Akka-Http Web Socket how to send multiple response to a client

Question
1

Hi, I want to design a web-socket to get a message from the user and keeping the connection, send multiple message to the server (for example the server side will establish a connection to the mMQTT message broker and consume messages and send them to the client continuously).
Using the Akka-http I developed the following:

def echoService() Flow[Message, Message, _] = Flow[Message].map{
  case TextMessage.Strict(txt) =>
    val temp = password.split("/")
    if (temp.nonEmpty && temp.length < 4) {
      val persistence = new MemoryPersistence
      val client = new MqttClient(url, MqttClient.generateClientId(), persistence)
      val MQtt_Option: MqttConnectOptions = new MqttConnectOptions
      MQtt_Option.setCleanSession(true)
      MQtt_Option.setUserName(userName)
      MQtt_Option.setPassword(password.toCharArray)
      client.setCallback(
        new MqttCallback() {
        override def connectionLost(cause: Throwable): Unit = {

        }
        @throws[Exception]
        override def messageArrived(topic: String, message: MqttMessage): Unit = {
          TextMessage(message.getPayload.toString)
        }

        override def deliveryComplete(token: IMqttDeliveryToken): Unit = {
        }
      })
      client.connect(MQtt_Option)
      client.subscribe(txt)
    }
    TextMessage("")
}

val websocketRoute = get {
      handleWebSocketMessages(echoService())
    }

But it just receive a message and send just one message and then disconnect! I found out that is behavior of the Flow object but I don’t know how should I change mu code to receive just one message from the client and send client continuously the message broker messages!

Any help or suggestion would be appreciated!

2

This actually isn’t the best place for this question – we’re mostly focused on the language per se here. But there is a similar forum specifically for Akka, which is more likely to have folks who can help: I’d recommend asking this over there…

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