chrome/common/extensions/docs/server2/memcache_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 import logging
   6 import traceback
   7
   8 from appengine_wrappers import memcache
   9 from future import Future
  10 from object_store import ObjectStore
  11
  12
  13 class MemcacheObjectStore(ObjectStore):
  14   def __init__(self, namespace):
  15     self._namespace = namespace
  16
  17   def SetMulti(self, mapping):
  18     # Some files are too big to fit in memcache, and will throw a ValueError if
  19     # we try. That's caught below, but to avoid log spew as much as possible
  20     # (and to try to store as many things as possible, since this is Set*Multi*
  21     # after all, and there may be other things to store from |mapping|), delete
  22     # the paths which we know don't work.
  23     #
  24     # TODO(kalman): Store big things (like example zips) in blobstore so that
  25     # this doesn't happen.
  26     log_spewers = ('assets/remote-debugging/remote-debug-banner.ai',)
  27     for spewer in log_spewers:
  28       mapping.pop(spewer, None)
  29
  30     try:
  31       rpc = memcache.Client().set_multi_async(mapping,
  32                                               namespace=self._namespace)
  33       return Future(callback=rpc.get_result)
  34     except ValueError as e:
  35       logging.error('Caught error when memcache-ing keys %s: %s' %
  36                     (mapping.keys(), traceback.format_exc()))
  37       return Future(value=None)
  38
  39   def GetMulti(self, keys):
  40     rpc = memcache.Client().get_multi_async(keys, namespace=self._namespace)
  41     return Future(callback=rpc.get_result)
  42
  43   def DelMulti(self, keys):
  44     memcache.delete_multi(keys, namespace=self._namespace)