/*
* Licensed to Crate under one or more contributor license agreements.
* See the NOTICE file distributed with this work for additional
* information regarding copyright ownership. Crate 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.
*
* However, if you have executed another commercial license agreement
* with Crate these terms will supersede the license and you may use the
* software solely pursuant to the terms of the relevant commercial
* agreement.
*/
package io.crate.operation.reference.sys.node.local;
import io.crate.metadata.ReferenceImplementation;
import org.apache.lucene.util.BytesRef;
import org.elasticsearch.cluster.service.ClusterService;
import org.elasticsearch.cluster.node.DiscoveryNode;
class NodeIdExpression implements ReferenceImplementation<BytesRef> {
private final ClusterService clusterService;
private BytesRef value;
NodeIdExpression(ClusterService clusterService) {
this.clusterService = clusterService;
}
@Override
public BytesRef value() {
DiscoveryNode localNode = clusterService.localNode();
// value could not be ready on node start-up, but is static once set
if (value == null && localNode != null) {
value = new BytesRef(localNode.getId());
}
return value;
}
}