python - 无法在 scrapy.Response 上调用 css() 或 xpath()

Question

我试着用scrapy 写了一个网络爬虫。然而，当我尝试使用它的交互式 shell 来测试 one of the page .

错误信息，

2016-03-01 22:15:08 [scrapy] INFO: Scrapy 1.0.5 started (bot: momo)
2016-03-01 22:15:08 [scrapy] INFO: Optional features available: ssl, http11
2016-03-01 22:15:08 [scrapy] INFO: Overridden settings: {'NEWSPIDER_MODULE': 'momo.spiders', 'FEED_FORMAT': 'json', 'SPIDER_MODULES': ['momo.spiders'], 'FEED_URI': 'j.json', 'BOT_NAME': 'momo'}
2016-03-01 22:15:08 [scrapy] INFO: Enabled extensions: CloseSpider, FeedExporter, TelnetConsole, LogStats, CoreStats, SpiderState
2016-03-01 22:15:08 [scrapy] INFO: Enabled downloader middlewares: HttpAuthMiddleware, DownloadTimeoutMiddleware, UserAgentMiddleware, RetryMiddleware, DefaultHeadersMiddleware, MetaRefreshMiddleware, HttpCompressionMiddleware, RedirectMiddleware, CookiesMiddleware, ChunkedTransferMiddleware, DownloaderStats
2016-03-01 22:15:08 [scrapy] INFO: Enabled spider middlewares: HttpErrorMiddleware, OffsiteMiddleware, RefererMiddleware, UrlLengthMiddleware, DepthMiddleware
2016-03-01 22:15:08 [scrapy] INFO: Enabled item pipelines: 
2016-03-01 22:15:08 [scrapy] INFO: Spider opened
2016-03-01 22:15:08 [scrapy] INFO: Crawled 0 pages (at 0 pages/min), scraped 0 items (at 0 items/min)
2016-03-01 22:15:08 [scrapy] DEBUG: Telnet console listening on 127.0.0.1:6023
2016-03-01 22:15:09 [scrapy] DEBUG: Crawled (200) <GET http://www.momoshop.com.tw/main/Main.jsp> (referer: None)
2016-03-01 22:15:11 [scrapy] DEBUG: Crawled (200) <GET http://www.momoshop.com.tw/goods/GoodsDetail.jsp?i_code=1697199&str_category_code=2200700058&cid=ec&oid=1c&mdiv=1000000000-bt_0_209_01-bt_0_209_01_e11&ctype=B> (referer: http://www.momoshop.com.tw/main/Main.jsp)
2016-03-01 22:15:11 [scrapy] DEBUG: Crawled (200) <GET http://www.momoshop.com.tw/goods/GoodsDetail.jsp?i_code=3753480&str_category_code=1514200303&cid=ec&oid=2a&mdiv=1000000000-bt_0_209_01-bt_0_209_01_e25&ctype=B> (referer: http://www.momoshop.com.tw/main/Main.jsp)
2016-03-01 22:15:11 [scrapy] DEBUG: Crawled (200) <GET http://www.momoshop.com.tw/goods/GoodsDetail.jsp?i_code=3754704&str_category_code=1417802005&cid=ec&oid=1f&mdiv=1000000000-bt_0_209_01-bt_0_209_01_e20&ctype=B> (referer: http://www.momoshop.com.tw/main/Main.jsp)
2016-03-01 22:15:11 [scrapy] DEBUG: Crawled (200) <GET http://www.momoshop.com.tw/goods/GoodsDetail.jsp?i_code=3811447&str_category_code=1318900078&cid=ec&oid=1d&mdiv=1000000000-bt_0_209_01-bt_0_209_01_e14&ctype=B> (referer: http://www.momoshop.com.tw/main/Main.jsp)
{'Date': ['Tue, 01 Mar 2016 14:15:10 GMT'], 'Set-Cookie': ['loginRsult=null;Expires=Thu, 01-Jan-01970 00:00:10 GMT;Path=/', 'loginUser=null;Expires=Thu, 01-Jan-01970 00:00:10 GMT;Path=/', 'cardUser=null;Expires=Thu, 01-Jan-01970 00:00:10 GMT;Path=/', '18YEARAGREE=null;Expires=Thu, 01-Jan-01970 00:00:10 GMT;Path=/', 'Browsehist=1697199,3753480,3754704,2189725;Path=/', 'FTOOTH=22;Path=/', 'DCODE=2200700058;Path=/'], 'Content-Type': ['']}
2016-03-01 22:15:11 [scrapy] ERROR: Spider error processing <GET http://www.momoshop.com.tw/goods/GoodsDetail.jsp?i_code=1697199&str_category_code=2200700058&cid=ec&oid=1c&mdiv=1000000000-bt_0_209_01-bt_0_209_01_e11&ctype=B> (referer: http://www.momoshop.com.tw/main/Main.jsp)
Traceback (most recent call last):
  File "/Users/Shane/Desktop/scrapy/lib/python2.7/site-packages/scrapy/utils/defer.py", line 102, in iter_errback
    yield next(it)
  File "/Users/Shane/Desktop/scrapy/lib/python2.7/site-packages/scrapy/spidermiddlewares/offsite.py", line 28, in process_spider_output
    for x in result:
  File "/Users/Shane/Desktop/scrapy/lib/python2.7/site-packages/scrapy/spidermiddlewares/referer.py", line 22, in <genexpr>
    return (_set_referer(r) for r in result or ())
  File "/Users/Shane/Desktop/scrapy/lib/python2.7/site-packages/scrapy/spidermiddlewares/urllength.py", line 37, in <genexpr>
    return (r for r in result or () if _filter(r))
  File "/Users/Shane/Desktop/scrapy/lib/python2.7/site-packages/scrapy/spidermiddlewares/depth.py", line 54, in <genexpr>
    return (r for r in result or () if _filter(r))
  File "/Users/Shane/Desktop/scrapy/momo/momo/spiders/default_spider.py", line 35, in parseGoods
    item.item = response.css('h1').extract()
AttributeError: 'Response' object has no attribute 'css'

---

更新

我发现这个特定页面的响应中没有Content-Type，它写在head/meta上。

代码

import scrapy

from scrapy.http import Request

class MomoItem(scrapy.Item):
    item  = scrapy.Field()
    price = scrapy.Field()
    specification = scrapy.Field()

class MomoSpider(scrapy.Spider):
    name = "momo"
    allowed_domains = ["www.momoshop.com.tw"]
    start_urls = [
        "http://www.momoshop.com.tw/main/Main.jsp"
    ]

    def parse(self, response):
        for href in response.xpath('//a[contains(@href, "/goods")]/@href'):
            url = response.urljoin(href.extract())
            yield Request(url, callback=self.parseGoods)

        # for href in response.xpath('//a[contains(@href, "/category")]'):
        #     url = response.urljoin(href.extract())
        #     yield scrapy.Request(url, callback=self.parse)
        #
        # for href in response.xpath('//a[contains(@href, "/brand")]'):
        #     url = response.urljoin(href.extract())
        #     yield scrapy.Request(url, callback=self.parse)


    def parseGoods(self, response):
        item = MomoItem()
        print(response.headers)
        item.item = response.css('h1').extract()
        item.price = response.xpath('//ul[@class="prdPrice"]/li/span/text()').extract()
        print(item)

        yield item

---

回应JeD的回答

Traceback (most recent call last):
  File "/Users/Shane/Desktop/scrapy/lib/python2.7/site-packages/scrapy/utils/defer.py", line 45, in mustbe_deferred
    result = f(*args, **kw)
  File "/Users/Shane/Desktop/scrapy/lib/python2.7/site-packages/scrapy/core/spidermw.py", line 48, in process_spider_input
    return scrape_func(response, request, spider)
  File "/Users/Shane/Desktop/scrapy/lib/python2.7/site-packages/scrapy/core/scraper.py", line 145, in call_spider
    dfd.addCallbacks(request.callback or spider.parse, request.errback)
  File "/Users/Shane/Desktop/scrapy/lib/python2.7/site-packages/twisted/internet/defer.py", line 299, in addCallbacks
    assert callable(callback)
AssertionError

Answer 1

问题出在默认的 scrapy HTML Parser 上。一旦我切换到另一个解析器，它就像一个魅力。 lxml 似乎没有像 Beautiful Soup 4 那样完美地解析损坏的 HTML。

from bs4 import BeautifulSoup

import scrapy

class MomoItem(scrapy.Item):
    item  = scrapy.Field()
    price = scrapy.Field()
    # specification = scrapy.Field()

class MomoSpider(scrapy.Spider):
    name = "momo"
    allowed_domains = ["www.momoshop.com.tw"]
    start_urls = ["http://www.momoshop.com.tw/main/Main.jsp"]

    def parse(self, response):
        for href in response.xpath('//a[contains(@href, "/goods")]/@href'):
            url = response.urljoin(href.extract())
            self.parseGoods(response)
            yield scrapy.Request(url, callback=self.parseGoods)

        # for href in response.xpath('//a[contains(@href, "/category")]'):
        #     url = response.urljoin(href.extract())
        #     yield scrapy.Request(url, callback=self.parse)
        #
        # for href in response.xpath('//a[contains(@href, "/brand")]'):
        #     url = response.urljoin(href.extract())
        #     yield scrapy.Request(url, callback=self.parse)


    def parseGoods(self, response):
        soup = BeautifulSoup(response._body, 'html.parser')

        item = MomoItem()
        item['item'] = soup.find_all('h1')[0].get_text()
        item['price'] = soup.find_all('ul', class_='prdPrice')[0]
                            .find_all('li', class_='special')[0].span.get_text()
        yield item