学习笔记（爬虫）：爬取任意百度吧帖子中的图片和视频 2

续上篇：https://www.cnblogs.com/maxxu11/p/12626007.html

1、代码：

# -*- coding: utf-8 -*-
import requests
from lxml import etree
import os
from urllib import parse
#爬虫
class BtcSpider(object):
    def __init__(self):
        #爬取美女吧图片
        #解析：美女吧url地址，pn值决定页数，pn =0 ，表示第一页，pn = 50 表示第二页……
        self.url = 'https://tieba.baidu.com/f?kw={}&ie=utf-8&pn={}'
        self.headers = {
            'User-Agent': 'Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.11 (KHTML, like Gecko) Chrome/23.0.1271.64 Safari/537.11',
        }


    #发送请求
    def get_response(self,url):
        response = requests.get(url,headers = self.headers)
        data = response.text
        return data
    #发送请求获取网页数据，数据读取方式为二进制content形式
    def get_data(self,url):
        data  = requests.get(url,headers = self.headers).content
        return data
    #解析数据,封装xpath
    def get_xpath(self,html,pattern):
        #构建树
        p = etree.HTML(html)
        #解析网页内容，获取url_lists
        result = p.xpath(pattern)
        return result
    #下载图片&
    def download_src(self,url):
        html = self.get_response(url)
        html = html.replace("<!--", "")
        pattern1 = '//div[@class="threadlist_title pull_left j_th_tit "]/a/@href'
        #获取每个帖子的url地址
        url_lists = self.get_xpath(html,pattern1)
        base_url = "http://tieba.baidu.com/"
        true_lists = []
        for i in url_lists:
            #帖子完整的url地址
            tie_url = "http://tieba.baidu.com" + i
            tie_html = self.get_response(tie_url)
            pattern2 = '//img[@class="BDE_Image"]/@src | //div[@class="video_src_wrapper"]/embed/@data-video'
            img_lists = self.get_xpath(tie_html,pattern2)
            #下载图片
            self.save_data(img_lists)

    #保存数据
    def save_data(self,url_lists):
        for url in url_lists:
            img_data = self.get_data(url)
            file_name = url[-10:]
            print('正在下载图片：',file_name)
            file_path = self.dir+'\'+file_name
            with open(file_path,'wb')as f:
                f.write(img_data)
    def run(self):
        word = input("请输入关键词：")
        begin = int(input("请输入起始页："))
        end = int(input("请输入终止页："))
        #转化格式
        name = parse.quote(word)
        os.makedirs(word, exist_ok=True)
        self.dir = word
        #设置需要爬取的页数
        for i in range(begin,end):
            i = (i-1)*50
            url = self.url.format(name,i)
            self.download_src(url)
if __name__ == "__main__":
    spider = BtcSpider()
    spider.run()