Scrapy 输出 [ 到我的 .json 文件中

Question

这里是一个真正的 Scrapy 和 Python 菜鸟，所以请耐心等待任何愚蠢的错误。我正在尝试编写一个蜘蛛来递归地抓取一个新闻站点并返回文章的标题、日期和第一段。我设法为一个项目爬取了一个页面，但是当我尝试扩展时，一切都出错了。

我的蜘蛛：

import scrapy
    from scrapy.contrib.spiders import CrawlSpider, Rule
    from scrapy.selector import Selector
    from scrapy.contrib.linkextractors.sgml import SgmlLinkExtractor
    from basic.items import BasicItem

    class BasicSpiderSpider(CrawlSpider):
        name = "basic_spider"
        allowed_domains = ["news24.com/"]
        start_urls = (
        'http://www.news24.com/SouthAfrica/News/56-children-hospitalised-for-food-poisoning-20150328',
        )

        rules = (Rule (SgmlLinkExtractor(allow=("", ))
        , callback="parse_items", follow= True),
        )
        def parse_items(self, response):
            hxs = Selector(response)
            titles = hxs.xpath('//*[@id="aspnetForm"]')
            items = []
            item = BasicItem()
            item['Headline'] = titles.xpath('//*[@id="article_special"]//h1/text()').extract()
            item["Article"] = titles.xpath('//*[@id="article-body"]/p[1]/text()').extract()
            item["Date"] = titles.xpath('//*[@id="spnDate"]/text()').extract()
            items.append(item)
            return items

我仍然遇到同样的问题，但我注意到每次尝试运行蜘蛛时都有一个“[”，为了尝试找出问题所在，我运行了以下命令：

c:\Scrapy Spiders\basic>scrapy parse --spider=basic_spider -c parse_items -d 2 -v http://www.news24.com/SouthAfrica/News/56-children-hospitalised-for-food-poisoning-20150328

这给了我以下输出：

2015-03-30 15:28:21+0200 [scrapy] INFO: Scrapy 0.24.5 started (bot: basic)
2015-03-30 15:28:21+0200 [scrapy] INFO: Optional features available: ssl, http11
2015-03-30 15:28:21+0200 [scrapy] INFO: Overridden settings: {'NEWSPIDER_MODULE': 'basic.spiders', 'SPIDER_MODULES': ['basic.spiders'], 'DEPTH_LIMIT': 1, 'DOW
NLOAD_DELAY': 2, 'BOT_NAME': 'basic'}
2015-03-30 15:28:21+0200 [scrapy] INFO: Enabled extensions: LogStats, TelnetConsole, CloseSpider, WebService, CoreStats, SpiderState
2015-03-30 15:28:21+0200 [scrapy] INFO: Enabled downloader middlewares: HttpAuthMiddleware, DownloadTimeoutMiddleware, UserAgentMiddleware, RetryMiddleware, D
efaultHeadersMiddleware, MetaRefreshMiddleware, HttpCompressionMiddleware, RedirectMiddleware, CookiesMiddleware, ChunkedTransferMiddleware, DownloaderStats
2015-03-30 15:28:21+0200 [scrapy] INFO: Enabled spider middlewares: HttpErrorMiddleware, OffsiteMiddleware, RefererMiddleware, UrlLengthMiddleware, DepthMiddl
eware
2015-03-30 15:28:21+0200 [scrapy] INFO: Enabled item pipelines:
2015-03-30 15:28:21+0200 [basic_spider] INFO: Spider opened
2015-03-30 15:28:21+0200 [basic_spider] INFO: Crawled 0 pages (at 0 pages/min), scraped 0 items (at 0 items/min)
2015-03-30 15:28:21+0200 [scrapy] DEBUG: Telnet console listening on 127.0.0.1:6023
2015-03-30 15:28:21+0200 [scrapy] DEBUG: Web service listening on 127.0.0.1:6080
2015-03-30 15:28:22+0200 [basic_spider] DEBUG: Crawled (200) <GET http://www.news24.com/SouthAfrica/News/56-children-hospitalised-for-food-poisoning-20150328>
 (referer: None)
2015-03-30 15:28:22+0200 [basic_spider] INFO: Closing spider (finished)
2015-03-30 15:28:22+0200 [basic_spider] INFO: Dumping Scrapy stats:
        {'downloader/request_bytes': 282,
         'downloader/request_count': 1,
         'downloader/request_method_count/GET': 1,
         'downloader/response_bytes': 145301,
         'downloader/response_count': 1,
         'downloader/response_status_count/200': 1,
         'finish_reason': 'finished',
         'finish_time': datetime.datetime(2015, 3, 30, 13, 28, 22, 177000),
         'log_count/DEBUG': 3,
         'log_count/INFO': 7,
         'response_received_count': 1,
         'scheduler/dequeued': 1,
         'scheduler/dequeued/memory': 1,
         'scheduler/enqueued': 1,
         'scheduler/enqueued/memory': 1,
         'start_time': datetime.datetime(2015, 3, 30, 13, 28, 21, 878000)}
2015-03-30 15:28:22+0200 [basic_spider] INFO: Spider closed (finished)

>>> DEPTH LEVEL: 1 <<<
# Scraped Items  ------------------------------------------------------------
[{'Article': [u'Johannesburg - Fifty-six children were taken to\nPietermaritzburg hospitals after showing signs of food poisoning while at\nschool, KwaZulu-Na
tal emergency services said on Friday.'],
  'Date': [u'2015-03-28 07:30'],
  'Headline': [u'56 children hospitalised for food poisoning']}]
# Requests  -----------------------------------------------------------------
[]

所以，我可以看到项目正在被抓取，但没有可用的项目数据放入 json 文件中。这就是我运行scrapy的方式：

scrapy crawl basic_spider -o test.json

我一直在查看最后一行（返回项目），因为将其更改为 yield 或 print 不会让我在解析中刮掉任何项目。

Answer 1

这通常意味着什么都没有被抓取，没有项目被提取。

在您的情况下，修复您的 allowed_domains 设置：

allowed_domains = ["news24.com"]

除此之外，稍微清理一下完美主义者：

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


class BasicSpiderSpider(CrawlSpider):
    name = "basic_spider"
    allowed_domains = ["news24.com"]
    start_urls = [
        'http://www.news24.com/SouthAfrica/News/56-children-hospitalised-for-food-poisoning-20150328',
    ]

    rules = [
        Rule(LinkExtractor(), callback="parse_items", follow=True),
    ]

    def parse_items(self, response):
        for title in response.xpath('//*[@id="aspnetForm"]'):
            item = BasicItem()
            item['Headline'] = title.xpath('//*[@id="article_special"]//h1/text()').extract()
            item["Article"] = title.xpath('//*[@id="article-body"]/p[1]/text()').extract()
            item["Date"] = title.xpath('//*[@id="spnDate"]/text()').extract()
            yield item