How to Convert callback to a Promise

Question

I am using play framework and Apache Kafka.

I have a POST method which sends a message to Kafka. Kafka has an API method

public java.util.concurrent.Future send

Answer 1

After some searching found the answer with some help from this one.

Following is the code

RedeemablePromise<Result> promise = RedeemablePromise.empty();

kafkaProducer.send(record, (metadata, ex) -> {
    if (ex != null) {
        promise.failure(ex);
    } else {
        promise.success(created(Json.toJson(new ProduceResult())));
    }
});