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：

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()