实操python3.6当中的异步IO（ asyncio） 协程

我们的自动化部署平台升级到django2+python3了，

并发方面的知识点，也跟进一下啦。

http://python.jobbole.com/87310/

这篇讲得挺入门的~~

实操一下。

import time
import asyncio
import functools

now = lambda : time.time()

async def do_some_work(x):
    print('Waiting: ', x)
    await asyncio.sleep(x)
    return 'Done after {}s'.format(x)
def callback(t, future):
    print('Callback: ', t, future.result())

start = now()

coroutine1 = do_some_work(1)
coroutine2 = do_some_work(2)
coroutine4 = do_some_work(4)


tasks = [
    asyncio.ensure_future(coroutine1),
    asyncio.ensure_future(coroutine2),
    asyncio.ensure_future(coroutine4),
    ]


loop =asyncio.get_event_loop()

for task in tasks:
    task.add_done_callback(functools.partial(callback, 2))

loop.run_until_complete(asyncio.wait(tasks))

for task in tasks:
    task.add_done_callback(functools.partial(callback, 2))
    print('Task return: {}'.format(task.result()))


print('TIME: ', now() - start)