One bad job shouldn't take down the whole batch. If a job raises, capture the exception on its future and keep going, other jobs still run, and the error surfaces only when someone calls that future's result().
Update run(): wrap each job call in try/except and route a raised exception to fut.set_exception(...) instead of letting it escape.
from collections import deque
class Future:
def __init__(self):
self._done = False
self._result = None
self._exc = None
def set_result(self, value):
self._result = value
self._done = True
def set_exception(self, exc):
self._exc = exc
self._done = True
def done(self):
return self._done
def result(self):
if not self._done:
raise RuntimeError("future is not done")
if self._exc is not None:
raise self._exc
return self._result
class ThreadPool:
def __init__(self, num_workers):
self.num_workers = num_workers
self._queue = deque()
def submit(self, fn, *args, **kwargs):
fut = Future()
self._queue.append((fut, fn, args, kwargs))
return fut
def run(self):
"""Run all jobs; a job that raises fails only its own future."""
while self._queue:
fut, fn, args, kwargs = self._queue.popleft()
# TODO: wrap the call in try/except:
# try: fut.set_result(fn(*args, **kwargs))
# except Exception as e: fut.set_exception(e)
pass
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One bad job shouldn't take down the whole batch. If a job raises, capture the exception on its future and keep going, other jobs still run, and the error surfaces only when someone calls that future's result().
Update run(): wrap each job call in try/except and route a raised exception to fut.set_exception(...) instead of letting it escape.
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