org.apache.storm.nimbus

Class AssignmentDistributionService

java.lang.Object

org.apache.storm.nimbus.AssignmentDistributionService

All Implemented Interfaces:

Closeable, AutoCloseable

public class AssignmentDistributionService
extends Object
implements Closeable

A service for distributing master assignments to supervisors, this service makes the assignments notification asynchronous.

We support multiple working threads to distribute assignment, every thread has a queue buffer.

Master will shuffle its node request to the queues, if the target queue is full, we just discard the request, let the supervisors sync instead.

Caution: this class is not thread safe.

Working mode
                     +--------+         +-----------------+
                     | queue1 |   ==>   | Working thread1 |
+--------+ shuffle   +--------+         +-----------------+
| Master |   ==>
+--------+           +--------+         +-----------------+
                     | queue2 |   ==>   | Working thread2 |
                     +--------+         +-----------------+

Constructor Summary

Constructors

Constructor and Description
AssignmentDistributionService()

Method Summary

Modifier and Type	Method and Description
void	addAssignmentsForNode(String node, String host, Integer serverPort, SupervisorAssignments assignments) Add an assignments for a node/supervisor for distribution.
void	addLocalSupervisor(Supervisor supervisor)
void	close()
Map	getConf()
static AssignmentDistributionService	getInstance(Map conf) Factory method for initialize a instance.
boolean	isActive()
org.apache.storm.nimbus.AssignmentDistributionService.NodeAssignments	nextAssignments(Integer queueIndex) Get an assignments from the target queue with the specific index.
void	prepare(Map conf) Function for initialization.

Methods inherited from class java.lang.Object

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

Constructor Detail

AssignmentDistributionService

public AssignmentDistributionService()

Method Detail

getInstance

public static AssignmentDistributionService getInstance(Map conf)

Factory method for initialize a instance.

Parameters:

conf - config.

Returns:

an instance of AssignmentDistributionService

prepare

public void prepare(Map conf)

Function for initialization.

Parameters:

conf - config

close

public void close()
           throws IOException

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Throws:

IOException

addAssignmentsForNode

public void addAssignmentsForNode(String node,
                                  String host,
                                  Integer serverPort,
                                  SupervisorAssignments assignments)

Add an assignments for a node/supervisor for distribution.

Parameters:

node - node id of supervisor.

host - host name for the node.

serverPort - node thrift server port.

assignments - the SupervisorAssignments

addLocalSupervisor

public void addLocalSupervisor(Supervisor supervisor)

nextAssignments

public org.apache.storm.nimbus.AssignmentDistributionService.NodeAssignments nextAssignments(Integer queueIndex)
                                                                                      throws InterruptedException

Get an assignments from the target queue with the specific index.

Parameters:

queueIndex - index of the queue

Returns:

an NodeAssignments

Throws:

InterruptedException

isActive

public boolean isActive()

getConf

public Map getConf()