python - 抓取项目列表并将其合并到一个属性中

Question

我当前的蜘蛛仅解析产品属性，而不解析item['title']。我如何将它们结合在一起页面示例:

https://universalmotors.ru/motorcycles/lifan/motorcycle-lifan-lf150-13-2017/

我的蜘蛛:

# -*- coding: utf-8 -*-
from scrapy.spiders import SitemapSpider as CrawlSpider
from ..items import DistPracticalItem


class SitemapSpider(CrawlSpider):
    name = 'sitemap3'
    allowed_domains = ['universalmotors.ru']
    sitemap_urls = ['https://universalmotors.ru/sitemap.xml']
    # sitemap_follow = ['deal']
    # sitemap_rules = [(r'^https?://sz.*deal/[0-8]{1,8}\.html$', 'parse_item')]
    sitemap_rules = [('/motorcycles/', 'parse_item')]

    def parse_item(self, response):
        item = DistPracticalItem()
      #  item['name'] = response.xpath('//h1[contains(@class,"good__title")]/text()').extract_first()
        item['title'] = response.css("h1.good__title::text").extract()
     #   prop = response.xpath('normalize-space(//tr[@itemprop="additionalProperty"])').extract()
        item['price'] = response.css('div.deal-info span.campaign-price').css('::text').extract_first()
     #   item['comments'] = response.css('div.comment div.total').css('::text').extract()
#        return item
     #   for item in response.xpath('//tr[@itemprop="additionalProperty"]'):
        for item in response.xpath('//tr[@itemprop="additionalProperty"]'):
           yield {
                'name': item.xpath('normalize-space(./*[@class="label_table"])').extract_first(),
                'value': item.xpath('normalize-space(./*[@class="value_table"])').extract_first(),
#                'title': response.css("h1.good__title::text").extract()
            }

我的目标是获取包含以下属性列表的已抓取项目列表:

Title of the Item 1| Price 1 | Property 1, Property 2, property 3
Title of the Item 2| Price 2 | Property 1, Property 2, property 3
Title of the Item 3| Price 3 | Property 1, Property 2, property 3

Answer 1

您必须生成要抓取的完整项目，您的代码仅生成属性，而不生成标题和价格。

我修改了你的代码，它似乎按预期工作。我删除了该项目包含和一些注释以使其在我的机器上运行。

from scrapy.spiders import SitemapSpider as CrawlSpider


class SitemapSpider(CrawlSpider):
    name = 'sitemap3'
    allowed_domains = ['universalmotors.ru']
    sitemap_urls = ['https://universalmotors.ru/sitemap.xml']
    sitemap_rules = [('/motorcycles/', 'parse_item')]

    def parse_item(self, response):
        item = dict()
        item['title'] = response.css("h1.good__title::text").extract_first()
        item['price'] = response.css('div.deal-info span.campaign-price').css('::text').extract_first()
        item['properties'] = list()
        for prop in response.xpath('//tr[@itemprop="additionalProperty"]'):
            item['properties'].append(
                {
                    'name': prop.xpath('normalize-space(./*[@class="label_table"])').extract_first(),
                    'value': prop.xpath('normalize-space(./*[@class="value_table"])').extract_first(),
                }
            )
        yield item

请注意，我正在收集 item 变量内的所有信息，在本例中是一个 dict，在您的变量中是一个 DistPracticalItem .

您最终将得到以下架构:

{
  'title': string,
  'price': string,
  'properties': list of dicts with 'name' and 'value' as strings
}

希望我说得清楚。