首先，我们用webpy写一个简单的网站，监听8080端口，返回“hello, everet.org”的页面。
然后我们使用我们的forwarding.py，在80端口和8080端口中间建立两条通信管道用于双向通信。
此时，我们通过80端口访问我们的服务器。
浏览器得到：
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然后，我们在forwarding.py的输出结果中可以看到浏览器和webpy之间的通信内容。
代码：
#!/usr/bin/env python
import sys, socket, time, threading
loglock = threading.Lock()
def log(msg):
loglock.acquire()
try:
print '[%s]: \n%s\n' % (time.ctime(), msg.strip())
sys.stdout.flush()
finally:
loglock.release()
class PipeThread(threading.Thread):
def __init__(self, source, target):
threading.Thread.__init__(self)
self.source = source
self.target = target
def run(self):
while True:
try:
data = self.source.recv(1024)
log(data)
if not data: break
self.target.send(data)
except:
break
log('PipeThread done')
class Forwarding(threading.Thread):
def __init__(self, port, targethost, targetport):
threading.Thread.__init__(self)
self.targethost = targethost
self.targetport = targetport
self.sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
self.sock.bind(('0.0.0.0', port))
self.sock.listen(10)
def run(self):
while True:
client_fd, client_addr = self.sock.accept()
target_fd = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
target_fd.connect((self.targethost, self.targetport))
log('new connect')
# two direct pipe
PipeThread(target_fd, client_fd).start()
PipeThread(client_fd, target_fd).start()
if __name__ == '__main__':
print 'Starting'
import sys
try:
port = int(sys.argv[1])
targethost = sys.argv[2]
try: targetport = int(sys.argv[3])
except IndexError: targetport = port
except (ValueError, IndexError):
print 'Usage: %s port targethost [targetport]' % sys.argv[0]
sys.exit(1)
#sys.stdout = open('forwaring.log', 'w')
Forwarding(port, targethost, targetport).start() 
