ai.grakn.engine.tasks.manager.singlequeue

Class TaskFailover

java.lang.Object

ai.grakn.engine.tasks.manager.singlequeue.TaskFailover

All Implemented Interfaces:

AutoCloseable, org.apache.curator.framework.recipes.cache.TreeCacheListener

public class TaskFailover
extends Object
implements org.apache.curator.framework.recipes.cache.TreeCacheListener, AutoCloseable

Re-schedule tasks that were running when an instance of Engine failed

Author:

Denis lobanov

Constructor Summary

Constructors

Constructor and Description
TaskFailover(org.apache.curator.framework.CuratorFramework client, TaskStateStorage stateStorage, org.apache.kafka.clients.producer.Producer<TaskId,TaskState> producer)

Method Summary

Modifier and Type	Method and Description
void	await() Block until this instance of TaskFailover fails with an unhandled error.
void	childEvent(org.apache.curator.framework.CuratorFramework client, org.apache.curator.framework.recipes.cache.TreeCacheEvent event) We want to requeue anything that is not on one of the currently running engines
void	close()
boolean	isAlive() The TaskRunners should only start/add themselves once a failover is alive

Methods inherited from class java.lang.Object

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

Constructor Detail

TaskFailover

public TaskFailover(org.apache.curator.framework.CuratorFramework client,
                    TaskStateStorage stateStorage,
                    org.apache.kafka.clients.producer.Producer<TaskId,TaskState> producer)
             throws Exception

Throws:

Exception

Method Detail

close

public void close()

Specified by:

close in interface AutoCloseable

isAlive

public boolean isAlive()

The TaskRunners should only start/add themselves once a failover is alive

await

public void await()

Block until this instance of TaskFailover fails with an unhandled error.

childEvent

public void childEvent(org.apache.curator.framework.CuratorFramework client,
                       org.apache.curator.framework.recipes.cache.TreeCacheEvent event)
                throws Exception

We want to requeue anything that is not on one of the currently running engines

Specified by:

childEvent in interface org.apache.curator.framework.recipes.cache.TreeCacheListener

Throws:

Exception