我使用以下代码使用scrapey来抓取数据:
from scrapy.selector import Selector
from scrapy.spider import Spider
class ExampleSpider(Spider):
name = "example"
allowed_domains = ["dmoz.org"]
start_urls = [
"http://www.dmoz.org/Computers/Programming/Languages/Python/Books/",
"http://www.dmoz.org/Computers/Programming/Languages/Python/Resources/"
]
def parse(self, response):
sel = Selector(response)
for li in sel.xpath('//ul/li'):
title = li.xpath('a/text()').extract()
link = li.xpath('a/@href').extract()
desc = li.xpath('text()').extract()
print title, link, desc
然而,当我运行这个蜘蛛时,我收到以下消息:
2014-06-30 23:39:00-0500 [scrapy] INFO: Scrapy 0.24.1 started (bot: tutorial)
2014-06-30 23:39:00-0500 [scrapy] INFO: Optional features available: ssl, http11
2014-06-30 23:39:00-0500 [scrapy] INFO: Overridden settings: {'NEWSPIDER_MODULE': 'tutorial.spiders', 'FEED_FORMAT': 'csv', 'SPIDER_MODULES': ['tutorial.spiders'], 'FEED_URI': 'willthiswork.csv', 'BOT_NAME': 'tutorial'}
2014-06-30 23:39:01-0500 [scrapy] INFO: Enabled extensions: FeedExporter, LogStats, TelnetConsole, CloseSpider, WebService, CoreStats, SpiderState
2014-06-30 23:39:01-0500 [scrapy] INFO: Enabled downloader middlewares: HttpAuthMiddleware, DownloadTimeoutMiddleware, UserAgentMiddleware, RetryMiddleware, DefaultHeadersMiddleware, MetaRefreshMiddleware, HttpCompressionMiddleware, RedirectMiddleware, CookiesMiddleware, ChunkedTransferMiddleware, DownloaderStats
2014-06-30 23:39:01-0500 [scrapy] INFO: Enabled spider middlewares: HttpErrorMiddleware, OffsiteMiddleware, RefererMiddleware, UrlLengthMiddleware, DepthMiddleware
2014-06-30 23:39:01-0500 [scrapy] INFO: Enabled item pipelines:
2014-06-30 23:39:01-0500 [example] INFO: Spider opened
2014-06-30 23:39:01-0500 [example] INFO: Crawled 0 pages (at 0 pages/min), scraped 0 items (at 0 items/min)
2014-06-30 23:39:01-0500 [scrapy] DEBUG: Telnet console listening on 127.0.0.1:6023
2014-06-30 23:39:01-0500 [scrapy] DEBUG: Web service listening on 127.0.0.1:6080
2014-06-30 23:39:01-0500 [example] DEBUG: Crawled (200) <GET http://www.dmoz.org/Computers/Programming/Languages/Python/Resources/> (referer: None)
值得注意的是“Crawled 0 pages(0页/分.....以及被覆盖的设置)。
此外,我打算写入数据的文件完全空白。
我做错了导致数据无法写入吗?
答案 0 :(得分:1)
我假设您正在尝试使用scrapy crawl tutorial -o myfile.json
要使这项工作,您需要使用scrapy项目。
将以下内容添加到 items.py :
def MozItem(Item):
title = Field()
link = Field()
desc = Field()
并调整解析功能
def parse(self, response):
sel = Selector(response)
item = MozItem()
for li in sel.xpath('//ul/li'):
item['title'] = li.xpath('a/text()').extract()
item['link'] = li.xpath('a/@href').extract()
item['desc'] = li.xpath('text()').extract()
yield item