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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.river.routing;
import com.carrotsearch.hppc.cursors.ObjectCursor;
import com.google.common.collect.Lists;
import com.google.common.collect.Maps;
import org.elasticsearch.ElasticsearchException;
import org.elasticsearch.action.NoShardAvailableActionException;
import org.elasticsearch.action.get.GetResponse;
import org.elasticsearch.client.Client;
import org.elasticsearch.cluster.ClusterChangedEvent;
import org.elasticsearch.cluster.ClusterService;
import org.elasticsearch.cluster.ClusterState;
import org.elasticsearch.cluster.ClusterStateListener;
import org.elasticsearch.cluster.block.ClusterBlockException;
import org.elasticsearch.cluster.metadata.IndexMetaData;
import org.elasticsearch.cluster.metadata.MappingMetaData;
import org.elasticsearch.cluster.node.DiscoveryNode;
import org.elasticsearch.common.component.AbstractLifecycleComponent;
import org.elasticsearch.common.inject.Inject;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.common.unit.TimeValue;
import org.elasticsearch.common.util.concurrent.CountDown;
import org.elasticsearch.common.util.concurrent.EsRejectedExecutionException;
import org.elasticsearch.common.xcontent.support.XContentMapValues;
import org.elasticsearch.index.mapper.MapperService;
import org.elasticsearch.index.shard.IllegalIndexShardStateException;
import org.elasticsearch.indices.IndexMissingException;
import org.elasticsearch.river.RiverIndexName;
import org.elasticsearch.river.RiverName;
import org.elasticsearch.river.cluster.RiverClusterService;
import org.elasticsearch.river.cluster.RiverClusterState;
import org.elasticsearch.river.cluster.RiverClusterStateUpdateTask;
import org.elasticsearch.river.cluster.RiverNodeHelper;
import org.elasticsearch.threadpool.ThreadPool;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
/**
*
*/
public class RiversRouter extends AbstractLifecycleComponent<RiversRouter> implements ClusterStateListener {
private static final TimeValue RIVER_START_RETRY_INTERVAL = TimeValue.timeValueMillis(1000);
private static final int RIVER_START_MAX_RETRIES = 5;
private final String riverIndexName;
private final Client client;
private final RiverClusterService riverClusterService;
private final ThreadPool threadPool;
@Inject
public RiversRouter(Settings settings, Client client, ClusterService clusterService, RiverClusterService riverClusterService, ThreadPool threadPool) {
super(settings);
this.riverIndexName = RiverIndexName.Conf.indexName(settings);
this.riverClusterService = riverClusterService;
this.client = client;
this.threadPool = threadPool;
clusterService.add(this);
}
@Override
protected void doStart() throws ElasticsearchException {
}
@Override
protected void doStop() throws ElasticsearchException {
}
@Override
protected void doClose() throws ElasticsearchException {
}
@Override
public void clusterChanged(final ClusterChangedEvent event) {
if (!event.localNodeMaster()) {
return;
}
final String source = "reroute_rivers_node_changed";
//we'll try again a few times if we don't find the river _meta document while the type is there
final CountDown countDown = new CountDown(RIVER_START_MAX_RETRIES);
riverClusterService.submitStateUpdateTask(source, new RiverClusterStateUpdateTask() {
@Override
public RiverClusterState execute(RiverClusterState currentState) {
return updateRiverClusterState(source, currentState, event.state(), countDown);
}
});
}
protected RiverClusterState updateRiverClusterState(final String source, final RiverClusterState currentState,
ClusterState newClusterState, final CountDown countDown) {
if (!newClusterState.metaData().hasIndex(riverIndexName)) {
// if there are routings, publish an empty one (so it will be deleted on nodes), otherwise, return the same state
if (!currentState.routing().isEmpty()) {
return RiverClusterState.builder().state(currentState).routing(RiversRouting.builder()).build();
}
return currentState;
}
RiversRouting.Builder routingBuilder = RiversRouting.builder().routing(currentState.routing());
boolean dirty = false;
IndexMetaData indexMetaData = newClusterState.metaData().index(riverIndexName);
boolean metaFound = true;
// go over and create new river routing (with no node) for new types (rivers names)
for (ObjectCursor<MappingMetaData> cursor : indexMetaData.mappings().values()) {
String mappingType = cursor.value.type(); // mapping type is the name of the river
if (MapperService.DEFAULT_MAPPING.equals(mappingType)) {
continue;
}
if (!currentState.routing().hasRiverByName(mappingType)) {
// no river, we need to add it to the routing with no node allocation
try {
GetResponse getResponse = client.prepareGet(riverIndexName, mappingType, "_meta").setPreference("_primary").get();
if (getResponse.isExists()) {
logger.debug("{}/{}/_meta document found.", riverIndexName, mappingType);
String riverType = XContentMapValues.nodeStringValue(getResponse.getSourceAsMap().get("type"), null);
if (riverType == null) {
logger.warn("no river type provided for [{}], ignoring...", riverIndexName);
} else {
routingBuilder.put(new RiverRouting(new RiverName(riverType, mappingType), null));
dirty = true;
}
} else {
// At least one type does not have _meta
metaFound = false;
}
} catch (NoShardAvailableActionException e) {
// ignore, we will get it next time...
} catch (ClusterBlockException e) {
// ignore, we will get it next time
} catch (IndexMissingException e) {
// ignore, we will get it next time
} catch (IllegalIndexShardStateException e) {
// ignore, we will get it next time
} catch (Exception e) {
logger.warn("failed to get/parse _meta for [{}]", e, mappingType);
}
}
}
// At least one type does not have _meta, so we are
// going to reschedule some checks
if (!metaFound) {
if (countDown.countDown()) {
logger.warn("no river _meta document found after {} attempts", RIVER_START_MAX_RETRIES);
} else {
logger.debug("no river _meta document found retrying in {} ms", RIVER_START_RETRY_INTERVAL.millis());
try {
threadPool.schedule(RIVER_START_RETRY_INTERVAL, ThreadPool.Names.GENERIC, new Runnable() {
@Override
public void run() {
riverClusterService.submitStateUpdateTask(source, new RiverClusterStateUpdateTask() {
@Override
public RiverClusterState execute(RiverClusterState currentState) {
return updateRiverClusterState(source, currentState, riverClusterService.state(), countDown);
}
});
}
});
} catch (EsRejectedExecutionException ex) {
logger.debug("Couldn't schedule river start retry, node might be shutting down", ex);
}
}
}
// now, remove routings that were deleted
// also, apply nodes that were removed and rivers were running on
for (RiverRouting routing : currentState.routing()) {
if (!indexMetaData.mappings().containsKey(routing.riverName().name())) {
routingBuilder.remove(routing);
dirty = true;
} else if (routing.node() != null && !newClusterState.nodes().nodeExists(routing.node().id())) {
routingBuilder.remove(routing);
routingBuilder.put(new RiverRouting(routing.riverName(), null));
dirty = true;
}
}
// build a list from nodes to rivers
Map<DiscoveryNode, List<RiverRouting>> nodesToRivers = Maps.newHashMap();
for (DiscoveryNode node : newClusterState.nodes()) {
if (RiverNodeHelper.isRiverNode(node)) {
nodesToRivers.put(node, Lists.<RiverRouting>newArrayList());
}
}
List<RiverRouting> unassigned = Lists.newArrayList();
for (RiverRouting routing : routingBuilder.build()) {
if (routing.node() == null) {
unassigned.add(routing);
} else {
List<RiverRouting> l = nodesToRivers.get(routing.node());
if (l == null) {
l = Lists.newArrayList();
nodesToRivers.put(routing.node(), l);
}
l.add(routing);
}
}
for (Iterator<RiverRouting> it = unassigned.iterator(); it.hasNext(); ) {
RiverRouting routing = it.next();
DiscoveryNode smallest = null;
int smallestSize = Integer.MAX_VALUE;
for (Map.Entry<DiscoveryNode, List<RiverRouting>> entry : nodesToRivers.entrySet()) {
if (RiverNodeHelper.isRiverNode(entry.getKey(), routing.riverName())) {
if (entry.getValue().size() < smallestSize) {
smallestSize = entry.getValue().size();
smallest = entry.getKey();
}
}
}
if (smallest != null) {
dirty = true;
it.remove();
routing.node(smallest);
nodesToRivers.get(smallest).add(routing);
logger.debug("going to allocate river [{}] on node {}", routing.riverName().getName(), smallest);
}
}
// add relocation logic...
if (dirty) {
return RiverClusterState.builder().state(currentState).routing(routingBuilder).build();
}
return currentState;
}
}