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Setting up a WebSocket server in Spring 4

I am developing a real-time notification system via WebSockets using Spring 4 .

The source code is as follows:

WebSocketConfig:

@Configuration
@EnableScheduling
@EnableWebSocketMessageBroker
public class WebSocketConfig extends AbstractWebSocketMessageBrokerConfigurer {

    @Override
    public void registerStompEndpoints(StompEndpointRegistry registry) {
        registry.addEndpoint("/lrt").withSockJS();
    }

    @Override
    public void configureMessageBroker(MessageBrokerRegistry registry) {
        registry.enableSimpleBroker("/queue/", "/topic/");
        registry.setApplicationDestinationPrefixes("/app");
    }

}

LRTStatusListener:

@Service
public class LRTStatusListener implements ApplicationListener<BrokerAvailabilityEvent>{

    private static final Logger LOG = LoggerFactory.getLogger(LRTStatusListener.class);
    private final static long LRT_ID = 1234567890;
    private final static String LRT_OWNER = "Walter White";
    private final LRTStatusGenerator lrtStatusGenerator = new LRTStatusGenerator(LRT_ID, LRT_OWNER);
    private final MessageSendingOperations<String> messagingTemplate;
    private AtomicBoolean brokerAvailable = new AtomicBoolean();

    @Autowired
    public LRTStatusListener(MessageSendingOperations<String> messagingTemplate) {
        this.messagingTemplate = messagingTemplate;
    }

    @Override
    public void onApplicationEvent(BrokerAvailabilityEvent event) {
        this.brokerAvailable.set(event.isBrokerAvailable());
    }

    @Scheduled(fixedDelay=2000)
    public void sendLRTStatus() {
        LRTStatus lrtStatus = this.lrtStatusGenerator.generateLRTStatus();
        if (LOG.isTraceEnabled())
            LOG.trace("Sending LRT status");
        if (this.brokerAvailable.get())
            this.messagingTemplate
                .convertAndSend("/topic/status" + lrtStatus.getLRTId(), lrtStatus);
    }

    // Random status generator
    private static class LRTStatusGenerator {

        private LRTStatus lrtStatus;

        public LRTStatusGenerator(long lrtId, String owner) {
            lrtStatus = new LRTStatus(lrtId, owner, getCurrentTimestamp(), generateLRTStatusMessage());
        }

        public LRTStatus generateLRTStatus() {
            lrtStatus.setMessage(generateLRTStatusMessage());
            return lrtStatus;
        }

        private String getCurrentTimestamp() {
            Date date = new Date();
            Timestamp timestamp = new Timestamp(date.getTime());
            return timestamp.toString();
        }

        private String generateLRTStatusMessage() {
            String statusMessage;
            switch ((int) Math.random() * 2) {
            case 1:
                statusMessage =
                        "HANK: What? You want me to beg? You're the smartest guy I ever met. " +
                        "And you're too stupid to see... he made up his mind ten minutes ago.";
                break;
            case 2:
                statusMessage =
                        "WALTER: That right. Now say my name. " +
                        "- DECLAN: ...You're Heisenberg. - WALTER: You're goddamn right.";
                break;
            default:
                statusMessage =
                        "WALTER: I am not in danger, Skyler. I am the danger! " +
                        "A guy opens his door and gets shot and you think that of me? " +
                        "No. I am the one who knocks!";
                break;
            }
            return statusMessage;
        }

    }

}

CheckLRTStatusController

@Controller
public class CheckLRTStatusController {

    @MessageExceptionHandler
    @SendToUser("/topic/errors")
    public String handleException(Throwable exception) {
        return exception.getMessage();
    }

}

The application simulates a long transaction status (LRT), changing its information every 2000 ms.

Now I am testing WebSocket by defining a client through SockJS :

<script src="http://cdn.sockjs.org/sockjs-0.3.min.js"></script>
<script>
    var sock = new SockJS('/lrt');
    sock.onopen = function() {
        console.log('open');
    };
    sock.onmessage = function(e) {
        console.log('message', e.data);
    };
    sock.onclose = function() {
        console.log('close');
    };
</script>

The connection is working fine, but I can not see the data stream.

How can I correctly configure my application to create and subsequently route messages sent by the WebSocket server on my client console?

, Message Broker .

+4
1

JavaScript-, ?

<script src="http://cdn.sockjs.org/sockjs-0.3.min.js"></script>
<script>
    var sock = new SockJS('/lrt');
    sock.onopen = function() {
        console.log('open');
    };
    sock.onmessage = function(e) {
        console.log('message', e.data);
    };
    sock.onclose = function() {
        console.log('close');
    };
</script>

SockJS, . .

:

registry.enableSimpleBroker("/queue/", "/topic/");

STOMP JavaScript ( SockJS), , :

stompClient.subscribe("/topic/status*", function(message) {
    ...
});

stompClient.subscribe("/queue/whatever", function(message) {
    ...
});

spring-websocket-portfolio .

+4

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