65 lines
1.8 KiB
Python
65 lines
1.8 KiB
Python
"Single-process in-memory cache backend."
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from django.core.cache.backends.base import BaseCache
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import time
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class CacheClass(BaseCache):
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def __init__(self, host, params):
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BaseCache.__init__(self, params)
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self._cache = {}
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self._expire_info = {}
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max_entries = params.get('max_entries', 300)
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try:
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self._max_entries = int(max_entries)
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except (ValueError, TypeError):
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self._max_entries = 300
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cull_frequency = params.get('cull_frequency', 3)
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try:
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self._cull_frequency = int(cull_frequency)
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except (ValueError, TypeError):
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self._cull_frequency = 3
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def get(self, key, default=None):
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now = time.time()
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exp = self._expire_info.get(key)
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if exp is None:
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return default
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elif exp < now:
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del self._cache[key]
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del self._expire_info[key]
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return default
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else:
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return self._cache[key]
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def set(self, key, value, timeout=None):
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if len(self._cache) >= self._max_entries:
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self._cull()
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if timeout is None:
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timeout = self.default_timeout
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self._cache[key] = value
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self._expire_info[key] = time.time() + timeout
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def delete(self, key):
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try:
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del self._cache[key]
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except KeyError:
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pass
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try:
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del self._expire_info[key]
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except KeyError:
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pass
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def has_key(self, key):
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return self._cache.has_key(key)
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def _cull(self):
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if self._cull_frequency == 0:
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self._cache.clear()
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self._expire_info.clear()
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else:
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doomed = [k for (i, k) in enumerate(self._cache) if i % self._cull_frequency == 0]
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for k in doomed:
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self.delete(k)
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