| Attila Fazekas | 3e1b674 | 2013-01-28 16:30:35 +0100 | [diff] [blame] | 1 | # vim: tabstop=4 shiftwidth=4 softtabstop=4 |
| 2 | |
| 3 | # Copyright 2012 OpenStack, LLC |
| 4 | # All Rights Reserved. |
| 5 | # |
| 6 | # Licensed under the Apache License, Version 2.0 (the "License"); you may |
| 7 | # not use this file except in compliance with the License. You may obtain |
| 8 | # a copy of the License at |
| 9 | # |
| 10 | # http://www.apache.org/licenses/LICENSE-2.0 |
| 11 | # |
| 12 | # Unless required by applicable law or agreed to in writing, software |
| 13 | # distributed under the License is distributed on an "AS IS" BASIS, WITHOUT |
| 14 | # WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the |
| 15 | # License for the specific language governing permissions and limitations |
| 16 | # under the License. |
| 17 | |
| 18 | |
| 19 | def singleton(cls): |
| 20 | """Simple wrapper for classes that should only have a single instance.""" |
| 21 | instances = {} |
| 22 | |
| 23 | def getinstance(): |
| 24 | if cls not in instances: |
| 25 | instances[cls] = cls() |
| 26 | return instances[cls] |
| 27 | return getinstance |