python 爬取豆瓣电影案例

# conding=utf-8
from  parse import parse_url
import json
class DoubanSpider:

    def __init__(self):

        self.temp_url = "https://m.douban.com/rexxar/api/v2/subject_collection/filter_movie_occident_hot/items?os=android&for_mobile=1&callback=jsonp3&start={}&count=18&loc_id=108288&_=0"


    def get_content_list(self,html_str): #提取数据

        dict_data = json.loads(html_str)

        content_list = dict_data["subject_collection_items"]

        total =dict_data["total"]

        return content_list,total


    def save_content_list(self,content_list):

        with open("db.json","a",encoding="utf-8") as f:

            for content in content_list:

                f.write(json.dumps(content,ensure_ascii=False))

                f.write("\n")
                print('添加成功')

    def run(self): #实现主要逻辑

        num = 0

        total = 100

        while num < total + 18:
            # 1.start_url
            start_url = self.temp_url.format(num)

            # 2.发送请求,获取响应
            html_str = parse_url(start_url)

            # 3.提取数据
            content_list, total = self.get_content_list(html_str)

            # 4.保存
            self.save_content_list(content_list)

            # 5.构造下一页的url地址,循环2-5步
            num +=18



if __name__== '__main__':
        douban = DoubanSpider()
        douban.run()