1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
|
# Copyright 2015, Google Inc.
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are
# met:
#
# * Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
# * Redistributions in binary form must reproduce the above
# copyright notice, this list of conditions and the following disclaimer
# in the documentation and/or other materials provided with the
# distribution.
# * Neither the name of Google Inc. nor the names of its
# contributors may be used to endorse or promote products derived from
# this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
"""A thread pool that logs exceptions raised by tasks executed within it."""
import functools
import logging
from concurrent import futures
def _wrap(behavior):
"""Wraps an arbitrary callable behavior in exception-logging."""
@functools.wraps(behavior)
def _wrapping(*args, **kwargs):
try:
return behavior(*args, **kwargs)
except Exception as e:
logging.exception('Unexpected exception from task run in logging pool!')
raise
return _wrapping
class _LoggingPool(object):
"""An exception-logging futures.ThreadPoolExecutor-compatible thread pool."""
def __init__(self, backing_pool):
self._backing_pool = backing_pool
def __enter__(self):
return self
def __exit__(self, exc_type, exc_val, exc_tb):
self._backing_pool.shutdown(wait=True)
def submit(self, fn, *args, **kwargs):
return self._backing_pool.submit(_wrap(fn), *args, **kwargs)
def map(self, func, *iterables, **kwargs):
return self._backing_pool.map(
_wrap(func), *iterables, timeout=kwargs.get('timeout', None))
def shutdown(self, wait=True):
self._backing_pool.shutdown(wait=wait)
def pool(max_workers):
"""Creates a thread pool that logs exceptions raised by the tasks within it.
Args:
max_workers: The maximum number of worker threads to allow the pool.
Returns:
A futures.ThreadPoolExecutor-compatible thread pool that logs exceptions
raised by the tasks executed within it.
"""
return _LoggingPool(futures.ThreadPoolExecutor(max_workers))
|