28 lines
982 B
Python
28 lines
982 B
Python
# Copyright 2016 Mirantis, Inc.
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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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class SingletonMeta(type):
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"""Metaclass for Singleton
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Main goals: not need to implement __new__ in singleton classes
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"""
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_instances = {}
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def __call__(cls, *args, **kwargs):
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if cls not in cls._instances:
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cls._instances[cls] = super(
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SingletonMeta, cls).__call__(*args, **kwargs)
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return cls._instances[cls]
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