org.apache.sling.hc.api

Interface HealthCheck

public interface HealthCheck

Health Check services can be executed and return an execution Result. Clients should not look up health checks directly but rather use the HealthCheckExecutor service and executed checks based on tags. If the MBEAN_NAME service registration property is set, the health check is registered as an mbean and can be invoked by getting the MBean from the JMX registry.

Field Summary

Fields

Modifier and Type	Field and Description
static java.lang.String	ASYNC_CRON_EXPRESSION Optional service property: If this property is set the health check will be executed asynchronously using the cron expression provided.
static java.lang.String	MBEAN_NAME Optional service property: the name of the MBean for registering the health check as an MBean.
static java.lang.String	NAME Optional service property: the name of a health check.
static java.lang.String	RESULT_CACHE_TTL_IN_MS Optional service property: TTL for health check Result.
static java.lang.String	TAGS Optional service property: tags for categorizing the health check services.
static java.lang.String	WARNINGS_STICK_FOR_MINUTES Optional service property: If given, warning results (that is WARN, CRITICAL or HEALTH_CHECK_ERROR) from the past executions will be taken into account as well for the given minutes (use Integer.MAX_VALUE for indefinitely).

Method Summary

Modifier and Type	Method and Description
Result	execute() Execute this health check and return a Result This is meant to execute quickly, access to external systems, for example, should be managed asynchronously.

Field Detail

NAME

static final java.lang.String NAME

Optional service property: the name of a health check. This name should be unique, however there might be more than one health check service with the same value for this property. The value of this property must be of type String.

See Also:

Constant Field Values

MBEAN_NAME

static final java.lang.String MBEAN_NAME

Optional service property: the name of the MBean for registering the health check as an MBean. If this property is missing the health check is not registered as a JMX MBean. If there is more than one service with the same value for this property, the one with the highest service ranking is registered only. The value of this property must be of type String.

See Also:

Constant Field Values

TAGS

static final java.lang.String TAGS

Optional service property: tags for categorizing the health check services. The value of this property must be of type String or String array.

See Also:

Constant Field Values

ASYNC_CRON_EXPRESSION

static final java.lang.String ASYNC_CRON_EXPRESSION

Optional service property: If this property is set the health check will be executed asynchronously using the cron expression provided.

See Also:

Constant Field Values

RESULT_CACHE_TTL_IN_MS

static final java.lang.String RESULT_CACHE_TTL_IN_MS

Optional service property: TTL for health check Result. The value of this property must be of type Long and is specified in ms.

See Also:

Constant Field Values

WARNINGS_STICK_FOR_MINUTES

static final java.lang.String WARNINGS_STICK_FOR_MINUTES

Optional service property: If given, warning results (that is WARN, CRITICAL or HEALTH_CHECK_ERROR) from the past executions will be taken into account as well for the given minutes (use Integer.MAX_VALUE for indefinitely). Useful for unhealthy system states that disappear but might leave the system at an inconsistent state (e.g. an event queue overflow).

See Also:

Constant Field Values

Method Detail

execute

Result execute()

Execute this health check and return a Result This is meant to execute quickly, access to external systems, for example, should be managed asynchronously.