How to use stop_server method of Selenium.WebDriver Package

...21    # responsible for starting and stopping driver implementations.22    #23    # Subclasses must implement the following private methods:24    #   * #start_process25    #   * #stop_server26    #   * #cannot_connect_error_text27    #28    # @api private29    #30    class Service31      START_TIMEOUT       = 2032      SOCKET_LOCK_TIMEOUT = 4533      STOP_TIMEOUT        = 2034      @executable = nil35      @missing_text = nil36      class << self37        attr_reader :executable, :missing_text38      end39      attr_accessor :host40      def initialize(executable_path, port, driver_opts)41        @executable_path = binary_path(executable_path)42        @host            = Platform.localhost43        @port            = Integer(port)44        @extra_args      = extract_service_args(driver_opts)45        raise Error::WebDriverError, "invalid port: #{@port}" if @port < 146      end47      def binary_path(path)48        path = Platform.find_binary(self.class.executable) if path.nil?49        raise Error::WebDriverError, self.class.missing_text unless path50        Platform.assert_executable path51        path52      end53      def start54        if process_running?55          raise "already started: #{uri.inspect} #{@executable_path.inspect}"56        end57        Platform.exit_hook { stop } # make sure we don't leave the server running58        socket_lock.locked do59          find_free_port60          start_process61          connect_until_stable62        end63      end64      def stop65        stop_server66        @process.poll_for_exit STOP_TIMEOUT67      rescue ChildProcess::TimeoutError68      ensure69        stop_process70      end71      def uri72        @uri ||= URI.parse("http://#{@host}:#{@port}")73      end74      private75      def build_process(*command)76        WebDriver.logger.debug("Executing Process #{command}")77        @process = ChildProcess.build(*command)78        if WebDriver.logger.debug?79          @process.io.stdout = @process.io.stderr = WebDriver.logger.io80        elsif Platform.jruby?81          # Apparently we need to read the output of drivers on JRuby.82          @process.io.stdout = @process.io.stderr = File.new(Platform.null_device, 'w')83        end84        @process85      end86      def connect_to_server87        Net::HTTP.start(@host, @port) do |http|88          http.open_timeout = STOP_TIMEOUT / 289          http.read_timeout = STOP_TIMEOUT / 290          yield http91        end92      end93      def find_free_port94        @port = PortProber.above(@port)95      end96      def start_process97        raise NotImplementedError, 'subclass responsibility'98      end99      def stop_process100        return if process_exited?101        @process.stop STOP_TIMEOUT102        @process.io.stdout.close if Platform.jruby? && !WebDriver.logger.debug?103      end104      def stop_server105        return if process_exited?106        connect_to_server { |http| http.get('/shutdown') }107      end108      def process_running?109        defined?(@process) && @process && @process.alive?110      end111      def process_exited?112        @process.nil? || @process.exited?113      end114      def connect_until_stable115        socket_poller = SocketPoller.new @host, @port, START_TIMEOUT116        return if socket_poller.connected?117        raise Error::WebDriverError, cannot_connect_error_text118      end...

...12          ffi_lib WebDriver::IE::DLLS[:win32]13        end14        ffi_convention :stdcall15        attach_function :start_server,  :StartServer,           [:int],     :pointer16        attach_function :stop_server,   :StopServer,            [:pointer], :void17        attach_function :session_count, :GetServerSessionCount, [],         :int18        attach_function :current_port,  :GetServerPort,         [],         :int19        attach_function :is_running,    :ServerIsRunning,       [],         :bool20        def initialize21          @handle = nil22        end23        #24        # Starts the server, communicating on the specified port, if it is not already running25        #26        def start(start_port, timeout)27          return port if running?28          @handle = self.class.start_server(start_port)29          unless SocketPoller.new(Platform.localhost, start_port, timeout).connected?30            raise Error::WebDriverError, "unable to connect to IE server within #{timeout} seconds"31          end32          start_port33        end34        def stop35          return if session_count != 0 || @handle.nil?36          self.class.stop_server @handle37          @handle = nil38        end39        def running?40          self.class.is_running41        end42        def port43          self.class.current_port44        end45        def uri46          "http://#{Platform.localhost}:#{port}"47        end48        private49        def session_count50          self.class.session_count...

...12          ffi_lib WebDriver::IE::DLLS[:win32]13        end14        ffi_convention :stdcall15        attach_function :start_server,  :StartServer,           [:int],     :pointer16        attach_function :stop_server,   :StopServer,            [:pointer], :void17        attach_function :session_count, :GetServerSessionCount, [],         :int18        attach_function :current_port,  :GetServerPort,         [],         :int19        attach_function :is_running,    :ServerIsRunning,       [],         :bool20        def initialize21          @handle = nil22        end23        #24        # Starts the server, communicating on the specified port, if it is not already running25        #26        def start(start_port)27          return port if running?28          @handle = self.class.start_server(start_port)29          start_port30        end31        def stop32          return if session_count != 0 || @handle.nil?33          self.class.stop_server @handle34          @handle = nil35        end36        def running?37          self.class.is_running38        end39        def port40          self.class.current_port41        end42        private43        def session_count44          self.class.session_count45        end46      end # Server47    end # IE...

1  (unknown error: DevToolsActivePort file doesn't exist)2  (The process started from chrome location C:\Users\DELL\AppData\Local\Google\Chrome\Application\chrome.exe is no longer running, so ChromeDriver is assuming that Chrome has crashed.)3  (Driver info: chromedriver=2.28.455506 (1b8e8d2e2e2d1e9b9c8b8b0f7d2e3d2b2c2b8c3),platform=Windows NT 6.1.7601 SP1 x86_64) (Selenium::WebDriver::Error::UnknownError)