ScoDoc/app/scodoc/sco_cache.py

82 lines
2.3 KiB
Python

# -*- mode: python -*-
# -*- coding: utf-8 -*-
##############################################################################
#
# Gestion scolarite IUT
#
# Copyright (c) 1999 - 2021 Emmanuel Viennet. All rights reserved.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed 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 General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
#
# Emmanuel Viennet emmanuel.viennet@viennet.net
#
##############################################################################
"""Cache simple par etudiant
"""
import time
# Cache data
class simpleCache(object):
def __init__(self):
self.cache = {}
self.inval_cache() # >
def inval_cache(self, key=None): # >
if key:
if key in self.cache:
del self.cache[key]
else:
# clear all entries
self.cache = {} # key : data
def set(self, key, data):
self.cache[key] = data
def get(self, key):
"""returns None if not in cache"""
return self.cache.get(key, None)
class expiringCache(simpleCache):
"""A simple cache wich cache data for a most "duration" seconds.
This is used for users (which may be updated from external
information systems)
"""
def __init__(self, max_validity=60):
simpleCache.__init__(self)
self.max_validity = max_validity
def set(self, key, data):
simpleCache.set(self, key, (data, time.time()))
def get(self, key):
info = simpleCache.get(self, key)
if info:
data, t = info
if time.time() - t < self.max_validity:
return data
else:
# expired
self.inval_cache(key) # >
return None
else:
return None # not in cache