Add partitions for Kafka topic dynamically using Spring Boot?-CodePudding

I was able to inspect particular topic for its partitions:

public  void addPartitionIfNotExists(int partitionId){
    Map<String, TopicDescription> games = kafkaAdmin.describeTopics("games");
    TopicDescription gamesTopicDescription = games.get("games");
    List<TopicPartitionInfo> partitionsInfo = gamesTopicDescription.partitions();
    boolean partitionIdExists = partitionsInfo.stream().anyMatch(partitionInfo -> partitionInfo.partition() == partitionId);
    if (!partitionIdExists){
        //missing part
    }
}

But I haven't been able to add new partition to a already existing topic during runtime. Don't know if that is even possible.

CodePudding user response：

See KafkaAdminOperations Javadocs for more info:

/**
 * Create topics if they don't exist or increase the number of partitions if needed.
 * @param topics the topics.
 */
void createOrModifyTopics(NewTopic... topics);

Not sure in your logic around partitionIdExists though, since the partition in the Kafka topic is just an index number. So, if there is partition 3, it doesn't mean that there is no partitions 1 or 2. Therefore a NewTopic API is just that simple as numPartitions. Nothing more.

Technically, what you are asking is just covered by that createOrModifyTopics() and that's it: you don't need to check for topics yourself.