require 'uri'
url =~ URI::regexp
# => 0 if it match, nil if not

require "net/http"
def url_exist? url_string Timeout.timeout 3 do	# set timeout 3s because some invalid url take long time to respond url = URI.parse url_string new_url = url.scheme || "http://#{url_string}" url = URI.parse new_url if url.scheme.nil? req = Net::HTTP.new url.host, url.port req.use_ssl = url.scheme == 'https' path = url.path if url.path.present? res = req.request_head(path || '/') res.code != "404" end
rescue false
end