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I’m new to Kafka and trying to implement a simple producer, sending data to a topic. If the topic doesn’t exist, I want to handle the sutiation as an exception.
private Producer<UUID, Object> producer = createProducer();
private static Producer createProducer() {
Properties props = new Properties();
props.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG,
"mybootstrapserveraddress");
props.put(ProducerConfig.CLIENT_ID_CONFIG, "ADAPTER");
props.put(ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG,
UUIDSerializer.class);
props.put(ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG,
JsonSerializer.class);
props.put(ProducerConfig.REQUEST_TIMEOUT_MS_CONFIG,
1000);
props.put(ProducerConfig.RETRIES_CONFIG,
1);
props.put(ProducerConfig.RETRY_BACKOFF_MS_CONFIG,
1000);
return new KafkaProducer<>(props);
}
public void send(Event event, String topic){
try {
UUID key = UUID.randomUUID();
producer.send(new ProducerRecord<>(topic, key , event), (rm, ex) -> {
if (ex != null) {
log.warn("Error sending message with key {}n{}", new Object[]{key, ex.getMessage()});
} else {
log.info( "Partition for key-value {} is {}", new Object[]{key, rm.partition()});
}
});
} catch (Exception e) {
log.error("Failed to send message ",e);
} finally {
producer.flush();
}
}
However, if the topic doesn’t exist, the message continues to be polled. Timeouts and retries from ProducerConfig are ignored.
[kafka-producer-network-thread | ADAPTER] WARN org.apache.kafka.clients.NetworkClient - [Producer clientId=ADAPTER] Error while fetching metadata with correlation id 6 : {my-example-topic2=UNKNOWN_TOPIC_OR_PARTITION}
[kafka-producer-network-thread | ADAPTER] WARN org.apache.kafka.clients.NetworkClient - [Producer clientId=ADAPTER] Error while fetching metadata with correlation id 7 : {my-example-topic2=UNKNOWN_TOPIC_OR_PARTITION}
[kafka-producer-network-thread | ADAPTER] WARN org.apache.kafka.clients.NetworkClient - [Producer clientId=ADAPTER] Error while fetching metadata with correlation id 8 : {my-example-topic2=UNKNOWN_TOPIC_OR_PARTITION}
I do not want to check that the topic exist through AdminClient. Kafka document https://kafka.apache.org/documentation/#producerconfigs was of no help.
Is there a way to fix the issue?
Answer
When the topic doesn’t exist the retry for getting metadata should ends after 60 seconds by default raising a timeout exception at the end.
The producer config parameter related to that is max.block.ms (default 60000).
As far as I know, there is no way to have feedback earlier than reducing this timeout or using the AdminClient (which is something you don’t want to do).