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Best way to use Websocket with Spring Boot and Vuejs

I try to use Websocket with spring boot backend (as an API) and Vuejs frontend.
I take a simple use case to expose my question. Some users are logged on my website, and there is a messaging feature. User A send a message to User B. User B is actually logged, and I want to notify User B that a new message is arrived.
I see 3 ways to do it with websockets :
1 - When User A send message, an Axios post is call to the API for saving message, and, if the Axios response is success, I call something like
this.stompClient.send("/app/foo", JSON.stringify(bar), {})
2 - When User A send message, I only call something like
this.stompClient.send("/app/foo", JSON.stringify(bar), {})
and it's my controller's method (annotated with #MessageMapping("/xxxx") #SendTo("/topic/yyyy")) that call facade, service, dao to first, save message, then return message to subscribers
3 - I keep my actuals controllers, facade, services and DAO, and juste add when save is successfull something like :
#Autowired SimpMessagingTemplate webSocket;
...
#GetMapping("/send-message")
public ResponseEntity sendMessage(#AuthenticationPrincipal User user, ....) {
service.saveMessage(....);
webSocket.convertAndSend("/ws/message-from", message);
without a new controller contains #MessageMapping("/xxxx") #SendTo("/topic/yyyy"). User B is just subscibed to "/ws/message-from"
Could you help me.
In the 3 way there is a good method ?
Thanks you.

The one and two method has no much difference as you use axios from npm for sending request and the other one you can directly,while the third one you use controller,and facade dao at single place.it is about architecture and how you wanna send your requests for your framework,as a requirement.
They serve best at their level,till you come with specific requirement.
The suggestion would be to use axios.
It has advantages:
supports older browsers (Fetch needs a polyfill)
has a way to abort a request
has a way to set a response timeout
has built-in CSRF protection
supports upload progress
performs automatic JSON data transformation
works in Node.js

Spring boot - Threads / Feign-Client / Messaging / Streamlistener

We struggle to find a solution for the following scenario:
Situation
Receive a message via Spring Cloud Streamlistener
Invoke a REST-Service via Feign-Client
We have configured several Feign-RequestInterceptor to enrich
request header data.
We want to avoid passing every request header on the method call and like the central configuration approach of the request interceptors.
Problem:
How to access data from a specific message, which contains informations, that need to be added to every request call via the Feign-RequestInterceptor.
We don't have a Request-Context, as we come from a message.
Can we be sure , that the message consumption and the REST call is happening on the same thread? If yes, we could use the NamedThreadLocal to store the information.

Yes, unless you hand off to another thread in your StreamListener, the rest call will be made on the same thread (assuming you are using RestTemplate and not the reactive web client).

How do I ensure my Java Play application only accepts HTTP requests from a particular host?

I'm using the Play framework for Java for an app. I am attempting to make it distributed by deploying copies of the application across several servers and having a configurable list of nodes in the database, which must be able to communicate between each other. In MongoDB, the list is stored in JSON like so:
{
"master": "host1.com:2678",
"nodes": ["host2.com:2678", "host3.com:2678", "host4.com:2678"]
}
The code deployed on each server is identical, but the scheduler is enabled only on the master node and will schedule particular work to nodes depending on how busy they are. Code not provided here as the specifics of the scheduler's operation isn't important for my question.
In order to know how busy they are, to schedule things and for other status updates, the nodes need to be able to communicate with each other.
Play Framework's Web Service client allows me to do this by making HTTP requests from within one node to the other like so
HttpResponse res = WS.url("http://host2.com").get();
But the idea is for specific HTTP requests (such as those used for scheduling) to be allowed only if coming from another one of the nodes (Be it the master or slave nodes) but not from a web browser, curl, etc. How do I do that securely? I can check for the host of the incoming request or particular headers but surely those are easy to forge?

If you want this to be enforced on all controllers, Check out play allowed hosts filter.
If you want to enforce this filter on a specific Controller \ method you can try to do this:
class MyController #Injects()(filter: AllowedHostsFilter) extends Controller {
def get = filter.apply(Action.async { implicit request =>
Future.successful(Ok)
})
}

You could have a look into pac4j.org they have a lot of options to implement security features on play.
You could maybe filter by ip address:
http://www.pac4j.org/1.9.x/docs/authenticators/ip.html

How to create a listener/Tracer for my web services

I have around 20 APIs up and running in my domain.
I need to create a listener in java for tracing all my request and response patterns including headers and store it in a DB.
If u have any suggestions or idea, please refer to me the same.

Use a Servlet Filter to map to generic URL pattern of your APIs. You can dump request and response headers in the doFilter method.
For your reading : http://www.oracle.com/technetwork/java/filters-137243.html

Passing object from Spring HandlerInterceptor to Servlet Filter

There is a webapp, where every request consumes various external resources. The webapp tracks those consumed resources with request scooped bean. Then HandlerInterceptor's afterCompletion method calls TaskExecutor to store this information in DB. All is fine and dandy, but there goes the requirement to add bandwith consumption as another resource. Counting outgoing response size is a typical task for servlet filter (along with response wrapper and custom stream implementation). So this is done and is also working.
The problem is that I'd like to aggregate two things together. Obviously, I can't pass "bytes sent" to Spring HandlerInterceptor, because filter's doFilter() hasn't completed yet and the amount of bytes sent isn't known when the interceptor runs. So filter must be the place to aggregate all the resource usage and start async task to store it in DB. The problem is: how can I pass data from HandlerInterceptor to Filter. I've tried simple request.setAttribute() but surprisingly it didn't worked.
As a side note: I'm aware of request scooped bean lifecycle and at the handler I'm creating a simple POJO populated with data from scooped bean.

The problem turned out to be quite trival. The app was doing a lot of forward/dispatches as a part of somehwat normal request handling. It turned out that the my filter was called (so far, so good) then another filter down the chain was doing forward/dispatch which then did actual request processing. Default filter setup catches only plain requests and you need additional configuration (web.xml) to also filter forwards/dispatches. I just did that and that solved the problem.