/*
* 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.routing;
import org.elasticsearch.cluster.node.DiscoveryNode;
import org.elasticsearch.cluster.node.DiscoveryNodes;
import org.elasticsearch.common.Randomness;
import org.elasticsearch.common.collect.MapBuilder;
import org.elasticsearch.common.io.stream.StreamInput;
import org.elasticsearch.common.io.stream.StreamOutput;
import org.elasticsearch.common.util.set.Sets;
import org.elasticsearch.index.Index;
import org.elasticsearch.index.shard.ShardId;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashSet;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import java.util.Set;
import static java.util.Collections.emptyMap;
/**
* {@link IndexShardRoutingTable} encapsulates all instances of a single shard.
* Each Elasticsearch index consists of multiple shards, each shard encapsulates
* a disjoint set of the index data and each shard has one or more instances
* referred to as replicas of a shard. Given that, this class encapsulates all
* replicas (instances) for a single index shard.
*/
public class IndexShardRoutingTable implements Iterable<ShardRouting> {
final ShardShuffler shuffler;
final ShardId shardId;
final ShardRouting primary;
final List<ShardRouting> primaryAsList;
final List<ShardRouting> replicas;
final List<ShardRouting> shards;
final List<ShardRouting> activeShards;
final List<ShardRouting> assignedShards;
static final List<ShardRouting> NO_SHARDS = Collections.emptyList();
final boolean allShardsStarted;
private volatile Map<AttributesKey, AttributesRoutings> activeShardsByAttributes = emptyMap();
private volatile Map<AttributesKey, AttributesRoutings> initializingShardsByAttributes = emptyMap();
private final Object shardsByAttributeMutex = new Object();
/**
* The initializing list, including ones that are initializing on a target node because of relocation.
* If we can come up with a better variable name, it would be nice...
*/
final List<ShardRouting> allInitializingShards;
IndexShardRoutingTable(ShardId shardId, List<ShardRouting> shards) {
this.shardId = shardId;
this.shuffler = new RotationShardShuffler(Randomness.get().nextInt());
this.shards = Collections.unmodifiableList(shards);
ShardRouting primary = null;
List<ShardRouting> replicas = new ArrayList<>();
List<ShardRouting> activeShards = new ArrayList<>();
List<ShardRouting> assignedShards = new ArrayList<>();
List<ShardRouting> allInitializingShards = new ArrayList<>();
boolean allShardsStarted = true;
for (ShardRouting shard : shards) {
if (shard.primary()) {
primary = shard;
} else {
replicas.add(shard);
}
if (shard.active()) {
activeShards.add(shard);
}
if (shard.initializing()) {
allInitializingShards.add(shard);
}
if (shard.relocating()) {
// create the target initializing shard routing on the node the shard is relocating to
allInitializingShards.add(shard.getTargetRelocatingShard());
}
if (shard.assignedToNode()) {
assignedShards.add(shard);
}
if (shard.state() != ShardRoutingState.STARTED) {
allShardsStarted = false;
}
}
this.allShardsStarted = allShardsStarted;
this.primary = primary;
if (primary != null) {
this.primaryAsList = Collections.singletonList(primary);
} else {
this.primaryAsList = Collections.emptyList();
}
this.replicas = Collections.unmodifiableList(replicas);
this.activeShards = Collections.unmodifiableList(activeShards);
this.assignedShards = Collections.unmodifiableList(assignedShards);
this.allInitializingShards = Collections.unmodifiableList(allInitializingShards);
}
/**
* Returns the shards id
*
* @return id of the shard
*/
public ShardId shardId() {
return shardId;
}
/**
* Returns the shards id
*
* @return id of the shard
*/
public ShardId getShardId() {
return shardId();
}
@Override
public Iterator<ShardRouting> iterator() {
return shards.iterator();
}
/**
* Returns the number of this shards instances.
*/
public int size() {
return shards.size();
}
/**
* Returns the number of this shards instances.
*/
public int getSize() {
return size();
}
/**
* Returns a {@link List} of shards
*
* @return a {@link List} of shards
*/
public List<ShardRouting> shards() {
return this.shards;
}
/**
* Returns a {@link List} of shards
*
* @return a {@link List} of shards
*/
public List<ShardRouting> getShards() {
return shards();
}
/**
* Returns a {@link List} of active shards
*
* @return a {@link List} of shards
*/
public List<ShardRouting> activeShards() {
return this.activeShards;
}
/**
* Returns a {@link List} of all initializing shards, including target shards of relocations
*
* @return a {@link List} of shards
*/
public List<ShardRouting> getAllInitializingShards() {
return this.allInitializingShards;
}
/**
* Returns a {@link List} of active shards
*
* @return a {@link List} of shards
*/
public List<ShardRouting> getActiveShards() {
return activeShards();
}
/**
* Returns a {@link List} of assigned shards
*
* @return a {@link List} of shards
*/
public List<ShardRouting> assignedShards() {
return this.assignedShards;
}
/**
* Returns a {@link List} of assigned shards
*
* @return a {@link List} of shards
*/
public List<ShardRouting> getAssignedShards() {
return this.assignedShards;
}
public ShardIterator shardsRandomIt() {
return new PlainShardIterator(shardId, shuffler.shuffle(shards));
}
public ShardIterator shardsIt() {
return new PlainShardIterator(shardId, shards);
}
public ShardIterator shardsIt(int seed) {
return new PlainShardIterator(shardId, shuffler.shuffle(shards, seed));
}
/**
* Returns an iterator over active and initializing shards. Making sure though that
* its random within the active shards, and initializing shards are the last to iterate through.
*/
public ShardIterator activeInitializingShardsRandomIt() {
return activeInitializingShardsIt(shuffler.nextSeed());
}
/**
* Returns an iterator over active and initializing shards. Making sure though that
* its random within the active shards, and initializing shards are the last to iterate through.
*/
public ShardIterator activeInitializingShardsIt(int seed) {
if (allInitializingShards.isEmpty()) {
return new PlainShardIterator(shardId, shuffler.shuffle(activeShards, seed));
}
ArrayList<ShardRouting> ordered = new ArrayList<>(activeShards.size() + allInitializingShards.size());
ordered.addAll(shuffler.shuffle(activeShards, seed));
ordered.addAll(allInitializingShards);
return new PlainShardIterator(shardId, ordered);
}
/**
* Returns true if no primaries are active or initializing for this shard
*/
private boolean noPrimariesActive() {
if (!primaryAsList.isEmpty() && !primaryAsList.get(0).active() && !primaryAsList.get(0).initializing()) {
return true;
}
return false;
}
/**
* Returns an iterator only on the primary shard.
*/
public ShardIterator primaryShardIt() {
return new PlainShardIterator(shardId, primaryAsList);
}
public ShardIterator primaryActiveInitializingShardIt() {
if (noPrimariesActive()) {
return new PlainShardIterator(shardId, NO_SHARDS);
}
return primaryShardIt();
}
public ShardIterator primaryFirstActiveInitializingShardsIt() {
ArrayList<ShardRouting> ordered = new ArrayList<>(activeShards.size() + allInitializingShards.size());
// fill it in a randomized fashion
for (ShardRouting shardRouting : shuffler.shuffle(activeShards)) {
ordered.add(shardRouting);
if (shardRouting.primary()) {
// switch, its the matching node id
ordered.set(ordered.size() - 1, ordered.get(0));
ordered.set(0, shardRouting);
}
}
// no need to worry about primary first here..., its temporal
if (!allInitializingShards.isEmpty()) {
ordered.addAll(allInitializingShards);
}
return new PlainShardIterator(shardId, ordered);
}
public ShardIterator replicaActiveInitializingShardIt() {
// If the primaries are unassigned, return an empty list (there aren't
// any replicas to query anyway)
if (noPrimariesActive()) {
return new PlainShardIterator(shardId, NO_SHARDS);
}
LinkedList<ShardRouting> ordered = new LinkedList<>();
for (ShardRouting replica : shuffler.shuffle(replicas)) {
if (replica.active()) {
ordered.addFirst(replica);
} else if (replica.initializing()) {
ordered.addLast(replica);
}
}
return new PlainShardIterator(shardId, ordered);
}
public ShardIterator replicaFirstActiveInitializingShardsIt() {
// If the primaries are unassigned, return an empty list (there aren't
// any replicas to query anyway)
if (noPrimariesActive()) {
return new PlainShardIterator(shardId, NO_SHARDS);
}
ArrayList<ShardRouting> ordered = new ArrayList<>(activeShards.size() + allInitializingShards.size());
// fill it in a randomized fashion with the active replicas
for (ShardRouting replica : shuffler.shuffle(replicas)) {
if (replica.active()) {
ordered.add(replica);
}
}
// Add the primary shard
ordered.add(primary);
// Add initializing shards last
if (!allInitializingShards.isEmpty()) {
ordered.addAll(allInitializingShards);
}
return new PlainShardIterator(shardId, ordered);
}
public ShardIterator onlyNodeActiveInitializingShardsIt(String nodeId) {
ArrayList<ShardRouting> ordered = new ArrayList<>(activeShards.size() + allInitializingShards.size());
int seed = shuffler.nextSeed();
for (ShardRouting shardRouting : shuffler.shuffle(activeShards, seed)) {
if (nodeId.equals(shardRouting.currentNodeId())) {
ordered.add(shardRouting);
}
}
for (ShardRouting shardRouting : shuffler.shuffle(allInitializingShards, seed)) {
if (nodeId.equals(shardRouting.currentNodeId())) {
ordered.add(shardRouting);
}
}
return new PlainShardIterator(shardId, ordered);
}
public ShardIterator onlyNodeSelectorActiveInitializingShardsIt(String nodeAttributes, DiscoveryNodes discoveryNodes) {
return onlyNodeSelectorActiveInitializingShardsIt(new String[] {nodeAttributes}, discoveryNodes);
}
/**
* Returns shards based on nodeAttributes given such as node name , node attribute, node IP
* Supports node specifications in cluster API
*/
public ShardIterator onlyNodeSelectorActiveInitializingShardsIt(String[] nodeAttributes, DiscoveryNodes discoveryNodes) {
ArrayList<ShardRouting> ordered = new ArrayList<>(activeShards.size() + allInitializingShards.size());
Set<String> selectedNodes = Sets.newHashSet(discoveryNodes.resolveNodes(nodeAttributes));
int seed = shuffler.nextSeed();
for (ShardRouting shardRouting : shuffler.shuffle(activeShards, seed)) {
if (selectedNodes.contains(shardRouting.currentNodeId())) {
ordered.add(shardRouting);
}
}
for (ShardRouting shardRouting : shuffler.shuffle(allInitializingShards, seed)) {
if (selectedNodes.contains(shardRouting.currentNodeId())) {
ordered.add(shardRouting);
}
}
if (ordered.isEmpty()) {
final String message = String.format(
Locale.ROOT,
"no data nodes with %s [%s] found for shard: %s",
nodeAttributes.length == 1 ? "criteria" : "criterion",
String.join(",", nodeAttributes),
shardId());
throw new IllegalArgumentException(message);
}
return new PlainShardIterator(shardId, ordered);
}
public ShardIterator preferNodeActiveInitializingShardsIt(Set<String> nodeIds) {
ArrayList<ShardRouting> preferred = new ArrayList<>(activeShards.size() + allInitializingShards.size());
ArrayList<ShardRouting> notPreferred = new ArrayList<>(activeShards.size() + allInitializingShards.size());
// fill it in a randomized fashion
for (ShardRouting shardRouting : shuffler.shuffle(activeShards)) {
if (nodeIds.contains(shardRouting.currentNodeId())) {
preferred.add(shardRouting);
} else {
notPreferred.add(shardRouting);
}
}
preferred.addAll(notPreferred);
if (!allInitializingShards.isEmpty()) {
preferred.addAll(allInitializingShards);
}
return new PlainShardIterator(shardId, preferred);
}
@Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
IndexShardRoutingTable that = (IndexShardRoutingTable) o;
if (!shardId.equals(that.shardId)) return false;
if (!shards.equals(that.shards)) return false;
return true;
}
@Override
public int hashCode() {
int result = shardId.hashCode();
result = 31 * result + shards.hashCode();
return result;
}
/**
* Returns <code>true</code> iff all shards in the routing table are started otherwise <code>false</code>
*/
public boolean allShardsStarted() {
return allShardsStarted;
}
static class AttributesKey {
final String[] attributes;
AttributesKey(String[] attributes) {
this.attributes = attributes;
}
@Override
public int hashCode() {
return Arrays.hashCode(attributes);
}
@Override
public boolean equals(Object obj) {
return Arrays.equals(attributes, ((AttributesKey) obj).attributes);
}
}
static class AttributesRoutings {
public final List<ShardRouting> withSameAttribute;
public final List<ShardRouting> withoutSameAttribute;
public final int totalSize;
AttributesRoutings(List<ShardRouting> withSameAttribute, List<ShardRouting> withoutSameAttribute) {
this.withSameAttribute = withSameAttribute;
this.withoutSameAttribute = withoutSameAttribute;
this.totalSize = withoutSameAttribute.size() + withSameAttribute.size();
}
}
private AttributesRoutings getActiveAttribute(AttributesKey key, DiscoveryNodes nodes) {
AttributesRoutings shardRoutings = activeShardsByAttributes.get(key);
if (shardRoutings == null) {
synchronized (shardsByAttributeMutex) {
ArrayList<ShardRouting> from = new ArrayList<>(activeShards);
List<ShardRouting> to = collectAttributeShards(key, nodes, from);
shardRoutings = new AttributesRoutings(to, Collections.unmodifiableList(from));
activeShardsByAttributes = MapBuilder.newMapBuilder(activeShardsByAttributes).put(key, shardRoutings).immutableMap();
}
}
return shardRoutings;
}
private AttributesRoutings getInitializingAttribute(AttributesKey key, DiscoveryNodes nodes) {
AttributesRoutings shardRoutings = initializingShardsByAttributes.get(key);
if (shardRoutings == null) {
synchronized (shardsByAttributeMutex) {
ArrayList<ShardRouting> from = new ArrayList<>(allInitializingShards);
List<ShardRouting> to = collectAttributeShards(key, nodes, from);
shardRoutings = new AttributesRoutings(to, Collections.unmodifiableList(from));
initializingShardsByAttributes = MapBuilder.newMapBuilder(initializingShardsByAttributes).put(key, shardRoutings).immutableMap();
}
}
return shardRoutings;
}
private static List<ShardRouting> collectAttributeShards(AttributesKey key, DiscoveryNodes nodes, ArrayList<ShardRouting> from) {
final ArrayList<ShardRouting> to = new ArrayList<>();
for (final String attribute : key.attributes) {
final String localAttributeValue = nodes.getLocalNode().getAttributes().get(attribute);
if (localAttributeValue != null) {
for (Iterator<ShardRouting> iterator = from.iterator(); iterator.hasNext(); ) {
ShardRouting fromShard = iterator.next();
final DiscoveryNode discoveryNode = nodes.get(fromShard.currentNodeId());
if (discoveryNode == null) {
iterator.remove(); // node is not present anymore - ignore shard
} else if (localAttributeValue.equals(discoveryNode.getAttributes().get(attribute))) {
iterator.remove();
to.add(fromShard);
}
}
}
}
return Collections.unmodifiableList(to);
}
public ShardIterator preferAttributesActiveInitializingShardsIt(String[] attributes, DiscoveryNodes nodes) {
return preferAttributesActiveInitializingShardsIt(attributes, nodes, shuffler.nextSeed());
}
public ShardIterator preferAttributesActiveInitializingShardsIt(String[] attributes, DiscoveryNodes nodes, int seed) {
AttributesKey key = new AttributesKey(attributes);
AttributesRoutings activeRoutings = getActiveAttribute(key, nodes);
AttributesRoutings initializingRoutings = getInitializingAttribute(key, nodes);
// we now randomize, once between the ones that have the same attributes, and once for the ones that don't
// we don't want to mix between the two!
ArrayList<ShardRouting> ordered = new ArrayList<>(activeRoutings.totalSize + initializingRoutings.totalSize);
ordered.addAll(shuffler.shuffle(activeRoutings.withSameAttribute, seed));
ordered.addAll(shuffler.shuffle(activeRoutings.withoutSameAttribute, seed));
ordered.addAll(shuffler.shuffle(initializingRoutings.withSameAttribute, seed));
ordered.addAll(shuffler.shuffle(initializingRoutings.withoutSameAttribute, seed));
return new PlainShardIterator(shardId, ordered);
}
public ShardRouting primaryShard() {
return primary;
}
public List<ShardRouting> replicaShards() {
return this.replicas;
}
public List<ShardRouting> replicaShardsWithState(ShardRoutingState... states) {
List<ShardRouting> shards = new ArrayList<>();
for (ShardRouting shardEntry : replicas) {
for (ShardRoutingState state : states) {
if (shardEntry.state() == state) {
shards.add(shardEntry);
}
}
}
return shards;
}
public List<ShardRouting> shardsWithState(ShardRoutingState state) {
if (state == ShardRoutingState.INITIALIZING) {
return allInitializingShards;
}
List<ShardRouting> shards = new ArrayList<>();
for (ShardRouting shardEntry : this) {
if (shardEntry.state() == state) {
shards.add(shardEntry);
}
}
return shards;
}
public static class Builder {
private ShardId shardId;
private final List<ShardRouting> shards;
public Builder(IndexShardRoutingTable indexShard) {
this.shardId = indexShard.shardId;
this.shards = new ArrayList<>(indexShard.shards);
}
public Builder(ShardId shardId) {
this.shardId = shardId;
this.shards = new ArrayList<>();
}
public Builder addShard(ShardRouting shardEntry) {
shards.add(shardEntry);
return this;
}
public Builder removeShard(ShardRouting shardEntry) {
shards.remove(shardEntry);
return this;
}
public IndexShardRoutingTable build() {
// don't allow more than one shard copy with same id to be allocated to same node
assert distinctNodes(shards) : "more than one shard with same id assigned to same node (shards: " + shards + ")";
return new IndexShardRoutingTable(shardId, Collections.unmodifiableList(new ArrayList<>(shards)));
}
static boolean distinctNodes(List<ShardRouting> shards) {
Set<String> nodes = new HashSet<>();
for (ShardRouting shard : shards) {
if (shard.assignedToNode()) {
if (nodes.add(shard.currentNodeId()) == false) {
return false;
}
if (shard.relocating()) {
if (nodes.add(shard.relocatingNodeId()) == false) {
return false;
}
}
}
}
return true;
}
public static IndexShardRoutingTable readFrom(StreamInput in) throws IOException {
Index index = new Index(in);
return readFromThin(in, index);
}
public static IndexShardRoutingTable readFromThin(StreamInput in, Index index) throws IOException {
int iShardId = in.readVInt();
ShardId shardId = new ShardId(index, iShardId);
Builder builder = new Builder(shardId);
int size = in.readVInt();
for (int i = 0; i < size; i++) {
ShardRouting shard = new ShardRouting(shardId, in);
builder.addShard(shard);
}
return builder.build();
}
public static void writeTo(IndexShardRoutingTable indexShard, StreamOutput out) throws IOException {
out.writeString(indexShard.shardId().getIndex().getName());
writeToThin(indexShard, out);
}
public static void writeToThin(IndexShardRoutingTable indexShard, StreamOutput out) throws IOException {
out.writeVInt(indexShard.shardId.id());
out.writeVInt(indexShard.shards.size());
for (ShardRouting entry : indexShard) {
entry.writeToThin(out);
}
}
}
}