.-test-py-futures-wait.py

#!/usr/bin/env python
from __future__ import print_function
# for python2.7 do `pip install futures`
from concurrent import futures
import sys
from time import sleep
from random import randint


def worker(i):
    result = randint(0, 10)
    sleep(result/10)
    if result == 1:
        raise NameError("foo")
    elif result == 2:
        return False
    return True

workers = 5
tasks = range(20)


print("INFO: Starting %s tasks..." % len(tasks), file=sys.stderr)
failures = 0
with futures.ThreadPoolExecutor(max_workers=workers) as executor:
    future_list = []

    for task in tasks:
        future = executor.submit(worker, task)
        future_list.append(future)
        try:
            r = future.result(timeout=0.8)
            print("INFO: Task %s returned %s" % (task, r), file=sys.stderr)
        except futures._base.TimeoutError:
            # that exception contains no other info than its name
            print("ERROR: TimeoutError while running task %s" % task, file=sys.stderr)
            failures += 1
            pass
        except Exception as e:
            print("ERROR: %s raised by task %s: %s" % (type(e).__name__, task, e), file=sys.stderr)
            failures += 1


if failures:
    sys.stderr.flush()
    print("ERROR: Finished with %s/%s task failures." % (failures ,len(tasks)), file=sys.stderr)
    sys.exit(66)