asyncio Event(事件)

task 是协程和 Future 的桥梁。

# coding=utf-8
import asyncio
import functools


def set_event (event):
    print('在回调中设置事件')
    event.set()


async def test (name, event):
    print('\t{} waiting for event'.format(name))
    await event.wait()
    print('\t{} triggered'.format(name))


async def main (loop):
    event = asyncio.Event()
    print('事件开始状态：{}'.format(event.is_set()))
    loop.call_later(0.1, functools.partial(set_event, event))
    await asyncio.wait([test('e1', event), test('e2', event)])
    print('事件结束状态：{}'.format(event.is_set()))
    event.clear()


if __name__ == '__main__':
    loop = asyncio.get_event_loop()
    try:  # -------------------------------
        loop.run_until_complete(main(loop))
    finally:
        loop.close()

输出：

事件开始状态：False
	e2 waiting for event
	e1 waiting for event
在回调中设置事件
	e2 triggered
	e1 triggered
事件结束状态：True