如何在Python中将同步转换为异步

我的代码可以很好地获取n到q范围内的数据，但是当我想要处理大范围（1-100000）时，它太慢了。我的代码需要3-4秒来完成每个post请求。所以我想加快速度，下面是我的代码：

import requests
from tqdm import tqdm

url = "https://www.example.com/info/item"
headers = {
    'Content-Type': "application/x-www-form-urlencoded",
    'Access-Control-Allow-Origin': "*",
    'Accept-Encoding': "gzip, deflate",
    'Accept-Language': "en-US",
    }

n = 1
q = 50
sum = 0
for i in tqdm(range(n,q)):
    payload = "item_id={}".format(i+1)
    response = requests.request("POST", url, data=payload, headers=headers)
    print(response.text)
    sum = sum + i

以上代码执行所有50个请求需要>150秒

---

这就是为什么？我尝试使其异步，现在发送50个请求所需的总时间是，正如他们在之前的评论中告诉您的那样，要实现您的目标，最好的方法是创建不同的线程，而不是使其异步

import requests
from tqdm import tqdm
import threading

url = "https://www.example.com/info/item"
headers = {
    'Content-Type': "application/x-www-form-urlencoded",
    'Access-Control-Allow-Origin': "*",
    'Accept-Encoding': "gzip, deflate",
    'Accept-Language': "en-US",
    }

n = 1
q = 50
sum = 0

def ThreadPOST(payload, headers):
    response = request.request("POST", url, data=payload, headers=headers)
    print(response.text)



for i in tqdm(range(n,q)):
    payload = "item_id={}".format(i+1)
    threading.Thread(target=ThreadPOST, args=(payload, headers)).start()
    sum = sum + i

---

这将产生50个线程，每个线程将上载其自身ID的数据。

我找到了上述异步代码的可用修复程序，并且效果非常好。：

import asyncio
import requests
import aiohttp
import time

async def make_numbers(numbers, _numbers):
    for i in range(numbers, _numbers):
        yield i

async def fetch():
    url = "https://www.example.com/info/item"
    async with aiohttp.ClientSession() as session:
        post_tasks = []
        # prepare the coroutines that poat
        async for x in make_numbers(1, 100):
            post_tasks.append(do_post(session, url, x))
        # now execute them all at once
        await asyncio.gather(*post_tasks)

async def do_post(session, url, x):
    headers = {
    'Content-Type': "application/x-www-form-urlencoded",
    'Access-Control-Allow-Origin': "*",
    'Accept-Encoding': "gzip, deflate",
    'Accept-Language': "en-US"
    }
    payload = "item_id={}".format(x)
    async with  session.post(url, data =payload,headers=headers) as response:
          data = await response.text()
          print("-> Created account number %d" % x)
          print (data)

s = time.perf_counter()
loop = asyncio.get_event_loop()
try:
    loop.run_until_complete(fetch())
finally:
    loop.close()

elapsed = time.perf_counter() - s
print(f"{__file__} executed in {elapsed:0.2f} seconds.")

---

你能为我解决上述问题吗异步不是我的专长。堆栈溢出不是代码编写服务。其目的是回答具体问题。对于并行POST请求，我以前使用过这个库：您要寻找的答案是

多线程

他们正在进行网络I/O，asyncio非常适合此类任务。

import asyncio
import requests
import aiohttp
import time

async def make_numbers(numbers, _numbers):
    for i in range(numbers, _numbers):
        yield i

async def fetch():
    url = "https://www.example.com/info/item"
    async with aiohttp.ClientSession() as session:
        post_tasks = []
        # prepare the coroutines that poat
        async for x in make_numbers(1, 100):
            post_tasks.append(do_post(session, url, x))
        # now execute them all at once
        await asyncio.gather(*post_tasks)

async def do_post(session, url, x):
    headers = {
    'Content-Type': "application/x-www-form-urlencoded",
    'Access-Control-Allow-Origin': "*",
    'Accept-Encoding': "gzip, deflate",
    'Accept-Language': "en-US"
    }
    payload = "item_id={}".format(x)
    async with  session.post(url, data =payload,headers=headers) as response:
          data = await response.text()
          print("-> Created account number %d" % x)
          print (data)

s = time.perf_counter()
loop = asyncio.get_event_loop()
try:
    loop.run_until_complete(fetch())
finally:
    loop.close()

elapsed = time.perf_counter() - s
print(f"{__file__} executed in {elapsed:0.2f} seconds.")