/*
* 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.cluster;
import com.carrotsearch.hppc.cursors.IntObjectCursor;
import com.carrotsearch.hppc.cursors.ObjectCursor;
import com.carrotsearch.hppc.cursors.ObjectObjectCursor;
import org.elasticsearch.cluster.block.ClusterBlock;
import org.elasticsearch.cluster.block.ClusterBlocks;
import org.elasticsearch.cluster.metadata.IndexMetaData;
import org.elasticsearch.cluster.metadata.IndexTemplateMetaData;
import org.elasticsearch.cluster.metadata.MappingMetaData;
import org.elasticsearch.cluster.metadata.MetaData;
import org.elasticsearch.cluster.node.DiscoveryNode;
import org.elasticsearch.cluster.node.DiscoveryNodes;
import org.elasticsearch.cluster.routing.IndexRoutingTable;
import org.elasticsearch.cluster.routing.IndexShardRoutingTable;
import org.elasticsearch.cluster.routing.RoutingNode;
import org.elasticsearch.cluster.routing.RoutingNodes;
import org.elasticsearch.cluster.routing.RoutingTable;
import org.elasticsearch.cluster.routing.ShardRouting;
import org.elasticsearch.cluster.service.ClusterService;
import org.elasticsearch.common.Strings;
import org.elasticsearch.common.UUIDs;
import org.elasticsearch.common.bytes.BytesArray;
import org.elasticsearch.common.bytes.BytesReference;
import org.elasticsearch.common.collect.ImmutableOpenMap;
import org.elasticsearch.common.compress.CompressedXContent;
import org.elasticsearch.common.io.stream.BytesStreamOutput;
import org.elasticsearch.common.io.stream.NamedWriteableAwareStreamInput;
import org.elasticsearch.common.io.stream.NamedWriteableRegistry;
import org.elasticsearch.common.io.stream.StreamInput;
import org.elasticsearch.common.io.stream.StreamOutput;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.common.xcontent.ToXContent;
import org.elasticsearch.common.xcontent.XContentBuilder;
import org.elasticsearch.common.xcontent.XContentHelper;
import org.elasticsearch.discovery.Discovery;
import org.elasticsearch.discovery.zen.PublishClusterStateAction;
import java.io.IOException;
import java.util.EnumSet;
import java.util.HashMap;
import java.util.Locale;
import java.util.Map;
import java.util.Set;
/**
* Represents the current state of the cluster.
* <p>
* The cluster state object is immutable with the exception of the {@link RoutingNodes} structure, which is
* built on demand from the {@link RoutingTable}.
* The cluster state can be updated only on the master node. All updates are performed by on a
* single thread and controlled by the {@link ClusterService}. After every update the
* {@link Discovery#publish} method publishes a new version of the cluster state to all other nodes in the
* cluster. The actual publishing mechanism is delegated to the {@link Discovery#publish} method and depends on
* the type of discovery. In the Zen Discovery it is handled in the {@link PublishClusterStateAction#publish} method. The
* publishing mechanism can be overridden by other discovery.
* <p>
* The cluster state implements the {@link Diffable} interface in order to support publishing of cluster state
* differences instead of the entire state on each change. The publishing mechanism should only send differences
* to a node if this node was present in the previous version of the cluster state. If a node was
* not present in the previous version of the cluster state, this node is unlikely to have the previous cluster
* state version and should be sent a complete version. In order to make sure that the differences are applied to the
* correct version of the cluster state, each cluster state version update generates {@link #stateUUID} that uniquely
* identifies this version of the state. This uuid is verified by the {@link ClusterStateDiff#apply} method to
* make sure that the correct diffs are applied. If uuids don’t match, the {@link ClusterStateDiff#apply} method
* throws the {@link IncompatibleClusterStateVersionException}, which causes the publishing mechanism to send
* a full version of the cluster state to the node on which this exception was thrown.
*/
public class ClusterState implements ToXContent, Diffable<ClusterState> {
public static final ClusterState EMPTY_STATE = builder(ClusterName.CLUSTER_NAME_SETTING.getDefault(Settings.EMPTY)).build();
public interface Custom extends NamedDiffable<Custom>, ToXContent {
}
private static final NamedDiffableValueSerializer<Custom> CUSTOM_VALUE_SERIALIZER = new NamedDiffableValueSerializer<>(Custom.class);
public static final String UNKNOWN_UUID = "_na_";
public static final long UNKNOWN_VERSION = -1;
private final long version;
private final String stateUUID;
private final RoutingTable routingTable;
private final DiscoveryNodes nodes;
private final MetaData metaData;
private final ClusterBlocks blocks;
private final ImmutableOpenMap<String, Custom> customs;
private final ClusterName clusterName;
private final boolean wasReadFromDiff;
// built on demand
private volatile RoutingNodes routingNodes;
public ClusterState(long version, String stateUUID, ClusterState state) {
this(state.clusterName, version, stateUUID, state.metaData(), state.routingTable(), state.nodes(), state.blocks(), state.customs(),
false);
}
public ClusterState(ClusterName clusterName, long version, String stateUUID, MetaData metaData, RoutingTable routingTable,
DiscoveryNodes nodes, ClusterBlocks blocks, ImmutableOpenMap<String, Custom> customs, boolean wasReadFromDiff) {
this.version = version;
this.stateUUID = stateUUID;
this.clusterName = clusterName;
this.metaData = metaData;
this.routingTable = routingTable;
this.nodes = nodes;
this.blocks = blocks;
this.customs = customs;
this.wasReadFromDiff = wasReadFromDiff;
}
public long version() {
return this.version;
}
public long getVersion() {
return version();
}
/**
* This stateUUID is automatically generated for for each version of cluster state. It is used to make sure that
* we are applying diffs to the right previous state.
*/
public String stateUUID() {
return this.stateUUID;
}
public DiscoveryNodes nodes() {
return this.nodes;
}
public DiscoveryNodes getNodes() {
return nodes();
}
public MetaData metaData() {
return this.metaData;
}
public MetaData getMetaData() {
return metaData();
}
public RoutingTable routingTable() {
return routingTable;
}
public RoutingTable getRoutingTable() {
return routingTable();
}
public ClusterBlocks blocks() {
return this.blocks;
}
public ClusterBlocks getBlocks() {
return blocks;
}
public ImmutableOpenMap<String, Custom> customs() {
return this.customs;
}
public ImmutableOpenMap<String, Custom> getCustoms() {
return this.customs;
}
public <T extends Custom> T custom(String type) {
return (T) customs.get(type);
}
public ClusterName getClusterName() {
return this.clusterName;
}
// Used for testing and logging to determine how this cluster state was send over the wire
public boolean wasReadFromDiff() {
return wasReadFromDiff;
}
/**
* Returns a built (on demand) routing nodes view of the routing table.
*/
public RoutingNodes getRoutingNodes() {
if (routingNodes != null) {
return routingNodes;
}
routingNodes = new RoutingNodes(this);
return routingNodes;
}
@Override
public String toString() {
StringBuilder sb = new StringBuilder();
sb.append("cluster uuid: ").append(metaData.clusterUUID()).append("\n");
sb.append("version: ").append(version).append("\n");
sb.append("state uuid: ").append(stateUUID).append("\n");
sb.append("from_diff: ").append(wasReadFromDiff).append("\n");
sb.append("meta data version: ").append(metaData.version()).append("\n");
final String TAB = " ";
for (IndexMetaData indexMetaData : metaData) {
sb.append(TAB).append(indexMetaData.getIndex());
sb.append(": v[").append(indexMetaData.getVersion()).append("]\n");
for (int shard = 0; shard < indexMetaData.getNumberOfShards(); shard++) {
sb.append(TAB).append(TAB).append(shard).append(": ");
sb.append("p_term [").append(indexMetaData.primaryTerm(shard)).append("], ");
sb.append("isa_ids ").append(indexMetaData.inSyncAllocationIds(shard)).append("\n");
}
}
sb.append(blocks());
sb.append(nodes());
sb.append(routingTable());
sb.append(getRoutingNodes());
if (customs.isEmpty() == false) {
sb.append("customs:\n");
for (ObjectObjectCursor<String, Custom> cursor : customs) {
final String type = cursor.key;
final Custom custom = cursor.value;
sb.append(TAB).append(type).append(": ").append(custom);
}
}
return sb.toString();
}
/**
* a cluster state supersedes another state if they are from the same master and the version of this state is higher than that of the
* other state.
* <p>
* In essence that means that all the changes from the other cluster state are also reflected by the current one
*/
public boolean supersedes(ClusterState other) {
return this.nodes().getMasterNodeId() != null && this.nodes().getMasterNodeId().equals(other.nodes().getMasterNodeId())
&& this.version() > other.version();
}
public enum Metric {
VERSION("version"),
MASTER_NODE("master_node"),
BLOCKS("blocks"),
NODES("nodes"),
METADATA("metadata"),
ROUTING_TABLE("routing_table"),
ROUTING_NODES("routing_nodes"),
CUSTOMS("customs");
private static Map<String, Metric> valueToEnum;
static {
valueToEnum = new HashMap<>();
for (Metric metric : Metric.values()) {
valueToEnum.put(metric.value, metric);
}
}
private final String value;
Metric(String value) {
this.value = value;
}
public static EnumSet<Metric> parseString(String param, boolean ignoreUnknown) {
String[] metrics = Strings.splitStringByCommaToArray(param);
EnumSet<Metric> result = EnumSet.noneOf(Metric.class);
for (String metric : metrics) {
if ("_all".equals(metric)) {
result = EnumSet.allOf(Metric.class);
break;
}
Metric m = valueToEnum.get(metric);
if (m == null) {
if (!ignoreUnknown) {
throw new IllegalArgumentException("Unknown metric [" + metric + "]");
}
} else {
result.add(m);
}
}
return result;
}
@Override
public String toString() {
return value;
}
}
@Override
public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
EnumSet<Metric> metrics = Metric.parseString(params.param("metric", "_all"), true);
if (metrics.contains(Metric.VERSION)) {
builder.field("version", version);
builder.field("state_uuid", stateUUID);
}
if (metrics.contains(Metric.MASTER_NODE)) {
builder.field("master_node", nodes().getMasterNodeId());
}
if (metrics.contains(Metric.BLOCKS)) {
builder.startObject("blocks");
if (!blocks().global().isEmpty()) {
builder.startObject("global");
for (ClusterBlock block : blocks().global()) {
block.toXContent(builder, params);
}
builder.endObject();
}
if (!blocks().indices().isEmpty()) {
builder.startObject("indices");
for (ObjectObjectCursor<String, Set<ClusterBlock>> entry : blocks().indices()) {
builder.startObject(entry.key);
for (ClusterBlock block : entry.value) {
block.toXContent(builder, params);
}
builder.endObject();
}
builder.endObject();
}
builder.endObject();
}
// nodes
if (metrics.contains(Metric.NODES)) {
builder.startObject("nodes");
for (DiscoveryNode node : nodes) {
node.toXContent(builder, params);
}
builder.endObject();
}
// meta data
if (metrics.contains(Metric.METADATA)) {
builder.startObject("metadata");
builder.field("cluster_uuid", metaData().clusterUUID());
builder.startObject("templates");
for (ObjectCursor<IndexTemplateMetaData> cursor : metaData().templates().values()) {
IndexTemplateMetaData templateMetaData = cursor.value;
builder.startObject(templateMetaData.name());
builder.field("index_patterns", templateMetaData.patterns());
builder.field("order", templateMetaData.order());
builder.startObject("settings");
Settings settings = templateMetaData.settings();
settings.toXContent(builder, params);
builder.endObject();
builder.startObject("mappings");
for (ObjectObjectCursor<String, CompressedXContent> cursor1 : templateMetaData.mappings()) {
Map<String, Object> mapping = XContentHelper.convertToMap(new BytesArray(cursor1.value.uncompressed()), false).v2();
if (mapping.size() == 1 && mapping.containsKey(cursor1.key)) {
// the type name is the root value, reduce it
mapping = (Map<String, Object>) mapping.get(cursor1.key);
}
builder.field(cursor1.key);
builder.map(mapping);
}
builder.endObject();
builder.endObject();
}
builder.endObject();
builder.startObject("indices");
for (IndexMetaData indexMetaData : metaData()) {
builder.startObject(indexMetaData.getIndex().getName());
builder.field("state", indexMetaData.getState().toString().toLowerCase(Locale.ENGLISH));
builder.startObject("settings");
Settings settings = indexMetaData.getSettings();
settings.toXContent(builder, params);
builder.endObject();
builder.startObject("mappings");
for (ObjectObjectCursor<String, MappingMetaData> cursor : indexMetaData.getMappings()) {
Map<String, Object> mapping = XContentHelper
.convertToMap(new BytesArray(cursor.value.source().uncompressed()), false).v2();
if (mapping.size() == 1 && mapping.containsKey(cursor.key)) {
// the type name is the root value, reduce it
mapping = (Map<String, Object>) mapping.get(cursor.key);
}
builder.field(cursor.key);
builder.map(mapping);
}
builder.endObject();
builder.startArray("aliases");
for (ObjectCursor<String> cursor : indexMetaData.getAliases().keys()) {
builder.value(cursor.value);
}
builder.endArray();
builder.startObject(IndexMetaData.KEY_PRIMARY_TERMS);
for (int shard = 0; shard < indexMetaData.getNumberOfShards(); shard++) {
builder.field(Integer.toString(shard), indexMetaData.primaryTerm(shard));
}
builder.endObject();
builder.startObject(IndexMetaData.KEY_IN_SYNC_ALLOCATIONS);
for (IntObjectCursor<Set<String>> cursor : indexMetaData.getInSyncAllocationIds()) {
builder.startArray(String.valueOf(cursor.key));
for (String allocationId : cursor.value) {
builder.value(allocationId);
}
builder.endArray();
}
builder.endObject();
// index metadata
builder.endObject();
}
builder.endObject();
for (ObjectObjectCursor<String, MetaData.Custom> cursor : metaData.customs()) {
builder.startObject(cursor.key);
cursor.value.toXContent(builder, params);
builder.endObject();
}
builder.endObject();
}
// routing table
if (metrics.contains(Metric.ROUTING_TABLE)) {
builder.startObject("routing_table");
builder.startObject("indices");
for (IndexRoutingTable indexRoutingTable : routingTable()) {
builder.startObject(indexRoutingTable.getIndex().getName());
builder.startObject("shards");
for (IndexShardRoutingTable indexShardRoutingTable : indexRoutingTable) {
builder.startArray(Integer.toString(indexShardRoutingTable.shardId().id()));
for (ShardRouting shardRouting : indexShardRoutingTable) {
shardRouting.toXContent(builder, params);
}
builder.endArray();
}
builder.endObject();
builder.endObject();
}
builder.endObject();
builder.endObject();
}
// routing nodes
if (metrics.contains(Metric.ROUTING_NODES)) {
builder.startObject("routing_nodes");
builder.startArray("unassigned");
for (ShardRouting shardRouting : getRoutingNodes().unassigned()) {
shardRouting.toXContent(builder, params);
}
builder.endArray();
builder.startObject("nodes");
for (RoutingNode routingNode : getRoutingNodes()) {
builder.startArray(routingNode.nodeId() == null ? "null" : routingNode.nodeId());
for (ShardRouting shardRouting : routingNode) {
shardRouting.toXContent(builder, params);
}
builder.endArray();
}
builder.endObject();
builder.endObject();
}
if (metrics.contains(Metric.CUSTOMS)) {
for (ObjectObjectCursor<String, Custom> cursor : customs) {
builder.startObject(cursor.key);
cursor.value.toXContent(builder, params);
builder.endObject();
}
}
return builder;
}
public static Builder builder(ClusterName clusterName) {
return new Builder(clusterName);
}
public static Builder builder(ClusterState state) {
return new Builder(state);
}
public static class Builder {
private final ClusterName clusterName;
private long version = 0;
private String uuid = UNKNOWN_UUID;
private MetaData metaData = MetaData.EMPTY_META_DATA;
private RoutingTable routingTable = RoutingTable.EMPTY_ROUTING_TABLE;
private DiscoveryNodes nodes = DiscoveryNodes.EMPTY_NODES;
private ClusterBlocks blocks = ClusterBlocks.EMPTY_CLUSTER_BLOCK;
private final ImmutableOpenMap.Builder<String, Custom> customs;
private boolean fromDiff;
public Builder(ClusterState state) {
this.clusterName = state.clusterName;
this.version = state.version();
this.uuid = state.stateUUID();
this.nodes = state.nodes();
this.routingTable = state.routingTable();
this.metaData = state.metaData();
this.blocks = state.blocks();
this.customs = ImmutableOpenMap.builder(state.customs());
this.fromDiff = false;
}
public Builder(ClusterName clusterName) {
customs = ImmutableOpenMap.builder();
this.clusterName = clusterName;
}
public Builder nodes(DiscoveryNodes.Builder nodesBuilder) {
return nodes(nodesBuilder.build());
}
public Builder nodes(DiscoveryNodes nodes) {
this.nodes = nodes;
return this;
}
public DiscoveryNodes nodes() {
return nodes;
}
public Builder routingTable(RoutingTable routingTable) {
this.routingTable = routingTable;
return this;
}
public Builder metaData(MetaData.Builder metaDataBuilder) {
return metaData(metaDataBuilder.build());
}
public Builder metaData(MetaData metaData) {
this.metaData = metaData;
return this;
}
public Builder blocks(ClusterBlocks.Builder blocksBuilder) {
return blocks(blocksBuilder.build());
}
public Builder blocks(ClusterBlocks blocks) {
this.blocks = blocks;
return this;
}
public Builder version(long version) {
this.version = version;
return this;
}
public Builder incrementVersion() {
this.version = version + 1;
this.uuid = UNKNOWN_UUID;
return this;
}
public Builder stateUUID(String uuid) {
this.uuid = uuid;
return this;
}
public Builder putCustom(String type, Custom custom) {
customs.put(type, custom);
return this;
}
public Builder removeCustom(String type) {
customs.remove(type);
return this;
}
public Builder customs(ImmutableOpenMap<String, Custom> customs) {
this.customs.putAll(customs);
return this;
}
public Builder fromDiff(boolean fromDiff) {
this.fromDiff = fromDiff;
return this;
}
public ClusterState build() {
if (UNKNOWN_UUID.equals(uuid)) {
uuid = UUIDs.randomBase64UUID();
}
return new ClusterState(clusterName, version, uuid, metaData, routingTable, nodes, blocks, customs.build(), fromDiff);
}
public static byte[] toBytes(ClusterState state) throws IOException {
BytesStreamOutput os = new BytesStreamOutput();
state.writeTo(os);
return BytesReference.toBytes(os.bytes());
}
/**
* @param data input bytes
* @param localNode used to set the local node in the cluster state.
*/
public static ClusterState fromBytes(byte[] data, DiscoveryNode localNode, NamedWriteableRegistry registry) throws IOException {
StreamInput in = new NamedWriteableAwareStreamInput(StreamInput.wrap(data), registry);
return readFrom(in, localNode);
}
}
@Override
public Diff<ClusterState> diff(ClusterState previousState) {
return new ClusterStateDiff(previousState, this);
}
public static Diff<ClusterState> readDiffFrom(StreamInput in, DiscoveryNode localNode) throws IOException {
return new ClusterStateDiff(in, localNode);
}
public static ClusterState readFrom(StreamInput in, DiscoveryNode localNode) throws IOException {
ClusterName clusterName = new ClusterName(in);
Builder builder = new Builder(clusterName);
builder.version = in.readLong();
builder.uuid = in.readString();
builder.metaData = MetaData.readFrom(in);
builder.routingTable = RoutingTable.readFrom(in);
builder.nodes = DiscoveryNodes.readFrom(in, localNode);
builder.blocks = new ClusterBlocks(in);
int customSize = in.readVInt();
for (int i = 0; i < customSize; i++) {
Custom customIndexMetaData = in.readNamedWriteable(Custom.class);
builder.putCustom(customIndexMetaData.getWriteableName(), customIndexMetaData);
}
return builder.build();
}
@Override
public void writeTo(StreamOutput out) throws IOException {
clusterName.writeTo(out);
out.writeLong(version);
out.writeString(stateUUID);
metaData.writeTo(out);
routingTable.writeTo(out);
nodes.writeTo(out);
blocks.writeTo(out);
// filter out custom states not supported by the other node
int numberOfCustoms = 0;
for (ObjectCursor<Custom> cursor : customs.values()) {
if (out.getVersion().onOrAfter(cursor.value.getMinimalSupportedVersion())) {
numberOfCustoms++;
}
}
out.writeVInt(numberOfCustoms);
for (ObjectCursor<Custom> cursor : customs.values()) {
if (out.getVersion().onOrAfter(cursor.value.getMinimalSupportedVersion())) {
out.writeNamedWriteable(cursor.value);
}
}
}
private static class ClusterStateDiff implements Diff<ClusterState> {
private final long toVersion;
private final String fromUuid;
private final String toUuid;
private final ClusterName clusterName;
private final Diff<RoutingTable> routingTable;
private final Diff<DiscoveryNodes> nodes;
private final Diff<MetaData> metaData;
private final Diff<ClusterBlocks> blocks;
private final Diff<ImmutableOpenMap<String, Custom>> customs;
ClusterStateDiff(ClusterState before, ClusterState after) {
fromUuid = before.stateUUID;
toUuid = after.stateUUID;
toVersion = after.version;
clusterName = after.clusterName;
routingTable = after.routingTable.diff(before.routingTable);
nodes = after.nodes.diff(before.nodes);
metaData = after.metaData.diff(before.metaData);
blocks = after.blocks.diff(before.blocks);
customs = DiffableUtils.diff(before.customs, after.customs, DiffableUtils.getStringKeySerializer(), CUSTOM_VALUE_SERIALIZER);
}
ClusterStateDiff(StreamInput in, DiscoveryNode localNode) throws IOException {
clusterName = new ClusterName(in);
fromUuid = in.readString();
toUuid = in.readString();
toVersion = in.readLong();
routingTable = RoutingTable.readDiffFrom(in);
nodes = DiscoveryNodes.readDiffFrom(in, localNode);
metaData = MetaData.readDiffFrom(in);
blocks = ClusterBlocks.readDiffFrom(in);
customs = DiffableUtils.readImmutableOpenMapDiff(in, DiffableUtils.getStringKeySerializer(), CUSTOM_VALUE_SERIALIZER);
}
@Override
public void writeTo(StreamOutput out) throws IOException {
clusterName.writeTo(out);
out.writeString(fromUuid);
out.writeString(toUuid);
out.writeLong(toVersion);
routingTable.writeTo(out);
nodes.writeTo(out);
metaData.writeTo(out);
blocks.writeTo(out);
customs.writeTo(out);
}
@Override
public ClusterState apply(ClusterState state) {
Builder builder = new Builder(clusterName);
if (toUuid.equals(state.stateUUID)) {
// no need to read the rest - cluster state didn't change
return state;
}
if (fromUuid.equals(state.stateUUID) == false) {
throw new IncompatibleClusterStateVersionException(state.version, state.stateUUID, toVersion, fromUuid);
}
builder.stateUUID(toUuid);
builder.version(toVersion);
builder.routingTable(routingTable.apply(state.routingTable));
builder.nodes(nodes.apply(state.nodes));
builder.metaData(metaData.apply(state.metaData));
builder.blocks(blocks.apply(state.blocks));
builder.customs(customs.apply(state.customs));
builder.fromDiff(true);
return builder.build();
}
}
}