为scrapy中的每个类别制作单独的输出文件

Question

我尝试根据黄页的类别抓取黄页。所以我从一个文本文件加载类别并将其提供给 start_urls。我在这里面临的问题是为每个类别分别保存输出。以下是我尝试实现的代码：

CATEGORIES = []
with open('Catergories.txt', 'r') as f:
    data = f.readlines()

    for category in data:
        CATEGORIES.append(category.strip())

在 settings.py 中打开文件并在蜘蛛中创建一个访问列表。

蜘蛛：

# -*- coding: utf-8 -*-
from scrapy.linkextractors import LinkExtractor
from scrapy.spiders import CrawlSpider, Rule

from ..items import YellowItem
from scrapy.utils.project import get_project_settings

settings = get_project_settings()


class YpSpider(CrawlSpider):
    categories = settings.get('CATEGORIES')

    name = 'yp'
    allowed_domains = ['yellowpages.com']

    start_urls = ['https://www.yellowpages.com/search?search_terms={0}&geo_location_terms=New%20York'
                      '%2C '
                      '%20NY'.format(*categories)]
    rules = (

        Rule(LinkExtractor(restrict_xpaths='//a[@class="business-name"]', allow=''), callback='parse_item',
             follow=True),

        Rule(LinkExtractor(restrict_xpaths='//a[@class="next ajax-page"]', allow=''),
             follow=True),
    )

    def parse_item(self, response):
        categories = settings.get('CATEGORIES')
        print(categories)
        item = YellowItem()
        # for data in response.xpath('//section[@class="info"]'):
        item['title'] = response.xpath('//h1/text()').extract_first()
        item['phone'] = response.xpath('//p[@class="phone"]/text()').extract_first()
        item['street_address'] = response.xpath('//h2[@class="address"]/text()').extract_first()
        email = response.xpath('//a[@class="email-business"]/@href').extract_first()
        try:
            item['email'] = email.replace("mailto:", '')
        except AttributeError:
            pass
        item['website'] = response.xpath('//a[@class="primary-btn website-link"]/@href').extract_first()
        item['Description'] = response.xpath('//dd[@class="general-info"]/text()').extract_first()
        item['Hours'] = response.xpath('//div[@class="open-details"]/descendant-or-self::*/text()[not(ancestor::*['
                                       '@class="hour-category"])]').extract()
        item['Other_info'] = response.xpath(
            '//dd[@class="other-information"]/descendant-or-self::*/text()').extract()
        category_ha = response.xpath('//dd[@class="categories"]/descendant-or-self::*/text()').extract()
        item['Categories'] = " ".join(category_ha)
        item['Years_in_business'] = response.xpath('//div[@class="number"]/text()').extract_first()
        neighborhood = response.xpath('//dd[@class="neighborhoods"]/descendant-or-self::*/text()').extract()
        item['neighborhoods'] = ' '.join(neighborhood)
        item['other_links'] = response.xpath('//dd[@class="weblinks"]/descendant-or-self::*/text()').extract()

        item['category'] = '{0}'.format(*categories)

        return item

       

这里是 pipelines.py 文件：

from scrapy import signals
from scrapy.exporters import CsvItemExporter
from scrapy.utils.project import get_project_settings

settings = get_project_settings()


class YellowPipeline(object):
    @classmethod
    def from_crawler(cls, crawler):
        pipeline = cls()
        crawler.signals.connect(pipeline.spider_opened, signals.spider_opened)
        crawler.signals.connect(pipeline.spider_closed, signals.spider_closed)
        return pipeline

    def spider_opened(self, spider):
        self.exporters = {}
        categories = settings.get('CATEGORIES')

        file = open('{0}.csv'.format(*categories), 'w+b')

        exporter = CsvItemExporter(file, encoding='cp1252')
        exporter.fields_to_export = ['title', 'phone', 'street_address', 'website', 'email', 'Description',
                                     'Hours', 'Other_info', 'Categories', 'Years_in_business', 'neighborhoods',
                                     'other_links']
        exporter.start_exporting()
        for category in categories:
            self.exporters[category] = exporter

    def spider_closed(self, spider):

        for exporter in iter(self.exporters.items()):
            exporter.finish_exporting()

    def process_item(self, item, spider):

        self.exporters[item['category']].export_item(item)
        return item

运行代码后出现以下错误：

exporter.finish_exporting()
AttributeError: 'tuple' object has no attribute 'finish_exporting'

每个类别我都需要单独的 csv 文件。任何帮助将不胜感激。

Answer 1

我会在后期处理中这样做。将所有项目导出到一个带有类别字段的 .csv 文件。我认为你没有以正确的方式思考这个问题，并且过于复杂化了。不确定这是否可行，但值得一试:)

with open('parent.csv', 'r') as file:
    reader = csv.reader(file)
    for row in reader:
        with open('{}.csv'.format(row[category]), 'a') as f:
            writer = csv.writer(f)
            writer.writerow(row)

您也可以使用蜘蛛关闭信号应用此代码。

https://docs.scrapy.org/en/latest/topics/signals.html#scrapy.signals.spider_closed

Answer 2

dict.items() 返回可迭代的，其中每个项目看起来像 tuple (key, value) 要消除此错误，您需要删除 iter 并解压缩像 for category, exporter in self.exporter.items(): 这样的项目