Kafka High Level Consumer Fetch All Messages From Topic Using Java API (Equivalent to --from-beginning)

Question

I am testing the Kafka High Level Consumer using the ConsumerGroupExample code from the Kafka site. I would like to retrieve all the existing messages on the topic called "test" that I have in the Kafka server config. Looking at other blogs, auto.offset.reset should be set to "smallest" to be able to get all messages:

private static ConsumerConfig createConsumerConfig(String a_zookeeper, String a_groupId)    {
    Properties props = new Properties();
    props.put("zookeeper.connect", a_zookeeper);
    props.put("group.id", a_groupId);
    props.put("auto.offset.reset", "smallest");
    props.put("zookeeper.session.timeout.ms", "10000");     

    return new ConsumerConfig(props);
}

The question I really have is this: what is the equivalent Java api call for the High Level Consumer that is the equivalent of:

bin/kafka-console-consumer.sh --zookeeper localhost:2181 --topic test --from-beginning

Answer 1

Basically, everytime a new consumer tries to consume a topic, it'll read messages from the beginning. If you're especially just consuming from the beginning each time for testing purposes, everytime you initialise your consumer with a new groupID, it'll read the messages from the beginning. Here's how I did it :

properties.put("group.id", UUID.randomUUID().toString());

and read messages from the beginning each time!