【发布时间】：2015-04-10 22:42:54
【问题描述】：
我想实现一个 TCP/IP 网络客户端应用程序，它将请求发送到 Python SocketServer 并期望得到响应。我已经开始使用官方 Python SocketServer sample code:
server.py:
#!/usr/bin/env python
# encoding: utf-8
import SocketServer
class MyTCPHandler(SocketServer.StreamRequestHandler):
def handle(self):
request = self.rfile.readline().strip()
print "RX [%s]: %s" % (self.client_address[0], request)
response = self.processRequest(request)
print "TX [%s]: %s" % (self.client_address[0], response)
self.wfile.write(response)
def processRequest(self, message):
if message == 'request type 01':
return 'response type 01'
elif message == 'request type 02':
return 'response type 02'
if __name__ == "__main__":
server = SocketServer.TCPServer(('localhost', 12345), MyTCPHandler)
server.serve_forever()
client.py:
#!/usr/bin/env python
# encoding: utf-8
import socket
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
try:
sock.connect(('127.0.0.1', 12345))
data = 'request type 01'
sent = sock.sendall(data + '\n')
if sent == 0:
raise RuntimeError("socket connection broken")
received = sock.recv(1024)
print "Sent: {}".format(data)
print "Received: {}".format(received)
data = 'request type 02'
sent = sock.sendall(data + '\n')
if sent == 0:
raise RuntimeError("socket connection broken")
received = sock.recv(1024)
print "Sent: {}".format(data)
print "Received: {}".format(received)
except Exception as e:
print e
finally:
sock.close()
server.py 输出：
RX [127.0.0.1]: request type 01
TX [127.0.0.1]: response type 01
client.py 输出：
Sent: request type 01
Received: response type 01
[Errno 54] Connection reset by peer
做错了什么？似乎服务器正在关闭连接。我怎样才能让它保持打开状态？
注意：这是C++/Qt: QTcpSocket won't write after reading的后续问题
更新（abarnert's answer之后）：
我从中得出的结论是，SocketServer.StreamRequestHandler 不是最新的设计，虽然它允许我通过网络连接，但它并不能真正支持我需要的所有 TCP/IP 相关方面注意实现稳健的沟通。
这已在 Python 3 中通过 asyncio 解决，但由于项目存在于 Python 2 中，因此无法选择。因此，我在Twisted 中实现了上面描述的服务器和客户端：
server.py:
#!/usr/bin/env python
# encoding: utf-8
from twisted.internet.protocol import Factory
from twisted.protocols.basic import LineReceiver
from twisted.internet import reactor
class SimpleProtocol(LineReceiver):
def connectionMade(self):
print 'connectionMade'
# NOTE: lineReceived(...) doesn't seem to get called
def dataReceived(self, data):
print 'dataReceived'
print 'RX: %s' % data
if data == 'request type 01':
response = 'response type 01'
elif data == 'request type 02':
response = 'response type 02'
else:
response = 'unsupported request'
print 'TX: %s' % response
self.sendLine(response)
class SimpleProtocolFactory(Factory):
def buildProtocol(self, addr):
return SimpleProtocol()
reactor.listenTCP(12345, SimpleProtocolFactory(), interface='127.0.0.1')
reactor.run()
client.py:
#!/usr/bin/env python
# encoding: utf-8
from twisted.internet import reactor
from twisted.internet.protocol import Protocol
from twisted.internet.endpoints import TCP4ClientEndpoint, connectProtocol
class SimpleClientProtocol(Protocol):
def sendMessage(self, msg):
print "[TX]: %s" % msg
self.transport.write(msg)
def gotProtocol(p):
p.sendMessage('request type 01')
reactor.callLater(1, p.sendMessage, 'request type 02')
reactor.callLater(2, p.transport.loseConnection)
point = TCP4ClientEndpoint(reactor, '127.0.0.1', 12345)
d = connectProtocol(point, SimpleClientProtocol())
d.addCallback(gotProtocol)
reactor.run()
客户端不会关闭，而是闲置直到 CTRL+C。 Twisted 可能需要一段时间才能理解，但对于手头的工作，使用经过测试和尝试的框架显然比自己完成所有这些基础工作更合理。
【问题讨论】：
标签： python sockets tcp network-programming twisted