没有错误，只是DEBUG: crawl(200)和referer: None)

Question

我试图从一个韩国网页上抓取一些数据，但失败了。虽然xpath查询在浏览器过滤器中运行良好，但根本没有抓取任何数据。下面是我的Python代码片段。谢谢你的帮助。附注:这些片段是根据@Alexander的建议编辑的。

import scrapy 
class CoursesSpider(scrapy.Spider):
name = 'courses'
allowed_domains = ['www.codealive.co.kr']
start_urls = ['https://www.codealive.co.kr']
def parse(self, response):
for course in response.xpath("//section[@id='course']//ul/li"):
yield{
'title': course.xpath("./h2/text()").get(),
'hours': course.xpath("./div/strong/text()").get(),
'content': course.xpath("./div/p/text()").get()
}

调试日志为:

2022-12-09 20:15:18 [scrapy.utils.log] INFO: Scrapy 1.6.0 started
(bot: codealive) 2022-12-09 20:15:18 [scrapy.utils.log] INFO:
Versions: lxml 4.8.0.0, libxml2 2.9.12, cssselect 1.2.0, parsel
1.7.0, w3lib 1.22.0, Twisted 21.7.0, Python 3.7.15 (default, Nov 24 2022, 12:02:37) - [Clang 14.0.6 ], pyOpenSSL 22.0.0 (OpenSSL 1.1.1s 
1 Nov 2022), cryptography 38.0.2, Platform
Darwin-22.1.0-x86_64-i386-64bit 2022-12-09 20:15:18 [scrapy.crawler]
INFO: Overridden settings: {'BOT_NAME': 'codealive',
'NEWSPIDER_MODULE': 'codealive.spiders', 'SPIDER_MODULES':
['codealive.spiders'], 'USER_AGENT': 'Mozilla/5.0 (Windows NT 10.0;
Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.372'}
2022-12-09 20:15:18 [scrapy.extensions.telnet] INFO: Telnet Password:
35b6e238174899c0 2022-12-09 20:15:18 [scrapy.middleware] INFO:
Enabled extensions: ['scrapy.extensions.corestats.CoreStats', 
'scrapy.extensions.telnet.TelnetConsole', 
'scrapy.extensions.memusage.MemoryUsage', 
'scrapy.extensions.logstats.LogStats'] 2022-12-09 20:15:18
[scrapy.middleware] INFO: Enabled downloader middlewares:
['scrapy.downloadermiddlewares.httpauth.HttpAuthMiddleware', 
'scrapy.downloadermiddlewares.downloadtimeout.DownloadTimeoutMiddleware',
'scrapy.downloadermiddlewares.defaultheaders.DefaultHeadersMiddleware',
'scrapy.downloadermiddlewares.useragent.UserAgentMiddleware', 
'scrapy.downloadermiddlewares.retry.RetryMiddleware', 
'scrapy.downloadermiddlewares.redirect.MetaRefreshMiddleware', 
'scrapy.downloadermiddlewares.httpcompression.HttpCompressionMiddleware',
'scrapy.downloadermiddlewares.redirect.RedirectMiddleware', 
'scrapy.downloadermiddlewares.cookies.CookiesMiddleware', 
'scrapy.downloadermiddlewares.httpproxy.HttpProxyMiddleware', 
'scrapy.downloadermiddlewares.stats.DownloaderStats'] 2022-12-09
20:15:18 [scrapy.middleware] INFO: Enabled spider middlewares:
['scrapy.spidermiddlewares.httperror.HttpErrorMiddleware', 
'scrapy.spidermiddlewares.offsite.OffsiteMiddleware', 
'scrapy.spidermiddlewares.referer.RefererMiddleware', 
'scrapy.spidermiddlewares.urllength.UrlLengthMiddleware', 
'scrapy.spidermiddlewares.depth.DepthMiddleware'] 2022-12-09 20:15:18
[scrapy.middleware] INFO: Enabled item pipelines: [] 2022-12-09
20:15:18 [scrapy.core.engine] INFO: Spider opened 2022-12-09 20:15:18
[scrapy.extensions.logstats] INFO: Crawled 0 pages (at 0 pages/min),
scraped 0 items (at 0 items/min) 2022-12-09 20:15:18
[scrapy.extensions.telnet] INFO: Telnet console listening on
127.0.0.1:6023 2022-12-09 20:15:18 [scrapy.core.engine] DEBUG: Crawled (200) <GET https://www.codealive.co.kr> (referer: None)
2022-12-09 20:15:18 [scrapy.core.engine] INFO: Closing spider
(finished) 2022-12-09 20:15:18 [scrapy.statscollectors] INFO: Dumping
Scrapy stats: {'downloader/request_bytes': 280, 
'downloader/request_count': 1, 
'downloader/request_method_count/GET': 1, 
'downloader/response_bytes': 9694,  'downloader/response_count': 1, 
'downloader/response_status_count/200': 1,  'finish_reason':
'finished',  'finish_time': datetime.datetime(2022, 12, 9, 11, 15,
18, 903893),  'log_count/DEBUG': 1,  'log_count/INFO': 9, 
'memusage/max': 58916864,  'memusage/startup': 58916864, 
'response_received_count': 1,  'scheduler/dequeued': 1, 
'scheduler/dequeued/memory': 1,  'scheduler/enqueued': 1, 
'scheduler/enqueued/memory': 1,  'start_time':
datetime.datetime(2022, 12, 9, 11, 15, 18, 730596)} 2022-12-09
20:15:18 [scrapy.core.engine] INFO: Spider closed (finished)

Answer 1

你差一点…我认为主要问题是，你有一个解析函数内部的解析函数，虽然我不确定这不仅仅是复制和粘贴你的代码打字错误。

其他几点，只要有一个@id标记，你应该总是利用它，因为它们通常是唯一的。

使xpath选择器尽可能简单，也有利于提高可读性。

例如:

import scrapy
class CoursesSpider(scrapy.Spider):
name = 'courses'
allowed_domains = ['www.codealive.co.kr']
start_urls = ['https://www.codealive.co.kr']
def parse(self, response):
for course in response.xpath("//section[@id='course']//ul/li"):
yield{
'title': course.xpath("./h2/text()").get(),
'hours': course.xpath("./div/strong/text()").get(),
'content':course.xpath("./div/p/text()").get()
}

输出:

2022-12-09 05:08:40 [scrapy.extensions.logstats] INFO: Crawled 0 pages (at 0 pages/min), scraped 0 items (at 0 items/min)
2022-12-09 05:08:40 [scrapy.extensions.telnet] INFO: Telnet console listening on 127.0.0.1:6024
2022-12-09 05:08:40 [scrapy.core.engine] DEBUG: Crawled (200) <GET https://www.codealive.co.kr> (referer: None)
2022-12-09 05:08:41 [scrapy.core.scraper] DEBUG: Scraped from <200 https://www.codealive.co.kr>
{'title': 'Power Base', 'hours': '24 Lessons x 100min', 'content': 'Python의 기본문법'}
2022-12-09 05:08:41 [scrapy.core.scraper] DEBUG: Scraped from <200 https://www.codealive.co.kr>
{'title': 'Core Algorithm', 'hours': '24 Lessons x 100min', 'content': '스택(stack), 큐(queue)등'}
2022-12-09 05:08:41 [scrapy.core.scraper] DEBUG: Scraped from <200 https://www.codealive.co.kr>
{'title': 'Super AI', 'hours': '24 Lessons x 100min', 'content': '머신러닝 에이전트를 이용한'}
2022-12-09 05:08:41 [scrapy.core.engine] INFO: Closing spider (finished)
2022-12-09 05:08:41 [scrapy.statscollectors] INFO: Dumping Scrapy stats:
{'downloader/request_bytes': 296,
'downloader/request_count': 1,
'downloader/request_method_count/GET': 1,
'downloader/response_bytes': 9694,
'downloader/response_count': 1,
'downloader/response_status_count/200': 1,
'elapsed_time_seconds': 0.808256,
'finish_reason': 'finished',
'finish_time': datetime.datetime(2022, 12, 9, 13, 8, 41, 105546),
'httpcompression/response_bytes': 32492,
'httpcompression/response_count': 1,
'item_scraped_count': 3,
'log_count/DEBUG': 5,
'log_count/INFO': 10,
'response_received_count': 1,
'scheduler/dequeued': 1,
'scheduler/dequeued/memory': 1,
'scheduler/enqueued': 1,
'scheduler/enqueued/memory': 1,
'start_time': datetime.datetime(2022, 12, 9, 13, 8, 40, 297290)}
2022-12-09 05:08:41 [scrapy.core.engine] INFO: Spider closed (finished)