使用mongodb保存爬取豆瓣电影的数据

1. 创建爬虫项目douban

   scrapy startproject douban
   
   

2. 设置items.py文件，存储要保存的数据类型和字段名称

   # -*- coding: utf-8 -*-
   
   import scrapy
   
   
   class DoubanItem(scrapy.Item):
   
       title = scrapy.Field()
       # 内容
       content = scrapy.Field()
       # 评分
       rating_num = scrapy.Field()
       # 简介
       quote = scrapy.Field()
   
   

3. 设置爬虫文件doubanmovies.py

   # -*- coding: utf-8 -*-
   import scrapy
   from douban.items import DoubanItem
   
   
   class DoubanmoviesSpider(scrapy.Spider):
       name = 'doubanmovies'
       allowed_domains = ['movie.douban.com']
       offset = 0
       url = 'https://movie.douban.com/top250?start='
       start_urls = [url + str(offset)]
   
       def parse(self, response):
           # print('*'*60)
           # print(response.url)
           # print('*'*60)
   
           item = DoubanItem()
           info = response.xpath("//div[@class='info']")
           for each in info:
               item['title'] = each.xpath(".//span[@class='title'][1]/text()").extract()
               item['content'] = each.xpath(".//div[@class='bd']/p[1]/text()").extract()
               item['rating_num'] = each.xpath(".//span[@class='rating_num']/text()").extract()
               item['quote'] = each .xpath(".//span[@class='inq']/text()").extract()
               yield item
               # print(item)
   
           self.offset += 25
           if self.offset <= 250:
               yield scrapy.Request(self.url + str(self.offset),callback=self.parse)
   
   

4. 设置管道文件，使用mongodb数据库来保存爬取的数据。重点部分

   # -*- coding: utf-8 -*-
   
   from scrapy.conf import settings
   import pymongo
   
   class DoubanPipeline(object):
       def __init__(self):
           self.host = settings['MONGODB_HOST']
           self.port = settings['MONGODB_PORT']
   
   
   
       def process_item(self, item, spider):
           # 创建mongodb客户端连接对象，该例从settings.py文件里面获取mongodb所在的主机和端口参数，可直接书写主机和端口
           self.client = pymongo.MongoClient(self.host,self.port)
   
           # 创建数据库douban
           self.mydb = self.client['douban']
   
           # 在数据库douban里面创建表doubanmovies
   
           # 把类似字典的数据转换为phthon字典格式
           content = dict(item)
   
           # 把数据添加到表里面
           self.mysheetname.insert(content)
   
           return item
   
   

5. 设置settings.py文件

   # -*- coding: utf-8 -*-
   
   BOT_NAME = 'douban'
   
   SPIDER_MODULES = ['douban.spiders']
   NEWSPIDER_MODULE = 'douban.spiders'
   
   USER_AGENT = 'Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0;'
   
   
   # Configure a delay for requests for the same website (default: 0)
   
   
   # See https://doc.scrapy.org/en/latest/topics/settings.html#download-delay
   
   
   # See also autothrottle settings and docs
   
   DOWNLOAD_DELAY = 3
   
   # The download delay setting will honor only one of:
   
   
   #CONCURRENT_REQUESTS_PER_DOMAIN = 16
   
   
   #CONCURRENT_REQUESTS_PER_IP = 16
   
   
   
   # Disable cookies (enabled by default)
   
   COOKIES_ENABLED = False
   
   
   # Configure item pipelines
   
   
   # See https://doc.scrapy.org/en/latest/topics/item-pipeline.html
   
   ITEM_PIPELINES = {
      'douban.pipelines.DoubanPipeline': 300,
   }
   
   
   
   # mongodb数据库设置变量
   
   MONGODB_HOST = '127.0.0.1'
   MONGODB_PORT = 27017
   
   

6. 终端测试

   scrapy crawl douban
   
   

这博客园的代码片段缩进，难道要用4个空格才可以搞定？我发现只能使用4个空格才能解决如上图的代码块的缩进