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* 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.discovery.zen;
import org.elasticsearch.Version;
import org.elasticsearch.cluster.ClusterState;
import org.elasticsearch.cluster.metadata.IndexMetaData;
import org.elasticsearch.cluster.metadata.MetaData;
import org.elasticsearch.cluster.node.DiscoveryNode;
import org.elasticsearch.common.component.AbstractComponent;
import org.elasticsearch.common.io.stream.StreamInput;
import org.elasticsearch.common.io.stream.StreamOutput;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.common.unit.TimeValue;
import org.elasticsearch.threadpool.ThreadPool;
import org.elasticsearch.transport.EmptyTransportResponseHandler;
import org.elasticsearch.transport.TransportChannel;
import org.elasticsearch.transport.TransportRequest;
import org.elasticsearch.transport.TransportRequestHandler;
import org.elasticsearch.transport.TransportResponse;
import org.elasticsearch.transport.TransportService;
import java.io.IOException;
import java.util.concurrent.TimeUnit;
public class MembershipAction extends AbstractComponent {
public static final String DISCOVERY_JOIN_ACTION_NAME = "internal:discovery/zen/join";
public static final String DISCOVERY_JOIN_VALIDATE_ACTION_NAME = "internal:discovery/zen/join/validate";
public static final String DISCOVERY_LEAVE_ACTION_NAME = "internal:discovery/zen/leave";
public interface JoinCallback {
void onSuccess();
void onFailure(Exception e);
}
public interface MembershipListener {
void onJoin(DiscoveryNode node, JoinCallback callback);
void onLeave(DiscoveryNode node);
}
private final TransportService transportService;
private final MembershipListener listener;
public MembershipAction(Settings settings, TransportService transportService, MembershipListener listener) {
super(settings);
this.transportService = transportService;
this.listener = listener;
transportService.registerRequestHandler(DISCOVERY_JOIN_ACTION_NAME, JoinRequest::new,
ThreadPool.Names.GENERIC, new JoinRequestRequestHandler());
transportService.registerRequestHandler(DISCOVERY_JOIN_VALIDATE_ACTION_NAME,
() -> new ValidateJoinRequest(), ThreadPool.Names.GENERIC,
new ValidateJoinRequestRequestHandler());
transportService.registerRequestHandler(DISCOVERY_LEAVE_ACTION_NAME, LeaveRequest::new,
ThreadPool.Names.GENERIC, new LeaveRequestRequestHandler());
}
public void sendLeaveRequest(DiscoveryNode masterNode, DiscoveryNode node) {
transportService.sendRequest(node, DISCOVERY_LEAVE_ACTION_NAME, new LeaveRequest(masterNode),
EmptyTransportResponseHandler.INSTANCE_SAME);
}
public void sendLeaveRequestBlocking(DiscoveryNode masterNode, DiscoveryNode node, TimeValue timeout) {
transportService.submitRequest(masterNode, DISCOVERY_LEAVE_ACTION_NAME, new LeaveRequest(node),
EmptyTransportResponseHandler.INSTANCE_SAME).txGet(timeout.millis(), TimeUnit.MILLISECONDS);
}
public void sendJoinRequestBlocking(DiscoveryNode masterNode, DiscoveryNode node, TimeValue timeout) {
transportService.submitRequest(masterNode, DISCOVERY_JOIN_ACTION_NAME, new JoinRequest(node),
EmptyTransportResponseHandler.INSTANCE_SAME).txGet(timeout.millis(), TimeUnit.MILLISECONDS);
}
/**
* Validates the join request, throwing a failure if it failed.
*/
public void sendValidateJoinRequestBlocking(DiscoveryNode node, ClusterState state, TimeValue timeout) {
transportService.submitRequest(node, DISCOVERY_JOIN_VALIDATE_ACTION_NAME, new ValidateJoinRequest(state),
EmptyTransportResponseHandler.INSTANCE_SAME).txGet(timeout.millis(), TimeUnit.MILLISECONDS);
}
public static class JoinRequest extends TransportRequest {
DiscoveryNode node;
public JoinRequest() {
}
private JoinRequest(DiscoveryNode node) {
this.node = node;
}
@Override
public void readFrom(StreamInput in) throws IOException {
super.readFrom(in);
node = new DiscoveryNode(in);
}
@Override
public void writeTo(StreamOutput out) throws IOException {
super.writeTo(out);
node.writeTo(out);
}
}
private class JoinRequestRequestHandler implements TransportRequestHandler<JoinRequest> {
@Override
public void messageReceived(final JoinRequest request, final TransportChannel channel) throws Exception {
listener.onJoin(request.node, new JoinCallback() {
@Override
public void onSuccess() {
try {
channel.sendResponse(TransportResponse.Empty.INSTANCE);
} catch (Exception e) {
onFailure(e);
}
}
@Override
public void onFailure(Exception e) {
try {
channel.sendResponse(e);
} catch (Exception inner) {
inner.addSuppressed(e);
logger.warn("failed to send back failure on join request", inner);
}
}
});
}
}
static class ValidateJoinRequest extends TransportRequest {
private ClusterState state;
ValidateJoinRequest() {}
ValidateJoinRequest(ClusterState state) {
this.state = state;
}
@Override
public void readFrom(StreamInput in) throws IOException {
super.readFrom(in);
this.state = ClusterState.readFrom(in, null);
}
@Override
public void writeTo(StreamOutput out) throws IOException {
super.writeTo(out);
this.state.writeTo(out);
}
}
static class ValidateJoinRequestRequestHandler implements TransportRequestHandler<ValidateJoinRequest> {
@Override
public void messageReceived(ValidateJoinRequest request, TransportChannel channel) throws Exception {
ensureIndexCompatibility(Version.CURRENT, request.state.getMetaData());
// for now, the mere fact that we can serialize the cluster state acts as validation....
channel.sendResponse(TransportResponse.Empty.INSTANCE);
}
}
/**
* Ensures that all indices are compatible with the given node version. This will ensure that all indices in the given metadata
* will not be created with a newer version of elasticsearch as well as that all indices are newer or equal to the minimum index
* compatibility version.
* @see Version#minimumIndexCompatibilityVersion()
* @throws IllegalStateException if any index is incompatible with the given version
*/
static void ensureIndexCompatibility(final Version nodeVersion, MetaData metaData) {
Version supportedIndexVersion = nodeVersion.minimumIndexCompatibilityVersion();
// we ensure that all indices in the cluster we join are compatible with us no matter if they are
// closed or not we can't read mappings of these indices so we need to reject the join...
for (IndexMetaData idxMetaData : metaData) {
if (idxMetaData.getCreationVersion().after(nodeVersion)) {
throw new IllegalStateException("index " + idxMetaData.getIndex() + " version not supported: "
+ idxMetaData.getCreationVersion() + " the node version is: " + nodeVersion);
}
if (idxMetaData.getCreationVersion().before(supportedIndexVersion)) {
throw new IllegalStateException("index " + idxMetaData.getIndex() + " version not supported: "
+ idxMetaData.getCreationVersion() + " minimum compatible index version is: " + supportedIndexVersion);
}
}
}
public static class LeaveRequest extends TransportRequest {
private DiscoveryNode node;
public LeaveRequest() {
}
private LeaveRequest(DiscoveryNode node) {
this.node = node;
}
@Override
public void readFrom(StreamInput in) throws IOException {
super.readFrom(in);
node = new DiscoveryNode(in);
}
@Override
public void writeTo(StreamOutput out) throws IOException {
super.writeTo(out);
node.writeTo(out);
}
}
private class LeaveRequestRequestHandler implements TransportRequestHandler<LeaveRequest> {
@Override
public void messageReceived(LeaveRequest request, TransportChannel channel) throws Exception {
listener.onLeave(request.node);
channel.sendResponse(TransportResponse.Empty.INSTANCE);
}
}
}