Spring Websocket STOMP：发送RECEIPT帧

Question

I have a Websocket-stomp server based on Spring and its SimpleBroker implementation (not utilizing an external broker).

I would like to enable STOMP RECEIPT messages.

How I could configure my code to send these automatically?

Answer 1

In Spring Integration test for the STOMP protocol we have this code:

    //SimpleBrokerMessageHandler doesn't support RECEIPT frame, hence we emulate it this way
    @Bean
    public ApplicationListener<SessionSubscribeEvent> webSocketEventListener(
            final AbstractSubscribableChannel clientOutboundChannel) {
        return event -> {
            Message<byte[]> message = event.getMessage();
            StompHeaderAccessor stompHeaderAccessor = StompHeaderAccessor.wrap(message);
            if (stompHeaderAccessor.getReceipt() != null) {
                stompHeaderAccessor.setHeader("stompCommand", StompCommand.RECEIPT);
                stompHeaderAccessor.setReceiptId(stompHeaderAccessor.getReceipt());
                clientOutboundChannel.send(
                        MessageBuilder.createMessage(new byte[0], stompHeaderAccessor.getMessageHeaders()));
            }
        };
    }

https://github.com/spring-projects/spring-integration/blob/master/spring-integration-stomp/src/test/java/org/springframework/integration/stomp/inbound/StompInboundChannelAdapterWebSocketIntegrationTests.java

Answer 2

A solution similar to the post of Artem Bilan using a separated class to implement the listener.

@Component
public class SubscribeListener implements ApplicationListener<SessionSubscribeEvent> {
    @Autowired
    AbstractSubscribableChannel clientOutboundChannel;

    @Override
    public void onApplicationEvent(SessionSubscribeEvent event) {
        Message<byte[]> message = event.getMessage();
        StompHeaderAccessor stompHeaderAccessor = StompHeaderAccessor.wrap(message);

        if (stompHeaderAccessor.getReceipt() != null) {
            StompHeaderAccessor receipt = StompHeaderAccessor.create(StompCommand.RECEIPT);
            receipt.setReceiptId(stompHeaderAccessor.getReceipt());    
            receipt.setSessionId(stompHeaderAccessor.getSessionId());
            clientOutboundChannel.send(MessageBuilder.createMessage(new byte[0], receipt.getMessageHeaders()));
        }
    }
}

Answer 3

The answer provided by Artem Bilan only works for SUBSCRIBE frames. Here is another one that captures any incoming frame with receipt header. Only the class with the @EnableWebSocketMessageBroker annotation needs to be extended, other classes (like the ones with @Controller annotation) remain the same.

 import java.util.logging.Level; import java.util.logging.Logger; import java.util.Map; import java.util.List; import java.util.HashMap; import java.util.ArrayList; import org.springframework.context.annotation.Configuration; import org.springframework.messaging.simp.config.MessageBrokerRegistry; import org.springframework.web.socket.config.annotation.AbstractWebSocketMessageBrokerConfigurer; import org.springframework.web.socket.config.annotation.EnableWebSocketMessageBroker; import org.springframework.web.socket.config.annotation.StompEndpointRegistry; import org.springframework.messaging.simp.config.SimpleBrokerRegistration; import org.springframework.messaging.Message; import org.springframework.messaging.MessageHeaders; import org.springframework.messaging.support.ChannelInterceptorAdapter; import org.springframework.messaging.support.GenericMessage; import org.springframework.messaging.simp.config.ChannelRegistration; import org.springframework.messaging.simp.SimpMessageType; import org.springframework.messaging.simp.stomp.StompCommand; import org.springframework.messaging.MessageChannel; import org.springframework.beans.factory.annotation.Autowired; @Configuration @EnableWebSocketMessageBroker public class WebSocketConfig extends AbstractWebSocketMessageBrokerConfigurer { private static final Logger LOGGER = Logger.getLogger( WebSocketConfig.class.getName() ); private MessageChannel outChannel; @Override public void configureClientInboundChannel(ChannelRegistration registration) { registration.interceptors( new InboundMessageInterceptor() ); } @Override public void configureClientOutboundChannel(ChannelRegistration registration) { registration.interceptors( new OutboundMessageInterceptor() ); } @Override public void configureMessageBroker(MessageBrokerRegistry config) { // prefixes are application-dependent config.enableSimpleBroker("/topic"); config.setApplicationDestinationPrefixes("/app"); } @Override public void registerStompEndpoints(StompEndpointRegistry registry) { registry.addEndpoint("/note"); } class InboundMessageInterceptor extends ChannelInterceptorAdapter { @SuppressWarnings("unchecked") public Message preSend(Message message, MessageChannel channel) { LOGGER.log( Level.SEVERE, "preSend: "+message ); GenericMessage genericMessage = (GenericMessage)message; MessageHeaders headers = genericMessage.getHeaders(); String simpSessionId = (String)headers.get( "simpSessionId" ); if( ( SimpMessageType.MESSAGE.equals( headers.get( "simpMessageType" ) ) && StompCommand.SEND.equals( headers.get( "stompCommand" ) ) ) || ( SimpMessageType.SUBSCRIBE.equals( headers.get( "simpMessageType" ) ) && StompCommand.SUBSCRIBE.equals( headers.get( "stompCommand" ) ) ) && ( simpSessionId != null ) ) { Map<String,List<String>> nativeHeaders = (Map<String,List<String>>)headers.get( "nativeHeaders" ); if( nativeHeaders != null ) { List<String> receiptList = nativeHeaders.get( "receipt" ); if( receiptList != null ) { String rid = (String)receiptList.get(0); LOGGER.log( Level.SEVERE, "receipt requested: "+rid ); sendReceipt( rid, simpSessionId ); } } } return message; } private void sendReceipt( String rid, String simpSessionId ) { if( outChannel != null ) { HashMap<String,Object> rcptHeaders = new HashMap<String,Object>(); rcptHeaders.put( "simpMessageType", SimpMessageType.OTHER ); rcptHeaders.put( "stompCommand", StompCommand.RECEIPT ); rcptHeaders.put( "simpSessionId", simpSessionId ); HashMap<String,List<String>> nativeHeaders = new HashMap<String,List<String>>(); ArrayList<String> receiptElements = new ArrayList<String>(); receiptElements.add( rid ); nativeHeaders.put( "receipt-id", receiptElements ); rcptHeaders.put( "nativeHeaders",nativeHeaders ); GenericMessage<byte[]> rcptMsg = new GenericMessage<byte[]>( new byte[0],new MessageHeaders( rcptHeaders ) ); outChannel.send( rcptMsg ); } else LOGGER.log( Level.SEVERE, "receipt NOT sent" ); } } class OutboundMessageInterceptor extends ChannelInterceptorAdapter { public void postSend(Message message, MessageChannel channel, boolean sent) { LOGGER.log( Level.SEVERE, "postSend: "+message ); outChannel = channel; } } } 

Indeed, it is much more complicated than it should be and obtaining the outChannel is not very elegant. But it works. :-)

Answer 4

all of the above send receipt frames too early. the following gets you what you need.

ref: https://github.com/spring-projects/spring-framework/issues/21848

@Configuration
static class WebSocketConfig implements WebSocketMessageBrokerConfigurer {

    private MessageChannel outChannel;

    @Autowired
    public WebSocketConfig(MessageChannel clientOutboundChannel) {
        this.outChannel = clientOutboundChannel;
    }

    @Override
    public void configureClientInboundChannel(ChannelRegistration registration) {

        registration.interceptors(new ExecutorChannelInterceptor() {

            @Override
            public void afterMessageHandled(Message<?> inMessage,
                    MessageChannel inChannel, MessageHandler handler, Exception ex) {

                StompHeaderAccessor inAccessor = StompHeaderAccessor.wrap(inMessage);
                String receipt = inAccessor.getReceipt();
                if (StringUtils.isEmpty(receipt)) {
                    return;
                }

                StompHeaderAccessor outAccessor = StompHeaderAccessor.create(StompCommand.RECEIPT);
                outAccessor.setSessionId(inAccessor.getSessionId());
                outAccessor.setReceiptId(receipt);
                outAccessor.setLeaveMutable(true);

                Message<byte[]> outMessage =
                        MessageBuilder.createMessage(new byte[0], outAccessor.getMessageHeaders());

                outChannel.send(outMessage);
            }
        });
    }
}