0

I am using Play! 2.5 (Java) and Akka. Here's my problem: I am trying to call an external service using WSClient and would like it to be behind a Akka circuit breaker. The code I have shown below doesn't seem to work as expected.

I would expect the circuit breaker to open when the external service is not reachable, but it doesn't. I am guessing the problem is in wrapping a java 8 lambda expression returning a completableFuture inside a akaa.dispatch.Future.future .

Does the code I have look correct? If there is something wrong how can i fix it?

    @Inject
    public ServiceActor(WSClient ws) {

        this.ws = ws;

        circuitBreaker = new CircuitBreaker(getContext().dispatcher(),
                getContext().system().scheduler(),
                MAX_FAILURES,
                CALL_TIMEOUT,
                RESET_TIMEOUT
        )
.onOpen(this::onOpen)
.onClose(this::onClose)
.onHalfOpen(this::onHalfOpen);

        receive(ReceiveBuilder
                .match(String.class, x -> {
                            circuitBreaker.callWithCircuitBreaker(() -> future(() -> callService(),getContext().dispatcher()));
                })
                .matchAny(o -> log.info("Unknown message"))
                .build()
        );
    }

private CompletableFuture<JsonNode> callService() {
        return  ws.url(SOME_URL).get()
                .thenApply(WSResponse::asJson)
                .toCompletableFuture();
}

If i simply throw a runtime expression in callService without doing anything like:

   private CompletableFuture<JsonNode> callService() {
           throw new RuntimeException()
    }

Now, the circuit-breaker opens.

jesukumar
  • 1,139
  • 9
  • 19

1 Answers1

2

I figured out how to get it to work. Using callWithCircuitBreakerCS returns a Java 8 completion stage which is what I want, using that fixed my problem and the exceptions result in setting the circuitbreaker to a open state.

jesukumar
  • 1,139
  • 9
  • 19