练习：豆瓣电影TOP250爬虫（优化）

import requests
from lxml import html
import pandas as pd
def spider():
    movie_list = []
    for i in range(0, 226, 25):
        url = 'https://movie.douban.com/top250?start={}&filter='.format(i)
        headers = {'User-Agent': 'Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.131 Safari/537.36'}

        # 请求url
        response = requests.get(url, headers=headers)
        selector = html.fromstring(response.text)
        # 用xpath语法抓取数据放入容器中
        li_list = selector.xpath('//div[@id="content"]/div[@class="grid-16-8 clearfix"]/div[@class="article"]/ol[@class="grid_view"]/li')

        for li in li_list:
            movie_img = li.xpath('div[@class="item"]/div[@class="pic"]/a/img/@src')
            movie_img = '找不到数据' if len(movie_img)==0 else movie_img[0]
            # print(movie_img)
            movie_id = li.xpath('div[@class="item"]/div[@class="pic"]/em/text()')
            movie_id = '找不到数据' if len(movie_id) == 0 else int(movie_id[0])
            # print(movie_id)
            movie_name = li.xpath('div[@class="item"]/div[@class="info"]/div[@class="hd"]/a/span[1]/text()')
            movie_name = '找不到数据' if len(movie_name) == 0 else movie_name[0]
            # print(movie_name)
            movie_link = li.xpath('div[@class="item"]/div[@class="info"]/div[@class="hd"]/a/@href')
            movie_link = '找不到数据' if len(movie_link) == 0 else movie_link[0]
            # print(movie_link)
            movie_info = li.xpath('div[@class="item"]/div[@class="info"]/div[@class="bd"]/p[1]/text()')
            movie_info = '找不到数据' if len(movie_info) == 0 else movie_info[0].strip()
            # print(movie_info)
            movie_rating_num = li.xpath('div[@class="item"]/div[@class="info"]/div[@class="bd"]/div[@class="star"]/span[@class="rating_num"]/text()')
            movie_rating_num = '找不到数据' if len(movie_rating_num) == 0 else float(movie_rating_num[0])
            # print(movie_rating_num)
            movie_rating_people = li.xpath('div[@class="item"]/div[@class="info"]/div[@class="bd"]/div[@class="star"]/span[4]/text()')
            movie_rating_people = '找不到数据' if len(movie_rating_people) == 0 else int(movie_rating_people[0].replace('人评价', ''))
            # print(movie_rating_people)
            movie_quote = li.xpath('div[@class="item"]/div[@class="info"]/div[@class="bd"]/p[@class="quote"]/span/text()')
            movie_quote = '找不到数据' if len(movie_quote) == 0 else movie_quote[0]
            # print(movie_quote)
            movie_list.append({
                'movie_img': movie_img,
                'movie_id': movie_id,
                'movie_name': movie_name,
                'movie_link': movie_link,
                'movie_info': movie_info,
                'movie_rating_num': movie_rating_num,
                'movie_rating_people': movie_rating_people,
                'movie_quote': movie_quote
            })

        # print(movie_list)
        # 存入本地
    pd.DataFrame(movie_list).to_csv('豆瓣top250.csv')
    for movie in movie_list:
        print(movie)
        with open('./douban_top250_img/{}.jpg'.format(movie['movie_name']), 'wb') as f:
            f.write(requests.get(movie['movie_img'], headers=headers).content)
    print('共爬取了{}部电影'.format(len(movie_list)))
spider()

豆瓣电影TOP250
豆瓣电影TOP250