How to mix spring-data-rest with spring websocket into a single implementation

[admin]

I'd like to synchronize the state to all the clients interested in particular entity changes. So I'd like to achieve something like:

<ul>
<li>exposing CRUD API on entity (via

HTTP/REST

and

websockets

)</li>
<li>and routing the response (of the modifying calls) to

websockets

topic</li>
</ul>

So technically, I'd be interested in ideas to mix <a href="http://projects.spring.io/spring-data-rest/">spring-data-rest</a> with <a href="https://raymondhlee.wordpress.com/2...mplement-two-way-server-client-communication/">spring websockets implementation</a> to achieve something like spring-data-websocket.

There are a two solutions coming to my mind, and in fact both would be:

<ul>
<li>spring-data-rest to expose my entities via

REST/HTTP API

</li>
<li>

websocket

controllers (used for the modification calls on entities) </li>
</ul>

The

websocket

controllers would look like this:

@Controller
public class EntityAWebSocketController {
      @MessageMapping("/EntityA/update")
      @SendTo("/topic/EntityA/update")
      public EntityA update(EntityA entityA) throws Exception {
           // persist,....
           return entityA;
     }
}

<strong>Scenario 1:

Websocket API

called from

REST/HTTP API

</strong>

Rules:

<ul>
<li>client request is always

REST/HTTP API

</li>
<li>response is

REST/HTTP API

for all the operations</li>
<li>moreover for modifying operations the

websocket

message comes as well</li>
</ul>

Technically, could be achieved, by:

<ul>
<li>calling the

websocket

controllers from the <a href="http://docs.spring.io/spring-data/rest/docs/2.0.0.M1/reference/html/events-chapter.html">spring-rest-data events</a> (namely in the

AfterCreateEvent

,

AfterSaveEvent

,

AfterLinkSaveEvent

,

AfterDeleteEvent

)</li>
</ul>

Still <strong>the solution seems quite sick to me</strong>, as I'd need to go for:

<ol>
<li>client A --

HTTP

request--> Server (spring-data-rest controller)</li>
<li>Server (AfterXXXEvent in the spring-data-rest controller) --

websocket

message--> Spring

websocket

controller</li>
<li>Spring websocket controller --

websocket

message via topic--> all Clients interested in the topic</li>
<li>Server (spring-data-rest controller) --

HTTP

response--> client A</li>
</ol>

<strong>Scenario 2:

Websocket API

independent from

REST API

</strong>

Rules:

<ul>
<li>client request is

REST/HTTP API

for non-modifying operations only</li>
<li>response is

REST/HTTP API

for non-modifying operations only</li>
<li>client sends

websocket

message for all the modifying operations</li>
<li>

websocket

message is sent to client for all the modifying operations only</li>
</ul>

Well, if no other ideas come up, I'd go for the later one, but still, it would be great if I could have somehow generated

C(R)UD

methods exposed via

websockets

as well, something like spring-data-websockets and handle only the routes in my implementation.

As I feel like I'd have to manually expose (via

*WebSocketController

s) all the

CUD

methods for all my entities. And I might be too lazy for that.

Ideas?