api请求的初学者异步/等待问题

Question

我想加快一些 API 请求...为此，我试图弄清楚如何做并复制一些运行的代码，但是当我尝试自己的代码时，它不再是异步的。也许有人发现失败？

复制代码（从计算器中猜测）：

#!/usr/bin/env python3

import asyncio

@asyncio.coroutine

def func_normal():

    print('A')

    yield from asyncio.sleep(5)

    print('B')

    return 'saad'

@asyncio.coroutine

def func_infinite():

    for i in range(10):

        print("--%d" % i)

    return 'saad2'

loop = asyncio.get_event_loop()

tasks = func_normal(), func_infinite()

a, b = loop.run_until_complete(asyncio.gather(*tasks))

print("func_normal()={a}, func_infinite()={b}".format(**vars()))

loop.close()

我的“自己的”代码（最后我需要返回一个列表并合并所有函数的结果）：

import asyncio

import time

@asyncio.coroutine

def say_after(start,count,say,yep=True):

    retl = []

    if yep:

        time.sleep(5)

    for x in range(start,count):

        retl.append(x)

        print(say)

    return retl

def main():

    print(f"started at {time.strftime('%X')}")

        

    loop = asyncio.get_event_loop()

    tasks = say_after(10,20,"a"), say_after(20,30,"b",False)

    a, b = loop.run_until_complete(asyncio.gather(*tasks))

    print("func_normal()={a}, func_infinite()={b}".format(**vars()))

    loop.close()

    c =  a + b

    #print(c)

    print(f"finished at {time.strftime('%X')}")

main()

或者我完全错了，应该用多线程解决这个问题？对于返回我需要合并的列表的 API 请求，最好的方法是什么？

Answer 1

为每个需要改进的部分添加了评论。删除了一些简单的代码。事实上，我没有发现 using range()wrapped in coroutine 和使用async def, 可能值得更重的操作有任何性能提升。import asyncioimport time# @asyncio.coroutine IS DEPRECATED since python [e-mail] say_after(wait=True):    result = []    if wait:        print("I'm sleeping!")        time.sleep(5)        print("'morning!")        # This BLOCKs thread, but release GIL so other thread can run.        # But asyncio runs in ONE thread, so this still harms simultaneity.    # normal for is BLOCKING operation.    for i in range(5):        result.append(i)        print(i, end='')    print()    return resultdef main():    start = time.time()    # Loop argument will be DEPRECATED from python 3.10    # Make main() as coroutine, then use asyncio.run(main()).    # It will be in asyncio Event loop, without explicitly passing Loop.    loop = asyncio.get_event_loop()    tasks = say_after(), say_after(False)    # As we will use asyncio.run(main()) from now on, this should be await-ed.    a, b = loop.run_until_complete(asyncio.gather(*tasks))    print(f"Took {time.time() - start:5f}")    loop.close()main()更好的方法：import asyncioimport timeasync def say_after(wait=True):    result = []    if wait:        print("I'm sleeping!")        await asyncio.sleep(2)  # 'await' a coroutine version of it instead.        print("'morning!")    # wrap iterator in generator - or coroutine    async def asynchronous_range(end):        for _i in range(end):            yield _i    # use it with async for    async for i in asynchronous_range(5):        result.append(i)        print(i, end='')    print()    return resultasync def main():    start = time.time()    tasks = say_after(), say_after(False)    a, b = await asyncio.gather(*tasks)    print(f"Took {time.time() - start:5f}")asyncio.run(main())结果你的代码：DeprecationWarning: "@coroutine" decorator is deprecated since Python 3.8, use "async def" instead  def say_after(wait=True):I'm sleeping!'morning!0123401234Took 5.003802更好的异步代码：I'm sleeping!01234'morning!01234Took 2.013863请注意，固定代码现在在其他任务休眠时完成其工作。