org.apache.twill.api

Interface TwillController

All Superinterfaces:

ServiceController

public interface TwillController
extends ServiceController

For controlling a running application.

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.twill.api.ServiceController

ServiceController.TerminationStatus

Method Summary

Modifier and Type	Method and Description
void	addLogHandler(LogHandler handler) Adds a LogHandler for receiving application log.
Future<Integer>	changeInstances(String runnable, int newCount) Changes the number of running instances of a given runnable.
ServiceDiscovered	discoverService(String serviceName) Discovers the set of Discoverable endpoints that provides service for the given service name.
ResourceReport	getResourceReport() Get a snapshot of the resources used by the application, broken down by each runnable.
Future<String[]>	resetLogLevels(String... loggerNames) Reset the log levels of all runnables.
Future<String[]>	resetRunnableLogLevels(String runnableName, String... loggerNames) Reset the log levels of the given runnable.
Future<String>	restartAllInstances(String runnable) Restart all instances of a particular TwillRunnable.
Future<Set<String>>	restartInstances(Map<String,? extends Set<Integer>> runnableToInstanceIds) Restart instances of some TwillRunnable.
Future<String>	restartInstances(String runnable, int instanceId, int... moreInstanceIds) Restart instances of some TwillRunnable.
Future<String>	restartInstances(String runnable, Set<Integer> instanceIds) Restart instances of some TwillRunnable.
Future<Map<String,LogEntry.Level>>	updateLogLevels(Map<String,LogEntry.Level> logLevels) Update the log levels for requested logger names for Twill applications running in a container.
Future<Map<String,LogEntry.Level>>	updateLogLevels(String runnableName, Map<String,LogEntry.Level> logLevelsForRunnable) Update the log levels for requested logger names for a TwillRunnable.

Methods inherited from interface org.apache.twill.api.ServiceController

awaitTerminated, awaitTerminated, getRunId, getTerminationStatus, kill, onRunning, onTerminated, sendCommand, sendCommand, terminate

Method Detail

addLogHandler

void addLogHandler(LogHandler handler)

Adds a LogHandler for receiving application log.

Parameters:

handler - The handler to add.

discoverService

ServiceDiscovered discoverService(String serviceName)

Discovers the set of Discoverable endpoints that provides service for the given service name.

Parameters:

serviceName - Name of the service to discovery.

Returns:

A ServiceDiscovered object representing the result.

changeInstances

Future<Integer> changeInstances(String runnable,
                                int newCount)

Changes the number of running instances of a given runnable.

Parameters:

runnable - The name of the runnable.

newCount - Number of instances for the given runnable.

Returns:

A Future that will be completed when the number running instances has been successfully changed. The future will carry the new count as the result. If there is any error while changing instances, it'll be reflected in the future.

getResourceReport

@Nullable
ResourceReport getResourceReport()

Get a snapshot of the resources used by the application, broken down by each runnable.

Returns:

A ResourceReport containing information about resources used by the application or null in case the user calls this before the application completely starts.

restartAllInstances

Future<String> restartAllInstances(String runnable)

Restart all instances of a particular TwillRunnable.

Parameters:

runnable - The name of the runnable to restart.

Returns:

A Future that will be completed when the restart operation has been done.

restartInstances

Future<Set<String>> restartInstances(Map<String,? extends Set<Integer>> runnableToInstanceIds)

Restart instances of some TwillRunnable.

Parameters:

runnableToInstanceIds - A map of runnable ID to list of instance IDs to be restarted.

Returns:

A Future that will be completed when the restart operation has been done.

restartInstances

Future<String> restartInstances(String runnable,
                                int instanceId,
                                int... moreInstanceIds)

Restart instances of some TwillRunnable.

Parameters:

runnable - The name of the runnable to restart.

instanceId - The main instance id to be restarted.

moreInstanceIds - The optional instance ids.

Returns:

A Future that will be completed when the restart operation has been done.

restartInstances

Future<String> restartInstances(String runnable,
                                Set<Integer> instanceIds)

Restart instances of some TwillRunnable.

Parameters:

runnable - The name of the runnable to restart.

instanceIds - Instances to be restarted

Returns:

A Future that will be completed when the restart operation has been done.

updateLogLevels

Future<Map<String,LogEntry.Level>> updateLogLevels(Map<String,LogEntry.Level> logLevels)

Update the log levels for requested logger names for Twill applications running in a container. The log level for a logger name can be null except for the root logger, which will reset the log level for the specified logger.

Parameters:

logLevels - The Map contains the requested logger names and log levels that need to be updated.

Returns:

A Future that will be completed when the log level update has been done. It will carry the Map of log levels as the result.

updateLogLevels

Future<Map<String,LogEntry.Level>> updateLogLevels(String runnableName,
                                                   Map<String,LogEntry.Level> logLevelsForRunnable)

Update the log levels for requested logger names for a TwillRunnable. The log level for a logger name can be null except for the root logger, which will reset the log level for the specified logger.

Parameters:

runnableName - The name of the runnable to update the log level.

logLevelsForRunnable - The Map contains the requested logger name and log level that need to be updated.

Returns:

A Future that will be completed when the log level update has been done. It will carry the Map of log levels as the result.

resetLogLevels

Future<String[]> resetLogLevels(String... loggerNames)

Reset the log levels of all runnables. The log levels will be the same as when the runnables start up.

Parameters:

loggerNames - The optional logger names to be reset for all runnables, if not provided, all log levels will be reset.

Returns:

A Future that will be completed when the set log level operation has been done. The future result is the logger names provided in the parameter.

resetRunnableLogLevels

Future<String[]> resetRunnableLogLevels(String runnableName,
                                        String... loggerNames)

Reset the log levels of the given runnable. The log levels will be same as when the runnable starts up.

Parameters:

loggerNames - The optional logger names to be reset for the runnable, if not provided, all log levels will be reset.

Returns:

A Future that will be completed when the set log level operation has been done. The future result is the logger names provided in the parameter.