Scrapy蜘蛛不会爬行

Question

我正在尝试测试scrapy CrawlSpider，但我不明白它为什么不爬行。它应该做的是只为一个深度级别爬取维基百科的数学页面，并返回每个爬取页面的标题。我想念什么？非常感谢您的帮助！

from scrapy.spiders import CrawlSpider, Rule
from scrapy.linkextractors import LinkExtractor
from scrapy.selector import Selector
from Beurs.items import WikiItem

class WikiSpider(CrawlSpider):
    name = 'WikiSpider'
    allowed_domains = ['wikipedia.org']
    start_urls = ["http://en.wikipedia.org/wiki/Mathematics"]

    Rules = (
        Rule(LinkExtractor(restrict_xpaths=('//div[@class="mw-body"]//a/@href'))),
        Rule(LinkExtractor( allow=("http://en.wikipedia.org/wiki/",)),     callback='parse_item', follow=True),        
        )


def parse_item(self, response):
    sel = Selector(response)  
    rows = sel.xpath('//span[@class="innhold"]/table/tr')
    items = []

        for row in rows[1:]:
            item = WikiItem()
            item['agent'] = row.xpath('./td[1]/a/text()|./td[1]/text()').extract()
            item['org'] = row.xpath('./td[2]/text()').extract()
            item['link'] = row.xpath('./td[1]/a/@href').extract()
            item['produkt'] = row.xpath('./td[3]/text()').extract()
        items.append(item)
        return items

设置：

BOT_NAME = 'Beurs'

SPIDER_MODULES = ['Beurs.spiders']
NEWSPIDER_MODULE = 'Beurs.spiders'
DOWNLOAD_HANDLERS = {
  's3': None,
}
DEPTH_LIMIT = 1

还有日志：

C:\Users\Jan Willem\Anaconda\Beurs>scrapy crawl BeursSpider
2015-11-07 15:14:36 [scrapy] INFO: Scrapy 1.0.3 started (bot: Beurs)
2015-11-07 15:14:36 [scrapy] INFO: Optional features available: ssl, http11,    boto
2015-11-07 15:14:36 [scrapy] INFO: Overridden settings: {'NEWSPIDER_MODULE': 'Beurs.spiders', 'SPIDER_MODULES': ['Beurs.spiders'], 'DEPTH_LIMIT': 1,    'BOT_NAME': 'Beurs'}
2015-11-07 15:14:36 [scrapy] INFO: Enabled extensions: CloseSpider, TelnetConsole, LogStats, CoreStats, SpiderState
2015-11-07 15:14:36 [scrapy] INFO: Enabled downloader middlewares: HttpAuthMiddleware, DownloadTimeoutMiddleware, UserAgentMiddleware, RetryMiddleware, DefaultHeadersMiddleware, MetaRefreshMiddleware, HttpCompressionMiddleware, RedirectMiddleware, CookiesMiddleware, ChunkedTransferMiddleware, DownloaderStats
2015-11-07 15:14:36 [scrapy] INFO: Enabled spider middlewares: HttpErrorMiddleware, OffsiteMiddleware, RefererMiddleware, UrlLengthMiddleware, DepthMiddleware
2015-11-07 15:14:36 [scrapy] INFO: Enabled item pipelines:
2015-11-07 15:14:36 [scrapy] INFO: Spider opened
2015-11-07 15:14:36 [scrapy] INFO: Crawled 0 pages (at 0 pages/min), scraped 0 items (at 0 items/min)
2015-11-07 15:14:36 [scrapy] DEBUG: Telnet console listening on 127.0.0.1:6023
2015-11-07 15:14:36 [scrapy] DEBUG: Redirecting (301) to <GET https://en.wikipedia.org/wiki/Mathematics> from <GET http://en.wikipedia.org/wiki/Mathematics>
2015-11-07 15:14:37 [scrapy] DEBUG: Crawled (200) <GET https://en.wikipedia.org/wiki/Mathematics> (referer: None)
2015-11-07 15:14:37 [scrapy] INFO: Closing spider (finished)
2015-11-07 15:14:37 [scrapy] INFO: Dumping Scrapy stats:
{'downloader/request_bytes': 530,
 'downloader/request_count': 2,
 'downloader/request_method_count/GET': 2,
 'downloader/response_bytes': 60393,
 'downloader/response_count': 2,
 'downloader/response_status_count/200': 1,
 'downloader/response_status_count/301': 1,
 'finish_reason': 'finished',
 'finish_time': datetime.datetime(2015, 11, 7, 14, 14, 37, 274000),
 'log_count/DEBUG': 3,
 'log_count/INFO': 7,
 'response_received_count': 1,
 'scheduler/dequeued': 2,
 'scheduler/dequeued/memory': 2,
 'scheduler/enqueued': 2,
 'scheduler/enqueued/memory': 2,
 'start_time': datetime.datetime(2015, 11, 7, 14, 14, 36, 852000)}
2015-11-07 15:14:37 [scrapy] INFO: Spider closed (finished)

Answer 1

所以基本上你的正则表达式不太正确，你的 Xpath 需要一些调整。我认为下面的代码符合您的要求，所以请尝试一下，如果您需要更多帮助，请告诉我：

def parse_item(self, response):
    sel = Selector(response)
    rows = sel.xpath('//span[@class="innhold"]/table/tr')
    items = []

    for row in rows[1:]:
        item = SasItem()
        item['agent'] = row.xpath('./td[1]/a/text()|./td[1]/text()').extract()
        item['org'] = row.xpath('./td[2]/text()').extract()
        item['link'] = row.xpath('./td[1]/a/@href').extract()
        item['produkt'] = row.xpath('./td[3]/text()').extract()
        items.append(item)
    return items