Python asyncio: how to cleanly handle sighandlers and close all pending tasks

python_shutdown_asyncio.py

#!/usr/bin/env python3.6

import asyncio
import signal


async def taskX(task_name, loop):
    while True:
        try:
            # simulate long running task
            print("Task {} rnning...".format(task_name))
            await asyncio.sleep(10, loop=loop)
        except asyncio.CancelledError:
            print("Task {} cancelled. Returning".format(task_name))
            return

async def signal_handler(signame, loop):
    # Call ny tasks that provide `stop` method
    # await taskx.stop()
    for task in asyncio.Task.all_tasks(loop=loop):
        # cancel all tasks other than this signal_handler
        if task is not asyncio.Task.current_task():
            task.cancel()
    await asyncio.sleep(5, loop=loop);  # or however you think is reanable to wait.
    loop.stop()


loop = asyncio.get_event_loop()
for i in range(7):
    asyncio.ensure_future(taskX("task_" + str(i), loop))

# Add signal handlers
for signame in ['SIGTERM', 'SIGINT', 'SIGHUP']:
    loop.add_signal_handler(getattr(signal, signame),
                            lambda: asyncio.ensure_future(signal_handler(signame, loop)))

try:
    loop.run_forever()
finally:
    loop.close()