Package io.fabric8.kubernetes.client.extended.leaderelection

Class LeaderElector

java.lang.Object

io.fabric8.kubernetes.client.extended.leaderelection.LeaderElector

public class LeaderElector
extends Object

Field Summary

Fields

Modifier and Type	Field	Description
protected static Double	JITTER_FACTOR

Constructor Summary

Constructors

Constructor	Description
LeaderElector(KubernetesClient kubernetesClient, LeaderElectionConfig leaderElectionConfig, Executor executor)

Method Summary

Modifier and Type	Method	Description
protected boolean	canBecomeLeader(LeaderElectionRecord leaderElectionRecord)
protected boolean	isLeader(LeaderElectionRecord leaderElectionRecord)
protected static Duration	jitter(Duration duration, double maxFactor)	Returns a Duration between the provided duration and (duration + maxFactor*duration)
protected static CompletableFuture<Void>	loop(Consumer<CompletableFuture<?>> consumer, LongSupplier delaySupplier, Executor executor)	Periodically (every provided period) runs the provided Consumer in a separate thread until the supplied CompletableFuture is completed.
protected static ZonedDateTime	now()
boolean	release()	Release the leadership if currently held.
void	run()	Starts the leader election loop.
CompletableFuture<?>	start()	Start a leader elector.

Methods inherited from class java.lang.Object

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

Field Detail

JITTER_FACTOR

protected static final Double JITTER_FACTOR

Constructor Detail

LeaderElector

public LeaderElector(KubernetesClient kubernetesClient,
                     LeaderElectionConfig leaderElectionConfig,
                     Executor executor)

Method Detail

run

public void run()

Starts the leader election loop. May only be run once.

start() is preferred as it does not hold a thread.

start

public CompletableFuture<?> start()

Start a leader elector. The future may be cancelled to stop the leader elector. May only be run once.

Returns:

the future

release

public boolean release()

Release the leadership if currently held. If not cancelled, the elector will continue to try and re-acquire the lock.

Returns:

true if the lock was successfully released. false if there is no lock, or this is not the leader

isLeader

protected final boolean isLeader(LeaderElectionRecord leaderElectionRecord)

canBecomeLeader

protected final boolean canBecomeLeader(LeaderElectionRecord leaderElectionRecord)

loop

protected static CompletableFuture<Void> loop(Consumer<CompletableFuture<?>> consumer,
                                              LongSupplier delaySupplier,
                                              Executor executor)

Periodically (every provided period) runs the provided Consumer in a separate thread until the supplied CompletableFuture is completed.

Parameters:

consumer - function to run in a separate thread

delaySupplier - to schedule the run of the provided consumer

Returns:

the future to be completed

now

protected static ZonedDateTime now()

jitter

protected static Duration jitter(Duration duration,
                                 double maxFactor)

Returns a Duration between the provided duration and (duration + maxFactor*duration)

Parameters:

duration - to apply jitter to

maxFactor - for jitter

Returns:

the jittered duration