Connecting to a websocket in Java

Question

I am trying to connect to the web socket wss://ws-feed.gdax.com

I have got this working in JavaScript (See here) but I am trying to move the connection Server side into my Spring Boot app.

So far I have:

@SpringBootApplication
public class DemoApplication implements CommandLineRunner {

    private Logger LOG = LoggerFactory.getLogger(DemoApplication.class);

    public static void main(String[] args) {
        SpringApplication.run(DemoApplication.class, args);
    }

    @Override
    public void run(String... args) throws Exception {
        WebSocketContainer container = ContainerProvider.getWebSocketContainer();
        container.setDefaultMaxTextMessageBufferSize(64*1024);
        WebSocketClient simpleWebSocketClient = new StandardWebSocketClient(container);
        List<Transport> transports = new ArrayList<>(1);
        transports.add(new WebSocketTransport(simpleWebSocketClient));
        SockJsClient sockJsClient = new SockJsClient(transports);
        WebSocketStompClient stompClient = new WebSocketStompClient(sockJsClient);
        stompClient.setMessageConverter(new MappingJackson2MessageConverter());

        LOG.info("Connecting To [wss://ws-feed.gdax.com]");
        StompSession session = stompClient.connect("wss://ws-feed.gdax.com", new GDAXHandler()).get();
    }

    private class GDAXHandler extends WebSocketHttpHeaders implements StompSessionHandler {

        @Override
        public void afterConnected(StompSession session, StompHeaders connectedHeaders) {
            LOG.info("Connected");
            String payload = "{\"type\": \"subscribe\",\"channels\":[{\"name\": \"ticker\",\"product_ids\": [\"ETH-EUR\"]}]\"}";
            LOG.info("Sending [" + payload + "]");
            session.send("/", payload);
        }

        @Override
        public void handleException(StompSession session, StompCommand command, StompHeaders headers, byte[] payload, Throwable exception) {
            LOG.error("Exception", exception);
        }

        @Override
        public void handleTransportError(StompSession session, Throwable exception) {
            LOG.error("Transport Error", exception);
        }

        @Override
        public Type getPayloadType(StompHeaders headers) {
            return String.class;
        }

        @Override
        public void handleFrame(StompHeaders headers, Object payload) {
            LOG.info("Frame [" + payload + "]");
        }
    }
}

If I run this app the output is:

INFO Tomcat started on port(s): 8080 (http)

INFO Connecting To [wss://ws-feed.gdax.com]

INFO Error starting ApplicationContext. To display the auto-configuration report re-run your application with 'debug' enabled.

ERROR Transport Error org.springframework.messaging.simp.stomp.ConnectionLostException: Connection closed

Caused by: org.springframework.messaging.simp.stomp.ConnectionLostException: Connection closed at org.springframework.messaging.simp.stomp.DefaultStompSession.afterConnectionClosed(DefaultStompSession.java:487) ~[spring-messaging-4.3.13.RELEASE.jar:4.3.13.RELEASE] at org.springframework.web.socket.messaging.WebSocketStompClient$WebSocketTcpConnectionHandlerAdapter.afterConnectionClosed(WebSocketStompClient.java:354) ~[spring-websocket-4.3.13.RELEASE.jar:4.3.13.RELEASE] at org.springframework.web.socket.sockjs.client.AbstractClientSockJsSession.afterTransportClosed(AbstractClientSockJsSession.java:324) ~[spring-websocket-4.3.13.RELEASE.jar:4.3.13.RELEASE] at org.springframework.web.socket.sockjs.client.WebSocketTransport$ClientSockJsWebSocketHandler.afterConnectionClosed(WebSocketTransport.java:172) ~[spring-websocket-4.3.13.RELEASE.jar:4.3.13.RELEASE] ...

It never even makes it to the Connected state. What am I doing wrong?

Answer 1

The solution (thanks to @ArtemBilan) was to get rid of STOMP and use a basic Web Socket e.g.

@SpringBootApplication
public class DemoApplication implements CommandLineRunner {

    private Logger LOG = LoggerFactory.getLogger(DemoApplication.class);

    public static void main(String[] args) {
        SpringApplication.run(DemoApplication.class, args);
    }

    @Override
    public void run(String... args) {
        LOG.info("Connecting To [wss://ws-feed.gdax.com]");
        WebSocketConnectionManager connectionManager = new WebSocketConnectionManager(new StandardWebSocketClient(), new GDAXWebSocketHandler(), "wss://ws-feed.gdax.com");
        connectionManager.start();
    }

    private class GDAXWebSocketHandler extends TextWebSocketHandler {

        @Override
        public void handleTextMessage(WebSocketSession session, TextMessage message) {
            LOG.info("Message Received [" + message.getPayload() + "]");
        }

        @Override
        public void afterConnectionEstablished(WebSocketSession session) throws Exception {
            LOG.info("Connected");
            String payload = "{\"type\": \"subscribe\",\"channels\":[{\"name\": \"ticker\",\"product_ids\": [\"ETH-EUR\"]}]}";
            LOG.info("Sending [" + payload + "]");
            session.sendMessage(new TextMessage(payload));
        }

        @Override
        public void handleTransportError(WebSocketSession session, Throwable exception) {
            LOG.error("Transport Error", exception);
        }

        @Override
        public void afterConnectionClosed(WebSocketSession session, CloseStatus status){
            LOG.info("Connection Closed [" + status.getReason() + "]");
        }
    }
}

Output log:

INFO Tomcat started on port(s): 8080 (http)

INFO Connecting To [wss://ws-feed.gdax.com]

INFO Starting WebSocketConnectionManager

INFO Connecting to WebSocket at wss://ws-feed.gdax.com

INFO Started DemoApplication in 2.324 seconds (JVM running for 3.076)

INFO Connected

INFO Sending [{"type": "subscribe","channels":[{"name": "ticker","product_ids": ["ETH-EUR"]}]}]

INFO Successfully connected

INFO Message Received [{"type":"ticker","sequence":569701928,"product_id":"ETH-EUR","price":"641.65000000","open_24h":"465.26000000","volume_24h":"100991.88666517","low_24h":"641.65000000","high_24h":"657.17000000","volume_30d":"1129037.16627038","best_bid":"641.59","best_ask":"641.65"}]

INFO Message Received [{"type":"subscriptions","channels":[{"name":"ticker","product_ids":["ETH-EUR"]}]}]

INFO Message Received [{"type":"ticker","sequence":569702018,"product_id":"ETH-EUR","price":"641.65000000","open_24h":"465.26000000","volume_24h":"100969.00195695","low_24h":"641.65000000","high_24h":"657.17000000","volume_30d":"1129014.28156216","best_bid":"641.64","best_ask":"641.73","side":"buy","time":"2018-02-07T09:07:49.556000Z","trade_id":2980644,"last_size":"1.00879065"}]