Question

我正在学习NLP，为此，我正在使用Scrapy抓取Amazon书评。我已经提取了想要的字段，并将其输出为Json文件格式。当将此文件作为df加载时，每个字段都记录为一个列表，而不是单独的每行格式。如何拆分此列表，以便df的每个项目都有一行，而不是所有项目条目都记录在单独的列表中？代码：

all

样本输出：

import scrapy


class ReviewspiderSpider(scrapy.Spider):
    name = 'reviewspider'
    allowed_domains = ['amazon.co.uk']
    start_urls = ['https://www.amazon.com/Gone-Girl-Gillian-Flynn/product-reviews/0307588378/ref=cm_cr_othr_d_paging_btm_1?ie=UTF8&reviewerType=all_reviews&pageNumber=1']

def parse(self, response):
    users = response.xpath('//a[contains(@data-hook, "review-author")]/text()').extract()
    titles = response.xpath('//a[contains(@data-hook, "review-title")]/text()').extract()
    dates = response.xpath('//span[contains(@data-hook, "review-date")]/text()').extract()
    found_helpful = response.xpath('//span[contains(@data-hook, "helpful-vote-statement")]/text()').extract()
    rating = response.xpath('//i[contains(@data-hook, "review-star-rating")]/span[contains(@class, "a-icon-alt")]/text()').extract()
    content = response.xpath('//span[contains(@data-hook, "review-body")]/text()').extract()

    yield {
        'users' : users.extract(),
        'titles' : titles.extract(),
        'dates' : dates.extract(),
        'found_helpful' : found_helpful.extract(),
        'rating' : rating.extract(),
        'content' : content.extract()
    }

所需的输出：

users = ['Lauren', 'James'...'John']
dates = ['on September 28, 2017', 'on December 26, 2017'...'on November 17, 2016']
rating = ['5.0 out of 5 stars', '2.0 out of 5 stars'...'5.0 out of 5 stars']

我知道应该编辑与蜘蛛相关的管道来实现此目的，但是我对Python的了解有限，无法理解Scrapy文档。我也尝试过here和here的解决方案，但是我还不知道能够用我自己的代码来合并答案。任何帮助将不胜感激。

Answer 1

重新阅读您的问题后，我很确定这是您想要的：

def parse(self, response):
    users = response.xpath('//a[contains(@data-hook, "review-author")]/text()').extract()
    titles = response.xpath('//a[contains(@data-hook, "review-title")]/text()').extract()
    dates = response.xpath('//span[contains(@data-hook, "review-date")]/text()').extract()
    found_helpful = response.xpath('//span[contains(@data-hook, "helpful-vote-statement")]/text()').extract()
    rating = response.xpath('//i[contains(@data-hook, "review-star-rating")]/span[contains(@class, "a-icon-alt")]/text()').extract()
    content = response.xpath('//span[contains(@data-hook, "review-body")]/text()').extract()

    for user, title, date, found_helpful, rating, content in zip(users, titles, dates, found_helpful, rating, content):
        yield {
            'user': user,
            'title': title,
            'date': date,
            'found_helpful': found_helpful,
            'rating': rating,
            'content': content
        }

或类似的东西。这就是我在第一个评论中试图暗示的内容。

Answer 2

编辑：我可以通过使用.css方法而不是.xpath提出解决方案。我用来从时尚零售商处抓取衬衫清单的蜘蛛：

import scrapy
from ..items import ProductItem

class SportsdirectSpider(scrapy.Spider):
    name = 'sportsdirect'
    allowed_domains = ['www.sportsdirect.com']
    start_urls = ['https://www.sportsdirect.com/mens/mens-shirts']

def parse(self, response):
    products = response.css('.s-productthumbbox')
    for p in products:
        brand = p.css('.productdescriptionbrand::text').extract_first()
        name = p.css('.productdescriptionname::text').extract_first()
        price = p.css('.curprice::text').extract_first()
        item = ProductItem()
        item['brand'] = brand
        item['name'] = name
        item['price'] = price
        yield item

Python-从Scrapy到Json输出拆分

2 个答案: