asyncio-compatible timeout context manager.
The context manager is useful in cases when you want to apply timeout
logic around block of code or in cases when
not suitable. Also it's much faster than
timeout doesn't create a new task.
timeout(delay, *, loop=None) call returns a context manager
that cancels a block on timeout expiring:
async with timeout(1.5): await inner()
inner()is executed faster than in
1.5seconds nothing happens.
inner()is cancelled internally by sending
asyncio.TimeoutErroris raised outside of context manager scope.
timeout parameter could be
None for skipping timeout functionality.
timeout_at(when) can be used for scheduling
at the absolute time:
loop = asyncio.get_event_loop() now = loop.time() async with timeout_at(now + 1.5): await inner()
Please note: it is not POSIX time but a time with undefined starting base, e.g. the time of the system power on.
Context manager has
.expired property for check if timeout happens
exactly in context manager:
async with timeout(1.5) as cm: await inner() print(cm.expired)
The property is
inner() execution is cancelled by
timeout context manager.
inner() call explicitly raises
The scheduled deadline time is available as
async with timeout(1.5) as cm: cm.deadline
Not finished yet timeout can be rescheduled by
async with timeout(1.5) as cm: cm.shift_by(1) # add another second on waiting cm.shift_to(loop.time() + 5) # reschedule to now+5 seconds
Rescheduling is forbidden if the timeout is expired or after exit from
$ pip install async-timeout
The library is Python 3 only!
Authors and License
The module is written by Andrew Svetlov.
It's Apache 2 licensed and freely available.