杂乱无章，只跟踪内部网址，但提取所有找到的链接

Question

我想得到所有外部链接从一个给定的网站使用剪贴。蜘蛛还使用以下代码爬行外部链接：

from scrapy.contrib.spiders import CrawlSpider, Rule
from scrapy.contrib.linkextractors import LinkExtractor
from myproject.items import someItem

class someSpider(CrawlSpider):
  name = 'crawltest'
  allowed_domains = ['someurl.com']
  start_urls = ['http://www.someurl.com/']

  rules = (Rule (LinkExtractor(), callback="parse_obj", follow=True),
  )

  def parse_obj(self,response):
    item = someItem()
    item['url'] = response.url
    return item

我错过了什么？“允许的域”是否阻止对外部链接进行爬网？如果我为LinkExtractor设置“允许域”，则不会提取外部链接。只是澄清一下：我不想抓取内部链接，而是提取外部链接。任何帮助通知！

Answer 1

根据12Ryan12的答案更新的代码

from scrapy.spiders import CrawlSpider, Rule
from scrapy.linkextractors.lxmlhtml import LxmlLinkExtractor
from scrapy.item import Item, Field

class MyItem(Item):
    url= Field()


class someSpider(CrawlSpider):
    name = 'crawltest'
    allowed_domains = ['someurl.com']
    start_urls = ['http://www.someurl.com/']
    rules = (Rule(LxmlLinkExtractor(allow=()), callback='parse_obj', follow=True),)

    def parse_obj(self,response):
        item = MyItem()
        item['url'] = []
        for link in LxmlLinkExtractor(allow=(),deny = self.allowed_domains).extract_links(response):
            item['url'].append(link.url)
        return item