How to extend existing actuator health check endpoint?

Question

There are existing actuator health endpoints, such as:

/actuator/health

How would I extend this existing endpoint to say:

/actuator/health/myendpoint

in order to perform some health check?

Current code:

package com.example.actuatordemo.health;

import org.springframework.boot.actuate.health.AbstractHealthIndicator;
import org.springframework.boot.actuate.health.Health;
import org.springframework.stereotype.Component;

@Component
public class CustomHealthIndicator extends AbstractHealthIndicator {

    @Override
    protected void doHealthCheck(Health.Builder builder) throws Exception {
        // Use the builder to build the health status details that should be reported.
        // If you throw an exception, the status will be DOWN with the exception message.

        builder.up()
                .withDetail("app", "Testing endpoint extension!")
                .withDetail("error", "Oops.");
    }
}

Answer 1

In order to extend the /health endpoint, you have to implement the HealthIndicator interface like so. In this example, the customized HealthService returns a map of the desired values you want to add to the health endpoint.

  import com.metavera.tako.fc.service.HealthService;
  import org.springframework.beans.factory.annotation.Autowired;
  import org.springframework.boot.actuate.health.*;
  import org.springframework.stereotype.Component;

  import java.util.Map;


  @Component
  public class HealthCheck implements HealthIndicator {

  @Autowired
  HealthService healthService;


  @Override
  public Health health() {
      return myCustomHealth();
  }

  private Health myCustomHealth() {
      Health.Builder builder = new Health.Builder(Status.UP);
      Map<String, Object> response = healthService.getHealthStatus();

      for (Map.Entry<String, Object> entry : response.entrySet()) {
          String key = entry.getKey();
          Object value = response.get(key);
          builder.withDetail(key, value);
      }
      return builder.build();
  }
}

While the above solution allows you to modify the existing /health endpoint, there is additional documentation on how to create custom endpoints here under section 53.7.

https://docs.spring.io/spring-boot/docs/current/reference/html/production-ready-endpoints.html

Although this is not limited to just health check operations.