67 lines
1.9 KiB
Python
67 lines
1.9 KiB
Python
# co-gahusb/app/locks.py
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from redis.exceptions import WatchError
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LOCK_PREFIX = "co:lock:"
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async def acquire_lock(r, resource, role, ttl_sec=300):
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key = LOCK_PREFIX + resource
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ok = await r.set(key, role, nx=True, ex=ttl_sec)
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if ok:
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return {"acquired": True}
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held_by = await r.get(key)
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ttl = await r.ttl(key)
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return {"acquired": False, "held_by": held_by, "ttl_remaining": max(ttl, 0)}
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async def release_lock(r, resource, role):
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key = LOCK_PREFIX + resource
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async with r.pipeline() as pipe:
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while True:
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try:
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await pipe.watch(key)
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owner = await pipe.get(key)
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if owner != role:
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await pipe.unwatch()
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return {"released": False, "held_by": owner}
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pipe.multi()
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pipe.delete(key)
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await pipe.execute()
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return {"released": True}
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except WatchError:
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continue
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async def heartbeat_lock(r, resource, role, ttl_sec=300):
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key = LOCK_PREFIX + resource
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async with r.pipeline() as pipe:
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while True:
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try:
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await pipe.watch(key)
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owner = await pipe.get(key)
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if owner != role:
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await pipe.unwatch()
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return {"renewed": False, "held_by": owner}
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pipe.multi()
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pipe.expire(key, ttl_sec)
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await pipe.execute()
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return {"renewed": True}
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except WatchError:
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continue
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async def list_locks(r):
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keys = await r.keys(LOCK_PREFIX + "*")
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out = []
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for key in keys:
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held_by = await r.get(key)
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if held_by is None:
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continue
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ttl = await r.ttl(key)
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out.append({
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"resource": key[len(LOCK_PREFIX):],
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"held_by": held_by,
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"ttl_remaining": max(ttl, 0),
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})
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return {"locks": out}
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