使用scrapy刮網站

Question

我正在嘗試用scrapy刮一個網站 ，但是我在從這個網站上抓取所有產品時遇到問題，因為它正在使用無休止的滾動...

我只能抓下52件商品的數據，但他們是3824件商品。

hxs.select("//span[@class='itm-Catbrand strong']").extract()
hxs.select("//span[@class='itm-price ']").extract()
hxs.select("//span[@class='itm-title']").extract()

如果我使用hxs.select("//div[@id='content']/div/div/div").extract()然后它提取整個項目列表但不會進一步過濾....如何做我刮掉所有物品？

我試過這個但結果相同。 我哪里錯了？

def parse(self, response):
    filename = response.url.split("/")[-2]
    open(filename, 'wb').write(response.body
    for n in [2,3,4,5,6]:            
    req = Request(url="http://www.jabong.com/men/shoes/?page=" + n,
                      headers = {"Referer": "http://www.jabong.com/men/shoes/",
                                 "X-Requested-With": response.header['X-Requested-With']})
    return req 

Answer 1

正如您所猜測的，當您滾動頁面時，此網站使用javascript加載更多項目。

使用瀏覽器中包含的開發人員工具（Ctrl-Maj i for chromium），我在網絡選項卡中看到頁面中包含的javascript腳本執行以下請求以加載更多項目：

GET http://www.website-your-are-crawling.com/men/shoes/?page=2 # 2,3,4,5,6 etc...

Web服務器使用以下類型的文檔進行響應：

<li id="PH969SH70HPTINDFAS" class="itm hasOverlay unit size1of4 ">
  <div id="qa-quick-view-btn" class="quickviewZoom itm-quickview ui-buttonQuickview l-absolute pos-t" title="Quick View" data-url ="phosphorus-Black-Moccasins-233629.html" data-sku="PH969SH70HPTINDFAS" onClick="_gaq.push(['_trackEvent', 'BadgeQV','Shown','OFFER INSIDE']);">Quick view</div>

                                    <div class="itm-qlInsert tooltip-qlist  highlightStar"
                     onclick="javascript:Rocket.QuickList.insert('PH969SH70HPTINDFAS', 'catalog');
                                             return false;" >
                                              <div class="starHrMsg">
                         <span class="starHrMsgArrow">&nbsp;</span>
                         Save for later                         </div>
                                        </div>
                <a id='cat_105_PH969SH70HPTINDFAS' class="itm-link sobrTxt" href="/phosphorus-Black-Moccasins-233629.html" 
                                    onclick="fireGaq('_trackEvent', 'Catalog to PDP', 'men--Shoes--Moccasins', 'PH969SH70HPTINDFAS--1699.00--', this),fireGaq('_trackEvent', 'BadgePDP','Shown','OFFER INSIDE', this);">
                    <span class="lazyImage">
                        <span style="width:176px;height:255px;" class="itm-imageWrapper itm-imageWrapper-PH969SH70HPTINDFAS" id="http://static4.jassets.com/p/Phosphorus-Black-Moccasins-6668-926332-1-catalog.jpg" itm-img-width="176" itm-img-height="255" itm-img-sprites="4">
                            <noscript><img src="http://static4.jassets.com/p/Phosphorus-Black-Moccasins-6668-926332-1-catalog.jpg" width="176" height="255" class="itm-img"></noscript>
                        </span>                            
                    </span>

                                            <span class="itm-budgeFlag offInside"><span class="flagBrdLeft"></span>OFFER INSIDE</span>                       
                                            <span class="itm-Catbrand strong">Phosphorus</span>
                    <span class="itm-title">
                                                                                Black Moccasins                        </span>

這些文件包含更多項目。

因此，要獲得完整的項目列表，您必須在Spider的parse方法中返回Request對象（請參閱Spider類文檔 ），告訴scrapy它應該加載更多數據：

def parse(self, response):
    # ... Extract items in the page using extractors
    n = number of the next "page" to parse
    # You get get n by using response.url, extracting the number
    # at the end and adding 1

    # It is VERY IMPORTANT to set the Referer and X-Requested-With headers
    # here because that's how the website detects if the request was made by javascript
    # or direcly by following a link.
    req = Request(url="http://www.website-your-are-crawling.com/men/shoes/?page=" + n,
       headers = {"Referer": "http://www.website-your-are-crawling.com/men/shoes/",
          "X-Requested-With": "XMLHttpRequest"})
    return req # and your items

哦，順便說一句（如果你想測試），你不能只在瀏覽器中加載http://www.website-your-are-crawling.com/men/shoes/?page=2看看返回的內容是因為如果X-Requested-With標頭與XMLHttpRequest不同，網站會將您重定向到全局頁面（即http://www.website-your-are-crawling.com/men/shoes/ ）。