HttpSession in Spring's HttpSessionHandshakeInterceptor

I used Spring 4.3.5 with SpringBoot 1.4.3 with dependencies spring-boot-starter-webmvc, spring-boot-starter-tomcat and spring-boot-starter-websocket.

I configure the websocket handlr this way:

WebSocketHandler wsChannelReceiver = wsChannelReceiver();
registry.addHandler(wsChannelReceiver, "/ws").addInterceptors(new HttpSessionHandshakeInterceptor()).withSockJS()

WsChannelReceiver simply logs the session ID:

public class WsChannelReceiver extends TextWebSocketHandler
{
   @Override
   public void afterConnectionEstablished(WebSocketSession pSession) throws Exception
   {
      mLogger.info("Establish web socket connection with client session id = %s.", pSession.getId());
      mLogger.info("Establish web socket connection with client session attribute = %s.", pSession.getAttributes().get(HttpSessionHandshakeInterceptor.HTTP_SESSION_ID_ATTR_NAME));
      super.afterConnectionEstablished(pSession);
   }

I also log the session ID in a REST controller:

@RestController
public class Handler
{
   @PostMapping
   @RequestMapping("/greet")
   public String greeting(@RequestParam(value = "name", required = false, defaultValue = "World") String pName, HttpServletRequest pRequest, HttpServletResponse pResponse)
   {
      mLogger.info("Incoming greet request from client session id = %s.", pRequest.getSession().getId());
      return "Hello " + pName;
   }
}

In my client code, I call the REST method, then I conect the websocket. I get this output:

2017-10-11 11:50:30,314 [ INFO] {http-nio-8081-exec-2} (PmsHandler) - Incoming greet request from client session id = 90B5B7FF8F0F4EBB7D7C07416391B220.
2017-10-11 11:50:41,768 [ INFO] {http-nio-8081-exec-4} (WsChannelReceiver) - Establish web socket connection with client session id = 4nwjmjep.
2017-10-11 11:50:41,768 [ INFO] {http-nio-8081-exec-4} (WsChannelReceiver) - Establish web socket connection with client session attribute = null.

Inside HttpSessionHandshakeInterceptor, I can see that the call to HttpSession getSession(ServerHttpRequest request) actually returns null.

There is indeed a createSession option on HttpSessionHandshakeInterceptor, but in this case the session ID in the REST controller does not match the session ID in the WsChannelReceiver.

The goal is to be able to find the client's WebSocketSession from inside a REST handler. Is there a way to achieve this with Spring?

Thanks!