chrome/common/extensions/docs/server2/object_store.py

   1 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 # Use of this source code is governed by a BSD-style license that can be
   3 # found in the LICENSE file.
   4
   5 from future import Future
   6
   7
   8 class ObjectStore(object):
   9   '''A class for caching picklable objects.
  10   '''
  11   def Get(self, key):
  12     '''Gets a |Future| with the value of |key| in the object store, or None
  13     if |key| is not in the object store.
  14     '''
  15     return self.GetMulti((key,)).Then(lambda keys: keys.get(key))
  16
  17   def GetMulti(self, keys):
  18     '''Gets a |Future| with values mapped to |keys| from the object store, with
  19     any keys not in the object store omitted.
  20     '''
  21     raise NotImplementedError(self.__class__)
  22
  23   def Set(self, key, value):
  24     '''Sets key -> value in the object store. Returns a |Future| which is
  25     resolved once the key's new value has been stored.
  26     '''
  27     return self.SetMulti({ key: value })
  28
  29   def SetMulti(self, items):
  30     '''Atomically sets the mapping of keys to values in the object store.
  31     Returns a |Future| which is resolved once the new mapping has been stored.
  32     '''
  33     raise NotImplementedError(self.__class__)
  34
  35   def Del(self, key):
  36     '''Deletes a key from the object store.
  37     '''
  38     self.DelMulti([key])
  39
  40   def DelMulti(self, keys):
  41     '''Deletes |keys| from the object store.
  42     '''
  43     raise NotImplementedError(self.__class__)