Skip to main content
Version: v11.*.*

HealthCheck

KadaiAdapter also provides a way to monitor its health - built on top of SpringBoot Actuator.

Assuming that the adapter application runs at http://localhost:8082 you can request below URL for all health-information:

GET http://localhost:8082/actuator/health

Kernel​

The hierarchical nature allows to just request health information for specific sub-systems, e.g. all kernel-components:

GET http://localhost:8082/actuator/health/kadaiAdapter/kernel
{
  "status": "UP",
  "components": {
    "kadai": {
      "status": "UP",
      "details": {
        "kadaiVersion": "11.0.1-SNAPSHOT"
      }
    },
    "scheduler": {
      "status": "UP",
      "components": {
        "kadaiTaskStarter": {
          "status": "UP",
          "details": {
            "lastRun": "2025-10-07T10:39:18.036280700Z",
            "expectedNextRunBefore": "2025-10-07T10:39:38.185300900Z",
            "expectedRunTime": 149
          }
        },
        "kadaiTaskTerminator": {
          "status": "UP",
          "details": {
            "lastRun": "2025-10-07T10:39:18.045281300Z",
            "expectedNextRunBefore": "2025-10-07T10:39:38.064082400Z",
            "expectedRunTime": 18
          }
        },
        "referencedTaskClaimCanceler": {
          "status": "UP",
          "details": {
            "lastRun": "2025-10-07T10:39:18.065285700Z",
            "expectedNextRunBefore": "2025-10-07T10:39:38.103276500Z",
            "expectedRunTime": 37
          }
        },
        "referencedTaskClaimer": {
          "status": "UP",
          "details": {
            "lastRun": "2025-10-07T10:39:18.065285700Z",
            "expectedNextRunBefore": "2025-10-07T10:39:38.103276500Z",
            "expectedRunTime": 37
          }
        },
        "referencedTaskCompleter": {
          "status": "UP",
          "details": {
            "lastRun": "2025-10-07T10:39:18.065285700Z",
            "expectedNextRunBefore": "2025-10-07T10:39:38.103276500Z",
            "expectedRunTime": 37
          }
        }
      }
    }
  }
}

Kadai​

When healthy, it should return the KADAI version being used

  • kadaiVersion specifies the current running version of KADAI

Scheduler​

Health-Composite, healthy if all Health-Contributors are healthy.

Each Health-Contributor provides the following information:

  • lastRun: The last successfully reported run
  • expectedNextRunBefore: The latest point in time the next scheduled run is expected to have been reported successful
  • expectedRunTime: The expected run-time in milliseconds for a single run of the scheduled functionality, reported as lower median

If any of the services is not running properly, the overall status will be DOWN and the error will be shown in the "details".

The expectedNextRunBefore can be configured by supplying an acceptance-multiplier for threshold. It determines expectedNextRunBefore = run-time-acceptance-multiplier * expectedRunTime + lastRun. It can be set via:

application.properties
management.health.kadai-adapter.kernel.scheduler.run-time-acceptance-multiplier=42

Plugins​

Camunda 7​

The URLs for the Camunda7-Systems are derived from the property kadai-system-connector-camundaSystemURLs.

Example-Response​

http://localhost:8082/actuator/health/kadaiAdapter/plugin/camunda7
{
  "status": "UP",
  "components": {
    "camundaSystem1": {
      "status": "UP",
      "components": {
        "camunda": {
          "status": "UP",
          "details": {
            "camundaEngines": [
              {
                "name": "default"
              }
            ],
            "baseUrl": "http://localhost:8081/example-context-root/engine-rest/engine"
          }
        },
        "outbox": {
          "status": "UP",
          "details": {
            "outboxService": {
              "eventsCount": 0
            },
            "baseUrl": "http://localhost:8081/example-context-root/outbox-rest"
          }
        }
      }
    }
  }
}

Camunda Systems​

  • camunda7 contains a composite of Camunda7-Systems

Camunda System​

  • camundaSystem[i] contains the health of the i-th Camunda- and Outbox-Component

Camunda​

When healthy, it should return a list of the available Camunda Engines

  • camundaEngines lists the available Camunda engines by name.
  • baseUrl shows the base URL for the Camunda REST

Outbox​

When healthy, it should return the count of events in the outbox

  • outboxService.eventsCount represents the number of unprocessed events in the outbox
  • baseUrl shows the base URL for the Outbox REST

Camunda 8​

Unlike Camunda7 we do not include the health of the Camunda8-instance itself in here. You can inspect that separately with the Health-Endpoints provided by Camunda, see Orchestration-Cluster/Zeebee/Health.

Example-Response​

http://localhost:8082/actuator/health/kadaiAdapter/plugin/camunda8
{
  "status": "UP",
  "components": {
    "jobWorker": {
      "status": "UP",
      "components": {
        "complete": {
          "status": "UNKNOWN",
          "details": {
            "lastRun": null,
            "expectedRunTime": 0
          }
        },
        "create": {
          "status": "UP",
          "details": {
            "lastRun": "2025-10-16T08:55:19.287769500Z",
            "expectedRunTime": 55
          }
        },
        "cancel": {
          "status": "UP",
          "details": {
            "lastRun": "2025-10-16T08:55:20.474158400Z",
            "expectedRunTime": 74
          }
        }
      }
    }
  }
}

Job-Worker​

The health-composite of all job-workers.

Create (Job-Worker)​

The health-indicator for the job-worker responsible for reacting to user-tasks being created.

Complete (Job-Worker)​

The health-indicator for the job-worker responsible for reacting to user-tasks being completed.

Cancel (Job-Worker)​

The health-indicator for the job-worker responsible for reacting to user-tasks being cancelled.

Register a Health-Indicator for your own plugin​

The starting-point for registering health-indicators for your own plugins is interface PluginHealthContributorFactory.

io.kadai.adapter.monitoring.PluginHealthContributorFactory
/**
 * Instantiated factory for KadaiAdapter-specific plugin-health-contributors.
 *
 * <p>Implement this interface for any contributing Health-Indicators.
 *
 * <p>Implementations of this interface will be picked up by {@link KadaiAdapterHealth} via
 * <b>classpath-scanning</b> in a SpringBoot-Application. Therefore, you <b>need to</b> lift your
 * implementation into the Spring-Context, e.g. by annotating it as {@code @Component}.
 */
public interface PluginHealthContributorFactory {

  /**
   * Returns the name of the plugin.
   *
   * <p>This name will be used as an <b>identifier</b> for Health-Contributors created by
   * <i>this</i> factory. It will further be used as JSON-Field in the actuators' health-response.
   *
   * @return name of the plugin
   */
  String getPluginName();

  /**
   * Returns an optional instance of the Health-Contributor created by <i>this factory</i>.
   *
   * <p>It may return {@link Optional#empty()}, e.g. to control activation of this plugin through
   * extra properties.
   *
   * @return an optional instance of the Health-Contributor
   */
  Optional<HealthContributor> newInstance();
}

Implement it and make sure your implementing class can be picked-up by Spring, e.g. by annotating it with @Component. That's it! The KadaiAdapter will now automatically pick up your implementation and expose it via actuator. It may then look like this:

my.org.kadai.adapter.plugin.monitoring.MyPluginHealthContributorFactory

@Component
public class MyPluginHealthContributorFactory implements PluginHealthContributorFactory {

  @Override
  public String getPluginName() {
    return "my-plugin";
  }

  @Override
  public Optional<HealthContributor> newInstance() {
    final MyHealthContributor myHealthContributor = new MyHealthContributor();
    return Optional.of(myHealthContributor); // HealthComposite or -Indicator - whatever you wish!
  }
}

Partially disabling Health-Indicators​

By default, all kernel- as well as all found plugin-health-composites and -indicators are enabled.

The KadaiAdapter-Health is a Rose-Tree where the root is kadaiAdapter - the composite of all Health-indicators related to the KadaiAdapter. Branches are Health-Composites - themselves composed of Health-Trees. Leafs are Health-Indicators. In this tree you can

  • fully disable any branch branch (composite) and it's children by setting management.health.kadai-adapter.branch.enabled=false, e.g.:
    • management.health.kadai-adapter.kernel.enabled=false
    • management.health.kadai-adapter.plugin.enabled=false
    • management.health.kadai-adapter.plugin.camunda7.enabled=false
  • partially disable any of a composites contributors contributor by setting management.health.kadai-adapter.branch.contributor.enabled=false, e.g.:
    • management.health.kadai-adapter.kernel.kadai.enabled=false
    • management.health.kadai-adapter.kernel.kadai.scheduler=false
    • management.health.kadai-adapter.plugin.camunda7.outbox.enabled=false
    • management.health.kadai-adapter.kernel.scheduler.kadai-task-terminator.enabled=false

This schema applies to all parts of the KadaiAdapter-HealthCheck.