[开发工具]我的第一个scrapy爬取案例

爬取博客园首页信息

创建一个scrapy项目

scrapy startproject 项目名

?创建一个爬虫

scrapy genspider 爬虫名 域名

?

目录结构如下：

修改settings.py

把以下内容取消注释

DEFAULT_REQUEST_HEADERS = {
   'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8',
   'Accept-Language': 'en',
}
ITEM_PIPELINES = {
    'onesc.pipelines.OnescPipeline': 300,
}

我要抓取的是这些文字以及链接

接下来我要修改items.py和firstspider.py

items.py

# Define here the models for your scraped items
#
# See documentation in:
# https://docs.scrapy.org/en/latest/topics/items.html

import scrapy


class OnescItem(scrapy.Item):
    # define the fields for your item here like:
    # name = scrapy.Field()
    tit = scrapy.Field()#链接的文字
    tit1 = scrapy.Field()#链接的地址
    tex = scrapy.Field()#链接下面的文字

分析页面结构

修改firstspider.py

import scrapy
from scrapy import item
from onesc.items import OnescItem

class FirstspiderSpider(scrapy.Spider):
    name = 'firstspider'
    allowed_domains = ['www.cnblogs.com']
    start_urls = ['https://www.cnblogs.com/']

    def parse(self, response):
       item = OnescItem()
       item['tit'] = response.xpath('//a[@class="post-item-title"]/text()').extract()
       item['tit1'] = response.xpath('//a[@class="post-item-title"]/@href').extract()
       item['tex'] = response.xpath('//p[@class="post-item-summary"]/text()').extract()
       yield item

之后我们要对抓下来的数据进行保存

pipelines.py

# Define your item pipelines here
#
# Don't forget to add your pipeline to the ITEM_PIPELINES setting
# See: https://docs.scrapy.org/en/latest/topics/item-pipeline.html


# useful for handling different item types with a single interface
from itemadapter import ItemAdapter


class OnescPipeline:
    def process_item(self, item, spider):
        title = item['tit']
        titleurl = item['tit1']
        text = item['tex']
        with open('list.txt','w')as f:
            data=''
            for x,y,z in zip(title,titleurl,text):
                data+=x.strip()+'\t'+y.strip()+'\n'+z.strip()+'\n\n'
            f.write(data)
        return item

在scrapy.cfg的同级目录运行项目

scrapy crawl 爬虫的名字

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结果

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