asyncio Protocol

asyncio 模块的Protocol使用

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source code

[source code]

Protocol

1. 提供了几个'BaseProtocol', 'Protocol', 'DatagramProtocol''SubprocessProtocol' 实例

2. 基本的方法：

   connection_made()
   data_received() # 这个是类似于一个循环，循环调用者个方法来读取内容
   eof_received()
   connection_lost()
   

3. 启动顺序依次是

   State machine of calls:
    
    start -> CM [-> DR*] [-> ER?] -> CL -> end
    
   * CM: connection_made()
   * DR: data_received()
   * ER: eof_received()
   * CL: connection_lost()
   

create_server

1. create_server

    
   def create_server(self, protocol_factory, host=None, port=None, *,
            family=socket.AF_UNSPEC, flags=socket.AI_PASSIVE,
            sock=None, backlog=100, ssl=None, reuse_address=None,
            reuse_port=None):
    # 用来建立一个TCP 类型的Server,提供了默认的一些参数
    关于详细的内容可以查看asyncio.events 模块
    protocol_factory 我们使用asyncio.Protocol 来做工厂函数
   

connect_server/client

1. create_connection()

     def create_connection(self, protocol_factory, host=None, port=None, *,
                    ssl=None, family=0, proto=0, flags=0, sock=None,
                    local_addr=None, server_hostname=None):
   raise NotImplementedError
   

loop

1. asyncio事件循环

   loop = asyncio.get_event_loop()
   

Server.py

class EchoServerClientProtocol(asyncio.Protocol):
    def connection_made(self, transport):
        peername = transport.get_extra_info('peername')
        print('Connection from {}'.format(peername))
        self.transport = transport
        self.word_title = '我们一起来背诵 <<荷叶杯·记得那年花下>>'
        self.word_list = ['记得那年花下', '深夜', '初识谢娘时', '水堂西面画帘垂', '携手暗相期',
                          '惆怅晓莺残月', '相别', '从此隔音尘', '如今俱是异乡人', '相见更无因']
        self.index = 0
 
    def data_received(self, data):
        message = data.decode()
        print('Data received: {!r}'.format(message))
        try:
            message = self.find_next(data=data.decode())
            print('Send: {!r}'.format(message))
            self.transport.write(message.encode())
        except (IndexError,ValueError):
            message = input('input the message:')
            print('Send: {!r}'.format(message))
            self.transport.write(message.encode())
 
    def find_next(self, data):
        index = self.word_list.index(data)
        return self.word_list[index + 1]
 
 
loop = asyncio.get_event_loop()
# Each client connection will create a new protocol instance
coro = loop.create_server(EchoServerClientProtocol, '127.0.0.1', 8888)
server = loop.run_until_complete(coro)
 
# Serve requests until Ctrl+C is pressed
print('Serving on {}'.format(server.sockets[0].getsockname()))
try:
    loop.run_forever()
except KeyboardInterrupt:
    pass
 
# Close the server
server.close()
loop.run_until_complete(server.wait_closed())
loop.close()

client.py

class EchoClientProtocol(asyncio.Protocol):
    def __init__(self, loop):
        self.loop = loop
        self.transport = None
        self.word_title = '我们一起来背诵 <<荷叶杯·记得那年花下>>'
        self.word_list = ['记得那年花下', '深夜', '初识谢娘时', '水堂西面画帘垂', '携手暗相期',
                          '惆怅晓莺残月', '相别', '从此隔音尘', '如今俱是异乡人', '相见更无因']
        self.index = 0
        print(self.word_title)
 
    def connection_made(self, transport):
        self.transport = transport
        message = self.word_list[self.index]
        print('message: ',message)
        self.transport.write(message.encode())
 
    def data_received(self, data):
        print('Data received: {!r}'.format(data.decode()))
        try:
           message = self.find_next(data=data.decode())
           self.transport.write(message.encode())
           print('Data sent: {!r}'.format(message))
        except (IndexError,ValueError):
            message = input('input message:')
            self.transport.write(message.encode())
            print('Data sent: {!r}'.format(message))
 
 
 
    def connection_lost(self, exc):
        print('The server closed the connection')
        print('Stop the event loop')
        self.loop.stop()
 
    def find_next(self, data):
        index = self.word_list.index(data)
        return self.word_list[index + 1]
 
 
loop = asyncio.get_event_loop()
coro = loop.create_connection(lambda: EchoClientProtocol(loop),
                              '127.0.0.1', 8888)
loop.run_until_complete(coro)
loop.run_forever()
loop.close()