Async Error Swallowed (ARCH2169)

Key python.logging.async-error-swallowed · Severity warning · Category logging

Unawaited coroutines and fire-and-forget tasks let the exceptions inside them vanish silently. The task fails but it is never noticed or logged anywhere.

Incorrect

async def handle(req):
    asyncio.create_task(send_notification(req))
    return ok()

Correct

async def handle(req):
    task = asyncio.create_task(send_notification(req))
    task.add_done_callback(
        lambda t: t.exception() and logger.error("Notification failed", exc_info=t.exception())
    )
    return ok()

Fix

Await the task, or attach a done-callback that catches and logs the exception.