timeout-demo.py

import os
from multiprocessing.pool import Pool, TimeoutError
import signal
import functools
import time


class TimeoutFunc(object):
    def __init__(self, func, duration, ctimeout):
        self.func = func
        self.duration = duration
        self.ctimeout = ctimeout

    def handler(self, signum, frame):
        self.ctimeout()
        raise TimeoutError

    def __call__(self, *args, **kw):
        old_handler = signal.signal(signal.SIGALRM, self.handler)
        signal.alarm(self.duration)
        try:
            return self.func(*args, **kw)
        finally:
            signal.signal(signal.SIGALRM, old_handler)
            signal.alarm(0)


class TimeoutPool(Pool):
    def async_with_timeout(self, func, args, callback, duration, ctimeout):
        wrapped = TimeoutFunc(func, duration, ctimeout)
        return self.apply_async(wrapped, args, callback=callback)



def f(x):
    print('start %d' % os.getpid())
    try:
        time.sleep(1.1)
        return x*x
    finally:
        print('end %d' % os.getpid())

def ok(result):
    print(result)


def timedout():
    print("timeout!")


pool = TimeoutPool(processes=2)

pool.async_with_timeout(f, (10,), callback=ok, duration=10,
                        ctimeout=timedout)

pool.async_with_timeout(f, (2,), callback=ok, duration=1,
                        ctimeout=timedout)

pool.close()
pool.join()