Scrapy：crawlspider没有生成给定URL中的所有链接

Question

我无法废弃以下网址中的数据。我试图废弃它，但在我的机器中它显示了一些不相关的数据。

网址1：http://www.amazon.com/s/ref=nb_sb_noss_1?url=search-alias%3Daps&field-keywords=samsung%20appliances&sprefix=samsung+applia%2Caps&rh=i%3Aaps%2Ck%3Asamsung%20appliances

网址2：http://www.amazon.com/s/ref=sr_pg_2?rh=i%3Aaps%2Ck%3Asamsung+appliances&page=2&keywords=samsung+appliances&ie=UTF8&qid=1391033912

编码：

hxs.select('//h3[@class="newaps"]/a/@href').extract()

预期产出：

对于上面我的代码的URL 1

我的预期输出是。

1.http://www.amazon.com/Samsung-RF4287-Refrigerator-Integrated-Stainless/dp/B003M5L284/ref=sr_1_2/189-7301776-6362144?ie=UTF8&qid=1391314328&sr=8-2&keywords=samsung+appliances


2. http://www.amazon.com/Samsung-RF4289HARS/dp/B004XQHBHC/ref=sr_1_3/189-7301776-6362144?ie=UTF8&qid=1391314328&sr=8-3&keywords=samsung+appliances


3.http://www.amazon.com/Samsung-DC47-00019A-Heating-Element/dp/B001ICYB2M/ref=sr_1_4/189-7301776-6362144?ie=UTF8&qid=1391314328&sr=8-4&keywords=samsung+appliances

etc......

我需要上面的代码，然后我也需要URL 2 ..

我需要BOth URL 1和URL 2的结果......

查看我的代码.........

    From scrapy.spider import BaseSpider      
    from scrapy.http import Request    
    from urlparse import urljoin        
    from scrapy.selector import HtmlXPathSelector    
    import inspect    
    from amazon.items import AmazonItem    

    class amzspider(BaseSpider):
        name="amz"    

        start_urls=["http://www.amazon.com/s/ref=sr_pg_2?rh=i%3Aaps%2Ck%3Asamsung+appliances&page=2&keywords=samsung+appliances&ie=UTF8&qid=1386153209"]
        print start_urls           

    def parse(self,response):

        hxs = HtmlXPathSelector(response)


        ul=hxs.select('//div/ul[@class="rsltGridList grey"]').extract()
        l=len(hxs.select('//h3[@class="newaps"]/a/@href').extract())

        x=[]

        x1=[]
        url1=[]
        for i in range(l):
            x1.append(hxs.select('//h3[@class="newaps"]/a/@href').extract()[i].encode('utf-8').strip())


        print "URl parsed"          

        for i in range(l):
            url1.append(urljoin(response.url, x1[i]))

        for i in range(l):
            if url1[i]:
                yield Request(url1[i], callback=self.parse_sub)     

        r=hxs.select('//a[@id="pagnNextLink"]/@href').extract()[0].encode('utf-8')

        if r:
            yield Request(urljoin(response.url, r), callback=self.parse)

    def parse_sub(self,response):
        print " sub callled"
        itm=[]
#       item = response.meta.get('item')
        item=AmazonItem()
        hxs = HtmlXPathSelector(response)