1# Copyright 2014 Google Inc. All Rights Reserved.
2#
3# Licensed under the Apache License, Version 2.0 (the "License");
4# you may not use this file except in compliance with the License.
5# You may obtain a copy of the License at
6#
7#      http://www.apache.org/licenses/LICENSE-2.0
8#
9# Unless required by applicable law or agreed to in writing, software
10# distributed under the License is distributed on an "AS IS" BASIS,
11# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12# See the License for the specific language governing permissions and
13# limitations under the License.
14
15"""Caching utility for the discovery document."""
16
17from __future__ import absolute_import
18
19import logging
20import datetime
21
22
23LOGGER = logging.getLogger(__name__)
24
25DISCOVERY_DOC_MAX_AGE = 60 * 60 * 24  # 1 day
26
27
28def autodetect():
29  """Detects an appropriate cache module and returns it.
30
31  Returns:
32    googleapiclient.discovery_cache.base.Cache, a cache object which
33    is auto detected, or None if no cache object is available.
34  """
35  try:
36    from google.appengine.api import memcache
37    from . import appengine_memcache
38    return appengine_memcache.cache
39  except Exception:
40    try:
41      from . import file_cache
42      return file_cache.cache
43    except Exception as e:
44      LOGGER.warning(e, exc_info=True)
45      return None
46