42 lines
1.1 KiB
Python
42 lines
1.1 KiB
Python
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"""Simple async-safe TTL cache."""
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from __future__ import annotations
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import asyncio
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import time
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from typing import Any, Dict, Optional, Tuple
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class TTLCache:
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"""Thread/async-safe in-memory cache with per-key TTL."""
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def __init__(self) -> None:
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self._store: Dict[str, Tuple[Any, float]] = {}
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self._lock = asyncio.Lock()
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async def get(self, key: str) -> Optional[Any]:
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async with self._lock:
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entry = self._store.get(key)
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if entry is None:
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return None
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value, expires_at = entry
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if time.time() > expires_at:
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del self._store[key]
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return None
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return value
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async def set(self, key: str, value: Any, ttl: int) -> None:
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async with self._lock:
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self._store[key] = (value, time.time() + ttl)
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async def invalidate(self, key: str) -> None:
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async with self._lock:
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self._store.pop(key, None)
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async def clear(self) -> None:
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async with self._lock:
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self._store.clear()
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cache = TTLCache()
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