通过协程维持执行N个任务版本二

• aysnc_run.py

# -*- coding: utf-8 -*-

import asyncio
import functools
import os
import signal

batch_task_num = 10
aio_task_q = asyncio.Queue(maxsize=batch_task_num)
aio_running_q = asyncio.Queue(maxsize=batch_task_num)
produce_finish_event = asyncio.Event()


async def produce_tasks():
    for i in range(30):
        await aio_task_q.put(i)
        print("push", i)

    produce_finish_event.set()


def ask_exit(signame, loop):
    print("got signal %s: exit" % signame)
    loop.stop()


async def handle_task(task):
    print("running", task)
    await asyncio.sleep(task)
    print("end", task)
    await aio_running_q.get()


async def consume_tasks(loop):
    tasks = []
    while not aio_task_q.empty() or not produce_finish_event.is_set():
        await aio_running_q.put(True)
        task = await aio_task_q.get()
        tasks.append(loop.create_task(handle_task(task)))

    await asyncio.wait(tasks)
    loop.stop()


def main():
    loop = asyncio.get_event_loop()

    # for signame in {"SIGINT", "SIGTERM", "SIGQUIT"}:
    #     loop.add_signal_handler(
    #         getattr(signal, signame),
    #         functools.partial(ask_exit, signame, loop))

    loop.create_task(produce_tasks())
    loop.create_task(consume_tasks(loop))
    loop.run_forever()


if __name__ == "__main__":
    print("Event loop running, press Ctrl+C to interrupt.")
    print(f"pid {os.getpid()}: send SIGINT or SIGTERM to exit.")
    main()

• 实现原理
  • 该函数利用asycio模块中的队列以及事件实现N个任务同时执行（抽水式）
  • 不同之处：该版本利用了队列维持N个任务同时执行
  • 通过asycio事件确认是否完成生产者是否生产完毕