django channels

django channels 是django支持websocket的一个模块。

1. 安装

`pip3 install channels`

2. 快速上手

2.1 在settings中添加配置

INSTALLED_APPS = [
'django.contrib.admin',
'django.contrib.auth',
'django.contrib.contenttypes',
'django.contrib.sessions',
'django.contrib.messages',
'django.contrib.staticfiles',
'channels',
]

ASGI_APPLICATION = "django_channels_demo.routing.application"

2.2 创建websocket应用和路由

#!/usr/bin/env python
# -*- coding:utf-8 -*-
from channels.routing import ProtocolTypeRouter, URLRouter
from django.conf.urls import url
from chat import consumers
application = ProtocolTypeRouter({
'websocket': URLRouter([
url(r'^chat/$', consumers.ChatConsumer),
])
})

2.3 编写处理websocket逻辑业务

#!/usr/bin/env python
# -*- coding:utf-8 -*-
from channels.generic.websocket import WebsocketConsumer
from channels.exceptions import StopConsumer
class ChatConsumer(WebsocketConsumer):
def websocket_connect(self, message):
self.accept()
def websocket_receive(self, message):
print('接收到消息', message)
self.send(text_data='收到了')
def websocket_disconnect(self, message):
print('客户端断开连接了')
raise StopConsumer()

#!/usr/bin/env python
# -*- coding:utf-8 -*-
from channels.generic.websocket import WebsocketConsumer
from channels.exceptions import StopConsumer
class SimpleChatConsumer(WebsocketConsumer):
def connect(self):
self.accept()
def receive(self, text_data=None, bytes_data=None):
self.send(text_data)
# 主动断开连接
# self.close()
def disconnect(self, code):
print('客户端要断开了')

#!/usr/bin/env python
# -*- coding:utf-8 -*-
from channels.generic.websocket import WebsocketConsumer
from channels.exceptions import StopConsumer
CLIENTS = []
class ChatConsumer(WebsocketConsumer):
def connect(self):
self.accept()
CLIENTS.append(self)
def receive(self, text_data=None, bytes_data=None):
for item in CLIENTS:
item.send(text_data)
# 主动断开连接
# self.close()
def disconnect(self, code):
CLIENTS.remove(self)

3. channel layer

基于内存的channel layer

CHANNEL_LAYERS = {
"default": {
"BACKEND": "channels.layers.InMemoryChannelLayer",
}
}

from channels.generic.websocket import WebsocketConsumer
from asgiref.sync import async_to_sync
class ChatConsumer(WebsocketConsumer):
def connect(self):
async_to_sync(self.channel_layer.group_add)('x1', self.channel_name)
self.accept()
def receive(self, text_data=None, bytes_data=None):
async_to_sync(self.channel_layer.group_send)('x1', {
'type': 'xxx.ooo',
'message': text_data
})
def xxx_ooo(self, event):
message = event['message']
self.send(message)
def disconnect(self, code):
async_to_sync(self.channel_layer.group_discard)('x1', self.channel_name)

基于 redis的channel layer

`pip3 install channels``-``redis`

CHANNEL_LAYERS = {
"default": {
"BACKEND": "channels_redis.core.RedisChannelLayer",
"CONFIG": {
"hosts": [('10.211.55.25', 6379)]
},
},
}
CHANNEL_LAYERS = {
'default': {
'BACKEND': 'channels_redis.core.RedisChannelLayer',
'CONFIG': {"hosts": ["redis://10.211.55.25:6379/1"],},
},
}

CHANNEL_LAYERS = {
'default': {
'BACKEND': 'channels_redis.core.RedisChannelLayer',
'CONFIG': {"hosts": [('10.211.55.25', 6379)],},},
}

CHANNEL_LAYERS = {
"default": {
"BACKEND": "channels_redis.core.RedisChannelLayer",
"CONFIG": {
"hosts": ["redis://:password@10.211.55.25:6379/0"],
"symmetric_encryption_keys": [SECRET_KEY],
},
},
}

from channels.generic.websocket import WebsocketConsumer
from asgiref.sync import async_to_sync
class ChatConsumer(WebsocketConsumer):
def connect(self):
async_to_sync(self.channel_layer.group_add)('x1', self.channel_name)
self.accept()
def receive(self, text_data=None, bytes_data=None):
async_to_sync(self.channel_layer.group_send)('x1', {
'type': 'xxx.ooo',
'message': text_data
})
def xxx_ooo(self, event):
message = event['message']
self.send(message)
def disconnect(self, code):
async_to_sync(self.channel_layer.group_discard)('x1', self.channel_name)