Package org.apache.drill.yarn.appMaster

Class DrillControllerFactory

java.lang.Object

org.apache.drill.yarn.appMaster.DrillControllerFactory

All Implemented Interfaces:

ControllerFactory

public class DrillControllerFactory
extends Object
implements ControllerFactory

Builds a controller for a cluster of Drillbits. The AM is designed to be mostly generic; only this class contains knowledge that the tasks being managed are drillbits. This design ensures that we can add other Drill components in the future without the need to make major changes to the AM logic.

The controller consists of a generic dispatcher and cluster controller, along with a Drill-specific scheduler and task launch specification. Drill also includes an interface to ZooKeeper to monitor Drillbits.

The AM is launched by YARN. All it knows is what is in its launch environment or configuration files. The client must set up all the information that the AM needs. Static information appears in configuration files. But, dynamic information (or that which is inconvenient to repeat in configuration files) must arrive in environment variables. See DrillOnYarnConfig for more information.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	DrillControllerFactory.ZKRegistryAddOn

Nested classes/interfaces inherited from interface org.apache.drill.yarn.appMaster.ControllerFactory

ControllerFactory.ControllerFactoryException

Constructor Summary

Constructors

Constructor	Description
DrillControllerFactory()

Method Summary

Modifier and Type	Method	Description
void	addIfSet(LaunchSpec spec, String configParam, String envVar)	Utility method to create an environment variable in the process launch specification if a given Drill-on-YARN configuration variable is set, copying the config value to the environment variable.
Dispatcher	build()

Methods inherited from class java.lang.Object

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

Constructor Details

DrillControllerFactory

public DrillControllerFactory()

Method Details

build

public Dispatcher build()
                 throws ControllerFactory.ControllerFactoryException

Specified by:

build in interface ControllerFactory

Throws:

ControllerFactory.ControllerFactoryException

addIfSet

public void addIfSet(LaunchSpec spec,
 String configParam,
 String envVar)

Utility method to create an environment variable in the process launch specification if a given Drill-on-YARN configuration variable is set, copying the config value to the environment variable.

Parameters:

spec - launch specification

configParam - config value

envVar - environment variable