Python 3.7+Async programmingfunction

asyncio.all_tasks()

introspection

Returns the set of not-yet-finished tasks of the running event loop, including the task that made the call.

Syntax

asyncio.all_tasks(loop=None)

The set includes the calling task itself (main under asyncio.run), so "wait for all the others" is written as all_tasks() - {current_task()}; otherwise gather would wait for itself forever. Finished tasks are not reported. Without a running loop the function raises RuntimeError; the old Task.all_tasks() method was removed in 3.9.

Examples

import asyncio
async def job():
    await asyncio.sleep(0.01)
async def main():
    tasks = [asyncio.create_task(job()) for _ in range(2)]
    print(len(asyncio.all_tasks()))  # → 3 — две job и сама main
    others = asyncio.all_tasks() - {asyncio.current_task()}
    await asyncio.gather(*others)
    print(len(asyncio.all_tasks()))  # → 1
asyncio.run(main())

import asyncio
try:
    asyncio.all_tasks()
except RuntimeError as e:
    print(e)  # → no running event loop

See also

Common errors

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