org.elasticsearch.cluster.MasterNodeChangePredicate Maven / Gradle / Ivy
/*
* Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
* or more contributor license agreements. Licensed under the Elastic License
* 2.0 and the Server Side Public License, v 1; you may not use this file except
* in compliance with, at your election, the Elastic License 2.0 or the Server
* Side Public License, v 1.
*/
package org.elasticsearch.cluster;
import org.elasticsearch.cluster.node.DiscoveryNode;
import java.util.function.Predicate;
public final class MasterNodeChangePredicate {
private MasterNodeChangePredicate() {
}
/**
* builds a predicate that will accept a cluster state only if it was generated after the current has
* (re-)joined the master
*/
public static Predicate build(ClusterState currentState) {
final long currentVersion = currentState.version();
final DiscoveryNode masterNode = currentState.nodes().getMasterNode();
final String currentMasterId = masterNode == null ? null : masterNode.getEphemeralId();
return newState -> {
final DiscoveryNode newMaster = newState.nodes().getMasterNode();
final boolean accept;
if (newMaster == null) {
accept = false;
} else if (newMaster.getEphemeralId().equals(currentMasterId) == false) {
accept = true;
} else {
accept = newState.version() > currentVersion;
}
return accept;
};
}
}