Django 中的 channels

Django Channels 

django channels 是django支持websocket的一個模塊。

1. 安裝

1	pip3 install channels

2. 快速上手 

2.1 在settings中添加配置

註冊channels的app

ASGI_APPLICATION = "django_channels_demo.routing.application"

添加ASGI_APPLICATION支持websocket

2.2 建立websocket應用和路由

 1 #!/usr/bin/env python
 2 # -*- coding:utf-8 -*-
 3 from channels.routing import ProtocolTypeRouter, URLRouter  4 from django.conf.urls import url  5 from chat import consumers  6 
 7 
 8 application = ProtocolTypeRouter({  9     'websocket': URLRouter([ 10         url(r'^chat/$', consumers.ChatConsumer), 11  ]) 12 })

應用和路由

2.3 編寫處理websocket邏輯業務

 1 #!/usr/bin/env python
 2 # -*- coding:utf-8 -*-
 3 from channels.generic.websocket import WebsocketConsumer  4 from channels.exceptions import StopConsumer  5 
 6 class ChatConsumer(WebsocketConsumer):  7 
 8     def websocket_connect(self, message):  9  self.accept() 10 
11     def websocket_receive(self, message): 12         print('接收到消息', message) 13         self.send(text_data='收到了') 14 
15     def websocket_disconnect(self, message): 16         print('客戶端斷開鏈接了') 17         raise StopConsumer()

示例一

 1 #!/usr/bin/env python
 2 # -*- coding:utf-8 -*-
 3 from channels.generic.websocket import WebsocketConsumer  4 from channels.exceptions import StopConsumer  5 
 6 
 7 class SimpleChatConsumer(WebsocketConsumer):  8     def connect(self):  9  self.accept() 10 
11     def receive(self, text_data=None, bytes_data=None): 12  self.send(text_data) 13 
14         # 主動斷開鏈接
15         # self.close()
16 
17     def disconnect(self, code): 18         print('客戶端要斷開了') 19 
20 示例二

示例二

 1 #!/usr/bin/env python
 2 # -*- coding:utf-8 -*-
 3 from channels.generic.websocket import WebsocketConsumer  4 from channels.exceptions import StopConsumer  5 
 6 
 7 CLIENTS = []  8 
 9 class ChatConsumer(WebsocketConsumer): 10 
11     def connect(self): 12  self.accept() 13  CLIENTS.append(self) 14 
15     def receive(self, text_data=None, bytes_data=None): 16         for item in CLIENTS: 17  item.send(text_data) 18 
19         # 主動斷開鏈接
20         # self.close()
21 
22     def disconnect(self, code): 23  CLIENTS.remove(self) 24 
25 示例三

示例三

3. channel layer

 基於內存的channel layer

1 CHANNEL_LAYERS = { 2     "default": { 3         "BACKEND": "channels.layers.InMemoryChannelLayer", 4  } 5 }

配置

 1 from channels.generic.websocket import WebsocketConsumer  2 from asgiref.sync import async_to_sync  3 
 4 
 5 class ChatConsumer(WebsocketConsumer):  6 
 7     def connect(self):  8         async_to_sync(self.channel_layer.group_add)('x1', self.channel_name)  9  self.accept() 10 
11     def receive(self, text_data=None, bytes_data=None): 12         async_to_sync(self.channel_layer.group_send)('x1', { 13             'type': 'xxx.ooo', 14             'message': text_data 15  }) 16 
17     def xxx_ooo(self, event): 18         message = event['message'] 19  self.send(message) 20 
21     def disconnect(self, code): 22         async_to_sync(self.channel_layer.group_discard)('x1', self.channel_name) 23 
24 業務處理

業務處理

基於 redis的channel layer

pip3 install channels-redis

 1 CHANNEL_LAYERS = {  2     "default": {  3         "BACKEND": "channels_redis.core.RedisChannelLayer",  4         "CONFIG": {  5             "hosts": [('10.211.55.25', 6379)]  6  },  7  },  8 }  9 
10 
11 CHANNEL_LAYERS = { 12     'default': { 13     'BACKEND': 'channels_redis.core.RedisChannelLayer', 14     'CONFIG': {"hosts": ["redis://10.211.55.25:6379/1"],}, 15  }, 16 } 17  
18 
19 CHANNEL_LAYERS = { 20     'default': { 21     'BACKEND': 'channels_redis.core.RedisChannelLayer', 22     'CONFIG': {"hosts": [('10.211.55.25', 6379)],},}, 23 } 24  
25 
26 CHANNEL_LAYERS = { 27     "default": { 28         "BACKEND": "channels_redis.core.RedisChannelLayer", 29         "CONFIG": { 30             "hosts": ["redis://:password@10.211.55.25:6379/0"], 31             "symmetric_encryption_keys": [SECRET_KEY], 32  }, 33  }, 34 } 35 
36 配置

配置

 1 from channels.generic.websocket import WebsocketConsumer  2 from asgiref.sync import async_to_sync  3 
 4 
 5 class ChatConsumer(WebsocketConsumer):  6 
 7     def connect(self):  8         async_to_sync(self.channel_layer.group_add)('x1', self.channel_name)  9  self.accept() 10 
11     def receive(self, text_data=None, bytes_data=None): 12         async_to_sync(self.channel_layer.group_send)('x1', { 13             'type': 'xxx.ooo', 14             'message': text_data 15  }) 16 
17     def xxx_ooo(self, event): 18         message = event['message'] 19  self.send(message) 20 
21     def disconnect(self, code): 22         async_to_sync(self.channel_layer.group_discard)('x1', self.channel_name) 23 
24 業務邏輯

業務處理