mbode / kafka-junit

JUnit rule for spinning up a Kafka broker

Kafka JUnit Rule

JUnit rule for starting and tearing down a Kafka broker during tests.

Please note that version 3.x.x drops Java 7 support and contains breaking API changes.

Version	Kafka Version
1.6	0.8.2.1
1.7	0.8.2.2
1.8	0.9.0.0
2.3	0.9.0.1
2.4	0.10.0.0
2.5	0.10.0.1
3.0.0	0.10.0.1
3.0.1	0.10.0.1
3.0.2	0.10.1.1
3.0.3	0.10.2.0

Installation

Releases are available on Maven Central.

Snapshot versions containing builds from the latest master are available in the Sonatype snapshots repo.

Javadocs

http://charithe.github.io/kafka-junit/

Usage

Create an instance of the rule in your test class and annotate it with @Rule. This will start and stop the broker between each test invocation.

@Rule
public KafkaJunitRule kafkaRule = new KafkaJunitRule(EphemeralKafkaBroker.create());

To spin up the broker at the beginning of a test suite and tear it down at the end, use @ClassRule.

@ClassRule
public static KafkaJunitRule kafkaRule = new KafkaJunitRule(EphemeralKafkaBroker.create());

kafkaRule can be referenced from within your test methods to obtain information about the Kafka broker.

@Test
public void testSomething(){
    // Convenience methods to produce and consume messages
    kafkaRule.helper().produceStrings("my-test-topic", "a", "b", "c", "d", "e");
    List<String> result = kafkaRule.helper().consumeStrings("my-test-topic", 5).get();

    // or use the built-in producers and consumers
    KafkaProducer<String, String> producer = kafkaRule.helper().createStringProducer();

    KafkaConsumer<String, String> consumer = kafkaRule.helper().createStringConsumer();

    // Alternatively, the Zookeeper connection String and the broker port can be retrieved to generate your own config
    String zkConnStr = kafkaRule.helper().zookeeperConnectionString();
    int brokerPort = kafkaRule.helper().kafkaPort();
}

EphemeralKafkaBroker contains the core logic used by the JUnit rule and can be used independently.

KafkaHelper contains a bunch of convenience methods to work with the EphemeralKafkaBroker

Refer to Javadocs and unit tests for more usage examples.