软件工程实践专题第一次作业

对伯乐在线所有文章进行爬取

使用scrapy框架

jobbolen.py

# -*- coding: utf-8 -*-
import scrapy
from scrapy.http import request
from urllib import parse
from scrapytext.items import article_item
class jobbolenspider(scrapy.spider):
    name = 'jobbolen'
    allowed_domains = ['blog.jobbole.com']
    start_urls = ['http://blog.jobbole.com/all-posts/']

    def parse(self, response):
        re_nodes= response.css('#archive .floated-thumb .post-thumb a')
        for re_node in re_nodes:
            image_url=re_node.css("img::attr(src)").extract_first()
            re_url=re_node.css('::attr(href)').extract_first()
            yield request(url=parse.urljoin(response.url,re_url),meta={'front_url_image':image_url},callback=self.text_parse)#yield交给scrapy进行自动下载
        next_urls=response.css('.next.page-numbers::attr(href)').extract_first()
        if next_urls:
            yield request(url=parse.urljoin(response.url, re_url), callback=self.parse)

    def text_parse(self,response):
        article_item=article_item()
        re_title = response.css('.entry-header h1::text').extract()[0]
        re_text = response.css('.entry p::text').extract()
        front_image=response.meta.get("front_url_image","")
        article_item["title"]=re_title
        article_item["text"]=re_text
        article_item["front_image"]=front_image
        yield article_item

items.py配置

# -*- 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 scrapytextitem(scrapy.item):
    # define the fields for your item here like:
    # name = scrapy.field()
    pass
class article_item(scrapy.item):
    title=scrapy.field()
    text=scrapy.field()
    front_image=scrapy.field()
    front_image_path=scrapy.field()

setting.py配置
import os

robotstxt_obey = false

images_urls_field ="front_image"#从item中找出那个是要保存的
project_dir=os.path.abspath(os.path.dirname(__file__))
images_store=os.path.join(project_dir,'images')#将图片保存在本地文件中



main.py

# -*- coding: utf-8 -*-
__auther__="booby"
from scrapy.cmdline import execute
import sys
import os
sys.path.append(os.path.dirname(os.path.abspath(__file__)))
execute(["scrapy","crawl","jobbolen"])


运行出现错误：

解决方案：

由于将一个字符串传递给数组导致错误

将jobbolen.py中的front_image改成[front_image]

运行结果

 

 

提取出文章及标题和封面图片