| # SPDX-FileCopyrightText: 2015 Eric Larson |
| # |
| # SPDX-License-Identifier: Apache-2.0 |
| |
| """ |
| The cache object API for implementing caches. The default is a thread |
| safe in-memory dictionary. |
| """ |
| from threading import Lock |
| |
| |
| class BaseCache(object): |
| |
| def get(self, key): |
| raise NotImplementedError() |
| |
| def set(self, key, value, expires=None): |
| raise NotImplementedError() |
| |
| def delete(self, key): |
| raise NotImplementedError() |
| |
| def close(self): |
| pass |
| |
| |
| class DictCache(BaseCache): |
| |
| def __init__(self, init_dict=None): |
| self.lock = Lock() |
| self.data = init_dict or {} |
| |
| def get(self, key): |
| return self.data.get(key, None) |
| |
| def set(self, key, value, expires=None): |
| with self.lock: |
| self.data.update({key: value}) |
| |
| def delete(self, key): |
| with self.lock: |
| if key in self.data: |
| self.data.pop(key) |
| |
| |
| class SeparateBodyBaseCache(BaseCache): |
| """ |
| In this variant, the body is not stored mixed in with the metadata, but is |
| passed in (as a bytes-like object) in a separate call to ``set_body()``. |
| |
| That is, the expected interaction pattern is:: |
| |
| cache.set(key, serialized_metadata) |
| cache.set_body(key) |
| |
| Similarly, the body should be loaded separately via ``get_body()``. |
| """ |
| def set_body(self, key, body): |
| raise NotImplementedError() |
| |
| def get_body(self, key): |
| """ |
| Return the body as file-like object. |
| """ |
| raise NotImplementedError() |