58 lines
1.8 KiB
Python
58 lines
1.8 KiB
Python
# -*- coding: utf-8 -*-
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#
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# Copyright (C) 2014 eNovance Inc. All Rights Reserved.
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#
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# Licensed under the Apache License, Version 2.0 (the "License"); you may
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# not use this file except in compliance with the License. You may obtain
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# a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
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# License for the specific language governing permissions and limitations
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# under the License.
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import abc
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import six
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@six.add_metaclass(abc.ABCMeta)
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class Lock(object):
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def __init__(self, name):
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if not name:
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raise ValueError("Locks must be provided a name")
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self.name = name
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def __enter__(self):
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self.acquire()
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def __exit__(self, exc_type, exc_val, exc_tb):
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self.release()
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@abc.abstractmethod
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def release(self):
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"""Attempts to release the lock, returns true if released.
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The behavior of releasing a lock which was not acquired in the first
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place is undefined (it can range from harmless to releasing some other
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users lock)..
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:returns: returns true if released (false if not)
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:rtype: bool
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"""
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@abc.abstractmethod
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def acquire(self, blocking=True):
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"""Attempts to acquire the lock.
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:param blocking: If True, blocks until the lock is acquired. If False,
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returns right away. Otherwise, the value is used as a
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timeout value and the call returns maximum after this
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number of seonds.
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:returns: returns true if acquired (false if not)
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:rtype: bool
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"""
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