Skip to content

academy.event

wait_event_async async 

wait_event_async(
    *events: Event, timeout: float | None = None
) -> Event

Wait for the first async event to be set.

Parameters:

  • events (Event, default: () ) –

    One or more events to wait on.

  • timeout (float | None, default: None ) –

    Maximum number of seconds to wait for an event to finish.

Returns:

  • Event –

    The first event to finish.

Raises:

  • TimeoutError –

    If no event finished within timeout seconds.

Source code in academy/event.py 
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
async def wait_event_async(
    *events: asyncio.Event,
    timeout: float | None = None,
) -> asyncio.Event:
    """Wait for the first async event to be set.

    Args:
        events: One or more events to wait on.
        timeout: Maximum number of seconds to wait for an event to finish.

    Returns:
        The first event to finish.

    Raises:
        TimeoutError: If no event finished within `timeout` seconds.
    """
    tasks = {
        asyncio.create_task(event.wait(), name=f'or-event-waiter-{i}'): event
        for i, event in enumerate(events)
    }
    done, pending = await asyncio.wait(
        tasks.keys(),
        timeout=timeout,
        return_when=asyncio.FIRST_COMPLETED,
    )
    for task in pending:
        task.cancel()
        with contextlib.suppress(asyncio.CancelledError):
            await task

    if len(done) == 0:
        raise TimeoutError(f'No events were set within {timeout} seconds.')

    return tasks[done.pop()]