Question

我刚刚完成了 Scrapy 教程，然后我开始将迄今为止学到的知识应用到一个新项目中。我正在尝试抓取一个论坛网站，但它基本上没有抓取任何内容......我已经检查了来自 scrapy shell 的 xpath 表达式，我总是得到想要的结果，但是当我从终端运行 crawl 命令时，它最终得到 0 个已抓取页面.经过数小时的紧张教程阅读和多次尝试后，我仍然没有任何进展。我错过了什么？感谢帮助

代码如下：

import scrapy
from scrapy.linkextractors import LinkExtractor
from scrapy.spiders import CrawlSpider, Rule


class ParserSpider(CrawlSpider):
    name = 'parser'
    allowed_domains = ['www.eksisozluk.com']
    start_urls = ['https://eksisozluk.com/basliklar/gundem']

    rules = (
        Rule((LinkExtractor(
            restrict_xpaths="//ul[@class='topic-list']/li/a")), callback='parse_item', follow=True, ),
    )

    def parse_item(self, response):
        yield {
            'title': response.xpath("//h1[@id='title']/a/text()").getall(),
            'entry': response.xpath("//div[@class='content']text()").getall(),
            'yazar': response.xpath("//a[@class='entry-author']/text()").getall(),
            'title': response.xpath("//a[@class='entry-date permalink']/text()").getall(),

        }

和输出：

...

2021-01-11 20:05:46 [scrapy.core.engine] INFO: Spider opened
2021-01-11 20:05:46 [scrapy.extensions.logstats] INFO: Crawled 0 pages (at 0 pages/min), scraped 0 items (at 0 items/min)
2021-01-11 20:05:46 [scrapy.extensions.telnet] INFO: Telnet console listening on 127.0.0.1:6024
2021-01-11 20:05:47 [scrapy.core.engine] DEBUG: Crawled (200) <GET https://eksisozluk.com/robots.txt> (referer: None)
2021-01-11 20:05:47 [scrapy.core.engine] DEBUG: Crawled (200) <GET https://eksisozluk.com/basliklar/gundem> (referer: None)
2021-01-11 20:05:48 [scrapy.spidermiddlewares.offsite] DEBUG: Filtered offsite request to 'eksisozluk.com': <GET https://eksisozluk.com/11-ocak-2021-kabine-toplantisi-kararlari--6794884?a=popular>
2021-01-11 20:05:48 [scrapy.core.engine] INFO: Closing spider (finished)
2021-01-11 20:05:48 [scrapy.statscollectors] INFO: Dumping Scrapy stats:
{'downloader/request_bytes': 499,
 'downloader/request_count': 2,
 'downloader/request_method_count/GET': 2,
 'downloader/response_bytes': 20870,
 'downloader/response_count': 2,
 'downloader/response_status_count/200': 2,
 'elapsed_time_seconds': 1.416214,
 'finish_reason': 'finished',
 'finish_time': datetime.datetime(2021, 1, 11, 17, 5, 48, 192682),
 'log_count/DEBUG': 3,
 'log_count/INFO': 10,
 'memusage/max': 54054912,
 'memusage/startup': 54054912,
 'offsite/domains': 1,
 'offsite/filtered': 50,
 'request_depth_max': 1,
 'response_received_count': 2,
 'robotstxt/request_count': 1,
 'robotstxt/response_count': 1,
 'robotstxt/response_status_count/200': 1,
 'scheduler/dequeued': 1,
 'scheduler/dequeued/memory': 1,
 'scheduler/enqueued': 1,
 'scheduler/enqueued/memory': 1,
 'start_time': datetime.datetime(2021, 1, 11, 17, 5, 46, 776468)}
2021-01-11 20:05:48 [scrapy.core.engine] INFO: Spider closed (finished)

Answer 1

一目了然，我建议您更改 4 件事，它们可能会增加您的 spider 运行正确返回抓取的数据的机会：

1) callback='parse_item', ---> callback=self.parse_item

2) allowed_domains = ['www.eksisozluk.com'] ---> allowed_domains = ['eksisozluk.com']

3) 'title': response.xpath("//a[@class='entry-date permalink']/text()").getall(), ---> 'title': response.xpath("//a[@class='entry-date permalink']/text()").getall()

4) follow=True, ) ---> follow=True)

更正以上所有内容，您的代码变为：

import scrapy
from scrapy.linkextractors import LinkExtractor
from scrapy.spiders import CrawlSpider, Rule


class ParserSpider(CrawlSpider):
    name = 'parser'
    allowed_domains = ['eksisozluk.com']
    start_urls = ['https://eksisozluk.com/basliklar/gundem']

    rules = (
        Rule((LinkExtractor(
            restrict_xpaths="//ul[@class='topic-list']/li/a")), callback=self.parse_item, follow=True),
    )

    def parse_item(self, response):
        yield {
            'title': response.xpath("//h1[@id='title']/a/text()").getall(),
            'entry': response.xpath("//div[@class='content']text()").getall(),
            'yazar': response.xpath("//a[@class='entry-author']/text()").getall(),
            'title': response.xpath("//a[@class='entry-date permalink']/text()").getall()

        }

另外，我建议您将主 callback 函数命名为 parse()，因为如果请求未指定回调，则将使用蜘蛛的 parse() 方法，即scrapy 正在寻找一个名为 parse() 的方法。

Answer 2

试试这个。我改变了allowed_domains https://docs.scrapy.org/en/latest/topics/spiders.html。未匹配您的目标网址和 allowed_domains 网址。

class ParserSpider(CrawlSpider):
    name = 'parser'
    allowed_domains = ['eksisozluk.com']
    start_urls = ['https://eksisozluk.com/basliklar/gundem']

    rules = (
        Rule((LinkExtractor(
            restrict_xpaths="//ul[@class='topic-list']/li/a")), callback='parse_item', follow=True, ),
    )

    def parse_item(self, response):
        yield {
            'title': response.xpath("//h1[@id='title']/a/text()").getall(),
            'entry': response.xpath("//div[@class='content']/text()").getall(),
            'yazar': response.xpath("//a[@class='entry-author']/text()").getall(),
            'title': response.xpath("//a[@class='entry-date permalink']/text()").getall(),

        }

scrapy 问题：抓取 0 页（以 0 页/分钟），抓取 0 个项目（以 0 个项目/分钟）

2 个答案: