| |
| |
| |
|
|
| """ |
| The cache object API for implementing caches. The default is a thread |
| safe in-memory dictionary. |
| """ |
| from __future__ import annotations |
|
|
| from threading import Lock |
| from typing import IO, TYPE_CHECKING, MutableMapping |
|
|
| if TYPE_CHECKING: |
| from datetime import datetime |
|
|
|
|
| class BaseCache: |
| def get(self, key: str) -> bytes | None: |
| raise NotImplementedError() |
|
|
| def set( |
| self, key: str, value: bytes, expires: int | datetime | None = None |
| ) -> None: |
| raise NotImplementedError() |
|
|
| def delete(self, key: str) -> None: |
| raise NotImplementedError() |
|
|
| def close(self) -> None: |
| pass |
|
|
|
|
| class DictCache(BaseCache): |
| def __init__(self, init_dict: MutableMapping[str, bytes] | None = None) -> None: |
| self.lock = Lock() |
| self.data = init_dict or {} |
|
|
| def get(self, key: str) -> bytes | None: |
| return self.data.get(key, None) |
|
|
| def set( |
| self, key: str, value: bytes, expires: int | datetime | None = None |
| ) -> None: |
| with self.lock: |
| self.data.update({key: value}) |
|
|
| def delete(self, key: str) -> None: |
| 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: str, body: bytes) -> None: |
| raise NotImplementedError() |
|
|
| def get_body(self, key: str) -> IO[bytes] | None: |
| """ |
| Return the body as file-like object. |
| """ |
| raise NotImplementedError() |
|
|
