日志等级:
ERROR : 一般错误
WARNING : 警告
INFO : 一般的信息
DEBUG : 调试信息
默认的显示级别是DEBUG
可以在配置文件中settings中进行日志信息的指定输出:
#指定日志信息的输出
#LOG_LEVEL = 'DEBUG'
#将日志信息写入到文件中进行存储
LOG_FILE = 'log.txt'
二.请求传参
- 在某些情况下,我们爬取的数据不在同一个页面中,例如,我们爬取一个电影网站,电影的名称,评分在一级页面,而要爬取的其他电影详情在其二级子页面中。这时我们就需要用到请求传参。
- 案例展示:爬取www.id97.com电影网,将一级页面中的电影名称,类型,评分一级二级页面中的上映时间,导演,片长进行爬取。
# -*- coding: utf-8 -*- import scrapy from moviePro.items import MovieproItem class MovieSpider(scrapy.Spider): name = 'movie' allowed_domains = ['www.id97.com'] start_urls = ['http://www.id97.com/'] def parse(self, response): div_list = response.xpath('//div[@class="col-xs-1-5 movie-item"]') for div in div_list: item = MovieproItem() item['name'] = div.xpath('.//h1/a/text()').extract_first() item['score'] = div.xpath('.//h1/em/text()').extract_first() #xpath(string(.))表示提取当前节点下所有子节点中的数据值(.)表示当前节点 item['kind'] = div.xpath('.//div[@class="otherinfo"]').xpath('string(.)').extract_first() item['detail_url'] = div.xpath('./div/a/@href').extract_first() #请求二级详情页面,解析二级页面中的相应内容,通过meta参数进行Request的数据传递 yield scrapy.Request(url=item['detail_url'],callback=self.parse_detail,meta={'item':item}) def parse_detail(self,response): #通过response获取item item = response.meta['item'] item['actor'] = response.xpath('//div[@class="row"]//table/tr[1]/a/text()').extract_first() item['time'] = response.xpath('//div[@class="row"]//table/tr[7]/td[2]/text()').extract_first() item['long'] = response.xpath('//div[@class="row"]//table/tr[8]/td[2]/text()').extract_first() #提交item到管道 yield item
# -*- coding: utf-8 -*- # Define here the models for your scraped items # # See documentation in: # https://doc.scrapy.org/en/latest/topics/items.html import scrapy class MovieproItem(scrapy.Item): # define the fields for your item here like: name = scrapy.Field() score = scrapy.Field() time = scrapy.Field() long = scrapy.Field() actor = scrapy.Field() kind = scrapy.Field() detail_url = scrapy.Field()
# -*- coding: utf-8 -*- # Define your item pipelines here # # Don't forget to add your pipeline to the ITEM_PIPELINES setting # See: https://doc.scrapy.org/en/latest/topics/item-pipeline.html import json class MovieproPipeline(object): def __init__(self): self.fp = open('data.txt','w') def process_item(self, item, spider): dic = dict(item) print(dic) json.dump(dic,self.fp,ensure_ascii=False) return item def close_spider(self,spider): self.fp.close()