log("notification", data.notification)
            if(data.event == "New Notification"){
                 var el = document.createElement("li");
                 el.innerHTML = data.notification;
                 tt.appendChild(el);

            }


    }
     socket.onopen = function(e) {
        console.log("open", e)
    }
     socket.onerror = function(e) {
        console.log("error", e);
        console.error('Notification socket closed unexpectedly')
    }
     socket.onclose = function(e) {
        console.log("close", e)
    }

</script>

Django 通道 2 和信号：Websocket 连接失败

Django Channels 2 and Signals: Websocket Connections failed

django

signals

django-channels