Cache sidebar with a simple caching API
We cache the sidebar once for every user, the downside is that once
the user meets new access criteria, their sidebar does not get
updated. This can be fixed by calling soc.cache.sidebar.flush() when
appropriate.
Patch by: Sverre Rabbelier
#!/usr/bin/python2.5
#
# Copyright 2008 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
from google.appengine.api import users
import soc.cache.base
def key(user):
"""Returns the memcache key for the user's sidebar
"""
return 'sidebar_for_%s' % repr(user)
def get():
"""Retrieves the sidebar for the specified user from the memcache
"""
user = users.get_current_user()
return memcache.get(key(user))
def put(sidebar):
"""Sets the sidebar for the specified user in the memcache
Args:
sidebar: the sidebar to be cached
"""
# Store sidebar for an hour since new programs might get added
# etc. etc.
retention = 60*60
user = users.get_current_user()
memcache.add(key(user), sidebar, retention)
def flush(user=None):
"""Removes the sidebar for the current user from the memcache
Args:
user: defaults to the current user if not set
"""
if not user:
user = users.get_current_user()
memcache.delete(key(user))
# define the cache function
cache = soc.cache.base.getCacher(get, put)