java.lang.Object
- org.elasticsearch.persistent.PersistentTasksClusterService

All Implemented Interfaces:

Closeable, AutoCloseable, ClusterStateListener
```
public class PersistentTasksClusterService
extends Object
implements ClusterStateListener, Closeable
```
Component that runs only on the master node and is responsible for assigning running tasks to nodes

Field Summary

Fields
Modifier and Type Field Description

static Setting<TimeValue> CLUSTER_TASKS_ALLOCATION_RECHECK_INTERVAL_SETTING

Constructor Summary

Constructors
Constructor	Description
`PersistentTasksClusterService(Settings settings, PersistentTasksExecutorRegistry registry, ClusterService clusterService, ThreadPool threadPool)`

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`close()`
`void`	`clusterChanged(ClusterChangedEvent event)`	Called when cluster state changes.
`void`	`completePersistentTask(String id, long allocationId, Exception failure, ActionListener<PersistentTasksCustomMetaData.PersistentTask<?>> listener)`	Restarts a record about a running persistent task from cluster state
`<Params extends PersistentTaskParams> void`	`createPersistentTask(String taskId, String taskName, Params taskParams, ActionListener<PersistentTasksCustomMetaData.PersistentTask<?>> listener)`	Creates a new persistent task on master node
`static boolean`	`needsReassignment(PersistentTasksCustomMetaData.Assignment assignment, DiscoveryNodes nodes)`	Returns true if the task is not assigned or is assigned to a non-existing node
`void`	`removePersistentTask(String id, ActionListener<PersistentTasksCustomMetaData.PersistentTask<?>> listener)`	Removes the persistent task
`void`	`setRecheckInterval(TimeValue recheckInterval)`
`void`	`unassignPersistentTask(String taskId, long taskAllocationId, String reason, ActionListener<PersistentTasksCustomMetaData.PersistentTask<?>> listener)`	This unassigns a task from any node, i.e.
`void`	`updatePersistentTaskState(String taskId, long taskAllocationId, PersistentTaskState taskState, ActionListener<PersistentTasksCustomMetaData.PersistentTask<?>> listener)`	Update the state of a persistent task

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

CLUSTER_TASKS_ALLOCATION_RECHECK_INTERVAL_SETTING

public static final Setting<TimeValue> CLUSTER_TASKS_ALLOCATION_RECHECK_INTERVAL_SETTING

Constructor Detail

PersistentTasksClusterService

public PersistentTasksClusterService(Settings settings,
                                     PersistentTasksExecutorRegistry registry,
                                     ClusterService clusterService,
                                     ThreadPool threadPool)

Method Detail

setRecheckInterval

public void setRecheckInterval(TimeValue recheckInterval)

close
```
public void close()
```
Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

createPersistentTask

public <Params extends PersistentTaskParams> void createPersistentTask(String taskId,
                                                                       String taskName,
                                                                       Params taskParams,
                                                                       ActionListener<PersistentTasksCustomMetaData.PersistentTask<?>> listener)

Creates a new persistent task on master node

Parameters:: taskId - the task's id; taskName - the task's name; taskParams - the task's parameters; listener - the listener that will be called when task is started

completePersistentTask

public void completePersistentTask(String id,
                                   long allocationId,
                                   Exception failure,
                                   ActionListener<PersistentTasksCustomMetaData.PersistentTask<?>> listener)

Restarts a record about a running persistent task from cluster state

Parameters:: id - the id of the persistent task; allocationId - the allocation id of the persistent task; failure - the reason for restarting the task or null if the task completed successfully; listener - the listener that will be called when task is removed

removePersistentTask

public void removePersistentTask(String id,
                                 ActionListener<PersistentTasksCustomMetaData.PersistentTask<?>> listener)

Removes the persistent task

Parameters:: id - the id of a persistent task; listener - the listener that will be called when task is removed

updatePersistentTaskState

public void updatePersistentTaskState(String taskId,
                                      long taskAllocationId,
                                      PersistentTaskState taskState,
                                      ActionListener<PersistentTasksCustomMetaData.PersistentTask<?>> listener)

Update the state of a persistent task

Parameters:: taskId - the id of a persistent task; taskAllocationId - the expected allocation id of the persistent task; taskState - new state; listener - the listener that will be called when task is removed

unassignPersistentTask
```
public void unassignPersistentTask(String taskId,
                                   long taskAllocationId,
                                   String reason,
                                   ActionListener<PersistentTasksCustomMetaData.PersistentTask<?>> listener)
```
This unassigns a task from any node, i.e. it is assigned to a null node with the provided reason. Since the assignment executor node is null, the PersistentTasksClusterService will attempt to reassign it to a valid node quickly.

Parameters:

taskId - the id of a persistent task

taskAllocationId - the expected allocation id of the persistent task

reason - the reason for unassigning the task from any node

listener - the listener that will be called when task is unassigned

clusterChanged
```
public void clusterChanged(ClusterChangedEvent event)
```
Description copied from interface: ClusterStateListener

Called when cluster state changes.

Specified by:

clusterChanged in interface ClusterStateListener

needsReassignment

public static boolean needsReassignment(PersistentTasksCustomMetaData.Assignment assignment,
                                        DiscoveryNodes nodes)

Returns true if the task is not assigned or is assigned to a non-existing node

Class PersistentTasksClusterService

Field Summary