kafka-actuators

A Spring Boot info actuator that displays the health of the Kafka cluster, based on the number of currently running kafka broker nodes, and a configurable broker setting (by default min.insync.replicas is used). If you use Kafka transactions, then it would make sense to use transaction.state.log.replication.factor instead.

Based on code that used to be part of the Spring Boot project, but was removed. Currently, there is no available Spring Boot Kafka actuator.

Examples:

• The currently running Kafka brokers are enough for the cluster to operate properly.

{
    "kafka": {
        "status": "HEALTHY",
        "clusterId": "jefgM2tdT7OjvthaNQK_1Q",
        "brokerId": "0",
        "minNumberOfNodesRequired": 1,
        "nodes": 1
    }
}

• The currently running Kafka brokers are less than the required number for the cluster to operate properly.

{
    "kafka": {
        "status": "UNHEALTHY",
        "clusterId": "jefgM2tdT7OjvthaNQK_1Q",
        "brokerId": "0",
        "minNumberOfNodesRequired": 2,
        "nodes": 1
    }
}

• The actuator failed to connect to the Kafka cluster.

{
    "kafka": {
        "status": "DOWN"
    }
}

Usage

Spring KafkaAdmin is required

Option 1: Standard spring auto-configuration

KafkaAdmin is by default created from Spring org.springframework.boot.autoconfigure.kafka.EnableAutoConfiguration via spring properties.

spring:
  kafka:
    admin:
      client-id: admin-client-id
    bootstrap-servers: ${config.kafkaBootstrapAddress}

Option 2: Manual creation

@Slf4j
@Configuration
public class KafkaActuatorsConfiguration {
	
	@Autowired
	private KafkaProperties config;
	
	@Primary
	@Bean
	public KafkaAdmin kafkaAdmin() {  
	    return new KafkaAdmin(Map.of(AdminClientConfig.BOOTSTRAP_SERVERS_CONFIG, config.kafkaBootstrapAddress()));
	}

}

Configuration properties

Parameter	Description	Example	Default Value	Required
enabled	If the actuator is enabled or not	enabled: true	false	Required
responseTimeout	How long to wait for a reply from Kafka	responseTimeout: PT5S	100 ms	Optional
brokerConfigurationProperty	Kafka broker property to compare to number of currently running nodes, for determining if the cluster is healthy or not	brokerConfigurationProperty: min.insync.replicas	min.insync.replicas	Optional

management:
  info:
    kafka:
      enabled: true
      # format https://en.wikipedia.org/wiki/ISO_8601#Durations (P[n]Y[n]M[n]DT[n]H[n]M[n]S)
      responseTimeout: PT5S
      # by default min.insync.replicas is used
      brokerConfigurationProperty: min.insync.replicas

Add as a dependency to your project

From Maven Central as follows:

<dependency>
  <groupId>io.github.vspiliop.monitoring</groupId>
  <artifactId>kafka-actuators</artifactId>
  <version>0.0.5</version>
</dependency>