41 lines
1.1 KiB
Python
41 lines
1.1 KiB
Python
from threading import RLock
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class AvCache:
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"""
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Store a cache of avatar images we've already downloaded.
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This cache will be accessed by a number of threads, so it includes
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a lock as well.
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"""
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class __impl:
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""" Implementation of the singleton interface """
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def __init__(self):
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self.lock = RLock()
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self.map = {}
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# storage for the instance reference
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__instance = None
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def __init__(self):
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""" Create singleton instance """
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# Check whether we already have an instance
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if AvCache.__instance is None:
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# Create and remember instance
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AvCache.__instance = AvCache.__impl()
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# Store instance reference as the only member in the handle
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self.__dict__['_AvCache__instance'] = AvCache.__instance
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def __getattr__(self, attr):
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""" Delegate access to implementation """
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return getattr(self.__instance, attr)
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def __setattr__(self, attr, value):
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""" Delegate access to implementation """
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return setattr(self.__instance, attr, value)
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# end class AvCache
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