2 * Copyright (c) 2017 Cisco Systems, Inc. and others. All rights reserved.
4 * This program and the accompanying materials are made available under the
5 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
6 * and is available at http://www.eclipse.org/legal/epl-v10.html
8 package org.opendaylight.controller.cluster.sharding;
10 import static akka.actor.ActorRef.noSender;
11 import static com.google.common.base.Preconditions.checkArgument;
12 import static com.google.common.base.Preconditions.checkState;
13 import static java.util.Objects.requireNonNull;
15 import akka.actor.ActorRef;
16 import akka.actor.PoisonPill;
17 import akka.dispatch.Futures;
18 import akka.dispatch.Mapper;
19 import akka.dispatch.OnComplete;
20 import akka.util.Timeout;
21 import java.util.Collection;
22 import java.util.Optional;
23 import java.util.concurrent.CompletionStage;
24 import java.util.concurrent.ConcurrentHashMap;
25 import org.opendaylight.controller.cluster.datastore.exceptions.LocalShardNotFoundException;
26 import org.opendaylight.controller.cluster.datastore.messages.MakeLeaderLocal;
27 import org.opendaylight.controller.cluster.datastore.utils.ActorUtils;
28 import org.opendaylight.controller.cluster.datastore.utils.ClusterUtils;
29 import org.opendaylight.controller.cluster.dom.api.CDSShardAccess;
30 import org.opendaylight.controller.cluster.dom.api.LeaderLocation;
31 import org.opendaylight.controller.cluster.dom.api.LeaderLocationListener;
32 import org.opendaylight.controller.cluster.dom.api.LeaderLocationListenerRegistration;
33 import org.opendaylight.controller.cluster.raft.LeadershipTransferFailedException;
34 import org.opendaylight.mdsal.dom.api.DOMDataTreeIdentifier;
35 import org.slf4j.Logger;
36 import org.slf4j.LoggerFactory;
37 import scala.compat.java8.FutureConverters;
38 import scala.concurrent.Future;
41 * Default {@link CDSShardAccess} implementation. Listens on leader location
42 * change events and distributes them to registered listeners. Also updates
43 * current information about leader location accordingly.
46 * Sends {@link MakeLeaderLocal} message to local shards and translates its result
47 * on behalf users {@link #makeLeaderLocal()} calls.
50 * {@link org.opendaylight.controller.cluster.dom.api.CDSDataTreeProducer} that
51 * creates instances of this class has to call {@link #close()} once it is no
54 final class CDSShardAccessImpl implements CDSShardAccess, LeaderLocationListener, AutoCloseable {
55 private static final Logger LOG = LoggerFactory.getLogger(CDSShardAccessImpl.class);
57 private final Collection<LeaderLocationListener> listeners = ConcurrentHashMap.newKeySet();
58 private final DOMDataTreeIdentifier prefix;
59 private final ActorUtils actorUtils;
60 private final Timeout makeLeaderLocalTimeout;
62 private ActorRef roleChangeListenerActor;
64 private volatile LeaderLocation currentLeader = LeaderLocation.UNKNOWN;
65 private volatile boolean closed = false;
67 CDSShardAccessImpl(final DOMDataTreeIdentifier prefix, final ActorUtils actorUtils) {
68 this.prefix = requireNonNull(prefix);
69 this.actorUtils = requireNonNull(actorUtils);
70 this.makeLeaderLocalTimeout =
71 new Timeout(actorUtils.getDatastoreContext().getShardLeaderElectionTimeout().duration().$times(2));
73 // register RoleChangeListenerActor
74 // TODO Maybe we should do this in async
75 final Optional<ActorRef> localShardReply =
76 actorUtils.findLocalShard(ClusterUtils.getCleanShardName(prefix.getRootIdentifier()));
77 checkState(localShardReply.isPresent(),
78 "Local shard for {} not present. Cannot register RoleChangeListenerActor", prefix);
79 roleChangeListenerActor =
80 actorUtils.getActorSystem().actorOf(RoleChangeListenerActor.props(localShardReply.get(), this));
83 private void checkNotClosed() {
84 checkState(!closed, "CDSDataTreeProducer, that this CDSShardAccess is associated with, is no longer valid");
88 public DOMDataTreeIdentifier getShardIdentifier() {
94 public LeaderLocation getLeaderLocation() {
96 // TODO before getting first notification from roleChangeListenerActor
97 // we will always return UNKNOWN
102 public CompletionStage<Void> makeLeaderLocal() {
103 // TODO when we have running make leader local operation
104 // we should just return the same completion stage
107 // TODO can we cache local shard actorRef?
108 final Future<ActorRef> localShardReply =
109 actorUtils.findLocalShardAsync(ClusterUtils.getCleanShardName(prefix.getRootIdentifier()));
111 // we have to tell local shard to make leader local
112 final scala.concurrent.Promise<Object> makeLeaderLocalAsk = Futures.promise();
113 localShardReply.onComplete(new OnComplete<ActorRef>() {
115 public void onComplete(final Throwable failure, final ActorRef actorRef) {
116 if (failure instanceof LocalShardNotFoundException) {
117 LOG.debug("No local shard found for {} - Cannot request leadership transfer to local shard.",
118 getShardIdentifier(), failure);
119 makeLeaderLocalAsk.failure(failure);
120 } else if (failure != null) {
121 // TODO should this be WARN?
122 LOG.debug("Failed to find local shard for {} - Cannot request leadership transfer to local shard.",
123 getShardIdentifier(), failure);
124 makeLeaderLocalAsk.failure(failure);
127 .completeWith(actorUtils
128 .executeOperationAsync(actorRef, MakeLeaderLocal.INSTANCE, makeLeaderLocalTimeout));
131 }, actorUtils.getClientDispatcher());
133 // we have to transform make leader local request result
134 Future<Void> makeLeaderLocalFuture = makeLeaderLocalAsk.future()
135 .transform(new Mapper<Object, Void>() {
137 public Void apply(final Object parameter) {
140 }, new Mapper<Throwable, Throwable>() {
142 public Throwable apply(final Throwable parameter) {
143 if (parameter instanceof LeadershipTransferFailedException) {
144 // do nothing with exception and just pass it as it is
147 // wrap exception in LeadershipTransferFailedEx
148 return new LeadershipTransferFailedException("Leadership transfer failed", parameter);
150 }, actorUtils.getClientDispatcher());
152 return FutureConverters.toJava(makeLeaderLocalFuture);
156 public <L extends LeaderLocationListener> LeaderLocationListenerRegistration<L>
157 registerLeaderLocationListener(final L listener) {
159 requireNonNull(listener);
160 checkArgument(!listeners.contains(listener), "Listener %s is already registered with ShardAccess %s", listener,
163 LOG.debug("Registering LeaderLocationListener {}", listener);
165 listeners.add(listener);
167 return new LeaderLocationListenerRegistration<L>() {
169 public L getInstance() {
174 public void close() {
175 listeners.remove(listener);
181 @SuppressWarnings("checkstyle:IllegalCatch")
182 public void onLeaderLocationChanged(final LeaderLocation location) {
184 // we are closed already. Do not dispatch any new leader location
189 LOG.debug("Received leader location change notification. New leader location: {}", location);
190 currentLeader = location;
191 listeners.forEach(listener -> {
193 listener.onLeaderLocationChanged(location);
194 } catch (Exception e) {
195 LOG.warn("Ignoring uncaught exception thrown be LeaderLocationListener {} "
196 + "during processing leader location change {}", listener, location, e);
202 public void close() {
203 // TODO should we also remove all listeners?
204 LOG.debug("Closing {} ShardAccess", prefix);
207 if (roleChangeListenerActor != null) {
208 // stop RoleChangeListenerActor
209 roleChangeListenerActor.tell(PoisonPill.getInstance(), noSender());
210 roleChangeListenerActor = null;