Examples with KafkaClientFactory org.eclipse.hono.client.kafka.KafkaClientFactory used on opensource projects

Example 1 with KafkaClientFactory

use of org.eclipse.hono.client.kafka.KafkaClientFactory in project hono by eclipse.

the class HonoKafkaConsumer method start.

@Override
public Future<Void> start() {
    context = vertx.getOrCreateContext();
    final Promise<Void> startPromise = Promise.promise();
    runOnContext(v -> {
        // create KafkaConsumer here so that it is created in the Vert.x context of the start() method (KafkaConsumer uses vertx.getOrCreateContext())
        Optional.ofNullable(kafkaConsumerSupplier).map(supplier -> Future.succeededFuture(KafkaConsumer.create(vertx, supplier.get()))).orElseGet(() -> {
            final KafkaClientFactory kafkaClientFactory = new KafkaClientFactory(vertx);
            return kafkaClientFactory.createKafkaConsumerWithRetries(consumerConfig, String.class, Buffer.class, consumerCreationRetriesTimeout);
        }).onFailure(thr -> {
            log.error("error creating consumer [client-id: {}]", getClientId(), thr);
            startPromise.fail(thr);
        }).onSuccess(consumer -> {
            kafkaConsumer = consumer;
            Optional.ofNullable(metricsSupport).ifPresent(ms -> ms.registerKafkaConsumer(kafkaConsumer.unwrap()));
            kafkaConsumer.handler(record -> {
                if (!startPromise.future().isComplete()) {
                    log.debug("postponing record handling until start() is completed [topic: {}, partition: {}, offset: {}]", record.topic(), record.partition(), record.offset());
                }
                startPromise.future().onSuccess(v2 -> {
                    if (respectTtl && KafkaRecordHelper.isTtlElapsed(record.headers())) {
                        onRecordHandlerSkippedForExpiredRecord(record);
                    } else {
                        try {
                            recordHandler.handle(record);
                        } catch (final Exception e) {
                            log.warn("error handling record [topic: {}, partition: {}, offset: {}, headers: {}]", record.topic(), record.partition(), record.offset(), record.headers(), e);
                        }
                    }
                });
            });
            kafkaConsumer.batchHandler(this::onBatchOfRecordsReceived);
            kafkaConsumer.exceptionHandler(error -> log.error("consumer error occurred [client-id: {}]", getClientId(), error));
            installRebalanceListeners();
            // subscribe and wait for rebalance to make sure that when start() completes,
            // the consumer is actually ready to receive records already
            // let polls finish quickly until start() is completed
            kafkaConsumer.asStream().pollTimeout(Duration.ofMillis(10));
            subscribeAndWaitForRebalance().onSuccess(v2 -> {
                kafkaConsumer.asStream().pollTimeout(pollTimeout);
                logSubscribedTopicsOnStartComplete();
            }).onComplete(startPromise);
        });
    });
    return startPromise.future();
}