tiramisu/tiramisu/plugins/sqlite3/cache.py
2013-08-20 09:47:12 +02:00

82 lines
3.3 KiB
Python

# -*- coding: utf-8 -*-
"default plugin for cache: set it in a simple dictionary"
# Copyright (C) 2013 Team tiramisu (see AUTHORS for all contributors)
#
# 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
#
# ____________________________________________________________
from pickle import dumps, loads
import sqlite3
class Cache(object):
__slots__ = ('_conn', '_cursor')
key_is_path = True
def __init__(self, config_id, cache_type):
cache_table = 'CREATE TABLE IF NOT EXISTS cache_{0}(path text primary key, value text, time real)'.format(cache_type)
self._conn = sqlite3.connect(config_id + '.db')
self._conn.text_factory = str
self._cursor = self._conn.cursor()
self._cursor.execute(cache_table)
# value
def _sqlite_decode(self, value):
return loads(value)
def _sqlite_encode(self, value):
if isinstance(value, list):
value = list(value)
return dumps(value)
def setcache(self, cache_type, path, val, time):
convert_value = self._sqlite_encode(val)
self._cursor.execute("DELETE FROM cache_{0} WHERE path = ?".format(cache_type), (path,))
self._cursor.execute("INSERT INTO cache_{0}(path, value, time) VALUES (?, ?, ?)".format(cache_type),
(path, convert_value, time))
self._conn.commit()
def getcache(self, cache_type, path, exp):
self._cursor.execute("SELECT value FROM cache_{0} WHERE path = ? AND time >= ?".format(cache_type), (path, exp))
cached = self._cursor.fetchone()
if cached is None:
return False, None
else:
return True, self._sqlite_decode(cached[0])
def hascache(self, cache_type, path):
self._cursor.execute("SELECT value FROM cache_{0} WHERE path = ?".format(cache_type), (path,))
return self._cursor.fetchone() is not None
def reset_expired_cache(self, cache_type, exp):
self._cursor.execute("DELETE FROM cache_{0} WHERE time < ?".format(cache_type), (exp,))
self._conn.commit()
def reset_all_cache(self, cache_type):
self._cursor.execute("DELETE FROM cache_{0}".format(cache_type))
self._conn.commit()
def get_cached(self, cache_type, context):
"""return all values in a dictionary
example: {option1: ('value1', 'time1'), option2: ('value2', 'time2')}
"""
self._cursor.execute("SELECT * FROM cache_{0}".format(cache_type))
ret = {}
for path, value, time in self._cursor.fetchall():
opt = context.cfgimpl_get_description().impl_get_opt_by_path(path)
value = self._sqlite_decode(value)
ret[opt] = (value, time)
return ret