我想 Build 一个聊天演示,但我无法收到服务器端发送的东西,除了第一次启动,有谁知道为什么?代码来自https://docs.python.org/3.4/library/asyncio-protocol.html#tcp-echo-client-protocol
Server.py
import asyncio
class EchoServerClientProtocol(asyncio.Protocol):
def connection_made(self, transport):
peername = transport.get_extra_info('peername')
print('Connection from {}'.format(peername))
self.transport = transport
def data_received(self, data):
message = data.decode()
print('Data received: {!r}'.format(message))
print('Send: {!r}'.format(message))
self.transport.write(data)
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, message, loop):
self.message = message
self.loop = loop
self.transport = None
def connection_made(self, transport):
self.transport = transport
transport.write(self.message.encode())
print('Data sent: {!r}'.format(self.message))
# while 1:
# message=input('please input the message:')
# transport.write(message.encode())
# print('Data sent: {!r}'.format(message))
def data_received(self, data):
# print('data_received')
print('Data received: {!r}'.format(data.decode()))
while 1:
message = input('please input the 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()
loop = asyncio.get_event_loop()
message = 'Hello World!'
coro = loop.create_connection(lambda: EchoClientProtocol(message, loop),
'127.0.0.1', 8888)
loop.run_until_complete(coro)
loop.run_forever()
loop.close()
结果显示:无法显示'Data received: ' ##### ' like ' def data_received(self,data)'仅用于任何人有解决方案吗? [结果] [1] [1]:https://i.stack.imgur.com/IoqA9.png
1 回答
您从
EchoClientProtocol.data_received()
创建了所谓的阻止功能 . 只有当事件循环可以处理它但阻塞功能阻止它时,来自服务器的每个传递的消息都可以传递到EchoClientProtocol.data_received()
.这段代码
从用户那里获取消息并将其发送到服务器,直到这一刻它一切正常 . 在下一步中,它会启动另一个循环,但代码永远不会进入事件循环(因此无法处理传入的消息) .
您可以像这样编辑客户端代码:
当您从服务器收到
Hello World!
时,首先调用data_received
客户端(它是从connection_made
发送的Hello World!
) . 现在处理如下:打印收到的消息(在第一次调用中是
Hello World!
)从用户那里获取新消息
将其发送到服务器
该函数返回并且控件被赋予事件循环 .
服务器收到新消息并将其发送回客户端
客户端调用
data_received
上的事件循环转到步骤1