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Spring broadcast message to users via private channel

I'm struggling how to send message to all users in a private channel in Spring. Here is my WebSocket config class:
#Configuration
#EnableWebSocketMessageBroker
public class WebSocketConfig implements WebSocketMessageBrokerConfigurer {
#Override
public void configureMessageBroker(MessageBrokerRegistry config) {
config.enableSimpleBroker("/all", "/message","/topic");
config.setUserDestinationPrefix("/secured/user");
config.setApplicationDestinationPrefixes("/app");
}
#Override
public void registerStompEndpoints(StompEndpointRegistry registry) {
registry.addEndpoint("/ws");
registry.addEndpoint("/ws")
.setHandshakeHandler(new UserHandshakeHandler())
.withSockJS();
}
}
Then I have a list of all my usernames, so I loop my list to send each of them a private message, like this:
#Service
#Slf4j
public class MessageService {
private final SimpMessagingTemplate simpMessagingTemplate;
public MessageService(SimpMessagingTemplate simpMessagingTemplate) {
this.simpMessagingTemplate = simpMessagingTemplate;
}
#Async
#Scheduled(fixedDelay = 1000, initialDelay = 1000)
public void sendMessageToUser() {
List<String> nameList = Lists.newArrayList("admin", "user");
for(String username : nameList){
simpMessagingTemplate.convertAndSendToUser(username,"/message", "Hello "+username);
}
}
}
Then in my web frontend, I setup a websocket connection like this:
function connect() {
const socket = new SockJS('/ws');
stompClient = Stomp.over(socket);
stompClient.connect({}, function (frame) {
console.log('Connected: ' + frame);
stompClient.subscribe('/secured/user/message',
function (message) {
console.log(message);
});
});
}
I got confirmation that frontend successfully establish the websocket connection:
Opening Web Socket...
stomp.min.js:8 Web Socket Opened...
stomp.min.js:8 >>> CONNECT
accept-version:1.1,1.0
heart-beat:10000,10000
stomp.min.js:8 <<< CONNECTED
version:1.1
heart-beat:0,0
user-name:admin
stomp.min.js:8 connected to server undefined
message.js:18 Connected: CONNECTED
user-name:admin
heart-beat:0,0
version:1.1
stomp.min.js:8 >>> SUBSCRIBE
id:sub-0
destination:/secured/user/message
The problem is the message is indeed sent from server side, but simply not able to be received in the frontend.
Hugely appreciate if anyone could help spot the issue in my code. Thanks a lot!

Sending triggers to client using websockets in spring boot and angular

I want to initiate a trigger(maybe a notification) from backend(based in spring boot) to a particular user whose userId is xyz.
the one way i have found is:
initially i connect to a websocket end point and subscribe to channel "/user/Notifications/xyz"
following is the relevant code in my angular typescript
connectToUserWebSocket(userId) {
let socket = new SockJS('http://localhost:5000/fellowGenius');
this.ws = Stomp.over(socket);
let that = this;
this.ws.connect(
{},
(frame) => {
that.ws.subscribe('/user/Notifications/' +userId, (message) => {
console.log("user subscribed");
});
},
(error) => {
alert('STOMP error ' + error);
}
);
}
Now once i have subscribed to my channel . I want to send a trigger to client which is initiated by backend itself so i run a code in my java service.
My relevant java code is:
#SendTo("/user/Notifications/{userId}")
public String sendMeetingNotificationWebSocket(#DestinationVariable String userId) {
return "hello";
}
my websocket configurations are:
#Configuration
#EnableWebSocketMessageBroker
public class WebSocketConfig implements WebSocketMessageBrokerConfigurer{
#Override
public void registerStompEndpoints(StompEndpointRegistry registry) {
registry.addEndpoint("/fellowGenius").setAllowedOrigins("*").addInterceptors(new HttpSessionHandshakeInterceptor()).withSockJS();
}
#Override
public void configureMessageBroker(MessageBrokerRegistry config) {
config.enableSimpleBroker("/inbox/","/user/Notifications/");
}
}
But the problem is that even i can see one web socket connected in my spring boot console.
But i don't get a response from the function on the client side.
Please help me with this problem.

How to publish event to angular js 1.4 from spring boot

Scenario:
Client(angular js 1.4) will call Rest endpoint to get data, the server(spring boot) will process the list of files and will return accurate data. To process the list of files, the server will take time depending on the number of files. so I have implements STOMP notification as to send a notification to the client saying "List of files have been processed and here is the bunch of files(result)".
Issue:
Stomp connection is established successfully and client also gets subscribed, but when the server publishes the events, client is not able to receive.
Below is my code snippet:
WebSocketConfig.java
#Configuration
#EnableWebSocketMessageBroker
public class WebSocketConfig implements WebSocketMessageBrokerConfigurer {
#Override
public void registerStompEndpoints(StompEndpointRegistry registry) {
registry.addEndpoint("/ws").withSockJS();
}
#Override
public void configureMessageBroker(MessageBrokerRegistry registry) {
registry.setApplicationDestinationPrefixes("/app");
registry.enableSimpleBroker("/topic"); // Enables a simple in-memory broker
}
}
SocketController.java
#Controller
public class SocketController {
#SendTo("/topic/public")
public String sendMessage() {
LOGGER.info("====> chatMessage()");
return "List updated successfully";
}
}
main.js
connect() {
var socket = new SockJS('/ws');
var stompClient = Stomp.over(socket);
event.preventDefault();
console.log("socket: ", socket);
console.log("stompClient: ", stompClient);
stompClient.connect({}, function (frame) {
console.log('Connected: ' + frame);
stompClient.subscribe('/topic/public', function (payload) {
console.log("payload: ", payload);
var message = JSON.parse(payload.body);
console.log("message: ", message);
});
}, function (error) {
console.log("onError() called");
console.log("error: ",error);
});
};
Scripts used:
<script src="https://cdnjs.cloudflare.com/ajax/libs/sockjs-client/1.1.4/sockjs.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/stomp.js/2.3.3/stomp.min.js"></script>
connect() method of main.js is called on button click. Probably there is an issue regarding scope I guess.

Use SimpMessagingTemplate to convert and send messages to the specific topic.
#Controller
public class SocketController {
private static final Logger LOGGER = LoggerFactory.getLogger(SocketController.class);
#Autowired private SimpMessagingTemplate template;
public void sendMessage(String message) {
LOGGER.info("====> sendMessage:");
this.template.convertAndSend("/topic/public", message);
}
}

Spring+WebSocket+STOMP. Message to specific session (NOT user)

I am trying to set up basic message broker on Spring framework, using a recipe I found here
Author claims it has worked well, but I am unable to receive messages on client, though no visible errors were found.
Goal:
What I am trying to do is basically the same - a client connects to server and requests some async operation. After operation completes the client should receive an event. Important note: client is not authenticated by Spring, but an event from async back-end part of the message broker contains his login, so I assumed it would be enough to store concurrent map of Login-SessionId pairs for sending messages directly to particular session.
Client code:
//app.js
var stompClient = null;
var subscription = '/user/queue/response';
//invoked after I hit "connect" button
function connect() {
//reading from input text form
var agentId = $("#agentId").val();
var socket = new SockJS('localhost:5555/cti');
stompClient = Stomp.over(socket);
stompClient.connect({'Login':agentId}, function (frame) {
setConnected(true);
console.log('Connected to subscription');
stompClient.subscribe(subscription, function (response) {
console.log(response);
});
});
}
//invoked after I hit "send" button
function send() {
var cmd_str = $("#cmd").val();
var cmd = {
'command':cmd_str
};
console.log("sending message...");
stompClient.send("/app/request", {}, JSON.stringify(cmd));
console.log("message sent");
}
Here is my configuration.
//message broker configuration
#Configuration
#EnableWebSocketMessageBroker
public class WebSocketConfig extends AbstractWebSocketMessageBrokerConfigurer{
#Override
public void configureMessageBroker(MessageBrokerRegistry config) {
/** queue prefix for SUBSCRIPTION (FROM server to CLIENT) */
config.enableSimpleBroker("/topic");
/** queue prefix for SENDING messages (FROM client TO server) */
config.setApplicationDestinationPrefixes("/app");
}
#Override
public void registerStompEndpoints(StompEndpointRegistry registry) {
registry
.addEndpoint("/cti")
.setAllowedOrigins("*")
.withSockJS();
}
}
Now, after basic config I should implement an application event handler to provide session-related information on client connect.
//application listener
#Service
public class STOMPConnectEventListener implements ApplicationListener<SessionConnectEvent> {
#Autowired
//this is basically a concurrent map for storing pairs "sessionId - login"
WebAgentSessionRegistry webAgentSessionRegistry;
#Override
public void onApplicationEvent(SessionConnectEvent event) {
StompHeaderAccessor sha = StompHeaderAccessor.wrap(event.getMessage());
String agentId = sha.getNativeHeader("Login").get(0);
String sessionId = sha.getSessionId();
/** add new session to registry */
webAgentSessionRegistry.addSession(agentId,sessionId);
//debug: show connected to stdout
webAgentSessionRegistry.show();
}
}
All good so far. After I run my spring webapp in IDE and connected my "clients" from two browser tabs I got this in IDE console:
session_id / agent_id
-----------------------------
|kecpp1vt|user1|
|10g5e10n|user2|
-----------------------------
Okay, now let's try to implement message mechanics.
//STOMPController
#Controller
public class STOMPController {
#Autowired
//our registry we have already set up earlier
WebAgentSessionRegistry webAgentSessionRegistry;
#Autowired
//a helper service which I will post below
MessageSender sender;
#MessageMapping("/request")
public void handleRequestMessage() throws InterruptedException {
Map<String,String> params = new HashMap(1);
params.put("test","test");
//a custom object for event, not really relevant
EventMessage msg = new EventMessage("TEST",params);
//send to user2 (just for the sake of it)
String s_id = webAgentSessionRegistry.getSessionId("user2");
System.out.println("Sending message to user2. Target session: "+s_id);
sender.sendEventToClient(msg,s_id);
System.out.println("Message sent");
}
}
A service to send messages from any part of the application:
//MessageSender
#Service
public class MessageSender implements IMessageSender{
#Autowired
WebAgentSessionRegistry webAgentSessionRegistry;
#Autowired
SimpMessageSendingOperations messageTemplate;
private String qName = "/queue/response";
private MessageHeaders createHeaders(String sessionId) {
SimpMessageHeaderAccessor headerAccessor = SimpMessageHeaderAccessor.create(SimpMessageType.MESSAGE);
headerAccessor.setSessionId(sessionId);
headerAccessor.setLeaveMutable(true);
return headerAccessor.getMessageHeaders();
}
#Override
public void sendEventToClient(EventMessage event,String sessionId) {
messageTemplate.convertAndSendToUser(sessionId,qName,event,createHeaders(sessionId));
}
}
Now, let's try to test it. I run my IDE, opened Chrome and created 2 tabs form which I connected to server. User1 and User2. Result console:
session_id / agent_id
-----------------------------
|kecpp1vt|user1|
|10g5e10n|user2|
-----------------------------
Sending message to user2. Target session: 10g5e10n
Message sent
But, as I mentioned in the beginning - user2 got absolutely nothing, though he is connected and subscribed to "/user/queue/response". No errors either.
A question is, where exactly I am missing the point? I have read many articles on the subject, but to no avail.
SPR-11309 says it's possible and should work. Maybe, id-s aren't actual session id-s?
And well maybe someone knows how to monitor if the message actually has been sent, not dropped by internal Spring mechanics?
SOLUTION UPDATE:
A misconfigured bit:
//WebSocketConfig.java:
....
#Override
public void configureMessageBroker(MessageBrokerRegistry config) {
/** queue prefix for SUBSCRIPTION (FROM server to CLIENT) */
// + parameter "/queue"
config.enableSimpleBroker("/topic","/queue");
/** queue prefix for SENDING messages (FROM client TO server) */
config.setApplicationDestinationPrefixes("/app");
}
....
I've spent a day debugging internal spring mechanics to find out where exactly it goes wrong:
//AbstractBrokerMessageHandler.java:
....
protected boolean checkDestinationPrefix(String destination) {
if ((destination == null) || CollectionUtils.isEmpty(this.destinationPrefixes)) {
return true;
}
for (String prefix : this.destinationPrefixes) {
if (destination.startsWith(prefix)) {
//guess what? this.destinationPrefixes contains only "/topic". Surprise, surprise
return true;
}
}
return false;
}
....
Although I have to admit I still think the documentation mentioned that user personal queues aren't to be configured explicitly cause they "already there". Maybe I just got it wrong.

Overall it looks good, but could you change from
config.enableSimpleBroker("/topic");
to
config.enableSimpleBroker("/queue");
... and see if this works? Hope this help.

WebSocket with Sockjs & Spring 4 but without Stomp

Is there a way to use WebSockets with SockJS client and Spring 4 server but not using STOMP?
Based on this tutorial from Spring's website, I know how to set up a WebSocket based application using Stomp and Spring 4. On the client side, we have:
var socket = new SockJS('/hello');
stompClient = Stomp.over(socket);
stompClient.connect({}, function(frame) {
setConnected(true);
console.log('Connected: ' + frame);
stompClient.subscribe('/topic/greetings', function(greeting){
showGreeting(JSON.parse(greeting.body).content);
});
});
And on the server side, we have the following in the controller:
#MessageMapping("/hello")
#SendTo("/topic/greetings")
public Greeting greeting(HelloMessage message) throws Exception {
Thread.sleep(3000); // simulated delay
return new Greeting("Hello, " + message.getName() + "!");
}
Now, I understand that #MessageMapping("/hello") ensures that if a message is sent to a destination "/hello", then the greeting() method will be called. And since the stompClient is subscribed to "/topic/greetings", the #SendTo("/topic/greetings") will send the message back to the stompClient.
But the problem with the above is that stompClient is a Stomp object. And I want to simply use sock.send('test'); and have it delivered to my server's destination. And I want to do #SendTo("myownclientdestinationmap"), I can receive it by
sock.onmessage = function(e) {
console.log('message', e.data);
};
So, any way to do this with Spring 4, SockJS and without Stomp? Or does Spring 4 WebSocket only supports Stomp?

Spring supports STOMP over WebSocket but the use of a subprotocol is not mandatory, you can deal with the raw websocket. When using a raw websocket, the message sent lacks of information to make Spring route it to a specific message handler method (we don't have any messaging protocol), so instead of annotating your controller, you'll have to implement a WebSocketHandler:
public class GreetingHandler extends TextWebSocketHandler {
#Override
public void handleTextMessage(WebSocketSession session, TextMessage message) {
Thread.sleep(3000); // simulated delay
TextMessage msg = new TextMessage("Hello, " + message.getPayload() + "!");
session.sendMessage(msg);
}
}
And then add your handler to the registry in the configuration (you can add more than one handler and use SockJS for fallback options):
#Configuration
#EnableWebSocket
public class WebSocketConfig implements WebSocketConfigurer {
#Override
public void registerWebSocketHandlers(WebSocketHandlerRegistry registry) {
registry.addHandler(greetingHandler(), "/greeting").withSockJS();
}
#Bean
public WebSocketHandler greetingHandler() {
return new GreetingHandler();
}
}
The client side will be something like this:
var sock = new SockJS('http://localhost:8080/greeting');
sock.onmessage = function(e) {
console.log('message', e.data);
}