seafile_ynh/sources/seafile-server-3.1.1/seahub/thirdpart/Djblets-0.6.14.dev-py2.6.egg/djblets/util/contextmanagers.py
Elie 0f063400be Add sources
Former-commit-id: 2e47976ec5
2014-08-06 22:42:37 -04:00

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Python

#
# misc.py -- Miscellaneous utilities.
#
# Copyright (c) 2011 Beanbag, Inc.
# Copyright (c) 2011 Mike Conley
#
# Permission is hereby granted, free of charge, to any person obtaining
# a copy of this software and associated documentation files (the
# "Software"), to deal in the Software without restriction, including
# without limitation the rights to use, copy, modify, merge, publish,
# distribute, sublicense, and/or sell copies of the Software, and to
# permit persons to whom the Software is furnished to do so, subject to
# the following conditions:
#
# The above copyright notice and this permission notice shall be included
# in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
# IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
# CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
# TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
# SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
#
from contextlib import contextmanager
import logging
@contextmanager
def controlled_subprocess(process_name, process):
"""
A context manager for a subprocess that guarantees that a process
is terminated, even if exceptions are thrown while using it.
The process_name argument is used for logging when the process goes
down fighting. The process argument is a process returned by
subprocess.Popen.
Example usage:
process = subprocess.Popen(['patch', '-o', newfile, oldfile])
with controlled_subprocess("patch", process) as p:
# ... do things with the process p
Once outside the with block, you can rest assured that the subprocess
is no longer running.
"""
caught_exception = None
try:
yield process
except Exception, e:
caught_exception = e
# If we haven't gotten a returncode at this point, we assume the
# process is blocked. Let's kill it.
if process.returncode is None and process.poll() is None:
logging.warning(_("The process '%s' with PID '%s' did not exit " +
"cleanly and will be killed automatically.") %
(process_name, process.pid))
process.kill()
# Now that we've killed the process, we'll grab the return code,
# in order to clear the zombie.
process.wait()
# If we caught an exception earlier, re-raise it.
if caught_exception:
raise caught_exception