org.elasticsearch.cluster.routing.allocation.command.AllocateAllocationCommand Maven / Gradle / Ivy
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* Licensed to ElasticSearch and Shay Banon under one
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* 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.command;
import org.elasticsearch.ElasticSearchException;
import org.elasticsearch.ElasticSearchIllegalArgumentException;
import org.elasticsearch.ElasticSearchParseException;
import org.elasticsearch.cluster.node.DiscoveryNode;
import org.elasticsearch.cluster.routing.MutableShardRouting;
import org.elasticsearch.cluster.routing.RoutingNode;
import org.elasticsearch.cluster.routing.allocation.RoutingAllocation;
import org.elasticsearch.cluster.routing.allocation.decider.Decision;
import org.elasticsearch.common.io.stream.StreamInput;
import org.elasticsearch.common.io.stream.StreamOutput;
import org.elasticsearch.common.xcontent.ToXContent;
import org.elasticsearch.common.xcontent.XContentBuilder;
import org.elasticsearch.common.xcontent.XContentParser;
import org.elasticsearch.index.shard.ShardId;
import java.io.IOException;
import java.util.Iterator;
/**
* Allocates an unassigned shard to a specific node. Note, primary allocation will "force"
* allocation which might mean one will loose data if using local gateway..., use with care
* with the allowPrimary flag.
*/
public class AllocateAllocationCommand implements AllocationCommand {
public static final String NAME = "allocate";
public static class Factory implements AllocationCommand.Factory {
@Override
public AllocateAllocationCommand readFrom(StreamInput in) throws IOException {
return new AllocateAllocationCommand(ShardId.readShardId(in), in.readString(), in.readBoolean());
}
@Override
public void writeTo(AllocateAllocationCommand command, StreamOutput out) throws IOException {
command.shardId().writeTo(out);
out.writeString(command.node());
out.writeBoolean(command.allowPrimary());
}
@Override
public AllocateAllocationCommand fromXContent(XContentParser parser) throws IOException {
String index = null;
int shardId = -1;
String nodeId = null;
boolean allowPrimary = false;
String currentFieldName = null;
XContentParser.Token token;
while ((token = parser.nextToken()) != XContentParser.Token.END_OBJECT) {
if (token == XContentParser.Token.FIELD_NAME) {
currentFieldName = parser.currentName();
} else if (token.isValue()) {
if ("index".equals(currentFieldName)) {
index = parser.text();
} else if ("shard".equals(currentFieldName)) {
shardId = parser.intValue();
} else if ("node".equals(currentFieldName)) {
nodeId = parser.text();
} else if ("allow_primary".equals(currentFieldName) || "allowPrimary".equals(currentFieldName)) {
allowPrimary = parser.booleanValue();
} else {
throw new ElasticSearchParseException("[allocate] command does not support field [" + currentFieldName + "]");
}
} else {
throw new ElasticSearchParseException("[allocate] command does not support complex json tokens [" + token + "]");
}
}
if (index == null) {
throw new ElasticSearchParseException("[allocate] command missing the index parameter");
}
if (shardId == -1) {
throw new ElasticSearchParseException("[allocate] command missing the shard parameter");
}
if (nodeId == null) {
throw new ElasticSearchParseException("[allocate] command missing the node parameter");
}
return new AllocateAllocationCommand(new ShardId(index, shardId), nodeId, allowPrimary);
}
@Override
public void toXContent(AllocateAllocationCommand command, XContentBuilder builder, ToXContent.Params params) throws IOException {
builder.startObject();
builder.field("index", command.shardId().index());
builder.field("shard", command.shardId().id());
builder.field("node", command.node());
builder.field("allow_primary", command.allowPrimary());
builder.endObject();
}
}
private final ShardId shardId;
private final String node;
private final boolean allowPrimary;
/**
* Create a new {@link AllocateAllocationCommand}
*
* @param shardId {@link ShardId} of the shrad to assign
* @param node Node to assign the shard to
* @param allowPrimary should the node be allow to allocate the shard as primary
*/
public AllocateAllocationCommand(ShardId shardId, String node, boolean allowPrimary) {
this.shardId = shardId;
this.node = node;
this.allowPrimary = allowPrimary;
}
@Override
public String name() {
return NAME;
}
/**
* Get the shards id
*
* @return id of the shard
*/
public ShardId shardId() {
return this.shardId;
}
/**
* Get the id of the Node
*
* @return id of the Node
*/
public String node() {
return this.node;
}
/**
* Determine if primary allocation is allowed
*
* @return true if primary allocation is allowed. Otherwise false
*/
public boolean allowPrimary() {
return this.allowPrimary;
}
@Override
public void execute(RoutingAllocation allocation) throws ElasticSearchException {
DiscoveryNode discoNode = allocation.nodes().resolveNode(node);
MutableShardRouting shardRouting = null;
for (MutableShardRouting routing : allocation.routingNodes().unassigned()) {
if (routing.shardId().equals(shardId)) {
// prefer primaries first to allocate
if (shardRouting == null || routing.primary()) {
shardRouting = routing;
}
}
}
if (shardRouting == null) {
throw new ElasticSearchIllegalArgumentException("[allocate] failed to find " + shardId + " on the list of unassigned shards");
}
if (shardRouting.primary() && !allowPrimary) {
throw new ElasticSearchIllegalArgumentException("[allocate] trying to allocate a primary shard " + shardId + "], which is disabled");
}
RoutingNode routingNode = allocation.routingNodes().node(discoNode.id());
Decision decision = allocation.deciders().canAllocate(shardRouting, routingNode, allocation);
if (decision.type() == Decision.Type.NO) {
throw new ElasticSearchIllegalArgumentException("[allocate] allocation of " + shardId + " on node " + discoNode + " is not allowed, reason: " + decision);
}
// go over and remove it from the unassigned
for (Iterator it = allocation.routingNodes().unassigned().iterator(); it.hasNext(); ) {
if (it.next() != shardRouting) {
continue;
}
it.remove();
routingNode.add(shardRouting);
if (shardRouting.primary()) {
// we need to clear the post allocation flag, since its an explicit allocation of the primary shard
// and we want to force allocate it (and create a new index for it)
allocation.routingNodes().addClearPostAllocationFlag(shardRouting.shardId());
}
break;
}
}
}