Question

我正在制作一个项目，其中我使用scrapy从网站中删除项目，但问题是，该网站的前2页的xpath与其他页面的xpath不同。结果我的蜘蛛只是抓住前两页的项目而只是简单地爬过其他页面。我怎么能让我的蜘蛛也刮掉页面上的东西？

我也在这里包括我的蜘蛛，以便你可以在必要时看透我的蜘蛛。

from scrapy.spider import BaseSpider
from scrapy.selector import HtmlXPathSelector
from project2.items import Project2Item
from scrapy.http import Request

class ProjectSpider(BaseSpider):
    name = "project2spider"
    allowed_domains = ["http://directory.thesun.co.uk/"]
    current_page_no = 1
    start_urls = [
        'http://directory.thesun.co.uk/find/uk/computer-repair'
        ]

    def get_next_url(self, fired_url):
        if '/page/' in fired_url:
            url, page_no = fired_url.rsplit('/page/', 1)
        else:
            if self.current_page_no != 1:
                #end of scroll
                return 
        self.current_page_no += 1
        return "http://directory.thesun.co.uk/find/uk/computer-repair/page/%s" % self.current_page_no

# the parse procedure, and here is the codes which declares which field to scrap. 
    def parse(self, response):
        fired_url = response.url
        hxs = HtmlXPathSelector(response)
        sites = hxs.select('//div[@class="abTbl "]')

        for site in sites:
            item = Project2Item()
            item['Catogory'] = site.select('span[@class="icListBusType"]/text()').extract()
            item['Bussiness_name'] = site.select('a/@title').extract()
            item['Description'] = site.select('span[last()]/text()').extract()
            item['Number'] = site.select('span[@class="searchInfoLabel"]/span/@id').extract()
            item['Web_url'] = site.select('span[@class="searchInfoLabel"]/a/@href').extract()
            item['adress_name'] = site.select('span[@class="searchInfoLabel"]/span/text()').extract()
            item['Photo_name'] = site.select('img/@alt').extract()
            item['Photo_path'] = site.select('img/@src').extract()
            #items.append(item)
            yield item
        next_url = self.get_next_url(fired_url)
        if next_url:
            yield Request(next_url, self.parse, dont_filter=True)

我需要使用其他页面：sites = hxs.select('//div[@class="icListItem"]')

如何将它包含在我的蜘蛛中，以便它也可以从其他页面中删除项目..

目前正在抓取前两页，只是抓住其他页面。

Answer 1

到目前为止你做了什么？一种解决方案是在调用下一页时使用作为元数据传递的类索引参数。类似的东西：

def parse(self, response):
    hxs = HtmlXPathSelector(response)
    2nd_xpath = False
    try:
        if response.meta['index'] > 1:
            2nd_xpath = True
        index = response.meta['index']
    except KeyError:
        index = 0
    sites = (hxs.select('//div[@class="icListItem"]') if 2nd_xpath
             else hxs.select('//div[@class="abTbl "]'))

    ...

    request = Request(next_url, self.parse, dont_filter=True)
    request.meta['index'] = index + 1
    yield request

该代码确实可以改进，但你明白了。

Scrapy蜘蛛只是爬行而不刮

1 个答案: