Fire-and-forget task (ARCH2021)

Key python.async.fire-and-forget-task · Severity warning · Category async

Leaving a coroutine or task as a bare expression statement without awaiting, assigning, or returning it loses exceptions and makes ordering undefined. The task runs unsupervised in the background and its failures vanish silently.

Incorrect

import asyncio

async def handle():
    asyncio.create_task(send_email())  # unawaited, errors are lost
    return "ok"

Correct

import asyncio

async def handle():
    task = asyncio.create_task(send_email())
    await task
    return "ok"

Fix

Await the created task, return it, or manage its lifetime and exceptions with a TaskGroup.