http con cache

      response = begin
        uri = URI.parse(uri)
        Timeout::timeout(@timeout) {
          http = Net::HTTP.new(uri.host, uri.port)

          if uri.scheme == 'https'
            http.use_ssl = true
            http.verify_mode = OpenSSL::SSL::VERIFY_NONE
          end

          http.start {
            request = Net::HTTP::Get.new(uri.request_uri)
            request['If-None-Match'] ||=  cache['Etag']
            request['If-Modified-Since'] ||=  cache['Last-Modified']
            request['USER-Agent'] = 'CodeAR 1.2'
            request['Accept-Encoding'] = 'gzip, deflate'
            http.request(request)
          }
        }
      rescue Timeout::Error => error
        Net::HTTPRequestTimeOut.new '1.1', '408', error.to_s
      rescue SocketError, Errno::ECONNRESET => error
        Net::HTTPInternalServerError.new '1.1', '500', error.to_s
      end