ai.grakn.engine.backgroundtasks.distributed

Class DistributedTaskManager

java.lang.Object

ai.grakn.engine.backgroundtasks.distributed.DistributedTaskManager

All Implemented Interfaces:

TaskManager, AutoCloseable

public final class DistributedTaskManager
extends Object
implements TaskManager

Class to manage tasks distributed using Kafka.

Author:

Denis Lobanov This class begins the TaskRunner instance that will be running on this machine.

Constructor Summary

Constructors

Constructor and Description
DistributedTaskManager()

Method Summary

Modifier and Type	Method and Description
void	close()
String	createTask(String taskClassName, String createdBy, java.time.Instant runAt, long period, mjson.Json configuration) Schedule a single shot/one off BackgroundTask to run after a @delay in milliseconds.
TaskManager	stopTask(String id, String requesterName) Stop a Scheduled, Paused or Running task.
TaskStateStorage	storage() Return the StateStorage instance that is used by this class.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

DistributedTaskManager

public DistributedTaskManager()

Method Detail

close

public void close()

Specified by:

close in interface AutoCloseable

createTask

public String createTask(String taskClassName,
                         String createdBy,
                         java.time.Instant runAt,
                         long period,
                         mjson.Json configuration)

Description copied from interface: TaskManager

Schedule a single shot/one off BackgroundTask to run after a @delay in milliseconds. All parameters must not be null unless stated otherwise.

Specified by:

createTask in interface TaskManager

Parameters:

taskClassName - Name of the class implementing the BackgroundTask interface that is to be scheduled for later execution.

runAt - Instant when task should run.

period - A non-zero value indicates that this should be a recurring task and period indicates the delay between subsequent runs of the task after successful execution.

configuration - A JSONObject instance containing configuration and optionally data for the task. This is an optional parameter and may be set to null to not pass any configuration (task.start() will get an initialised but empty JSONObject).

Returns:

Assigned ID of task scheduled for later execution.

stopTask

public TaskManager stopTask(String id,
                            String requesterName)

Description copied from interface: TaskManager

Stop a Scheduled, Paused or Running task. Task's .stop() method will be called to perform any cleanup and the task is killed afterwards.

Specified by:

stopTask in interface TaskManager

Parameters:

id - String of task to stop.

requesterName - Optional String to denote who requested this call; used for status reporting and may be null.

Returns:

Instance of the class implementing TaskManager.

storage

public TaskStateStorage storage()

Description copied from interface: TaskManager

Return the StateStorage instance that is used by this class.

Specified by:

storage in interface TaskManager

Returns:

A StateStorage instance.