Files
fastapi-cache/fastapi_cache/backends/inmemory.py
Martijn Pieters d10f4af6d6 Import supported backends
This ensures that any syntax issues are caught early (by type checkers
and tests). Backends that are missing dependencies are skipped. By
importing, this exposed an issue where the redis type annotations
raised an exception, which has been fixed by using forward annotations.

To help avoid import dependency hell, the Backend ABC has been moved to
`fastapi_cache.types`. In the process, it has been made an actual ABC.
2023-05-14 17:02:30 +01:00

62 lines
1.6 KiB
Python

import time
from asyncio import Lock
from dataclasses import dataclass
from typing import Dict, Optional, Tuple
from fastapi_cache.types import Backend
@dataclass
class Value:
data: bytes
ttl_ts: int
class InMemoryBackend(Backend):
_store: Dict[str, Value] = {}
_lock = Lock()
@property
def _now(self) -> int:
return int(time.time())
def _get(self, key: str) -> Optional[Value]:
v = self._store.get(key)
if v:
if v.ttl_ts < self._now:
del self._store[key]
else:
return v
return None
async def get_with_ttl(self, key: str) -> Tuple[int, Optional[bytes]]:
async with self._lock:
v = self._get(key)
if v:
return v.ttl_ts - self._now, v.data
return 0, None
async def get(self, key: str) -> Optional[bytes]:
async with self._lock:
v = self._get(key)
if v:
return v.data
return None
async def set(self, key: str, value: bytes, expire: Optional[int] = None) -> None:
async with self._lock:
self._store[key] = Value(value, self._now + (expire or 0))
async def clear(self, namespace: Optional[str] = None, key: Optional[str] = None) -> int:
count = 0
if namespace:
keys = list(self._store.keys())
for key in keys:
if key.startswith(namespace):
del self._store[key]
count += 1
elif key:
del self._store[key]
count += 1
return count