46 lines
1.0 KiB
Python
46 lines
1.0 KiB
Python
# coding: utf-8
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"""
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Caching function for pictures.
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"""
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from __future__ import absolute_import, print_function, unicode_literals
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import requests
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class MemoryCache(object):
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def __init__(self, on_miss):
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self.hits = 0
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self.misses = 0
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self.map = {}
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self.on_miss = on_miss
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def get(self, key):
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cached = self.map.get(key, None)
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if cached is not None:
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self.hits += 1
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return cached
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item = self.map[key] = self.on_miss(key)
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self.misses += 1
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return item
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def total(self):
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return self.hits + self.misses
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def hit_rate(self):
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assert self.total() > 0
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return 100 * self.hits // self.total()
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def miss_rate(self):
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assert self.total() > 0
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return 100 * self.misses // self.total()
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class ImageCache(MemoryCache):
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@staticmethod
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def retrieve_photo(url):
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return requests.get(url)
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def __init__(self):
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super(self.__class__, self).__init__(on_miss=ImageCache.retrieve_photo)
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