def parse(self, response):
    sel = Selector(response)
    links = sel.xpath(AirportSelectors.LIST_AIRPORTS).extract()
    current_page = long(response.meta.get('current_page') or 1)
    print u'links: %s, %s' % (len(links), response.url)

    if links:
      for link in links:
        canonical = u'%s%s' % (self.base_url, link.split('?')[0])
        if LocationAirportEs.check_by_url(canonical):
          continue
        request = Request(canonical, callback=self.parse_airport, errback=self.parse_err)
        request.meta['page_kind'] = 'airport'
        yield request
      if len(links) >= 100:
        next_page = u'%s?pageid=%s' % (response.url.split('?')[0], current_page + 1)
        request = Request(next_page, callback=self.parse, errback=self.parse_err)
        request.meta['page_kind'] = 'list'
        request.meta['current_page'] = current_page + 1
        yield request