Spring-Boot – Custom Actuator

Let say you need a specific actuator for your Spring-Boot backend. This small post show you how to extend the interface HealthIndicator to create your custom actuator.

First you’ll have implement the HealthIndicator interface:

public class CustomHealthIndicator implements HealthIndicator {

  // You can inject all the others HealthIndicators if your custom actuators need it for your processing
  private final List<HealthIndicator> healthIndicators;

  public CustomHealthIndicator(List<HealthIndicator> healthIndicators) {
    this.healthIndicators = healthIndicators;
  }

  @Override
  public Health health() {
    Map<String, ?> details = Map.of();
    ...
    return Health.up().withDetails(details).build();
  }
}

Now you will try to make your custom actuator load at the start of you application, here is the “auto-configuration” you can use.

@Configuration
public class CustomHealthIndicatorAutoConfiguration {

  @ConditionalOnProperty(prefix = "custom-actuator", name = "enable", havingValue = "true", matchIfMissing = false)
  @Bean("CustomHealthIndicator")
  public HealthIndicator getCustomHealth(@Autowired List<HealthIndicator> healthIndicators) {
    return new CustomHealthIndicator(healthIndicators);
  }
}