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* Licensed to Elasticsearch under one or more contributor
* license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright
* ownership. Elasticsearch licenses this file to you under
* the Apache License, Version 2.0 (the "License"); you may
* not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.elasticsearch.cluster.routing.allocation.decider;
import org.elasticsearch.cluster.routing.MutableShardRouting;
import org.elasticsearch.cluster.routing.RoutingNode;
import org.elasticsearch.cluster.routing.ShardRouting;
import org.elasticsearch.cluster.routing.allocation.RoutingAllocation;
import org.elasticsearch.common.inject.Inject;
import org.elasticsearch.common.settings.Settings;
/**
* An allocation strategy that only allows for a replica to be allocated when the primary is active.
*/
public class ReplicaAfterPrimaryActiveAllocationDecider extends AllocationDecider {
private static final String NAME = "replica_after_primary_active";
@Inject
public ReplicaAfterPrimaryActiveAllocationDecider(Settings settings) {
super(settings);
}
@Override
public Decision canAllocate(ShardRouting shardRouting, RoutingNode node, RoutingAllocation allocation) {
return canAllocate(shardRouting, allocation);
}
public Decision canAllocate(ShardRouting shardRouting, RoutingAllocation allocation) {
if (shardRouting.primary()) {
return allocation.decision(Decision.YES, NAME, "shard is primary");
}
MutableShardRouting primary = allocation.routingNodes().activePrimary(shardRouting);
if (primary == null) {
return allocation.decision(Decision.NO, NAME, "primary shard is not yet active");
}
return allocation.decision(Decision.YES, NAME, "primary is already active");
}
}