def reacquire(self) -> Awaitable[bool]:
"""
Resets a TTL of an already acquired lock back to a timeout value.
"""
if self.local.token is None:
raise LockError("Cannot reacquire an unlocked lock")
if self.timeout is None:
raise LockError("Cannot reacquire a lock with no timeout")
return self.do_reacquire()
def release(self) -> Awaitable[NoReturn]:
"""Releases the already acquired lock"""
expected_token = self.local.token
if expected_token is None:
raise LockError("Cannot release an unlocked lock")
self.local.token = None
return self.do_release(expected_token)
def extend(self,
additional_time: float,
replace_ttl: bool = False) -> Awaitable[bool]:
"""
Adds more time to an already acquired lock.
``additional_time`` can be specified as an integer or a float, both
representing the number of seconds to add.
``replace_ttl`` if False (the default), add `additional_time` to
the lock's existing ttl. If True, replace the lock's ttl with
`additional_time`.
"""
if self.local.token is None:
raise LockError("Cannot extend an unlocked lock")
if self.timeout is None:
raise LockError("Cannot extend a lock with no timeout")
return self.do_extend(additional_time, replace_ttl)
async def __aenter__(self):
# force blocking, as otherwise the user would have to check whether
# the lock was actually acquired or not.
if await self.acquire(blocking=True):
return self
raise LockError("Unable to acquire lock within the time specified")
async def __aenter__(self):
if await self.acquire():
return self
raise LockError("Unable to acquire lock within the time specified")