Where the STOMP ACK frame goes to in RabbitMQ? - spring

Question

I have an app where I send messages over Stomp subscriptions. When messages are received, they send ACK frame. I'd like to handle this ack frame on server side, and my question is there any ack listener in rabbitmq or ack handler that will takes that frame and its headers? I'd like to access that frame to send some kind of confirmation to the producer that message was received.
stompClient.subscribe('/topic/'+ thread, function (greeting) {
var divId = "#userinfo";
console.log("SENDING TO TOPIC/GREETING")
showGreeting(divId, JSON.parse(greeting.body).person,
JSON.parse(greeting.body).message);
greeting.ack();
}, {id: thread, ack:'client'});
#MessageMapping("/message")
public MessageTemplate send(MessageTemplate messageTemp) throws Exception {
MessageTemplate message = new MessageTemplate(messageTemp.getPerson(), messageTemp.getMessage(), messageTemp.getTo());
rabbitTemplate.convertAndSend("amq.topic", messageTemp.getTo(), message);
return message;
}
<<< MESSAGE
subscription:other
destination:/topic/other
message-id:T_other##session-8-X11WtIiVQr-7UcONamng##3
redelivered:false
__TypeId__:com.patrykmaryn.spring.second.springsecond.MessageTemplate
priority:0
persistent:true
content-encoding:UTF-8
content-type:application/json
content-length:46
>>> ACK
message-id:T_other##session-8-X11WtIiVQr-7UcONamng##3
subscription:other
EDIT
I thought I could use
#Override
public void configureClientInboundChannel(ChannelRegistration registration) {
registration.interceptors(inBoundInterceptor);
}
And then in
public class InboundMessagesChannelInterceptor implements ChannelInterceptor {
#Override
public Message<?> preSend(Message<?> message, MessageChannel messageChannel) {
// here's some logic to do with ACK frame like sending a
// notifiction message to the sender
return message;
}
}
However the method intercepts each inbound event, but I'd need only ACK message. In this case how could I get the ACK frame headers only?

Answer 1

The STOMP protocol has no support for telling a sender that their message has been acknowledged therefore you're going to need to implement your solution at the application level rather than at the protocol level. You can do this by implementing a request/response pattern in your sender and consumer.
This will, of course, significantly increase the amount of communication which your clients conduct which could potentially limit your application's scalability, but there's no way to avoid the communication overhead if you want this functionality with STOMP.