#!/usr/bin/python3
# -*- coding: utf-8 -*-
#
# Univention S4 Connector
# LockingDB
#
# Copyright 2014-2022 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/>.
from __future__ import print_function
import univention.debug2 as ud
import sqlite3
[docs]class LockingDB(object):
"""
A local database which includes the list of objects
which are currently locked. That means the
synchronisation of these objects has not been finished.
https://forge.univention.org/bugzilla/show_bug.cgi?id=35391
"""
def __init__(self, filename):
self.filename = filename
self._dbcon = sqlite3.connect(self.filename)
self.s4cache = {}
self.__create_tables()
[docs] def lock_ucs(self, uuid):
if not uuid:
return None
# The SQLite python module should do the escaping, that's
# the reason why we use the tuple ? syntax.
# I've chosen the str call because I want to make sure
# that we use the same SQL value as before switching
# to the tuple ? syntax
sql_commands = [
("INSERT INTO UCS_LOCK(uuid) VALUES(?);", (str(uuid),))
]
self.__execute_sql_commands(sql_commands, fetch_result=False)
[docs] def unlock_ucs(self, uuid):
if not uuid:
return None
sql_commands = [
("DELETE FROM UCS_LOCK WHERE uuid = ?;", (str(uuid),))
]
self.__execute_sql_commands(sql_commands, fetch_result=False)
[docs] def lock_s4(self, guid):
if not guid:
return None
sql_commands = [
("INSERT INTO S4_LOCK(guid) VALUES(?);", (str(guid),))
]
self.__execute_sql_commands(sql_commands, fetch_result=False)
[docs] def unlock_s4(self, guid):
if not guid:
return None
sql_commands = [
("DELETE FROM S4_LOCK WHERE guid = ?;", (str(guid),))
]
self.__execute_sql_commands(sql_commands, fetch_result=False)
[docs] def is_ucs_locked(self, uuid):
if not uuid:
return False
sql_commands = [
("SELECT id FROM UCS_LOCK WHERE uuid=?;", (str(uuid),))
]
rows = self.__execute_sql_commands(sql_commands, fetch_result=True)
if rows:
return True
return False
[docs] def is_s4_locked(self, guid):
if not guid:
return False
sql_commands = [
("SELECT id FROM S4_LOCK WHERE guid=?;", (str(guid),))
]
rows = self.__execute_sql_commands(sql_commands, fetch_result=True)
if rows:
return True
return False
def __create_tables(self):
sql_commands = [
"CREATE TABLE IF NOT EXISTS S4_LOCK (id INTEGER PRIMARY KEY, guid TEXT);",
"CREATE TABLE IF NOT EXISTS UCS_LOCK (id INTEGER PRIMARY KEY, uuid TEXT);",
"CREATE INDEX IF NOT EXISTS s4_lock_guid ON s4_lock(guid);",
"CREATE INDEX IF NOT EXISTS ucs_lock_uuid ON ucs_lock(uuid);",
]
self.__execute_sql_commands(sql_commands, fetch_result=False)
def __execute_sql_commands(self, sql_commands, fetch_result=False):
for i in [1, 2]:
try:
cur = self._dbcon.cursor()
for sql_command in sql_commands:
if isinstance(sql_command, tuple):
ud.debug(ud.LDAP, ud.ALL, "LockingDB: Execute SQL command: %r, %r" % (sql_command[0], sql_command[1]))
cur.execute(sql_command[0], sql_command[1])
else:
ud.debug(ud.LDAP, ud.ALL, "LockingDB: Execute SQL command: %r" % (sql_command,))
cur.execute(sql_command)
self._dbcon.commit()
if fetch_result:
rows = cur.fetchall()
cur.close()
if fetch_result:
ud.debug(ud.LDAP, ud.ALL, "LockingDB: Return SQL result: %r" % (rows,))
return rows
return None
except sqlite3.Error as exp:
ud.debug(ud.LDAP, ud.WARN, "LockingDB: sqlite: %r. SQL command was: %r" % (exp, sql_commands))
if self._dbcon:
self._dbcon.close()
self._dbcon = sqlite3.connect(self.filename)
if __name__ == '__main__':
import random
print('Starting LockingDB test example ')
lock = LockingDB('lock.sqlite')
uuid1 = random.random()
guid1 = random.random()
if lock.is_s4_locked(guid1):
print('E: guid1 is locked for S4')
if lock.is_s4_locked(uuid1):
print('E: uuid1 is locked for S4')
if lock.is_ucs_locked(guid1):
print('E: guid1 is locked for UCS')
if lock.is_ucs_locked(uuid1):
print('E: uuid1 is locked for UCS')
lock.lock_s4(guid1)
if not lock.is_s4_locked(guid1):
print('E: guid1 is not locked for S4')
if lock.is_s4_locked(uuid1):
print('E: uuid1 is locked for S4')
if lock.is_ucs_locked(guid1):
print('E: guid1 is locked for UCS')
if lock.is_ucs_locked(uuid1):
print('E: uuid1 is locked for UCS')
lock.unlock_s4(guid1)
if lock.is_s4_locked(guid1):
print('E: guid1 is locked for S4')
if lock.is_s4_locked(uuid1):
print('E: uuid1 is locked for S4')
if lock.is_ucs_locked(guid1):
print('E: guid1 is locked for UCS')
if lock.is_ucs_locked(uuid1):
print('E: uuid1 is locked for UCS')
lock.lock_ucs(uuid1)
lock.lock_ucs(uuid1)
lock.lock_ucs(uuid1)
lock.lock_ucs(uuid1)
lock.lock_ucs(uuid1)
if lock.is_s4_locked(guid1):
print('E: guid1 is locked for S4')
if lock.is_s4_locked(uuid1):
print('E: uuid1 is locked for S4')
if lock.is_ucs_locked(guid1):
print('E: guid1 is locked for UCS')
if not lock.is_ucs_locked(uuid1):
print('E: uuid1 is not locked for UCS')
lock.unlock_ucs(uuid1)
if lock.is_s4_locked(guid1):
print('E: guid1 is locked for S4')
if lock.is_s4_locked(uuid1):
print('E: uuid1 is locked for S4')
if lock.is_ucs_locked(guid1):
print('E: guid1 is locked for UCS')
if lock.is_ucs_locked(uuid1):
print('E: uuid1 is locked for UCS')
print('done')
