#!/usr/bin/python3
#
# Univention Portal
#
# Copyright 2020-2022 Univention GmbH
#
# https://www.univention.de/
#
# All rights reserved.
#
# The source code of this program is made available
# under the terms of the GNU Affero General Public License version 3
# (GNU AGPL V3) as published by the Free Software Foundation.
#
# Binary versions of this program provided by Univention to you as
# well as other copyrighted, protected or trademarked materials like
# Logos, graphics, fonts, specific documentations and configurations,
# cryptographic keys etc. are subject to a license agreement between
# you and Univention and not subject to the GNU AGPL V3.
#
# In the case you use this program under the terms of the GNU AGPL V3,
# the program is provided in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public
# License with the Debian GNU/Linux or Univention distribution in file
# /usr/share/common-licenses/AGPL-3; if not, see
# <https://www.gnu.org/licenses/>.
#
import json
import os
from copy import deepcopy
from six import with_metaclass
from univention.portal import Plugin
from univention.portal.log import get_logger
[docs]class Cache(with_metaclass(Plugin)):
"""
Base class for Caching in general
`get`: Gets the complete cache content.
`refresh`: Refreshes the cache. Gets a "reason" to decide if this is
really needed. The value "force" should be handled as if it is really
needed.
cache_file:
Filename where the content is stored
reloader:
Class that handles the actual refresh
"""
def __init__(self, cache_file, reloader=None):
self._cache_file = cache_file
self._reloader = reloader
self._cache = {}
self._loaded = False
[docs] def get_id(self):
try:
stat = os.stat(self._cache_file)
return str(stat.st_mtime)
except (EnvironmentError):
return ""
def _load(self):
get_logger("cache").info("loading cache file {}".format(self._cache_file))
try:
with open(self._cache_file) as fd:
self._cache = json.load(fd)
except (EnvironmentError, ValueError):
get_logger("cache").exception("Error loading {}".format(self._cache_file))
else:
self._loaded = True
[docs] def get(self):
if not self._loaded or self.refresh():
self._load()
return self._cache
[docs] def refresh(self, reason=None):
if self._reloader:
return self._reloader.refresh(reason=reason, content=self._cache)
[docs]class PortalFileCache(Cache):
"""
Specialized cache for portal data. The implementation does not differ
from that of a base cache, but it provides more specialized cache
access methods that it needs in order to work with the Portal class.
`get_user_links`
`get_entries`
`get_folders`
`get_portal`
`get_categories`
`get_menu_links`
"""
[docs] def get_user_links(self):
return deepcopy(self.get()["user_links"])
[docs] def get_entries(self):
return deepcopy(self.get()["entries"])
[docs] def get_folders(self):
return deepcopy(self.get()["folders"])
[docs] def get_portal(self):
return deepcopy(self.get()["portal"])
[docs] def get_categories(self):
return deepcopy(self.get()["categories"])
[docs]class GroupFileCache(Cache):
"""
Caching class for groups.
In fact it is just the same as the normal Cache and just here in case
we want to get smarter at some point.
"""
