floehopper

require 'nokogiri'

response = get(sitemap_path)
doc = Nokogiri::XML(response.body)
namespace = 'http://www.sitemaps.org/schemas/sitemap/0.9'
locs = doc.xpath('//urlset:url//urlset:loc', 'urlset' => namespace)
urls = locs.map(&:text).map { |u| URI(u).path }.uniq