/*
* Licensed to ElasticSearch and Shay Banon 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.node.settings;
import org.elasticsearch.cluster.ClusterChangedEvent;
import org.elasticsearch.cluster.ClusterService;
import org.elasticsearch.cluster.ClusterStateListener;
import org.elasticsearch.common.component.AbstractComponent;
import org.elasticsearch.common.inject.Inject;
import org.elasticsearch.common.logging.ESLoggerFactory;
import org.elasticsearch.common.settings.Settings;
import java.util.Map;
import java.util.concurrent.CopyOnWriteArrayList;
/**
* A service that allows to register for node settings change that can come from cluster
* events holding new settings.
*/
public class NodeSettingsService extends AbstractComponent implements ClusterStateListener {
private volatile Settings lastSettingsApplied;
private final CopyOnWriteArrayList<Listener> listeners = new CopyOnWriteArrayList<Listener>();
@Inject
public NodeSettingsService(Settings settings) {
super(settings);
}
// inject it as a member, so we won't get into possible cyclic problems
public void setClusterService(ClusterService clusterService) {
clusterService.add(this);
}
@Override
public void clusterChanged(ClusterChangedEvent event) {
// nothing to do until we actually recover from the gateway or any other block indicates we need to disable persistency
if (event.state().blocks().disableStatePersistence()) {
return;
}
if (!event.metaDataChanged()) {
// nothing changed in the metadata, no need to check
return;
}
if (lastSettingsApplied != null && event.state().metaData().settings().equals(lastSettingsApplied)) {
// nothing changed in the settings, ignore
return;
}
for (Listener listener : listeners) {
try {
listener.onRefreshSettings(event.state().metaData().settings());
} catch (Exception e) {
logger.warn("failed to refresh settings for [{}]", e, listener);
}
}
try {
for (Map.Entry<String, String> entry : event.state().metaData().settings().getAsMap().entrySet()) {
if (entry.getKey().startsWith("logger.")) {
String component = entry.getKey().substring("logger.".length());
ESLoggerFactory.getLogger(component, entry.getValue()).setLevel(entry.getValue());
}
}
} catch (Exception e) {
logger.warn("failed to refresh settings for [{}]", e, "logger");
}
lastSettingsApplied = event.state().metaData().settings();
}
public void addListener(Listener listener) {
this.listeners.add(listener);
}
public void removeListener(Listener listener) {
this.listeners.remove(listener);
}
public static interface Listener {
void onRefreshSettings(Settings settings);
}
}