timeout for Python (signal, futures)

timeout.py

import os
import time
from concurrent import futures
import signal


class Model:
    def __init__(self):
        self.pid = os.getpid()

    def run(self):
        time.sleep(1)
        print('>> run: ', os.getpid())
        return self.pid

    def __repr__(self):
        return f'<{self.pid}>'


m = Model()
print(m)

# signal


def handler(signum, frame):
    raise TimeoutError('Timeout')


signal.signal(signal.SIGALRM, handler)
try:
    signal.alarm(2)
    m.run()
    signal.alarm(0)
except TimeoutError as err:
    print('signal', err)


# async

with futures.ProcessPoolExecutor(max_workers=1) as pool:
    try:
        f = pool.submit(m.run)
        print(f.result(timeout=0.1))
    except futures.TimeoutError as err:
        print('try to cancel:', f.cancel())
        print('async timeout:', err)

• https://stackoverflow.com/a/494273
  • signal.alarm is not available in Windows
• https://stackoverflow.com/a/26414982
  • futures is not able to cancel when it's running (unless you add event check)