1、使用Python3爬取美女图片-网站中的每日更新一栏

此代码是根据网络上其他人的代码优化而成的，

环境准备：

pip install lxml

pip install bs4

pip install urllib

 #!/usr/bin/env python
 #-*- coding: utf-8 -*-

 import requests
 from bs4 import BeautifulSoup
 import os
 import urllib
 import random

 class mzitu():

     def all_url(self, url):
         html = self.request(url)
         all_a = BeautifulSoup(html.text, 'lxml').find('div', class_='all').find_all('a')
         for a in all_a:
             title = a.get_text()
             print(u'开始保存：', title)
             title = title.replace(':', '')
             path = str(title).replace("?", '_')
             if not self.mkdir(path):  ##跳过已存在的文件夹
                 print(u'已经跳过：', title)
                 continue
             href = a['href']
             self.html(href)

     def html(self, href):
         html = self.request(href)
         max_span = BeautifulSoup(html.text, 'lxml').find('div', class_='pagenavi').find_all('span')[-2].get_text()
         for page in range(1, int(max_span) + 1):
             page_url = href + '/' + str(page)
             self.img(page_url)

     def img(self, page_url):
         img_html = self.request(page_url)
         img_url = BeautifulSoup(img_html.text, 'lxml').find('div', class_='main-image').find('img')['src']
         self.save(img_url, page_url)

     def save(self, img_url, page_url):
         name = img_url[-9:-4]
         try:
             img = self.requestpic(img_url, page_url)
             f = open(name + '.jpg', 'ab')
             f.write(img.content)
             f.close()
         except FileNotFoundError:  ##捕获异常，继续往下走
             print(u'图片不存在已跳过：', img_url)
             return False

     def mkdir(self, path):  ##这个函数创建文件夹
         path = path.strip()
         isExists = os.path.exists(os.path.join("D:\mzitu", path))
         if not isExists:
             print(u'建了一个名字叫做', path, u'的文件夹！')
             path = path.replace(':','')
             os.makedirs(os.path.join("D:\mzitu", path))
             os.chdir(os.path.join("D:\mzitu", path))  ##切换到目录
             return True
         else:
             print(u'名字叫做', path, u'的文件夹已经存在了！')
             return False

     def requestpic(self, url, Referer):  ##这个函数获取网页的response 然后返回
         user_agent_list = [ \
             "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.1 (KHTML, like Gecko) Chrome/22.0.1207.1 Safari/537.1" \
65-1　　　　　　　"Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:57.0) Gecko/20100101 Firefox/57.0",\
             "Mozilla/5.0 (X11; CrOS i686 2268.111.0) AppleWebKit/536.11 (KHTML, like Gecko) Chrome/20.0.1132.57 Safari/536.11", \
             "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/536.6 (KHTML, like Gecko) Chrome/20.0.1092.0 Safari/536.6", \
             "Mozilla/5.0 (Windows NT 6.2) AppleWebKit/536.6 (KHTML, like Gecko) Chrome/20.0.1090.0 Safari/536.6", \
             "Mozilla/5.0 (Windows NT 6.2; WOW64) AppleWebKit/537.1 (KHTML, like Gecko) Chrome/19.77.34.5 Safari/537.1", \
             "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/536.5 (KHTML, like Gecko) Chrome/19.0.1084.9 Safari/536.5", \
             "Mozilla/5.0 (Windows NT 6.0) AppleWebKit/536.5 (KHTML, like Gecko) Chrome/19.0.1084.36 Safari/536.5", \
             "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/536.3 (KHTML, like Gecko) Chrome/19.0.1063.0 Safari/536.3", \
             "Mozilla/5.0 (Windows NT 5.1) AppleWebKit/536.3 (KHTML, like Gecko) Chrome/19.0.1063.0 Safari/536.3", \
             "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_8_0) AppleWebKit/536.3 (KHTML, like Gecko) Chrome/19.0.1063.0 Safari/536.3", \
             "Mozilla/5.0 (Windows NT 6.2) AppleWebKit/536.3 (KHTML, like Gecko) Chrome/19.0.1062.0 Safari/536.3", \
             "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/536.3 (KHTML, like Gecko) Chrome/19.0.1062.0 Safari/536.3", \
             "Mozilla/5.0 (Windows NT 6.2) AppleWebKit/536.3 (KHTML, like Gecko) Chrome/19.0.1061.1 Safari/536.3", \
             "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/536.3 (KHTML, like Gecko) Chrome/19.0.1061.1 Safari/536.3", \
             "Mozilla/5.0 (Windows NT 6.1) AppleWebKit/536.3 (KHTML, like Gecko) Chrome/19.0.1061.1 Safari/536.3", \
             "Mozilla/5.0 (Windows NT 6.2) AppleWebKit/536.3 (KHTML, like Gecko) Chrome/19.0.1061.0 Safari/536.3", \
             "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/535.24 (KHTML, like Gecko) Chrome/19.0.1055.1 Safari/535.24", \
             "Mozilla/5.0 (Windows NT 6.2; WOW64) AppleWebKit/535.24 (KHTML, like Gecko) Chrome/19.0.1055.1 Safari/535.24"
         ]
         ua = random.choice(user_agent_list)
         headers = {'User-Agent': ua, "Referer": Referer}  ##较之前版本获取图片关键参数在这里
         content = requests.get(url, headers=headers)
         return content

     def request(self, url):  ##这个函数获取网页的response 然后返回
         headers = {
             'User-Agent': "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.1 (KHTML, like Gecko) Chrome/22.0.1207.1 Safari/537.1"}
         content = requests.get(url, headers=headers)
         return content

 Mzitu = mzitu()  ##实例化
 Mzitu.all_url('http://www.mzitu.com/all/')  ##给函数all_url传入参数  你可以当作启动爬虫（就是入口）
 print(u'恭喜您下载完成啦！')

执行步骤：

重复执行代码的话已保存的不会再次下载保存

执行结果：

遇到的错误如何解决：

1、错误提示：requests.exceptions.ChunkedEncodingError: ("Connection broken: ConnectionResetError(10054, '远程主机强迫关闭了一个现有的连接。', None, 10054, None)", ConnectionResetError(10054, '远程主机强迫关闭了一个现有的连接。', None, 10054, None))
错误原因分析：访问量瞬间过大，被网站反爬机制拦截了

解决方法:稍等一段时间再次执行即可

2、requests.exceptions.ChunkedEncodingError: ("Connection broken: ConnectionResetError(10054, '远程主机强迫关闭了一个现有的连接。', None, 10054, None)", ConnectionResetError(10054, '远程主机强迫关闭了一个现有的连接。', None, 10054, None))

错误原因分析：可能对方服务器做了反爬

解决方法：requests手动添加一下header