org.elasticsearch.transport.RemoteClusterService Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of elasticsearch Show documentation
Show all versions of elasticsearch Show documentation
Elasticsearch subproject :server
/*
* 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.transport;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.elasticsearch.Version;
import org.elasticsearch.action.ActionListener;
import org.elasticsearch.action.OriginalIndices;
import org.elasticsearch.action.support.GroupedActionListener;
import org.elasticsearch.action.support.IndicesOptions;
import org.elasticsearch.action.support.PlainActionFuture;
import org.elasticsearch.client.Client;
import org.elasticsearch.cluster.node.DiscoveryNode;
import org.elasticsearch.common.Strings;
import org.elasticsearch.common.settings.ClusterSettings;
import org.elasticsearch.common.settings.Setting;
import org.elasticsearch.common.settings.SettingUpgrader;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.common.unit.TimeValue;
import org.elasticsearch.common.util.concurrent.ConcurrentCollections;
import org.elasticsearch.common.util.concurrent.CountDown;
import org.elasticsearch.core.internal.io.IOUtils;
import org.elasticsearch.threadpool.ThreadPool;
import java.io.Closeable;
import java.io.IOException;
import java.util.Arrays;
import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
import java.util.function.BiFunction;
import java.util.function.Function;
import java.util.function.Predicate;
import java.util.stream.Stream;
import static org.elasticsearch.common.settings.Setting.boolSetting;
import static org.elasticsearch.common.settings.Setting.timeSetting;
/**
* Basic service for accessing remote clusters via gateway nodes
*/
public final class RemoteClusterService extends RemoteClusterAware implements Closeable {
private static final Logger logger = LogManager.getLogger(RemoteClusterService.class);
static {
// remove search.remote.* settings in 8.0.0
assert Version.CURRENT.major < 8;
}
public static final Setting SEARCH_REMOTE_INITIAL_CONNECTION_TIMEOUT_SETTING =
Setting.positiveTimeSetting(
"search.remote.initial_connect_timeout",
TimeValue.timeValueSeconds(30),
Setting.Property.NodeScope,
Setting.Property.Deprecated);
/**
* The initial connect timeout for remote cluster connections
*/
public static final Setting REMOTE_INITIAL_CONNECTION_TIMEOUT_SETTING =
Setting.positiveTimeSetting(
"cluster.remote.initial_connect_timeout",
SEARCH_REMOTE_INITIAL_CONNECTION_TIMEOUT_SETTING, // the default needs to be thirty seconds when fallback is removed
TimeValue.timeValueSeconds(30),
Setting.Property.NodeScope);
public static final Setting SEARCH_REMOTE_NODE_ATTRIBUTE =
Setting.simpleString("search.remote.node.attr", Setting.Property.NodeScope, Setting.Property.Deprecated);
/**
* The name of a node attribute to select nodes that should be connected to in the remote cluster.
* For instance a node can be configured with {@code node.attr.gateway: true} in order to be eligible as a gateway node between
* clusters. In that case {@code search.remote.node.attr: gateway} can be used to filter out other nodes in the remote cluster.
* The value of the setting is expected to be a boolean, {@code true} for nodes that can become gateways, {@code false} otherwise.
*/
public static final Setting REMOTE_NODE_ATTRIBUTE =
Setting.simpleString(
"cluster.remote.node.attr",
SEARCH_REMOTE_NODE_ATTRIBUTE, // no default is needed when fallback is removed, use simple string which gives empty
Setting.Property.NodeScope);
public static final Setting SEARCH_ENABLE_REMOTE_CLUSTERS =
Setting.boolSetting("search.remote.connect", true, Setting.Property.NodeScope, Setting.Property.Deprecated);
/**
* If true connecting to remote clusters is supported on this node. If false this node will not establish
* connections to any remote clusters configured. Search requests executed against this node (where this node is the coordinating node)
* will fail if remote cluster syntax is used as an index pattern. The default is true
*/
public static final Setting ENABLE_REMOTE_CLUSTERS =
Setting.boolSetting(
"cluster.remote.connect",
SEARCH_ENABLE_REMOTE_CLUSTERS, // the default needs to be true when fallback is removed
Setting.Property.NodeScope);
public static final Setting.AffixSetting SEARCH_REMOTE_CLUSTER_SKIP_UNAVAILABLE =
Setting.affixKeySetting(
"search.remote.",
"skip_unavailable",
key -> boolSetting(key, false, Setting.Property.Deprecated, Setting.Property.Dynamic, Setting.Property.NodeScope));
public static final SettingUpgrader SEARCH_REMOTE_CLUSTER_SKIP_UNAVAILABLE_UPGRADER = new SettingUpgrader() {
@Override
public Setting getSetting() {
return SEARCH_REMOTE_CLUSTER_SKIP_UNAVAILABLE;
}
@Override
public String getKey(final String key) {
return key.replaceFirst("^search", "cluster");
}
};
public static final Setting.AffixSetting REMOTE_CLUSTER_SKIP_UNAVAILABLE =
Setting.affixKeySetting(
"cluster.remote.",
"skip_unavailable",
(ns, key) -> boolSetting(
key,
// the default needs to be false when fallback is removed
"_na_".equals(key)
? SEARCH_REMOTE_CLUSTER_SKIP_UNAVAILABLE.getConcreteSettingForNamespace(key)
: SEARCH_REMOTE_CLUSTER_SKIP_UNAVAILABLE.getConcreteSetting(key.replaceAll("^cluster", "search")),
new RemoteConnectionEnabled<>(ns, key),
Setting.Property.Dynamic,
Setting.Property.NodeScope));
public static final Setting.AffixSetting REMOTE_CLUSTER_PING_SCHEDULE = Setting.affixKeySetting(
"cluster.remote.",
"transport.ping_schedule",
(ns, key) -> timeSetting(key, TransportSettings.PING_SCHEDULE, new RemoteConnectionEnabled<>(ns, key), Setting.Property.Dynamic,
Setting.Property.NodeScope));
public static final Setting.AffixSetting REMOTE_CLUSTER_COMPRESS = Setting.affixKeySetting(
"cluster.remote.",
"transport.compress",
(ns, key) -> boolSetting(key, TransportSettings.TRANSPORT_COMPRESS,
new RemoteConnectionEnabled<>(ns, key), Setting.Property.Dynamic, Setting.Property.NodeScope));
private final TransportService transportService;
private final Map remoteClusters = ConcurrentCollections.newConcurrentMap();
RemoteClusterService(Settings settings, TransportService transportService) {
super(settings);
this.transportService = transportService;
}
/**
* Returns true if at least one remote cluster is configured
*/
public boolean isCrossClusterSearchEnabled() {
return remoteClusters.isEmpty() == false;
}
boolean isRemoteNodeConnected(final String remoteCluster, final DiscoveryNode node) {
return remoteClusters.get(remoteCluster).isNodeConnected(node);
}
public Map groupIndices(IndicesOptions indicesOptions, String[] indices, Predicate indexExists) {
Map originalIndicesMap = new HashMap<>();
if (isCrossClusterSearchEnabled()) {
final Map> groupedIndices = groupClusterIndices(getRemoteClusterNames(), indices, indexExists);
if (groupedIndices.isEmpty()) {
//search on _all in the local cluster if neither local indices nor remote indices were specified
originalIndicesMap.put(LOCAL_CLUSTER_GROUP_KEY, new OriginalIndices(Strings.EMPTY_ARRAY, indicesOptions));
} else {
for (Map.Entry> entry : groupedIndices.entrySet()) {
String clusterAlias = entry.getKey();
List originalIndices = entry.getValue();
originalIndicesMap.put(clusterAlias,
new OriginalIndices(originalIndices.toArray(new String[0]), indicesOptions));
}
}
} else {
originalIndicesMap.put(LOCAL_CLUSTER_GROUP_KEY, new OriginalIndices(indices, indicesOptions));
}
return originalIndicesMap;
}
/**
* Returns true iff the given cluster is configured as a remote cluster. Otherwise false
*/
boolean isRemoteClusterRegistered(String clusterName) {
return remoteClusters.containsKey(clusterName);
}
/**
* Returns the registered remote cluster names.
*/
public Set getRegisteredRemoteClusterNames() {
// remoteClusters is unmodifiable so its key set will be unmodifiable too
return remoteClusters.keySet();
}
/**
* Returns a connection to the given node on the given remote cluster
*
* @throws IllegalArgumentException if the remote cluster is unknown
*/
public Transport.Connection getConnection(DiscoveryNode node, String cluster) {
return getRemoteClusterConnection(cluster).getConnection(node);
}
/**
* Ensures that the given cluster alias is connected. If the cluster is connected this operation
* will invoke the listener immediately.
*/
void ensureConnected(String clusterAlias, ActionListener listener) {
getRemoteClusterConnection(clusterAlias).ensureConnected(listener);
}
/**
* Returns whether the cluster identified by the provided alias is configured to be skipped when unavailable
*/
public boolean isSkipUnavailable(String clusterAlias) {
return getRemoteClusterConnection(clusterAlias).isSkipUnavailable();
}
public Transport.Connection getConnection(String cluster) {
return getRemoteClusterConnection(cluster).getConnection();
}
RemoteClusterConnection getRemoteClusterConnection(String cluster) {
RemoteClusterConnection connection = remoteClusters.get(cluster);
if (connection == null) {
throw new NoSuchRemoteClusterException(cluster);
}
return connection;
}
Set getRemoteClusterNames() {
return this.remoteClusters.keySet();
}
@Override
public void listenForUpdates(ClusterSettings clusterSettings) {
super.listenForUpdates(clusterSettings);
clusterSettings.addAffixUpdateConsumer(REMOTE_CLUSTER_SKIP_UNAVAILABLE, this::updateSkipUnavailable, (alias, value) -> {});
clusterSettings.addAffixUpdateConsumer(SEARCH_REMOTE_CLUSTER_SKIP_UNAVAILABLE, this::updateSkipUnavailable, (alias, value) -> {});
}
private synchronized void updateSkipUnavailable(String clusterAlias, Boolean skipUnavailable) {
RemoteClusterConnection remote = this.remoteClusters.get(clusterAlias);
if (remote != null) {
remote.updateSkipUnavailable(skipUnavailable);
}
}
@Override
protected void updateRemoteCluster(String clusterAlias, Settings settings) {
CountDownLatch latch = new CountDownLatch(1);
updateRemoteCluster(clusterAlias, settings, ActionListener.wrap(latch::countDown));
try {
// Wait 10 seconds for a connections. We must use a latch instead of a future because we
// are on the cluster state thread and our custom future implementation will throw an
// assertion.
if (latch.await(10, TimeUnit.SECONDS) == false) {
logger.warn("failed to connect to new remote cluster {} within {}", clusterAlias, TimeValue.timeValueSeconds(10));
}
} catch (InterruptedException e) {
Thread.currentThread().interrupt();
}
}
/**
* This method updates the list of remote clusters. It's intended to be used as an update consumer on the settings infrastructure
*
* @param clusterAlias a cluster alias to discovery node mapping representing the remote clusters seeds nodes
* @param newSettings the updated settings for the remote connection
* @param listener a listener invoked once every configured cluster has been connected to
*/
synchronized void updateRemoteCluster(String clusterAlias, Settings newSettings, ActionListener listener) {
if (LOCAL_CLUSTER_GROUP_KEY.equals(clusterAlias)) {
throw new IllegalArgumentException("remote clusters must not have the empty string as its key");
}
RemoteClusterConnection remote = this.remoteClusters.get(clusterAlias);
if (RemoteConnectionStrategy.isConnectionEnabled(clusterAlias, newSettings) == false) {
try {
IOUtils.close(remote);
} catch (IOException e) {
logger.warn("failed to close remote cluster connections for cluster: " + clusterAlias, e);
}
remoteClusters.remove(clusterAlias);
listener.onResponse(null);
return;
}
if (remote == null) {
// this is a new cluster we have to add a new representation
Settings finalSettings = Settings.builder().put(this.settings, false).put(newSettings, false).build();
remote = new RemoteClusterConnection(finalSettings, clusterAlias, transportService);
remoteClusters.put(clusterAlias, remote);
remote.ensureConnected(listener);
} else if (remote.shouldRebuildConnection(newSettings)) {
// Changes to connection configuration. Must tear down existing connection
try {
IOUtils.close(remote);
} catch (IOException e) {
logger.warn("failed to close remote cluster connections for cluster: " + clusterAlias, e);
}
remoteClusters.remove(clusterAlias);
Settings finalSettings = Settings.builder().put(this.settings, false).put(newSettings, false).build();
remote = new RemoteClusterConnection(finalSettings, clusterAlias, transportService);
remoteClusters.put(clusterAlias, remote);
remote.ensureConnected(listener);
} else {
// No changes to connection configuration.
listener.onResponse(null);
}
}
/**
* Connects to all remote clusters in a blocking fashion. This should be called on node startup to establish an initial connection
* to all configured seed nodes.
*/
void initializeRemoteClusters() {
final TimeValue timeValue = REMOTE_INITIAL_CONNECTION_TIMEOUT_SETTING.get(settings);
final PlainActionFuture> future = new PlainActionFuture<>();
Set enabledClusters = RemoteClusterAware.getEnabledRemoteClusters(settings);
if (enabledClusters.isEmpty()) {
return;
}
GroupedActionListener listener = new GroupedActionListener<>(future, enabledClusters.size());
for (String clusterAlias : enabledClusters) {
updateRemoteCluster(clusterAlias, settings, listener);
}
if (enabledClusters.isEmpty()) {
future.onResponse(null);
}
try {
future.get(timeValue.millis(), TimeUnit.MILLISECONDS);
} catch (InterruptedException e) {
Thread.currentThread().interrupt();
} catch (TimeoutException ex) {
logger.warn("failed to connect to remote clusters within {}", timeValue.toString());
} catch (Exception e) {
throw new IllegalStateException("failed to connect to remote clusters", e);
}
}
@Override
public void close() throws IOException {
IOUtils.close(remoteClusters.values());
}
public Stream getRemoteConnectionInfos() {
return remoteClusters.values().stream().map(RemoteClusterConnection::getConnectionInfo);
}
/**
* Collects all nodes of the given clusters and returns / passes a (clusterAlias, nodeId) to {@link DiscoveryNode}
* function on success.
*/
public void collectNodes(Set clusters, ActionListener> listener) {
Map remoteClusters = this.remoteClusters;
for (String cluster : clusters) {
if (remoteClusters.containsKey(cluster) == false) {
listener.onFailure(new NoSuchRemoteClusterException(cluster));
return;
}
}
final Map> clusterMap = new HashMap<>();
CountDown countDown = new CountDown(clusters.size());
Function nullFunction = s -> null;
for (final String cluster : clusters) {
RemoteClusterConnection connection = remoteClusters.get(cluster);
connection.collectNodes(new ActionListener>() {
@Override
public void onResponse(Function nodeLookup) {
synchronized (clusterMap) {
clusterMap.put(cluster, nodeLookup);
}
if (countDown.countDown()) {
listener.onResponse((clusterAlias, nodeId)
-> clusterMap.getOrDefault(clusterAlias, nullFunction).apply(nodeId));
}
}
@Override
public void onFailure(Exception e) {
if (countDown.fastForward()) { // we need to check if it's true since we could have multiple failures
listener.onFailure(e);
}
}
});
}
}
/**
* Returns a client to the remote cluster if the given cluster alias exists.
*
* @param threadPool the {@link ThreadPool} for the client
* @param clusterAlias the cluster alias the remote cluster is registered under
* @throws IllegalArgumentException if the given clusterAlias doesn't exist
*/
public Client getRemoteClusterClient(ThreadPool threadPool, String clusterAlias) {
if (transportService.getRemoteClusterService().getRemoteClusterNames().contains(clusterAlias) == false) {
throw new NoSuchRemoteClusterException(clusterAlias);
}
return new RemoteClusterAwareClient(settings, threadPool, transportService, clusterAlias);
}
Collection getConnections() {
return remoteClusters.values();
}
private static class RemoteConnectionEnabled implements Setting.Validator {
private final String clusterAlias;
private final String key;
private RemoteConnectionEnabled(String clusterAlias, String key) {
this.clusterAlias = clusterAlias;
this.key = key;
}
@Override
public void validate(T value) {
}
@Override
public void validate(T value, Map, Object> settings, boolean isPresent) {
if (isPresent && RemoteConnectionStrategy.isConnectionEnabled(clusterAlias, settings) == false) {
throw new IllegalArgumentException("Cannot configure setting [" + key + "] if remote cluster is not enabled.");
}
}
@Override
public Iterator> settings() {
return Stream.concat(Stream.of(RemoteConnectionStrategy.REMOTE_CONNECTION_MODE.getConcreteSettingForNamespace(clusterAlias)),
settingsStream()).iterator();
}
private Stream> settingsStream() {
return Arrays.stream(RemoteConnectionStrategy.ConnectionStrategy.values())
.flatMap(strategy -> strategy.getEnablementSettings().get())
.map(as -> as.getConcreteSettingForNamespace(clusterAlias));
}
};
}