import com.github.andyglow.websocket._

  // 1. prepare ws-client
  // 2. define message handler
  val cli = WebsocketClient[String]("ws://echo.websocket.org") {
    case str =>
      logger.info(s"<<| $str")
  }

  // 4. open websocket
  val ws = cli.open()

  // 5. send messages
  ws ! "hello"
  ws ! "world"

  // define some mutex to be able to shutdown app when message passing ends 
  val semaphore = new Semaphore(0)
  
  // define our protocol handler
  val protocolHandler = new WebsocketHandler[String]() {
    def receive = {
      case str if str startsWith "repeat " =>
        sender() ! "repeating " + str.substring(7)
        logger.info(s"<<| $str")

      case str if str endsWith "close" =>
        logger.info(s"<<! $str")
        sender().close
        semaphore.release()

      case str =>
        logger.info(s"<<| $str")
    }
  }

  // create websocket client and open connection
  val cli = WebsocketClient(Uri("ws://echo.websocket.org"), protocolHandler)
  val ws = cli.open()

  // send some messages
  ws ! "hello"
  ws ! "world"
  ws ! "repeat and close"
  
  // wait for echoed 'repeating close'
  semaphore.acquire(1)
  
  // shutdown whole the netty stack
  cli.shutdownSync()