app/soc/cache/sidebar.py
author Sverre Rabbelier <sverre@rabbelier.nl>
Fri, 15 May 2009 23:05:13 +0200
changeset 2319 3eee2308f1dd
parent 1600 0aa3de1b2acc
child 2365 a66e1dd8ced7
permissions -rw-r--r--
Do not rely on notifiction module being imported This has worked so far mostly by accident, but it turned out to be brittle while writing tests. This makes sure that the notification module is always imported before use.

#!/usr/bin/python2.5
#
# Copyright 2009 the Melange authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#   http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

"""Module contains sidebar memcaching functions.
"""

__authors__ = [
    '"Sverre Rabbelier" <sverre@rabbelier.nl>',
  ]


from google.appengine.api import memcache

import soc.cache.base
import soc.cache.rights
import soc.logic.accounts


def key(id):
  """Returns the memcache key for the user's sidebar.
  """

  return 'sidebar_for_%s' % repr(id)


def get(id, *args, **kwargs):
  """Retrieves the sidebar for the specified user from the memcache.
  """

  memcache_key = key(id)
  return memcache.get(memcache_key), memcache_key


def put(sidebar, memcache_key, *args, **kwargs):
  """Sets the sidebar for the specified user in the memcache.

  Args:
    sidebar: the sidebar to be cached
  """

  # Store sidebar for just three minutes to force a refresh every so often
  retention = 3*60

  memcache.add(memcache_key, sidebar, retention)


def flush(id=None):
  """Removes the sidebar for the current user from the memcache.

  Also calls soc.cache.rights.flush for the specified user.

  Args:
    id: defaults to the current account if not set
  """

  if not id:
    id = soc.logic.accounts.getCurrentAccount()

  memcache_key = key(id)
  memcache.delete(memcache_key)
  soc.cache.rights.flush(id)


# define the cache function
cache = soc.cache.base.getCacher(get, put)