35 lines
1018 B
Python
35 lines
1018 B
Python
"""Redis 分布式锁（SET NX EX）。"""
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import secrets
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import time
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import redis.asyncio as aioredis
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from app.config import settings
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class Lock:
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def __init__(self, redis: aioredis.Redis, name: str, timeout: int = settings.lock_timeout):
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self.redis = redis
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self.name = name
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self.timeout = timeout
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self._token = secrets.token_hex(8)
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async def acquire(self) -> bool:
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ok = await self.redis.set(self.name, self._token, nx=True, ex=self.timeout)
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return bool(ok)
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async def release(self) -> None:
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# 仅在持有相同 token 时释放，避免误删他人锁
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val = await self.redis.get(self.name)
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if val == self._token:
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await self.redis.delete(self.name)
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async def guarded(self, fn):
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"""上下文封装：获取锁执行，释放锁。"""
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if not await self.acquire():
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return False
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try:
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await fn()
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return True
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finally:
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await self.release() |