Files
2023-06-01 14:57:15 +08:00

34 lines
1.1 KiB
Python

#!/usr/bin/env python3
# -*- coding:utf-8 -*-
#############################################################################
# Copyright (c) 2023 Huawei Technologies Co.,Ltd.
#
# openGauss is licensed under Mulan PSL v2.
# You can use this software according to the terms
# and conditions of the Mulan PSL v2.
# You may obtain a copy of Mulan PSL v2 at:
#
# http://license.coscl.org.cn/MulanPSL2
#
# THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS,
# WITHOUT WARRANTIES OF ANY KIND,
# EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
# MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
# See the Mulan PSL v2 for more details.
# ----------------------------------------------------------------------------
# Description : gs_upgradechk is a utility to check meta data in gaussdb after upgrade.
#############################################################################
"""
单例模式
"""
def singleton(cls):
_instance = {}
def inner():
if cls not in _instance:
_instance[cls] = cls()
return _instance.get(cls)
return inner