team-3/src/c3nav/mapdata/utils/cache/local.py

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from collections import OrderedDict
from django.core.cache import cache
class NoneFromCache:
pass
class LocalCacheProxy:
# django cache, buffered using a LRU cache
# only usable for stuff that never changes, obviously
def __init__(self, maxsize=128):
self._maxsize = maxsize
self._items = OrderedDict()
def get(self, key, default=None):
print('get')
try:
# first check out cache
result = self._items[key]
except KeyError:
# not in our cache
result = cache.get(key, default=NoneFromCache)
if result is not NoneFromCache:
self._items[key] = result
self._prune()
else:
result = default
else:
self._items.move_to_end(key, last=True)
return result
def _prune(self):
# remove old items
while len(self._items) > self._maxsize:
self._items.pop(next(iter(self._items.keys())))
def set(self, key, value, expire):
cache.set(key, value, expire)
self._items[key] = value
self._prune()