gistfile1.txt

#!/usr/bin/python2
import multiprocessing
import socket
import time
import os

def handle(socket):
    import logging
    logging.basicConfig(level=logging.DEBUG)

    while True:
        connection, address = socket.accept()
        logger = logging.getLogger("process-%r" % os.getpid())
        try:
            logger.debug("Connected %r at %r", connection, address)
            while True:
                data = connection.recv(1024)
                if data == "":
                    logger.debug("Socket closed remotely")
                    break
                logger.debug("Received data %r", data)
                connection.sendall(data)
                logger.debug("Sent data")
        except:
            logger.exception("Problem handling request")
        finally:
            logger.debug("Closing socket")
            connection.close()

class Server(object):
    def __init__(self, hostname, port, child):
        import logging
        self.logger = logging.getLogger("server")
        self.hostname = hostname
        self.port = port
        self.child = child
        self.processes = []

    def spawn(self):
        process = multiprocessing.Process(target=handle, args=(self.socket,))
        process.daemon = True
        process.start()
        return process

    def start(self):
        self.socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        self.socket.bind((self.hostname, self.port))
        self.socket.listen(3)
        self.logger.debug("listening")

        for _ in range(self.child):
            self.processes.append(self.spawn())

        self.logger.debug("prefork %d child processes" %len(self.processes))

        while True:
            for i in range(self.child):
                self.processes[i].join(1)
                if not self.processes[i].is_alive():
                    self.logger.debug("restarted a child")
                    self.processes[i] = self.spawn()

if __name__ == "__main__":
    import logging
    logging.basicConfig(level=logging.DEBUG)
    server = Server("0.0.0.0", 9000, 20)
    try:
        logging.info("Listening")
        server.start()
    except:
        logging.exception("Unexpected exception")
    finally:
        logging.info("Shutting down")
        for process in multiprocessing.active_children():
            logging.info("Shutting down process %r", process)
            process.terminate()
            process.join()
    logging.info("All done")