Accepting/Rejecting a WebSocket asynchronously

[Isaac Pereira]

In my application, in play 2.6.x (java), I have a websocket endpoint, but I need to do some async db operation before accept/reject it. Like this:

public CompletionStage<WebSocket> subscribe(String username) {

 return userRepo.getUserByUsername(username).thenApplyAsync(
    userOpt -> {
      ...
             return WebSocket.Json.accept(
                 request -> ActorFlow.actorRef(...)
             );
      ...
    },
    ...
 )

But I get this when starting the application:

play.sbt.PlayExceptions$CompilationException: Compilation error[Cannot use a method returning java.util.concurrent.CompletionStage[play.mvc.WebSocket] as a Handler for requests]

Am I getting it wrong? https://www.playframework.com/documentation/2.6.x/JavaWebSockets#accepting-a-websocket-asynchronously

How could I achieve that?

Best Regards

[vahid islami]

I have same problem! did you resolve that?