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* 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.
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package org.elasticsearch.cluster.routing.allocation.decider;
import org.elasticsearch.cluster.metadata.IndexMetaData;
import org.elasticsearch.cluster.node.DiscoveryNodeFilters;
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;
import org.elasticsearch.node.settings.NodeSettingsService;
import java.util.Map;
import static org.elasticsearch.cluster.node.DiscoveryNodeFilters.OpType.AND;
import static org.elasticsearch.cluster.node.DiscoveryNodeFilters.OpType.OR;
/**
* This {@link AllocationDecider} control shard allocation by include and
* exclude filters via dynamic cluster and index routing settings.
* <p>
* This filter is used to make explicit decision on which nodes certain shard
* can / should be allocated. The decision if a shard can be allocated, must not
* be allocated or should be allocated is based on either cluster wide dynamic
* settings (<tt>cluster.routing.allocation.*</tt>) or index specific dynamic
* settings (<tt>index.routing.allocation.*</tt>). All of those settings can be
* changed at runtime via the cluster or the index update settings API.
* </p>
* Note: Cluster settings are applied first and will override index specific
* settings such that if a shard can be allocated according to the index routing
* settings it wont be allocated on a node if the cluster specific settings
* would disallow the allocation. Filters are applied in the following order:
* <ol>
* <li><tt>required</tt> - filters required allocations.
* If any <tt>required</tt> filters are set the allocation is denied if the index is <b>not</b> in the set of <tt>required</tt> to allocate on the filtered node</li>
* <li><tt>include</tt> - filters "allowed" allocations.
* If any <tt>include</tt> filters are set the allocation is denied if the index is <b>not</b> in the set of <tt>include</tt> filters for the filtered node</li>
* <li><tt>exclude</tt> - filters "prohibited" allocations.
* If any <tt>exclude</tt> filters are set the allocation is denied if the index is in the set of <tt>exclude</tt> filters for the filtered node</li>
* </ol>
*/
public class FilterAllocationDecider extends AllocationDecider {
public static final String NAME = "filter";
public static final String INDEX_ROUTING_REQUIRE_GROUP = "index.routing.allocation.require.";
public static final String INDEX_ROUTING_INCLUDE_GROUP = "index.routing.allocation.include.";
public static final String INDEX_ROUTING_EXCLUDE_GROUP = "index.routing.allocation.exclude.";
public static final String CLUSTER_ROUTING_REQUIRE_GROUP = "cluster.routing.allocation.require.";
public static final String CLUSTER_ROUTING_INCLUDE_GROUP = "cluster.routing.allocation.include.";
public static final String CLUSTER_ROUTING_EXCLUDE_GROUP = "cluster.routing.allocation.exclude.";
private volatile DiscoveryNodeFilters clusterRequireFilters;
private volatile DiscoveryNodeFilters clusterIncludeFilters;
private volatile DiscoveryNodeFilters clusterExcludeFilters;
@Inject
public FilterAllocationDecider(Settings settings, NodeSettingsService nodeSettingsService) {
super(settings);
Map<String, String> requireMap = settings.getByPrefix(CLUSTER_ROUTING_REQUIRE_GROUP).getAsMap();
if (requireMap.isEmpty()) {
clusterRequireFilters = null;
} else {
clusterRequireFilters = DiscoveryNodeFilters.buildFromKeyValue(AND, requireMap);
}
Map<String, String> includeMap = settings.getByPrefix(CLUSTER_ROUTING_INCLUDE_GROUP).getAsMap();
if (includeMap.isEmpty()) {
clusterIncludeFilters = null;
} else {
clusterIncludeFilters = DiscoveryNodeFilters.buildFromKeyValue(OR, includeMap);
}
Map<String, String> excludeMap = settings.getByPrefix(CLUSTER_ROUTING_EXCLUDE_GROUP).getAsMap();
if (excludeMap.isEmpty()) {
clusterExcludeFilters = null;
} else {
clusterExcludeFilters = DiscoveryNodeFilters.buildFromKeyValue(OR, excludeMap);
}
nodeSettingsService.addListener(new ApplySettings());
}
@Override
public Decision canAllocate(ShardRouting shardRouting, RoutingNode node, RoutingAllocation allocation) {
return shouldFilter(shardRouting, node, allocation);
}
@Override
public Decision canAllocate(IndexMetaData indexMetaData, RoutingNode node, RoutingAllocation allocation) {
return shouldFilter(indexMetaData, node, allocation);
}
@Override
public Decision canRemain(ShardRouting shardRouting, RoutingNode node, RoutingAllocation allocation) {
return shouldFilter(shardRouting, node, allocation);
}
private Decision shouldFilter(ShardRouting shardRouting, RoutingNode node, RoutingAllocation allocation) {
Decision decision = shouldClusterFilter(node, allocation);
if (decision != null) return decision;
decision = shouldIndexFilter(allocation.routingNodes().metaData().index(shardRouting.index()), node, allocation);
if (decision != null) return decision;
return allocation.decision(Decision.YES, NAME, "node passes include/exclude/require filters");
}
private Decision shouldFilter(IndexMetaData indexMd, RoutingNode node, RoutingAllocation allocation) {
Decision decision = shouldClusterFilter(node, allocation);
if (decision != null) return decision;
decision = shouldIndexFilter(indexMd, node, allocation);
if (decision != null) return decision;
return allocation.decision(Decision.YES, NAME, "node passes include/exclude/require filters");
}
private Decision shouldIndexFilter(IndexMetaData indexMd, RoutingNode node, RoutingAllocation allocation) {
if (indexMd.requireFilters() != null) {
if (!indexMd.requireFilters().match(node.node())) {
return allocation.decision(Decision.NO, NAME, "node does not match index required filters [%s]", indexMd.requireFilters());
}
}
if (indexMd.includeFilters() != null) {
if (!indexMd.includeFilters().match(node.node())) {
return allocation.decision(Decision.NO, NAME, "node does not match index include filters [%s]", indexMd.includeFilters());
}
}
if (indexMd.excludeFilters() != null) {
if (indexMd.excludeFilters().match(node.node())) {
return allocation.decision(Decision.NO, NAME, "node matches index exclude filters [%s]", indexMd.excludeFilters());
}
}
return null;
}
private Decision shouldClusterFilter(RoutingNode node, RoutingAllocation allocation) {
if (clusterRequireFilters != null) {
if (!clusterRequireFilters.match(node.node())) {
return allocation.decision(Decision.NO, NAME, "node does not match global required filters [%s]", clusterRequireFilters);
}
}
if (clusterIncludeFilters != null) {
if (!clusterIncludeFilters.match(node.node())) {
return allocation.decision(Decision.NO, NAME, "node does not match global include filters [%s]", clusterIncludeFilters);
}
}
if (clusterExcludeFilters != null) {
if (clusterExcludeFilters.match(node.node())) {
return allocation.decision(Decision.NO, NAME, "node matches global exclude filters [%s]", clusterExcludeFilters);
}
}
return null;
}
class ApplySettings implements NodeSettingsService.Listener {
@Override
public void onRefreshSettings(Settings settings) {
Map<String, String> requireMap = settings.getByPrefix(CLUSTER_ROUTING_REQUIRE_GROUP).getAsMap();
if (!requireMap.isEmpty()) {
clusterRequireFilters = DiscoveryNodeFilters.buildFromKeyValue(AND, requireMap);
}
Map<String, String> includeMap = settings.getByPrefix(CLUSTER_ROUTING_INCLUDE_GROUP).getAsMap();
if (!includeMap.isEmpty()) {
clusterIncludeFilters = DiscoveryNodeFilters.buildFromKeyValue(OR, includeMap);
}
Map<String, String> excludeMap = settings.getByPrefix(CLUSTER_ROUTING_EXCLUDE_GROUP).getAsMap();
if (!excludeMap.isEmpty()) {
clusterExcludeFilters = DiscoveryNodeFilters.buildFromKeyValue(OR, excludeMap);
}
}
}
}