基于python爬虫和django打造的搜索引擎

# -*- coding: utf-8 -*- import scrapy from scrapy.http import Request from urllib import parse from ArticleSpider.items import JobBoleArticleItem, ArticleItemLoader from ArticleSpider.utils.common import get_md5 from scrapy.xlib.pydispatch import dispatcher from scrapy import signals import re import datetime class JobboleSpider(scrapy.Spider): name = "jobbole" allowed_domains = ["blog.jobbole.com"] start_urls = ['http://blog.jobbole.com/all-posts'] def parse(self, response): # 解析列表页中的所有文章url并交给scrapy下载后并进行解析 #post_nodes = response.css("#archive .floated-thumb .post-thumb a") post_nodes = response.xpath('//div[@class="post floated-thumb"]/div[@class="post-thumb"]//a') for post_node in post_nodes: # image_url = post_node.css("img::attr(src)").extract_first("") # post_url = post_node.css("::attr(href)").extract_first("") post_url = post_node.xpath('@href').extract_first("") image_url = post_node.xpath('img/@src').extract_first("") # post_url 是我们每一页的具体的文章url。 # 下面这个request是文章详情页面. 使用回调函数每下载完一篇就callback进行这一篇的具体解析。 # 我们现在获取到的是完整的地址可以直接进行调用。如果不是完整地址: 根据response.url + post_url # def urljoin(base, url)完成url的拼接 # 初始化好的Request如何交给scrapy进行下载: yield关键字 yield Request(url=parse.urljoin(response.url, post_url), meta={"front_image_url":image_url}, callback=self.parse_detail) #提取下一页并交给scrapy进行下载 next_url = response.css(".next.page-numbers::attr(href)").extract_first("") # 如果.next .pagenumber 是指两个class为层级关系。而不加空格为同一个标签 if next_url: yield Request(url=parse.urljoin(response.url, next_url), callback=self.parse) #yield和return的区别: yield生成值并不会中止程序的执行，返回值后程序继续往后执行，return返回值后，程序将中止执行 def parse_detail(self, response): article_item = JobBoleArticleItem() front_image_url = response.meta.get("front_image_url", "") title = response.xpath('//div[@class="entry-header"]/h1/text()').extract_first("") try: create_date = response.xpath("//p[@class='entry-meta-hide-on-mobile']/text()").extract()[0].strip().replace("·","").strip() except Exception as e: print(e) praise_nums = response.xpath("//span[contains(@class, 'vote-post-up')]/h10/text()").extract()[0] match_re = re.match(".*?(\d+).*", praise_nums) if match_re: praise_nums = match_re.group(1) else: praise_nums = 0 fav_nums = response.xpath("//span[contains(@class, 'bookmark-btn')]/text()").extract()[0] match_re = re.match(".*?(\d+).*", fav_nums) if match_re: fav_nums = match_re.group(1) else: fav_nums = 0 comment_nums = response.xpath("//a[@href='#article-comment']/span/text()").extract()[0] match_re = re.match(".*?(\d+).*", comment_nums) if match_re: comment_nums = match_re.group(1) else: comment_nums = 0 content = response.xpath("//div[@class='entry']").extract()[0] tag_list = response.xpath("//p[@class='entry-meta-hide-on-mobile']/a/text()").extract() tag_list = [element for element in tag_list if not element.strip().endswith("评论")] tags = ",".join(tag_list) print("-------------kaishi ------------") article_item["url_object_id"] = get_md5(response.url) article_item["title"] = title article_item["url"] = response.url try: create_date = datetime.datetime.strptime(create_date, "%Y/%m/%d").date() except Exception as e: create_date = datetime.datetime.now().date() article_item["create_date"] = create_date article_item["front_image_url"] = [front_image_url] article_item["praise_nums"] = praise_nums article_item["comment_nums"] = comment_nums article_item["fav_nums"] = fav_nums article_item["tags"] = tags article_item["content"] = content yield article_item