check_auth (OpenID::Consumer::IdResHandler)

    # File lib/openid/consumer/idres.rb, line 227
          def check_auth
            Util.log("Using 'check_authentication' with #{server_url}")
            begin
              request = create_check_auth_request
            rescue Message::KeyNotFound => why
              raise ProtocolError, "Could not generate 'check_authentication' "\
                                   "request: #{why.message}"
            end

            response = OpenID.make_kv_post(request, server_url)

            process_check_auth_response(response)
          end