#

# Example where a pool of http servers share a single listening socket

#

# On Windows this module depends on the ability to pickle a socket

# object so that the worker processes can inherit a copy of the server

# object.  (We import `multiprocessing.reduction` to enable this pickling.)

#

# Not sure if we should synchronize access to `socket.accept()` method by

# using a process-shared lock -- does not seem to be necessary.

#

import os

import sys

from multiprocessing import Process, current_process, freeze_support

from BaseHTTPServer import HTTPServer

from SimpleHTTPServer import SimpleHTTPRequestHandler

if sys.platform == 'win32':

    import multiprocessing.reduction    # make sockets pickable/inheritable

def note(format, *args):

    sys.stderr.write('[%s]\t%s\n' % (current_process().name, format%args))

class RequestHandler(SimpleHTTPRequestHandler):

    # we override log_message() to show which process is handling the request

    def log_message(self, format, *args):

        note(format, *args)

def serve_forever(server):

    note('starting server')

    try:

        server.serve_forever()

    except KeyboardInterrupt:

        pass

def runpool(address, number_of_processes):

    # create a single server object -- children will each inherit a copy

    server = HTTPServer(address, RequestHandler)

    # create child processes to act as workers

    for i in range(number_of_processes-1):

        Process(target=serve_forever, args=(server,)).start()

    # main process also acts as a worker

    serve_forever(server)

def test():

    DIR = os.path.join(os.path.dirname(__file__), '..')

    ADDRESS = ('localhost', 8000)

    NUMBER_OF_PROCESSES = 4

    print 'Serving at http://%s:%d using %d worker processes' % \

          (ADDRESS[0], ADDRESS[1], NUMBER_OF_PROCESSES)

    print 'To exit press Ctrl-' + ['C', 'Break'][sys.platform=='win32']

    os.chdir(DIR)

    runpool(ADDRESS, NUMBER_OF_PROCESSES)

if __name__ == '__main__':

    freeze_support()

    test()