单线程和多线程下载文件

Posted 2020-12-07 laosun0204

单线程下载文件：

import requests
import time
from hashlib import md5


def down_load_pic(url):
    req = requests.get(url)
    m = md5(url.encode())
    with open(m.hexdigest() + ‘.png‘, ‘wb‘) as fw:  # md5后的名称作为图片的前缀
        fw.write(req.content)


url_list = [
             ‘http://www.nnzhp.cn/wp-content/uploads/2019/10/f410afea8b23fa401505a1449a41a133.png‘,
             ‘http://www.nnzhp.cn/wp-content/uploads/2019/11/481b5135e75c764b32b224c5650a8df5.png‘,
             ‘http://www.nnzhp.cn/wp-content/uploads/2019/11/b23755cdea210cfec903333c5cce6895.png‘,
             ‘http://www.nnzhp.cn/wp-content/uploads/2019/11/542824dde1dbd29ec61ad5ea867ef245.png‘,
           ]

start_time = time.time()
for url in url_list:
    down_load_pic(url)
end_time = time.time()
print(end_time - start_time)

多线程下载文件：

import requests
import time
import threading
from hashlib import md5


def down_load_pic(url):
    req = requests.get(url)
    m = md5(url.encode())
    with open(m.hexdigest() + ‘.png‘, ‘wb‘) as fw:
        fw.write(req.content)


url_list = [
             ‘http://www.nnzhp.cn/wp-content/uploads/2019/10/f410afea8b23fa401505a1449a41a133.png‘,
             ‘http://www.nnzhp.cn/wp-content/uploads/2019/11/481b5135e75c764b32b224c5650a8df5.png‘,
             ‘http://www.nnzhp.cn/wp-content/uploads/2019/11/b23755cdea210cfec903333c5cce6895.png‘,
             ‘http://www.nnzhp.cn/wp-content/uploads/2019/11/542824dde1dbd29ec61ad5ea867ef245.png‘,
           ]


start_time = time.time()
for url in url_list:
    t = threading.Thread(target=down_load_pic, args=(url,))
    t.start()
while threading.activeCount() != 1:
    pass
end_time = time.time()
print(end_time - start_time)