百度贴吧图片爬虫

import requests
from lxml import etree
import os

class Baidu(object):

    def __init__(self, name):
        self.url = 'http://tieba.baidu.com/f?ie=utf-8&kw={}'.format(name)
        # 使用较老版本的请求头，该浏览器不支持js
        self.headers = {
            'User-Agent': 'Mozilla/4.0 (compatible; MSIE 5.01; Windows NT 5.0) '
        }

    # 发送请求，获取响应
    def get_data(self, url):
        response = requests.get(url,headers=self.headers)
        return response.content

    # 解析列表页数据，获取列表页面帖子的标题和链接
    def parse_list_page(self, data):
        with open('baidu.html','wb') as f:
            f.write(data)
        # 实例化etree对象
        html = etree.HTML(data)
        # 使用xpath语法，提取网页数据
        node_list = html.xpath("//*[@id='thread_list']/li[@class=' j_thread_list clearfix']/div/div[2]/div[1]/div[1]/a")
        # 判断获取结果
        # print(len(node_list))
        data_list = []
        # 遍历node_list
        for node in node_list:
            temp = {}
            temp['url'] = 'http://tieba.baidu.com' + node.xpath('./@href')[0]
            temp['title'] = node.xpath('./text()')[0]
            data_list.append(temp)

        # 提取下一页的节点
        next_node = html.xpath('//*[@id="frs_list_pager"]/a[last()-1]/@href')[0]
        # print(next_node)
        # 拼接下一页的完整url
        next_url = 'http:' + next_node
        # print(next_url)
        return data_list,next_url

    def parse_detail_page(self, data_list):
        html = etree.HTML(data_list)
        # 提取详情页面的图片链接
        image_list = html.xpath("//cc/div[contains(@class,'d_post')]/img[@class='BDE_Image']/@src")
        # 返回图片节点列表
        print(image_list)
        return image_list

    # 下载图片，保存图片文件
    # 创建文件夹
    def download(self, image_list):
        if not os.path.exists('images'):
            os.makedirs('images')
        for image in image_list:
            # os.sep在mac系统中是/,如果是windows系统，\\,跨平台
            file_name = 'images'+ os.sep + image.split('/')[-1]
            image_data = self.get_data(image)
            with open(file_name,'wb') as f:
                f.write(image_data)

    def run(self):
        # 构造url和请求头
        # 发送请求，获取响应
        next_url = self.url
        # 开启循环，
        while next_url:
            data = self.get_data(next_url)

            # 解析列表页数据，返回的列表数据、下一页的的数据
            data_list,next_url = self.parse_list_page(data)
            # 解析详情页的数据，获取详情页的图片的链接地址
            for data in data_list:
                url = data['url']
                result_list = self.get_data(url)
                image_list = self.parse_detail_page(result_list)
                # 保存数据，下载图片
                self.download(image_list)

if __name__ == '__main__':
    # 爬取百度校花吧所有图片并存在文件夹中
    baidu = Baidu('校花吧')
    baidu.run()