Spring - Sock.js - websockets: blocked by CORS policy

Question

I am implementing websockets to Spring App with sock.js + stomp.js on the client app. When trying to connect I am getting the error:

Access to XMLHttpRequest at 'http://localhost:8080/ws/tracker/info?t=...' from origin 'null' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.

And in my WebsocketConfiguration :

@Configuration
@EnableWebSocketMessageBroker
@Order(Ordered.HIGHEST_PRECEDENCE + 99)
public class WebsocketConfiguration implements WebSocketMessageBrokerConfigurer {

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

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

Client libraries:

<script src="https://cdnjs.cloudflare.com/ajax/libs/sockjs-client/1.4.0/sockjs.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/stomp.js/2.3.3/stomp.js"></script>

Client connection:

var socket = new SockJS('http://localhost:8080/websocket/tracker');

I have already implemented websockets in one of the earlier projects, so this is all copied from it, though I can't remember (nor find) how to solve this error.

Answer 1

Check if you have ClientForwardController, mapping should be like this:

@GetMapping(value = {"/{path:[^\\.]*}", "/{path:^(?!websocket).*}/**/{path:[^\\.]*}"})
public String forward() {
    return "forward:/";
}