I am facing a problem with vert.x. When the timeout is triggered it generates a response, then the actual response (takes 10 sec) comes and tries to do the response, so I get a:
java.lang.IllegalStateException: Response has already been written
I am new with Vert.x and I am not sure about the desired behaviour, How should I do it?, since the code is asynchronous I don't find the way to check whether the response has been already sent.
Is there any way to do it porperly?
I have this code:
private void setExternalCallAccessibleWithCircuitBreaker() {
CircuitBreaker breaker = CircuitBreaker.create("my-circuit-breaker", vertx,
new CircuitBreakerOptions().setMaxFailures(3) // number of failure before opening the circuit
.setTimeout(1000) // consider a failure if the operation does not succeed in time
.setFallbackOnFailure(true) // do we call the fallback on failure
.setResetTimeout(10000) // time spent in open state before attempting to re-try
);
vertx.createHttpServer().requestHandler(req -> {
// some code executing with the breaker
// the code reports failures or success on the given future.
// if this future is marked as failed, the breaker increased the
// number of failures
breaker.executeWithFallback(future -> {
// call the external service
WebClient client = WebClient.create(vertx);
client.get(8080, "localhost", "/wait10Seconds").send(ar -> {
if (ar.succeeded()) {
HttpResponse<Buffer> response = ar.result();
System.out.println("Received response with status code" + response.statusCode());
System.out.println("response.bodyAsString()" + response.bodyAsString());
req.response().end(response.body());
future.complete();
} else {
System.out.println("Something went wrong " + ar.cause().getMessage());
req.response().end("error");
future.fail("not possible to complete the request");
}
});
}, (Throwable exception) -> {
req.response().end("error " + exception.getMessage());
return exception;
}).setHandler(ar -> {
// Get the operation result.
System.out.println("ar: " + ar);
});
}).listen(8088);
System.out.println("Running");
}
I found out this method, apparently it works:
if (!req.response().ended()) {
req.response().end(response.body());
}