You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

60 lines
1.6 KiB

#
# Copyright 2021 Splunk Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
"""
Copyright (C) 2005-2019 Splunk Inc. All Rights Reserved.
Commonly used design partten for python user, includes:
- singleton (Decorator function used to build singleton)
"""
import warnings
from functools import wraps
def singleton(class_):
"""
Singleton decoorator function.
"""
warnings.warn(
"This function is deprecated. "
"Please see https://github.com/splunk/addonfactory-ta-library-python/issues/38",
DeprecationWarning,
stacklevel=2,
)
instances = {}
@wraps(class_)
def getinstance(*args, **kwargs):
if class_ not in instances:
instances[class_] = class_(*args, **kwargs)
return instances[class_]
return getinstance
class Singleton(type):
"""
Singleton meta class
"""
_instances = {}
def __call__(cls, *args, **kwargs):
if cls not in cls._instances:
cls._instances[cls] = super().__call__(*args, **kwargs)
print(cls)
return cls._instances[cls]