34 lines
1.1 KiB
Python
34 lines
1.1 KiB
Python
# Copyright (c) 2018 OpenStack Foundation.
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# 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 functools
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class LazyProxy(object):
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def __init__(self, klass, *args, **kwargs):
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self.klass = klass
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self.args = args
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self.kwargs = kwargs
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self.instance = None
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def __getattr__(self, name):
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return functools.partial(self.__run_method, name)
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def __run_method(self, __name, *args, **kwargs):
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if self.instance is None:
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self.instance = self.klass(*self.args, **self.kwargs)
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return getattr(self.instance, __name)(*args, **kwargs)
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