gistfile1.py

from sys import executable
from os import environ
from twisted.internet import reactor, defer
from twisted.internet.protocol import Protocol
from twisted.internet.protocol import Factory
from twisted.internet import protocol
from twisted.protocols.basic import LineReceiver
import sys
import time
import Queue
import os

implementation = """
import os
import time
import sys
import string
def censor():
        BW = ["sfs", "fsdfwe", "tryt", "sfsvx"]
        while (True):
            a = sys.stdin.readline()
            if a:
                   for bannedWord in BW:
                        a = string.replace(a, bannedWord , '<banned>')
                   sys.stdout.write(a)
                   sys.stdout.flush()
"""

class Echo(LineReceiver):
        def lineReceived(self, data):
            d = self.factory.process.sendData(data+'\r\n')
            #reactor.callLater(3,d.addCallback, printData)
            d.addCallback(printData)
            prot.transport.write(data)

def createProcess():
    pp = censoringProtocol()
    Process = reactor.spawnProcess(pp, executable, [executable, "-c", implementation], env=environ, childFDs = {0:"w", 1:"r", 2:"r"})
    pp.process = Process
    return pp    

class EchoFactory(Factory): 
      protocol = Echo 
      telnetConnectionList  = []
      process  = None
      deferQ   = None

      def __init__(self):
          EchoFactory.process = createProcess()
          EchoFactory.deferQ  = Queue.Queue()
      def buildProtocol (self, addr):
          newProtocol = Factory.buildProtocol(self, addr)
          EchoFactory.telnetConnectionList.append(newProtocol)
          return newProtocol

class censoringProtocol(protocol.ProcessProtocol):

    def __init__(self):
        self.process = None

    def connectionMade(self):
        print "connectionMade!"

    def outReceived(self, data):
        EchoFactory.deferQ.get().callback(data)

    def sendData(self,data):
        d = defer.Deferred()
        EchoFactory.deferQ.put(d)
        self.process.writeToChild(0, data)
        return d



reactor.listenTCP(11111, EchoFactory())
print 'in parent', os.getpid()
reactor.run()