opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/shardmanager/ShardManager.java

   1 /*
   2  * Copyright (c) 2014 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   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
   7  */
   8
   9 package org.opendaylight.controller.cluster.datastore.shardmanager;
  10
  11 import static akka.pattern.Patterns.ask;
  12 import static java.util.Objects.requireNonNull;
  13
  14 import akka.actor.ActorRef;
  15 import akka.actor.Address;
  16 import akka.actor.Cancellable;
  17 import akka.actor.OneForOneStrategy;
  18 import akka.actor.PoisonPill;
  19 import akka.actor.Status;
  20 import akka.actor.SupervisorStrategy;
  21 import akka.actor.SupervisorStrategy.Directive;
  22 import akka.cluster.ClusterEvent;
  23 import akka.cluster.ClusterEvent.MemberWeaklyUp;
  24 import akka.cluster.Member;
  25 import akka.dispatch.Futures;
  26 import akka.dispatch.OnComplete;
  27 import akka.japi.Function;
  28 import akka.pattern.Patterns;
  29 import akka.persistence.DeleteSnapshotsFailure;
  30 import akka.persistence.DeleteSnapshotsSuccess;
  31 import akka.persistence.RecoveryCompleted;
  32 import akka.persistence.SaveSnapshotFailure;
  33 import akka.persistence.SaveSnapshotSuccess;
  34 import akka.persistence.SnapshotOffer;
  35 import akka.persistence.SnapshotSelectionCriteria;
  36 import akka.util.Timeout;
  37 import com.google.common.annotations.VisibleForTesting;
  38 import com.google.common.util.concurrent.SettableFuture;
  39 import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
  40 import java.util.ArrayList;
  41 import java.util.Collection;
  42 import java.util.Collections;
  43 import java.util.HashMap;
  44 import java.util.HashSet;
  45 import java.util.List;
  46 import java.util.Map;
  47 import java.util.Map.Entry;
  48 import java.util.Set;
  49 import java.util.concurrent.TimeUnit;
  50 import java.util.concurrent.TimeoutException;
  51 import java.util.function.Consumer;
  52 import java.util.function.Supplier;
  53 import org.opendaylight.controller.cluster.access.concepts.MemberName;
  54 import org.opendaylight.controller.cluster.common.actor.AbstractUntypedPersistentActorWithMetering;
  55 import org.opendaylight.controller.cluster.common.actor.Dispatchers;
  56 import org.opendaylight.controller.cluster.datastore.AbstractDataStore;
  57 import org.opendaylight.controller.cluster.datastore.ClusterWrapper;
  58 import org.opendaylight.controller.cluster.datastore.DatastoreContext;
  59 import org.opendaylight.controller.cluster.datastore.DatastoreContext.Builder;
  60 import org.opendaylight.controller.cluster.datastore.DatastoreContextFactory;
  61 import org.opendaylight.controller.cluster.datastore.Shard;
  62 import org.opendaylight.controller.cluster.datastore.config.Configuration;
  63 import org.opendaylight.controller.cluster.datastore.config.ModuleShardConfiguration;
  64 import org.opendaylight.controller.cluster.datastore.config.PrefixShardConfiguration;
  65 import org.opendaylight.controller.cluster.datastore.exceptions.AlreadyExistsException;
  66 import org.opendaylight.controller.cluster.datastore.exceptions.NoShardLeaderException;
  67 import org.opendaylight.controller.cluster.datastore.exceptions.NotInitializedException;
  68 import org.opendaylight.controller.cluster.datastore.exceptions.PrimaryNotFoundException;
  69 import org.opendaylight.controller.cluster.datastore.identifiers.ShardIdentifier;
  70 import org.opendaylight.controller.cluster.datastore.messages.ActorInitialized;
  71 import org.opendaylight.controller.cluster.datastore.messages.AddPrefixShardReplica;
  72 import org.opendaylight.controller.cluster.datastore.messages.AddShardReplica;
  73 import org.opendaylight.controller.cluster.datastore.messages.ChangeShardMembersVotingStatus;
  74 import org.opendaylight.controller.cluster.datastore.messages.CreateShard;
  75 import org.opendaylight.controller.cluster.datastore.messages.FindLocalShard;
  76 import org.opendaylight.controller.cluster.datastore.messages.FindPrimary;
  77 import org.opendaylight.controller.cluster.datastore.messages.FlipShardMembersVotingStatus;
  78 import org.opendaylight.controller.cluster.datastore.messages.GetShardRole;
  79 import org.opendaylight.controller.cluster.datastore.messages.GetShardRoleReply;
  80 import org.opendaylight.controller.cluster.datastore.messages.LocalPrimaryShardFound;
  81 import org.opendaylight.controller.cluster.datastore.messages.LocalShardFound;
  82 import org.opendaylight.controller.cluster.datastore.messages.LocalShardNotFound;
  83 import org.opendaylight.controller.cluster.datastore.messages.RemoteFindPrimary;
  84 import org.opendaylight.controller.cluster.datastore.messages.RemotePrimaryShardFound;
  85 import org.opendaylight.controller.cluster.datastore.messages.RemovePrefixShardReplica;
  86 import org.opendaylight.controller.cluster.datastore.messages.RemoveShardReplica;
  87 import org.opendaylight.controller.cluster.datastore.messages.ShardLeaderStateChanged;
  88 import org.opendaylight.controller.cluster.datastore.messages.UpdateSchemaContext;
  89 import org.opendaylight.controller.cluster.datastore.persisted.DatastoreSnapshot;
  90 import org.opendaylight.controller.cluster.datastore.persisted.ShardManagerSnapshot;
  91 import org.opendaylight.controller.cluster.datastore.utils.ClusterUtils;
  92 import org.opendaylight.controller.cluster.datastore.utils.CompositeOnComplete;
  93 import org.opendaylight.controller.cluster.datastore.utils.PrimaryShardInfoFutureCache;
  94 import org.opendaylight.controller.cluster.notifications.RegisterRoleChangeListener;
  95 import org.opendaylight.controller.cluster.notifications.RegisterRoleChangeListenerReply;
  96 import org.opendaylight.controller.cluster.notifications.RoleChangeNotification;
  97 import org.opendaylight.controller.cluster.raft.base.messages.FollowerInitialSyncUpStatus;
  98 import org.opendaylight.controller.cluster.raft.base.messages.SwitchBehavior;
  99 import org.opendaylight.controller.cluster.raft.client.messages.GetOnDemandRaftState;
 100 import org.opendaylight.controller.cluster.raft.client.messages.GetSnapshot;
 101 import org.opendaylight.controller.cluster.raft.client.messages.OnDemandRaftState;
 102 import org.opendaylight.controller.cluster.raft.client.messages.Shutdown;
 103 import org.opendaylight.controller.cluster.raft.messages.AddServer;
 104 import org.opendaylight.controller.cluster.raft.messages.AddServerReply;
 105 import org.opendaylight.controller.cluster.raft.messages.ChangeServersVotingStatus;
 106 import org.opendaylight.controller.cluster.raft.messages.RemoveServer;
 107 import org.opendaylight.controller.cluster.raft.messages.RemoveServerReply;
 108 import org.opendaylight.controller.cluster.raft.messages.ServerChangeReply;
 109 import org.opendaylight.controller.cluster.raft.messages.ServerChangeStatus;
 110 import org.opendaylight.controller.cluster.raft.messages.ServerRemoved;
 111 import org.opendaylight.controller.cluster.raft.policy.DisableElectionsRaftPolicy;
 112 import org.opendaylight.controller.cluster.sharding.PrefixedShardConfigUpdateHandler;
 113 import org.opendaylight.controller.cluster.sharding.messages.InitConfigListener;
 114 import org.opendaylight.controller.cluster.sharding.messages.PrefixShardCreated;
 115 import org.opendaylight.controller.cluster.sharding.messages.PrefixShardRemoved;
 116 import org.opendaylight.mdsal.dom.api.DOMDataTreeIdentifier;
 117 import org.opendaylight.yangtools.concepts.Registration;
 118 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
 119 import org.opendaylight.yangtools.yang.model.api.EffectiveModelContext;
 120 import org.slf4j.Logger;
 121 import org.slf4j.LoggerFactory;
 122 import scala.concurrent.ExecutionContext;
 123 import scala.concurrent.Future;
 124 import scala.concurrent.duration.FiniteDuration;
 125
 126 /**
 127  * Manages the shards for a data store. The ShardManager has the following jobs:
 128  * <ul>
 129  * <li> Create all the local shard replicas that belong on this cluster member
 130  * <li> Find the address of the local shard
 131  * <li> Find the primary replica for any given shard
 132  * <li> Monitor the cluster members and store their addresses
 133  * </ul>
 134  */
 135 class ShardManager extends AbstractUntypedPersistentActorWithMetering {
 136     private static final Logger LOG = LoggerFactory.getLogger(ShardManager.class);
 137
 138     // Stores a mapping between a shard name and it's corresponding information
 139     // Shard names look like inventory, topology etc and are as specified in
 140     // configuration
 141     @VisibleForTesting
 142     final Map<String, ShardInformation> localShards = new HashMap<>();
 143
 144     // The type of a ShardManager reflects the type of the datastore itself
 145     // A data store could be of type config/operational
 146     private final String type;
 147
 148     private final ClusterWrapper cluster;
 149
 150     private final Configuration configuration;
 151
 152     @VisibleForTesting
 153     final String shardDispatcherPath;
 154
 155     private final ShardManagerInfo shardManagerMBean;
 156
 157     private DatastoreContextFactory datastoreContextFactory;
 158
 159     private final SettableFuture<Void> readinessFuture;
 160
 161     private final PrimaryShardInfoFutureCache primaryShardInfoCache;
 162
 163     @VisibleForTesting
 164     final ShardPeerAddressResolver peerAddressResolver;
 165
 166     private EffectiveModelContext schemaContext;
 167
 168     private DatastoreSnapshot restoreFromSnapshot;
 169
 170     private ShardManagerSnapshot currentSnapshot;
 171
 172     private final Set<String> shardReplicaOperationsInProgress = new HashSet<>();
 173
 174     private final Map<String, CompositeOnComplete<Boolean>> shardActorsStopping = new HashMap<>();
 175
 176     private final Set<Consumer<String>> shardAvailabilityCallbacks = new HashSet<>();
 177
 178     private final String persistenceId;
 179     private final AbstractDataStore dataStore;
 180
 181     private PrefixedShardConfigUpdateHandler configUpdateHandler;
 182
 183     ShardManager(final AbstractShardManagerCreator<?> builder) {
 184         this.cluster = builder.getCluster();
 185         this.configuration = builder.getConfiguration();
 186         this.datastoreContextFactory = builder.getDatastoreContextFactory();
 187         this.type = datastoreContextFactory.getBaseDatastoreContext().getDataStoreName();
 188         this.shardDispatcherPath =
 189                 new Dispatchers(context().system().dispatchers()).getDispatcherPath(Dispatchers.DispatcherType.Shard);
 190         this.readinessFuture = builder.getReadinessFuture();
 191         this.primaryShardInfoCache = builder.getPrimaryShardInfoCache();
 192         this.restoreFromSnapshot = builder.getRestoreFromSnapshot();
 193
 194         String possiblePersistenceId = datastoreContextFactory.getBaseDatastoreContext().getShardManagerPersistenceId();
 195         persistenceId = possiblePersistenceId != null ? possiblePersistenceId : "shard-manager-" + type;
 196
 197         peerAddressResolver = new ShardPeerAddressResolver(type, cluster.getCurrentMemberName());
 198
 199         // Subscribe this actor to cluster member events
 200         cluster.subscribeToMemberEvents(getSelf());
 201
 202         shardManagerMBean = new ShardManagerInfo(getSelf(), cluster.getCurrentMemberName(),
 203                 "shard-manager-" + this.type,
 204                 datastoreContextFactory.getBaseDatastoreContext().getDataStoreMXBeanType());
 205         shardManagerMBean.registerMBean();
 206
 207         dataStore = builder.getDistributedDataStore();
 208     }
 209
 210     @Override
 211     public void preStart() {
 212         LOG.info("Starting ShardManager {}", persistenceId);
 213     }
 214
 215     @Override
 216     public void postStop() {
 217         LOG.info("Stopping ShardManager {}", persistenceId());
 218
 219         shardManagerMBean.unregisterMBean();
 220     }
 221
 222     @Override
 223     public void handleCommand(final Object message) throws Exception {
 224         if (message  instanceof FindPrimary) {
 225             findPrimary((FindPrimary)message);
 226         } else if (message instanceof FindLocalShard) {
 227             findLocalShard((FindLocalShard) message);
 228         } else if (message instanceof UpdateSchemaContext) {
 229             updateSchemaContext(message);
 230         } else if (message instanceof ActorInitialized) {
 231             onActorInitialized(message);
 232         } else if (message instanceof ClusterEvent.MemberUp) {
 233             memberUp((ClusterEvent.MemberUp) message);
 234         } else if (message instanceof ClusterEvent.MemberWeaklyUp) {
 235             memberWeaklyUp((ClusterEvent.MemberWeaklyUp) message);
 236         } else if (message instanceof ClusterEvent.MemberExited) {
 237             memberExited((ClusterEvent.MemberExited) message);
 238         } else if (message instanceof ClusterEvent.MemberRemoved) {
 239             memberRemoved((ClusterEvent.MemberRemoved) message);
 240         } else if (message instanceof ClusterEvent.UnreachableMember) {
 241             memberUnreachable((ClusterEvent.UnreachableMember) message);
 242         } else if (message instanceof ClusterEvent.ReachableMember) {
 243             memberReachable((ClusterEvent.ReachableMember) message);
 244         } else if (message instanceof DatastoreContextFactory) {
 245             onDatastoreContextFactory((DatastoreContextFactory) message);
 246         } else if (message instanceof RoleChangeNotification) {
 247             onRoleChangeNotification((RoleChangeNotification) message);
 248         } else if (message instanceof FollowerInitialSyncUpStatus) {
 249             onFollowerInitialSyncStatus((FollowerInitialSyncUpStatus) message);
 250         } else if (message instanceof ShardNotInitializedTimeout) {
 251             onShardNotInitializedTimeout((ShardNotInitializedTimeout) message);
 252         } else if (message instanceof ShardLeaderStateChanged) {
 253             onLeaderStateChanged((ShardLeaderStateChanged) message);
 254         } else if (message instanceof SwitchShardBehavior) {
 255             onSwitchShardBehavior((SwitchShardBehavior) message);
 256         } else if (message instanceof CreateShard) {
 257             onCreateShard((CreateShard)message);
 258         } else if (message instanceof AddShardReplica) {
 259             onAddShardReplica((AddShardReplica) message);
 260         } else if (message instanceof AddPrefixShardReplica) {
 261             onAddPrefixShardReplica((AddPrefixShardReplica) message);
 262         } else if (message instanceof PrefixShardCreated) {
 263             onPrefixShardCreated((PrefixShardCreated) message);
 264         } else if (message instanceof PrefixShardRemoved) {
 265             onPrefixShardRemoved((PrefixShardRemoved) message);
 266         } else if (message instanceof InitConfigListener) {
 267             onInitConfigListener();
 268         } else if (message instanceof ForwardedAddServerReply) {
 269             ForwardedAddServerReply msg = (ForwardedAddServerReply)message;
 270             onAddServerReply(msg.shardInfo, msg.addServerReply, getSender(), msg.leaderPath,
 271                     msg.removeShardOnFailure);
 272         } else if (message instanceof ForwardedAddServerFailure) {
 273             ForwardedAddServerFailure msg = (ForwardedAddServerFailure)message;
 274             onAddServerFailure(msg.shardName, msg.failureMessage, msg.failure, getSender(), msg.removeShardOnFailure);
 275         } else if (message instanceof RemoveShardReplica) {
 276             onRemoveShardReplica((RemoveShardReplica) message);
 277         } else if (message instanceof RemovePrefixShardReplica) {
 278             onRemovePrefixShardReplica((RemovePrefixShardReplica) message);
 279         } else if (message instanceof WrappedShardResponse) {
 280             onWrappedShardResponse((WrappedShardResponse) message);
 281         } else if (message instanceof GetSnapshot) {
 282             onGetSnapshot((GetSnapshot) message);
 283         } else if (message instanceof ServerRemoved) {
 284             onShardReplicaRemoved((ServerRemoved) message);
 285         } else if (message instanceof ChangeShardMembersVotingStatus) {
 286             onChangeShardServersVotingStatus((ChangeShardMembersVotingStatus) message);
 287         } else if (message instanceof FlipShardMembersVotingStatus) {
 288             onFlipShardMembersVotingStatus((FlipShardMembersVotingStatus) message);
 289         } else if (message instanceof SaveSnapshotSuccess) {
 290             onSaveSnapshotSuccess((SaveSnapshotSuccess) message);
 291         } else if (message instanceof SaveSnapshotFailure) {
 292             LOG.error("{}: SaveSnapshotFailure received for saving snapshot of shards", persistenceId(),
 293                     ((SaveSnapshotFailure) message).cause());
 294         } else if (message instanceof Shutdown) {
 295             onShutDown();
 296         } else if (message instanceof GetLocalShardIds) {
 297             onGetLocalShardIds();
 298         } else if (message instanceof GetShardRole) {
 299             onGetShardRole((GetShardRole) message);
 300         } else if (message instanceof RunnableMessage) {
 301             ((RunnableMessage)message).run();
 302         } else if (message instanceof RegisterForShardAvailabilityChanges) {
 303             onRegisterForShardAvailabilityChanges((RegisterForShardAvailabilityChanges)message);
 304         } else if (message instanceof DeleteSnapshotsFailure) {
 305             LOG.warn("{}: Failed to delete prior snapshots", persistenceId(),
 306                     ((DeleteSnapshotsFailure) message).cause());
 307         } else if (message instanceof DeleteSnapshotsSuccess) {
 308             LOG.debug("{}: Successfully deleted prior snapshots", persistenceId());
 309         } else if (message instanceof RegisterRoleChangeListenerReply) {
 310             LOG.trace("{}: Received RegisterRoleChangeListenerReply", persistenceId());
 311         } else if (message instanceof ClusterEvent.MemberEvent) {
 312             LOG.trace("{}: Received other ClusterEvent.MemberEvent: {}", persistenceId(), message);
 313         } else {
 314             unknownMessage(message);
 315         }
 316     }
 317
 318     private void onRegisterForShardAvailabilityChanges(final RegisterForShardAvailabilityChanges message) {
 319         LOG.debug("{}: onRegisterForShardAvailabilityChanges: {}", persistenceId(), message);
 320
 321         final Consumer<String> callback = message.getCallback();
 322         shardAvailabilityCallbacks.add(callback);
 323
 324         getSender().tell(new Status.Success((Registration)
 325             () -> executeInSelf(() -> shardAvailabilityCallbacks.remove(callback))), self());
 326     }
 327
 328     private void onGetShardRole(final GetShardRole message) {
 329         LOG.debug("{}: onGetShardRole for shard: {}", persistenceId(), message.getName());
 330
 331         final String name = message.getName();
 332
 333         final ShardInformation shardInformation = localShards.get(name);
 334
 335         if (shardInformation == null) {
 336             LOG.info("{}: no shard information for {} found", persistenceId(), name);
 337             getSender().tell(new Status.Failure(
 338                     new IllegalArgumentException("Shard with name " + name + " not present.")), ActorRef.noSender());
 339             return;
 340         }
 341
 342         getSender().tell(new GetShardRoleReply(shardInformation.getRole()), ActorRef.noSender());
 343     }
 344
 345     private void onInitConfigListener() {
 346         LOG.debug("{}: Initializing config listener on {}", persistenceId(), cluster.getCurrentMemberName());
 347
 348         final org.opendaylight.mdsal.common.api.LogicalDatastoreType datastoreType =
 349                 org.opendaylight.mdsal.common.api.LogicalDatastoreType
 350                         .valueOf(datastoreContextFactory.getBaseDatastoreContext().getLogicalStoreType().name());
 351
 352         if (configUpdateHandler != null) {
 353             configUpdateHandler.close();
 354         }
 355
 356         configUpdateHandler = new PrefixedShardConfigUpdateHandler(self(), cluster.getCurrentMemberName());
 357         configUpdateHandler.initListener(dataStore, datastoreType);
 358     }
 359
 360     void onShutDown() {
 361         List<Future<Boolean>> stopFutures = new ArrayList<>(localShards.size());
 362         for (ShardInformation info : localShards.values()) {
 363             if (info.getActor() != null) {
 364                 LOG.debug("{}: Issuing gracefulStop to shard {}", persistenceId(), info.getShardId());
 365
 366                 FiniteDuration duration = info.getDatastoreContext().getShardRaftConfig()
 367                         .getElectionTimeOutInterval().$times(2);
 368                 stopFutures.add(Patterns.gracefulStop(info.getActor(), duration, Shutdown.INSTANCE));
 369             }
 370         }
 371
 372         LOG.info("Shutting down ShardManager {} - waiting on {} shards", persistenceId(), stopFutures.size());
 373
 374         ExecutionContext dispatcher = new Dispatchers(context().system().dispatchers())
 375                 .getDispatcher(Dispatchers.DispatcherType.Client);
 376         Future<Iterable<Boolean>> combinedFutures = Futures.sequence(stopFutures, dispatcher);
 377
 378         combinedFutures.onComplete(new OnComplete<Iterable<Boolean>>() {
 379             @Override
 380             public void onComplete(final Throwable failure, final Iterable<Boolean> results) {
 381                 LOG.debug("{}: All shards shutdown - sending PoisonPill to self", persistenceId());
 382
 383                 self().tell(PoisonPill.getInstance(), self());
 384
 385                 if (failure != null) {
 386                     LOG.warn("{}: An error occurred attempting to shut down the shards", persistenceId(), failure);
 387                 } else {
 388                     int nfailed = 0;
 389                     for (Boolean result : results) {
 390                         if (!result) {
 391                             nfailed++;
 392                         }
 393                     }
 394
 395                     if (nfailed > 0) {
 396                         LOG.warn("{}: {} shards did not shut down gracefully", persistenceId(), nfailed);
 397                     }
 398                 }
 399             }
 400         }, dispatcher);
 401     }
 402
 403     private void onWrappedShardResponse(final WrappedShardResponse message) {
 404         if (message.getResponse() instanceof RemoveServerReply) {
 405             onRemoveServerReply(getSender(), message.getShardId(), (RemoveServerReply) message.getResponse(),
 406                     message.getLeaderPath());
 407         }
 408     }
 409
 410     private void onRemoveServerReply(final ActorRef originalSender, final ShardIdentifier shardId,
 411             final RemoveServerReply replyMsg, final String leaderPath) {
 412         shardReplicaOperationsInProgress.remove(shardId.getShardName());
 413
 414         LOG.debug("{}: Received {} for shard {}", persistenceId(), replyMsg, shardId.getShardName());
 415
 416         if (replyMsg.getStatus() == ServerChangeStatus.OK) {
 417             LOG.debug("{}: Leader shard successfully removed the replica shard {}", persistenceId(),
 418                     shardId.getShardName());
 419             originalSender.tell(new Status.Success(null), getSelf());
 420         } else {
 421             LOG.warn("{}: Leader failed to remove shard replica {} with status {}",
 422                     persistenceId(), shardId, replyMsg.getStatus());
 423
 424             Exception failure = getServerChangeException(RemoveServer.class, replyMsg.getStatus(), leaderPath, shardId);
 425             originalSender.tell(new Status.Failure(failure), getSelf());
 426         }
 427     }
 428
 429     @SuppressFBWarnings(value = "UPM_UNCALLED_PRIVATE_METHOD",
 430             justification = "https://github.com/spotbugs/spotbugs/issues/811")
 431     private void removePrefixShardReplica(final RemovePrefixShardReplica contextMessage, final String shardName,
 432                                           final String primaryPath, final ActorRef sender) {
 433         if (isShardReplicaOperationInProgress(shardName, sender)) {
 434             return;
 435         }
 436
 437         shardReplicaOperationsInProgress.add(shardName);
 438
 439         final ShardIdentifier shardId = getShardIdentifier(contextMessage.getMemberName(), shardName);
 440
 441         final DatastoreContext datastoreContext = newShardDatastoreContextBuilder(shardName).build();
 442
 443         //inform ShardLeader to remove this shard as a replica by sending an RemoveServer message
 444         LOG.debug("{}: Sending RemoveServer message to peer {} for shard {}", persistenceId(),
 445                 primaryPath, shardId);
 446
 447         Timeout removeServerTimeout = new Timeout(datastoreContext.getShardLeaderElectionTimeout().duration());
 448         Future<Object> futureObj = ask(getContext().actorSelection(primaryPath),
 449                 new RemoveServer(shardId.toString()), removeServerTimeout);
 450
 451         futureObj.onComplete(new OnComplete<>() {
 452             @Override
 453             public void onComplete(final Throwable failure, final Object response) {
 454                 if (failure != null) {
 455                     shardReplicaOperationsInProgress.remove(shardName);
 456
 457                     LOG.debug("{}: RemoveServer request to leader {} for shard {} failed", persistenceId(), primaryPath,
 458                         shardName, failure);
 459
 460                     // FAILURE
 461                     sender.tell(new Status.Failure(new RuntimeException(
 462                         String.format("RemoveServer request to leader %s for shard %s failed", primaryPath, shardName),
 463                         failure)), self());
 464                 } else {
 465                     // SUCCESS
 466                     self().tell(new WrappedShardResponse(shardId, response, primaryPath), sender);
 467                 }
 468             }
 469         }, new Dispatchers(context().system().dispatchers()).getDispatcher(Dispatchers.DispatcherType.Client));
 470     }
 471
 472     @SuppressFBWarnings(value = "UPM_UNCALLED_PRIVATE_METHOD",
 473             justification = "https://github.com/spotbugs/spotbugs/issues/811")
 474     private void removeShardReplica(final RemoveShardReplica contextMessage, final String shardName,
 475             final String primaryPath, final ActorRef sender) {
 476         if (isShardReplicaOperationInProgress(shardName, sender)) {
 477             return;
 478         }
 479
 480         shardReplicaOperationsInProgress.add(shardName);
 481
 482         final ShardIdentifier shardId = getShardIdentifier(contextMessage.getMemberName(), shardName);
 483
 484         final DatastoreContext datastoreContext = newShardDatastoreContextBuilder(shardName).build();
 485
 486         //inform ShardLeader to remove this shard as a replica by sending an RemoveServer message
 487         LOG.debug("{}: Sending RemoveServer message to peer {} for shard {}", persistenceId(),
 488                 primaryPath, shardId);
 489
 490         Timeout removeServerTimeout = new Timeout(datastoreContext.getShardLeaderElectionTimeout().duration());
 491         Future<Object> futureObj = ask(getContext().actorSelection(primaryPath),
 492                 new RemoveServer(shardId.toString()), removeServerTimeout);
 493
 494         futureObj.onComplete(new OnComplete<>() {
 495             @Override
 496             public void onComplete(final Throwable failure, final Object response) {
 497                 if (failure != null) {
 498                     shardReplicaOperationsInProgress.remove(shardName);
 499                     LOG.debug("{}: RemoveServer request to leader {} for shard {} failed", persistenceId(), primaryPath,
 500                         shardName, failure);
 501
 502                     // FAILURE
 503                     sender.tell(new Status.Failure(new RuntimeException(
 504                         String.format("RemoveServer request to leader %s for shard %s failed", primaryPath, shardName),
 505                         failure)), self());
 506                 } else {
 507                     // SUCCESS
 508                     self().tell(new WrappedShardResponse(shardId, response, primaryPath), sender);
 509                 }
 510             }
 511         }, new Dispatchers(context().system().dispatchers()).getDispatcher(Dispatchers.DispatcherType.Client));
 512     }
 513
 514     private void onShardReplicaRemoved(final ServerRemoved message) {
 515         removeShard(new ShardIdentifier.Builder().fromShardIdString(message.getServerId()).build());
 516     }
 517
 518     @SuppressWarnings("checkstyle:IllegalCatch")
 519     private void removeShard(final ShardIdentifier shardId) {
 520         final String shardName = shardId.getShardName();
 521         final ShardInformation shardInformation = localShards.remove(shardName);
 522         if (shardInformation == null) {
 523             LOG.debug("{} : Shard replica {} is not present in list", persistenceId(), shardId.toString());
 524             return;
 525         }
 526
 527         final ActorRef shardActor = shardInformation.getActor();
 528         if (shardActor != null) {
 529             long timeoutInMS = Math.max(shardInformation.getDatastoreContext().getShardRaftConfig()
 530                     .getElectionTimeOutInterval().$times(3).toMillis(), 10000);
 531
 532             LOG.debug("{} : Sending Shutdown to Shard actor {} with {} ms timeout", persistenceId(), shardActor,
 533                     timeoutInMS);
 534
 535             final Future<Boolean> stopFuture = Patterns.gracefulStop(shardActor,
 536                     FiniteDuration.apply(timeoutInMS, TimeUnit.MILLISECONDS), Shutdown.INSTANCE);
 537
 538             final CompositeOnComplete<Boolean> onComplete = new CompositeOnComplete<>() {
 539                 @Override
 540                 public void onComplete(final Throwable failure, final Boolean result) {
 541                     if (failure == null) {
 542                         LOG.debug("{} : Successfully shut down Shard actor {}", persistenceId(), shardActor);
 543                     } else {
 544                         LOG.warn("{}: Failed to shut down Shard actor {}", persistenceId(), shardActor, failure);
 545                     }
 546
 547                     self().tell((RunnableMessage) () -> {
 548                         // At any rate, invalidate primaryShardInfo cache
 549                         primaryShardInfoCache.remove(shardName);
 550
 551                         shardActorsStopping.remove(shardName);
 552                         notifyOnCompleteTasks(failure, result);
 553                     }, ActorRef.noSender());
 554                 }
 555             };
 556
 557             shardActorsStopping.put(shardName, onComplete);
 558             stopFuture.onComplete(onComplete, new Dispatchers(context().system().dispatchers())
 559                     .getDispatcher(Dispatchers.DispatcherType.Client));
 560         }
 561
 562         LOG.debug("{} : Local Shard replica for shard {} has been removed", persistenceId(), shardName);
 563         persistShardList();
 564     }
 565
 566     private void onGetSnapshot(final GetSnapshot getSnapshot) {
 567         LOG.debug("{}: onGetSnapshot", persistenceId());
 568
 569         List<String> notInitialized = null;
 570         for (ShardInformation shardInfo : localShards.values()) {
 571             if (!shardInfo.isShardInitialized()) {
 572                 if (notInitialized == null) {
 573                     notInitialized = new ArrayList<>();
 574                 }
 575
 576                 notInitialized.add(shardInfo.getShardName());
 577             }
 578         }
 579
 580         if (notInitialized != null) {
 581             getSender().tell(new Status.Failure(new IllegalStateException(String.format(
 582                     "%d shard(s) %s are not initialized", notInitialized.size(), notInitialized))), getSelf());
 583             return;
 584         }
 585
 586         ActorRef replyActor = getContext().actorOf(ShardManagerGetSnapshotReplyActor.props(
 587                 new ArrayList<>(localShards.keySet()), type, currentSnapshot , getSender(), persistenceId(),
 588                 datastoreContextFactory.getBaseDatastoreContext().getShardInitializationTimeout().duration()));
 589
 590         for (ShardInformation shardInfo: localShards.values()) {
 591             shardInfo.getActor().tell(getSnapshot, replyActor);
 592         }
 593     }
 594
 595     @SuppressWarnings("checkstyle:IllegalCatch")
 596     private void onCreateShard(final CreateShard createShard) {
 597         LOG.debug("{}: onCreateShard: {}", persistenceId(), createShard);
 598
 599         Object reply;
 600         try {
 601             String shardName = createShard.getModuleShardConfig().getShardName();
 602             if (localShards.containsKey(shardName)) {
 603                 LOG.debug("{}: Shard {} already exists", persistenceId(), shardName);
 604                 reply = new Status.Success(String.format("Shard with name %s already exists", shardName));
 605             } else {
 606                 doCreateShard(createShard);
 607                 reply = new Status.Success(null);
 608             }
 609         } catch (Exception e) {
 610             LOG.error("{}: onCreateShard failed", persistenceId(), e);
 611             reply = new Status.Failure(e);
 612         }
 613
 614         if (getSender() != null && !getContext().system().deadLetters().equals(getSender())) {
 615             getSender().tell(reply, getSelf());
 616         }
 617     }
 618
 619     private void onPrefixShardCreated(final PrefixShardCreated message) {
 620         LOG.debug("{}: onPrefixShardCreated: {}", persistenceId(), message);
 621
 622         final PrefixShardConfiguration config = message.getConfiguration();
 623         final ShardIdentifier shardId = getShardIdentifier(cluster.getCurrentMemberName(),
 624                 ClusterUtils.getCleanShardName(config.getPrefix().getRootIdentifier()));
 625         final String shardName = shardId.getShardName();
 626
 627         if (isPreviousShardActorStopInProgress(shardName, message)) {
 628             return;
 629         }
 630
 631         if (localShards.containsKey(shardName)) {
 632             LOG.debug("{}: Received create for an already existing shard {}", persistenceId(), shardName);
 633             final PrefixShardConfiguration existing =
 634                     configuration.getAllPrefixShardConfigurations().get(config.getPrefix());
 635
 636             if (existing != null && existing.equals(config)) {
 637                 // we don't have to do nothing here
 638                 return;
 639             }
 640         }
 641
 642         doCreatePrefixShard(config, shardId, shardName);
 643     }
 644
 645     private boolean isPreviousShardActorStopInProgress(final String shardName, final Object messageToDefer) {
 646         final CompositeOnComplete<Boolean> stopOnComplete = shardActorsStopping.get(shardName);
 647         if (stopOnComplete == null) {
 648             return false;
 649         }
 650
 651         LOG.debug("{} : Stop is in progress for shard {} - adding OnComplete callback to defer {}", persistenceId(),
 652                 shardName, messageToDefer);
 653         final ActorRef sender = getSender();
 654         stopOnComplete.addOnComplete(new OnComplete<Boolean>() {
 655             @Override
 656             public void onComplete(final Throwable failure, final Boolean result) {
 657                 LOG.debug("{} : Stop complete for shard {} - re-queing {}", persistenceId(), shardName, messageToDefer);
 658                 self().tell(messageToDefer, sender);
 659             }
 660         });
 661
 662         return true;
 663     }
 664
 665     private void doCreatePrefixShard(final PrefixShardConfiguration config, final ShardIdentifier shardId,
 666             final String shardName) {
 667         configuration.addPrefixShardConfiguration(config);
 668
 669         final Builder builder = newShardDatastoreContextBuilder(shardName);
 670         builder.logicalStoreType(config.getPrefix().getDatastoreType())
 671                 .storeRoot(config.getPrefix().getRootIdentifier());
 672         DatastoreContext shardDatastoreContext = builder.build();
 673
 674         final Map<String, String> peerAddresses = getPeerAddresses(shardName);
 675         final boolean isActiveMember = true;
 676
 677         LOG.debug("{} doCreatePrefixShard: shardId: {}, memberNames: {}, peerAddresses: {}, isActiveMember: {}",
 678                 persistenceId(), shardId, config.getShardMemberNames(), peerAddresses, isActiveMember);
 679
 680         final ShardInformation info = new ShardInformation(shardName, shardId, peerAddresses,
 681                 shardDatastoreContext, Shard.builder(), peerAddressResolver);
 682         info.setActiveMember(isActiveMember);
 683         localShards.put(info.getShardName(), info);
 684
 685         if (schemaContext != null) {
 686             info.setSchemaContext(schemaContext);
 687             info.setActor(newShardActor(info));
 688         }
 689     }
 690
 691     private void onPrefixShardRemoved(final PrefixShardRemoved message) {
 692         LOG.debug("{}: onPrefixShardRemoved : {}", persistenceId(), message);
 693
 694         final DOMDataTreeIdentifier prefix = message.getPrefix();
 695         final ShardIdentifier shardId = getShardIdentifier(cluster.getCurrentMemberName(),
 696                 ClusterUtils.getCleanShardName(prefix.getRootIdentifier()));
 697
 698         configuration.removePrefixShardConfiguration(prefix);
 699         removeShard(shardId);
 700     }
 701
 702     private void doCreateShard(final CreateShard createShard) {
 703         final ModuleShardConfiguration moduleShardConfig = createShard.getModuleShardConfig();
 704         final String shardName = moduleShardConfig.getShardName();
 705
 706         configuration.addModuleShardConfiguration(moduleShardConfig);
 707
 708         DatastoreContext shardDatastoreContext = createShard.getDatastoreContext();
 709         if (shardDatastoreContext == null) {
 710             shardDatastoreContext = newShardDatastoreContext(shardName);
 711         } else {
 712             shardDatastoreContext = DatastoreContext.newBuilderFrom(shardDatastoreContext).shardPeerAddressResolver(
 713                     peerAddressResolver).build();
 714         }
 715
 716         ShardIdentifier shardId = getShardIdentifier(cluster.getCurrentMemberName(), shardName);
 717
 718         boolean shardWasInRecoveredSnapshot = currentSnapshot != null
 719                 && currentSnapshot.getShardList().contains(shardName);
 720
 721         Map<String, String> peerAddresses;
 722         boolean isActiveMember;
 723         if (shardWasInRecoveredSnapshot || configuration.getMembersFromShardName(shardName)
 724                 .contains(cluster.getCurrentMemberName())) {
 725             peerAddresses = getPeerAddresses(shardName);
 726             isActiveMember = true;
 727         } else {
 728             // The local member is not in the static shard member configuration and the shard did not
 729             // previously exist (ie !shardWasInRecoveredSnapshot). In this case we'll create
 730             // the shard with no peers and with elections disabled so it stays as follower. A
 731             // subsequent AddServer request will be needed to make it an active member.
 732             isActiveMember = false;
 733             peerAddresses = Collections.emptyMap();
 734             shardDatastoreContext = DatastoreContext.newBuilderFrom(shardDatastoreContext)
 735                     .customRaftPolicyImplementation(DisableElectionsRaftPolicy.class.getName()).build();
 736         }
 737
 738         LOG.debug("{} doCreateShard: shardId: {}, memberNames: {}, peerAddresses: {}, isActiveMember: {}",
 739                 persistenceId(), shardId, moduleShardConfig.getShardMemberNames(), peerAddresses,
 740                 isActiveMember);
 741
 742         ShardInformation info = new ShardInformation(shardName, shardId, peerAddresses,
 743                 shardDatastoreContext, createShard.getShardBuilder(), peerAddressResolver);
 744         info.setActiveMember(isActiveMember);
 745         localShards.put(info.getShardName(), info);
 746
 747         if (schemaContext != null) {
 748             info.setSchemaContext(schemaContext);
 749             info.setActor(newShardActor(info));
 750         }
 751     }
 752
 753     private DatastoreContext.Builder newShardDatastoreContextBuilder(final String shardName) {
 754         return DatastoreContext.newBuilderFrom(datastoreContextFactory.getShardDatastoreContext(shardName))
 755                 .shardPeerAddressResolver(peerAddressResolver);
 756     }
 757
 758     private DatastoreContext newShardDatastoreContext(final String shardName) {
 759         return newShardDatastoreContextBuilder(shardName).build();
 760     }
 761
 762     private void checkReady() {
 763         if (isReadyWithLeaderId()) {
 764             LOG.info("{}: All Shards are ready - data store {} is ready", persistenceId(), type);
 765             readinessFuture.set(null);
 766         }
 767     }
 768
 769     private void onLeaderStateChanged(final ShardLeaderStateChanged leaderStateChanged) {
 770         LOG.info("{}: Received LeaderStateChanged message: {}", persistenceId(), leaderStateChanged);
 771
 772         ShardInformation shardInformation = findShardInformation(leaderStateChanged.getMemberId());
 773         if (shardInformation != null) {
 774             shardInformation.setLocalDataTree(leaderStateChanged.getLocalShardDataTree());
 775             shardInformation.setLeaderVersion(leaderStateChanged.getLeaderPayloadVersion());
 776             if (shardInformation.setLeaderId(leaderStateChanged.getLeaderId())) {
 777                 primaryShardInfoCache.remove(shardInformation.getShardName());
 778
 779                 notifyShardAvailabilityCallbacks(shardInformation);
 780             }
 781
 782             checkReady();
 783         } else {
 784             LOG.debug("No shard found with member Id {}", leaderStateChanged.getMemberId());
 785         }
 786     }
 787
 788     private void notifyShardAvailabilityCallbacks(final ShardInformation shardInformation) {
 789         shardAvailabilityCallbacks.forEach(callback -> callback.accept(shardInformation.getShardName()));
 790     }
 791
 792     private void onShardNotInitializedTimeout(final ShardNotInitializedTimeout message) {
 793         ShardInformation shardInfo = message.getShardInfo();
 794
 795         LOG.debug("{}: Received ShardNotInitializedTimeout message for shard {}", persistenceId(),
 796                 shardInfo.getShardName());
 797
 798         shardInfo.removeOnShardInitialized(message.getOnShardInitialized());
 799
 800         if (!shardInfo.isShardInitialized()) {
 801             LOG.debug("{}: Returning NotInitializedException for shard {}", persistenceId(), shardInfo.getShardName());
 802             message.getSender().tell(createNotInitializedException(shardInfo.getShardId()), getSelf());
 803         } else {
 804             LOG.debug("{}: Returning NoShardLeaderException for shard {}", persistenceId(), shardInfo.getShardName());
 805             message.getSender().tell(new NoShardLeaderException(shardInfo.getShardId()), getSelf());
 806         }
 807     }
 808
 809     private void onFollowerInitialSyncStatus(final FollowerInitialSyncUpStatus status) {
 810         LOG.info("{} Received follower initial sync status for {} status sync done {}", persistenceId(),
 811                 status.getName(), status.isInitialSyncDone());
 812
 813         ShardInformation shardInformation = findShardInformation(status.getName());
 814
 815         if (shardInformation != null) {
 816             shardInformation.setFollowerSyncStatus(status.isInitialSyncDone());
 817
 818             shardManagerMBean.setSyncStatus(isInSync());
 819         }
 820
 821     }
 822
 823     private void onRoleChangeNotification(final RoleChangeNotification roleChanged) {
 824         LOG.info("{}: Received role changed for {} from {} to {}", persistenceId(), roleChanged.getMemberId(),
 825                 roleChanged.getOldRole(), roleChanged.getNewRole());
 826
 827         ShardInformation shardInformation = findShardInformation(roleChanged.getMemberId());
 828         if (shardInformation != null) {
 829             shardInformation.setRole(roleChanged.getNewRole());
 830             checkReady();
 831             shardManagerMBean.setSyncStatus(isInSync());
 832         }
 833     }
 834
 835
 836     private ShardInformation findShardInformation(final String memberId) {
 837         for (ShardInformation info : localShards.values()) {
 838             if (info.getShardId().toString().equals(memberId)) {
 839                 return info;
 840             }
 841         }
 842
 843         return null;
 844     }
 845
 846     private boolean isReadyWithLeaderId() {
 847         boolean isReady = true;
 848         for (ShardInformation info : localShards.values()) {
 849             if (!info.isShardReadyWithLeaderId()) {
 850                 isReady = false;
 851                 break;
 852             }
 853         }
 854         return isReady;
 855     }
 856
 857     private boolean isInSync() {
 858         for (ShardInformation info : localShards.values()) {
 859             if (!info.isInSync()) {
 860                 return false;
 861             }
 862         }
 863         return true;
 864     }
 865
 866     private void onActorInitialized(final Object message) {
 867         final ActorRef sender = getSender();
 868
 869         if (sender == null) {
 870             // why is a non-actor sending this message? Just ignore.
 871             return;
 872         }
 873
 874         String actorName = sender.path().name();
 875         //find shard name from actor name; actor name is stringified shardId
 876
 877         final ShardIdentifier shardId;
 878         try {
 879             shardId = ShardIdentifier.fromShardIdString(actorName);
 880         } catch (IllegalArgumentException e) {
 881             LOG.debug("{}: ignoring actor {}", persistenceId, actorName, e);
 882             return;
 883         }
 884
 885         markShardAsInitialized(shardId.getShardName());
 886     }
 887
 888     private void markShardAsInitialized(final String shardName) {
 889         LOG.debug("{}: Initializing shard [{}]", persistenceId(), shardName);
 890
 891         ShardInformation shardInformation = localShards.get(shardName);
 892         if (shardInformation != null) {
 893             shardInformation.setActorInitialized();
 894
 895             shardInformation.getActor().tell(new RegisterRoleChangeListener(), self());
 896         }
 897     }
 898
 899     @Override
 900     protected void handleRecover(final Object message) throws Exception {
 901         if (message instanceof RecoveryCompleted) {
 902             onRecoveryCompleted();
 903         } else if (message instanceof SnapshotOffer) {
 904             applyShardManagerSnapshot((ShardManagerSnapshot)((SnapshotOffer) message).snapshot());
 905         }
 906     }
 907
 908     @SuppressWarnings("checkstyle:IllegalCatch")
 909     private void onRecoveryCompleted() {
 910         LOG.info("Recovery complete : {}", persistenceId());
 911
 912         if (currentSnapshot == null && restoreFromSnapshot != null
 913                 && restoreFromSnapshot.getShardManagerSnapshot() != null) {
 914             ShardManagerSnapshot snapshot = restoreFromSnapshot.getShardManagerSnapshot();
 915
 916             LOG.debug("{}: Restoring from ShardManagerSnapshot: {}", persistenceId(), snapshot);
 917
 918             applyShardManagerSnapshot(snapshot);
 919         }
 920
 921         createLocalShards();
 922     }
 923
 924     private void sendResponse(final ShardInformation shardInformation, final boolean doWait,
 925             final boolean wantShardReady, final Supplier<Object> messageSupplier) {
 926         if (!shardInformation.isShardInitialized() || wantShardReady && !shardInformation.isShardReadyWithLeaderId()) {
 927             if (doWait) {
 928                 final ActorRef sender = getSender();
 929                 final ActorRef self = self();
 930
 931                 Runnable replyRunnable = () -> sender.tell(messageSupplier.get(), self);
 932
 933                 OnShardInitialized onShardInitialized = wantShardReady ? new OnShardReady(replyRunnable) :
 934                     new OnShardInitialized(replyRunnable);
 935
 936                 shardInformation.addOnShardInitialized(onShardInitialized);
 937
 938                 FiniteDuration timeout = shardInformation.getDatastoreContext()
 939                         .getShardInitializationTimeout().duration();
 940                 if (shardInformation.isShardInitialized()) {
 941                     // If the shard is already initialized then we'll wait enough time for the shard to
 942                     // elect a leader, ie 2 times the election timeout.
 943                     timeout = FiniteDuration.create(shardInformation.getDatastoreContext().getShardRaftConfig()
 944                             .getElectionTimeOutInterval().toMillis() * 2, TimeUnit.MILLISECONDS);
 945                 }
 946
 947                 LOG.debug("{}: Scheduling {} ms timer to wait for shard {}", persistenceId(), timeout.toMillis(),
 948                         shardInformation);
 949
 950                 Cancellable timeoutSchedule = getContext().system().scheduler().scheduleOnce(
 951                         timeout, getSelf(),
 952                         new ShardNotInitializedTimeout(shardInformation, onShardInitialized, sender),
 953                         getContext().dispatcher(), getSelf());
 954
 955                 onShardInitialized.setTimeoutSchedule(timeoutSchedule);
 956
 957             } else if (!shardInformation.isShardInitialized()) {
 958                 LOG.debug("{}: Returning NotInitializedException for shard {}", persistenceId(),
 959                         shardInformation.getShardName());
 960                 getSender().tell(createNotInitializedException(shardInformation.getShardId()), getSelf());
 961             } else {
 962                 LOG.debug("{}: Returning NoShardLeaderException for shard {}", persistenceId(),
 963                         shardInformation.getShardName());
 964                 getSender().tell(new NoShardLeaderException(shardInformation.getShardId()), getSelf());
 965             }
 966
 967             return;
 968         }
 969
 970         getSender().tell(messageSupplier.get(), getSelf());
 971     }
 972
 973     private static NotInitializedException createNotInitializedException(final ShardIdentifier shardId) {
 974         return new NotInitializedException(String.format(
 975                 "Found primary shard %s but it's not initialized yet. Please try again later", shardId));
 976     }
 977
 978     @VisibleForTesting
 979     static MemberName memberToName(final Member member) {
 980         return MemberName.forName(member.roles().iterator().next());
 981     }
 982
 983     private void memberRemoved(final ClusterEvent.MemberRemoved message) {
 984         MemberName memberName = memberToName(message.member());
 985
 986         LOG.info("{}: Received MemberRemoved: memberName: {}, address: {}", persistenceId(), memberName,
 987                 message.member().address());
 988
 989         peerAddressResolver.removePeerAddress(memberName);
 990
 991         for (ShardInformation info : localShards.values()) {
 992             info.peerDown(memberName, getShardIdentifier(memberName, info.getShardName()).toString(), getSelf());
 993         }
 994     }
 995
 996     private void memberExited(final ClusterEvent.MemberExited message) {
 997         MemberName memberName = memberToName(message.member());
 998
 999         LOG.info("{}: Received MemberExited: memberName: {}, address: {}", persistenceId(), memberName,
1000                 message.member().address());
1001
1002         peerAddressResolver.removePeerAddress(memberName);
1003
1004         for (ShardInformation info : localShards.values()) {
1005             info.peerDown(memberName, getShardIdentifier(memberName, info.getShardName()).toString(), getSelf());
1006         }
1007     }
1008
1009     private void memberUp(final ClusterEvent.MemberUp message) {
1010         MemberName memberName = memberToName(message.member());
1011
1012         LOG.info("{}: Received MemberUp: memberName: {}, address: {}", persistenceId(), memberName,
1013                 message.member().address());
1014
1015         memberUp(memberName, message.member().address());
1016     }
1017
1018     private void memberUp(final MemberName memberName, final Address address) {
1019         addPeerAddress(memberName, address);
1020         checkReady();
1021     }
1022
1023     private void memberWeaklyUp(final MemberWeaklyUp message) {
1024         MemberName memberName = memberToName(message.member());
1025
1026         LOG.info("{}: Received MemberWeaklyUp: memberName: {}, address: {}", persistenceId(), memberName,
1027                 message.member().address());
1028
1029         memberUp(memberName, message.member().address());
1030     }
1031
1032     private void addPeerAddress(final MemberName memberName, final Address address) {
1033         peerAddressResolver.addPeerAddress(memberName, address);
1034
1035         for (ShardInformation info : localShards.values()) {
1036             String shardName = info.getShardName();
1037             String peerId = getShardIdentifier(memberName, shardName).toString();
1038             info.updatePeerAddress(peerId, peerAddressResolver.getShardActorAddress(shardName, memberName), getSelf());
1039
1040             info.peerUp(memberName, peerId, getSelf());
1041         }
1042     }
1043
1044     private void memberReachable(final ClusterEvent.ReachableMember message) {
1045         MemberName memberName = memberToName(message.member());
1046         LOG.info("Received ReachableMember: memberName {}, address: {}", memberName, message.member().address());
1047
1048         addPeerAddress(memberName, message.member().address());
1049
1050         markMemberAvailable(memberName);
1051     }
1052
1053     private void memberUnreachable(final ClusterEvent.UnreachableMember message) {
1054         MemberName memberName = memberToName(message.member());
1055         LOG.info("Received UnreachableMember: memberName {}, address: {}", memberName, message.member().address());
1056
1057         markMemberUnavailable(memberName);
1058     }
1059
1060     private void markMemberUnavailable(final MemberName memberName) {
1061         for (ShardInformation info : localShards.values()) {
1062             String leaderId = info.getLeaderId();
1063             if (leaderId != null && ShardIdentifier.fromShardIdString(leaderId).getMemberName().equals(memberName)) {
1064                 LOG.debug("Marking Leader {} as unavailable.", leaderId);
1065                 info.setLeaderAvailable(false);
1066
1067                 primaryShardInfoCache.remove(info.getShardName());
1068
1069                 notifyShardAvailabilityCallbacks(info);
1070             }
1071
1072             info.peerDown(memberName, getShardIdentifier(memberName, info.getShardName()).toString(), getSelf());
1073         }
1074     }
1075
1076     private void markMemberAvailable(final MemberName memberName) {
1077         for (ShardInformation info : localShards.values()) {
1078             String leaderId = info.getLeaderId();
1079             if (leaderId != null && ShardIdentifier.fromShardIdString(leaderId).getMemberName().equals(memberName)) {
1080                 LOG.debug("Marking Leader {} as available.", leaderId);
1081                 info.setLeaderAvailable(true);
1082             }
1083
1084             info.peerUp(memberName, getShardIdentifier(memberName, info.getShardName()).toString(), getSelf());
1085         }
1086     }
1087
1088     private void onDatastoreContextFactory(final DatastoreContextFactory factory) {
1089         datastoreContextFactory = factory;
1090         for (ShardInformation info : localShards.values()) {
1091             info.setDatastoreContext(newShardDatastoreContext(info.getShardName()), getSelf());
1092         }
1093     }
1094
1095     private void onGetLocalShardIds() {
1096         final List<String> response = new ArrayList<>(localShards.size());
1097
1098         for (ShardInformation info : localShards.values()) {
1099             response.add(info.getShardId().toString());
1100         }
1101
1102         getSender().tell(new Status.Success(response), getSelf());
1103     }
1104
1105     private void onSwitchShardBehavior(final SwitchShardBehavior message) {
1106         final ShardIdentifier identifier = message.getShardId();
1107
1108         if (identifier != null) {
1109             final ShardInformation info = localShards.get(identifier.getShardName());
1110             if (info == null) {
1111                 getSender().tell(new Status.Failure(
1112                     new IllegalArgumentException("Shard " + identifier + " is not local")), getSelf());
1113                 return;
1114             }
1115
1116             switchShardBehavior(info, new SwitchBehavior(message.getNewState(), message.getTerm()));
1117         } else {
1118             for (ShardInformation info : localShards.values()) {
1119                 switchShardBehavior(info, new SwitchBehavior(message.getNewState(), message.getTerm()));
1120             }
1121         }
1122
1123         getSender().tell(new Status.Success(null), getSelf());
1124     }
1125
1126     private void switchShardBehavior(final ShardInformation info, final SwitchBehavior switchBehavior) {
1127         final ActorRef actor = info.getActor();
1128         if (actor != null) {
1129             actor.tell(switchBehavior, getSelf());
1130         } else {
1131             LOG.warn("Could not switch the behavior of shard {} to {} - shard is not yet available",
1132                 info.getShardName(), switchBehavior.getNewState());
1133         }
1134     }
1135
1136     /**
1137      * Notifies all the local shards of a change in the schema context.
1138      *
1139      * @param message the message to send
1140      */
1141     private void updateSchemaContext(final Object message) {
1142         schemaContext = ((UpdateSchemaContext) message).getEffectiveModelContext();
1143
1144         LOG.debug("Got updated SchemaContext: # of modules {}", schemaContext.getModules().size());
1145
1146         for (ShardInformation info : localShards.values()) {
1147             info.setSchemaContext(schemaContext);
1148
1149             if (info.getActor() == null) {
1150                 LOG.debug("Creating Shard {}", info.getShardId());
1151                 info.setActor(newShardActor(info));
1152                 // Update peer address for every existing peer memeber to avoid missing sending
1153                 // PeerAddressResolved and PeerUp to this shard while UpdateSchemaContext comes after MemberUp.
1154                 String shardName = info.getShardName();
1155                 for (MemberName memberName : peerAddressResolver.getPeerMembers()) {
1156                     String peerId = getShardIdentifier(memberName, shardName).toString() ;
1157                     String peerAddress = peerAddressResolver.getShardActorAddress(shardName, memberName);
1158                     info.updatePeerAddress(peerId, peerAddress, getSelf());
1159                     info.peerUp(memberName, peerId, getSelf());
1160                     LOG.debug("{}: updated peer {} on member {} with address {} on shard {} whose actor address is {}",
1161                             persistenceId(), peerId, memberName, peerAddress, info.getShardId(), info.getActor());
1162                 }
1163             } else {
1164                 info.getActor().tell(message, getSelf());
1165             }
1166         }
1167     }
1168
1169     @VisibleForTesting
1170     protected ClusterWrapper getCluster() {
1171         return cluster;
1172     }
1173
1174     @VisibleForTesting
1175     protected ActorRef newShardActor(final ShardInformation info) {
1176         return getContext().actorOf(info.newProps().withDispatcher(shardDispatcherPath),
1177                 info.getShardId().toString());
1178     }
1179
1180     private void findPrimary(final FindPrimary message) {
1181         LOG.debug("{}: In findPrimary: {}", persistenceId(), message);
1182
1183         final String shardName = message.getShardName();
1184         final boolean canReturnLocalShardState = !(message instanceof RemoteFindPrimary);
1185
1186         // First see if the there is a local replica for the shard
1187         final ShardInformation info = localShards.get(shardName);
1188         if (info != null && info.isActiveMember()) {
1189             sendResponse(info, message.isWaitUntilReady(), true, () -> {
1190                 String primaryPath = info.getSerializedLeaderActor();
1191                 Object found = canReturnLocalShardState && info.isLeader()
1192                         ? new LocalPrimaryShardFound(primaryPath, info.getLocalShardDataTree().get()) :
1193                             new RemotePrimaryShardFound(primaryPath, info.getLeaderVersion());
1194
1195                 LOG.debug("{}: Found primary for {}: {}", persistenceId(), shardName, found);
1196                 return found;
1197             });
1198
1199             return;
1200         }
1201
1202         final Collection<String> visitedAddresses;
1203         if (message instanceof RemoteFindPrimary) {
1204             visitedAddresses = ((RemoteFindPrimary)message).getVisitedAddresses();
1205         } else {
1206             visitedAddresses = new ArrayList<>(1);
1207         }
1208
1209         visitedAddresses.add(peerAddressResolver.getShardManagerActorPathBuilder(cluster.getSelfAddress()).toString());
1210
1211         for (String address: peerAddressResolver.getShardManagerPeerActorAddresses()) {
1212             if (visitedAddresses.contains(address)) {
1213                 continue;
1214             }
1215
1216             LOG.debug("{}: findPrimary for {} forwarding to remote ShardManager {}, visitedAddresses: {}",
1217                     persistenceId(), shardName, address, visitedAddresses);
1218
1219             getContext().actorSelection(address).forward(new RemoteFindPrimary(shardName,
1220                     message.isWaitUntilReady(), visitedAddresses), getContext());
1221             return;
1222         }
1223
1224         LOG.debug("{}: No shard found for {}", persistenceId(), shardName);
1225
1226         getSender().tell(new PrimaryNotFoundException(
1227                 String.format("No primary shard found for %s.", shardName)), getSelf());
1228     }
1229
1230     private void findPrimary(final String shardName, final FindPrimaryResponseHandler handler) {
1231         Timeout findPrimaryTimeout = new Timeout(datastoreContextFactory.getBaseDatastoreContext()
1232                 .getShardInitializationTimeout().duration().$times(2));
1233
1234         Future<Object> futureObj = ask(getSelf(), new FindPrimary(shardName, true), findPrimaryTimeout);
1235         futureObj.onComplete(new OnComplete<>() {
1236             @Override
1237             public void onComplete(final Throwable failure, final Object response) {
1238                 if (failure != null) {
1239                     handler.onFailure(failure);
1240                 } else {
1241                     if (response instanceof RemotePrimaryShardFound) {
1242                         handler.onRemotePrimaryShardFound((RemotePrimaryShardFound) response);
1243                     } else if (response instanceof LocalPrimaryShardFound) {
1244                         handler.onLocalPrimaryFound((LocalPrimaryShardFound) response);
1245                     } else {
1246                         handler.onUnknownResponse(response);
1247                     }
1248                 }
1249             }
1250         }, new Dispatchers(context().system().dispatchers()).getDispatcher(Dispatchers.DispatcherType.Client));
1251     }
1252
1253     /**
1254      * Construct the name of the shard actor given the name of the member on
1255      * which the shard resides and the name of the shard.
1256      *
1257      * @param memberName the member name
1258      * @param shardName the shard name
1259      * @return a b
1260      */
1261     private ShardIdentifier getShardIdentifier(final MemberName memberName, final String shardName) {
1262         return peerAddressResolver.getShardIdentifier(memberName, shardName);
1263     }
1264
1265     /**
1266      * Create shards that are local to the member on which the ShardManager runs.
1267      */
1268     private void createLocalShards() {
1269         MemberName memberName = this.cluster.getCurrentMemberName();
1270         Collection<String> memberShardNames = this.configuration.getMemberShardNames(memberName);
1271
1272         Map<String, DatastoreSnapshot.ShardSnapshot> shardSnapshots = new HashMap<>();
1273         if (restoreFromSnapshot != null) {
1274             for (DatastoreSnapshot.ShardSnapshot snapshot: restoreFromSnapshot.getShardSnapshots()) {
1275                 shardSnapshots.put(snapshot.getName(), snapshot);
1276             }
1277         }
1278
1279         // null out to GC
1280         restoreFromSnapshot = null;
1281
1282         for (String shardName : memberShardNames) {
1283             ShardIdentifier shardId = getShardIdentifier(memberName, shardName);
1284
1285             LOG.debug("{}: Creating local shard: {}", persistenceId(), shardId);
1286
1287             Map<String, String> peerAddresses = getPeerAddresses(shardName);
1288             localShards.put(shardName, createShardInfoFor(shardName, shardId, peerAddresses,
1289                     newShardDatastoreContext(shardName), shardSnapshots));
1290         }
1291     }
1292
1293     @VisibleForTesting
1294     ShardInformation createShardInfoFor(final String shardName, final ShardIdentifier shardId,
1295                                         final Map<String, String> peerAddresses,
1296                                         final DatastoreContext datastoreContext,
1297                                         final Map<String, DatastoreSnapshot.ShardSnapshot> shardSnapshots) {
1298         return new ShardInformation(shardName, shardId, peerAddresses,
1299                 datastoreContext, Shard.builder().restoreFromSnapshot(shardSnapshots.get(shardName)),
1300                 peerAddressResolver);
1301     }
1302
1303     /**
1304      * Given the name of the shard find the addresses of all it's peers.
1305      *
1306      * @param shardName the shard name
1307      */
1308     Map<String, String> getPeerAddresses(final String shardName) {
1309         final Collection<MemberName> members = configuration.getMembersFromShardName(shardName);
1310         return getPeerAddresses(shardName, members);
1311     }
1312
1313     private Map<String, String> getPeerAddresses(final String shardName, final Collection<MemberName> members) {
1314         Map<String, String> peerAddresses = new HashMap<>();
1315         MemberName currentMemberName = this.cluster.getCurrentMemberName();
1316
1317         for (MemberName memberName : members) {
1318             if (!currentMemberName.equals(memberName)) {
1319                 ShardIdentifier shardId = getShardIdentifier(memberName, shardName);
1320                 String address = peerAddressResolver.getShardActorAddress(shardName, memberName);
1321                 peerAddresses.put(shardId.toString(), address);
1322             }
1323         }
1324         return peerAddresses;
1325     }
1326
1327     @Override
1328     public SupervisorStrategy supervisorStrategy() {
1329
1330         return new OneForOneStrategy(10, FiniteDuration.create(1, TimeUnit.MINUTES),
1331                 (Function<Throwable, Directive>) t -> {
1332                     LOG.warn("Supervisor Strategy caught unexpected exception - resuming", t);
1333                     return SupervisorStrategy.resume();
1334                 });
1335     }
1336
1337     @Override
1338     public String persistenceId() {
1339         return persistenceId;
1340     }
1341
1342     @VisibleForTesting
1343     ShardManagerInfoMBean getMBean() {
1344         return shardManagerMBean;
1345     }
1346
1347     private boolean isShardReplicaOperationInProgress(final String shardName, final ActorRef sender) {
1348         if (shardReplicaOperationsInProgress.contains(shardName)) {
1349             LOG.debug("{}: A shard replica operation for {} is already in progress", persistenceId(), shardName);
1350             sender.tell(new Status.Failure(new IllegalStateException(
1351                 String.format("A shard replica operation for %s is already in progress", shardName))), getSelf());
1352             return true;
1353         }
1354
1355         return false;
1356     }
1357
1358     private void onAddPrefixShardReplica(final AddPrefixShardReplica message) {
1359         LOG.debug("{}: onAddPrefixShardReplica: {}", persistenceId(), message);
1360
1361         final ShardIdentifier shardId = getShardIdentifier(cluster.getCurrentMemberName(),
1362                 ClusterUtils.getCleanShardName(message.getShardPrefix()));
1363         final String shardName = shardId.getShardName();
1364
1365         // Create the localShard
1366         if (schemaContext == null) {
1367             LOG.debug("{}: No SchemaContext is available in order to create a local shard instance for {}",
1368                 persistenceId(), shardName);
1369             getSender().tell(new Status.Failure(new IllegalStateException(
1370                 "No SchemaContext is available in order to create a local shard instance for " + shardName)),
1371                 getSelf());
1372             return;
1373         }
1374
1375         findPrimary(shardName, new AutoFindPrimaryFailureResponseHandler(getSender(), shardName, persistenceId(),
1376                 getSelf()) {
1377             @Override
1378             public void onRemotePrimaryShardFound(final RemotePrimaryShardFound response) {
1379                 final RunnableMessage runnable = (RunnableMessage) () -> addPrefixShard(getShardName(),
1380                         message.getShardPrefix(), response, getSender());
1381                 if (!isPreviousShardActorStopInProgress(getShardName(), runnable)) {
1382                     getSelf().tell(runnable, getTargetActor());
1383                 }
1384             }
1385
1386             @Override
1387             public void onLocalPrimaryFound(final LocalPrimaryShardFound message) {
1388                 sendLocalReplicaAlreadyExistsReply(getShardName(), getTargetActor());
1389             }
1390         });
1391     }
1392
1393     private void onAddShardReplica(final AddShardReplica shardReplicaMsg) {
1394         final String shardName = shardReplicaMsg.getShardName();
1395
1396         LOG.debug("{}: onAddShardReplica: {}", persistenceId(), shardReplicaMsg);
1397
1398         // verify the shard with the specified name is present in the cluster configuration
1399         if (!this.configuration.isShardConfigured(shardName)) {
1400             LOG.debug("{}: No module configuration exists for shard {}", persistenceId(), shardName);
1401             getSender().tell(new Status.Failure(new IllegalArgumentException(
1402                 "No module configuration exists for shard " + shardName)), getSelf());
1403             return;
1404         }
1405
1406         // Create the localShard
1407         if (schemaContext == null) {
1408             LOG.debug("{}: No SchemaContext is available in order to create a local shard instance for {}",
1409                 persistenceId(), shardName);
1410             getSender().tell(new Status.Failure(new IllegalStateException(
1411                 "No SchemaContext is available in order to create a local shard instance for " + shardName)),
1412                 getSelf());
1413             return;
1414         }
1415
1416         findPrimary(shardName, new AutoFindPrimaryFailureResponseHandler(getSender(), shardName, persistenceId(),
1417                 getSelf()) {
1418             @Override
1419             public void onRemotePrimaryShardFound(final RemotePrimaryShardFound response) {
1420                 final RunnableMessage runnable = (RunnableMessage) () ->
1421                     addShard(getShardName(), response, getSender());
1422                 if (!isPreviousShardActorStopInProgress(getShardName(), runnable)) {
1423                     getSelf().tell(runnable, getTargetActor());
1424                 }
1425             }
1426
1427             @Override
1428             public void onLocalPrimaryFound(final LocalPrimaryShardFound message) {
1429                 sendLocalReplicaAlreadyExistsReply(getShardName(), getTargetActor());
1430             }
1431         });
1432     }
1433
1434     @SuppressFBWarnings(value = "UPM_UNCALLED_PRIVATE_METHOD",
1435             justification = "https://github.com/spotbugs/spotbugs/issues/811")
1436     private void sendLocalReplicaAlreadyExistsReply(final String shardName, final ActorRef sender) {
1437         LOG.debug("{}: Local shard {} already exists", persistenceId(), shardName);
1438         sender.tell(new Status.Failure(new AlreadyExistsException(
1439             String.format("Local shard %s already exists", shardName))), getSelf());
1440     }
1441
1442     @SuppressFBWarnings(value = "UPM_UNCALLED_PRIVATE_METHOD",
1443             justification = "https://github.com/spotbugs/spotbugs/issues/811")
1444     private void addPrefixShard(final String shardName, final YangInstanceIdentifier shardPrefix,
1445                                 final RemotePrimaryShardFound response, final ActorRef sender) {
1446         if (isShardReplicaOperationInProgress(shardName, sender)) {
1447             return;
1448         }
1449
1450         shardReplicaOperationsInProgress.add(shardName);
1451
1452         final ShardInformation shardInfo;
1453         final boolean removeShardOnFailure;
1454         ShardInformation existingShardInfo = localShards.get(shardName);
1455         if (existingShardInfo == null) {
1456             removeShardOnFailure = true;
1457             ShardIdentifier shardId = getShardIdentifier(cluster.getCurrentMemberName(), shardName);
1458
1459             final Builder builder = newShardDatastoreContextBuilder(shardName);
1460             builder.storeRoot(shardPrefix).customRaftPolicyImplementation(DisableElectionsRaftPolicy.class.getName());
1461
1462             DatastoreContext datastoreContext = builder.build();
1463
1464             shardInfo = new ShardInformation(shardName, shardId, getPeerAddresses(shardName), datastoreContext,
1465                     Shard.builder(), peerAddressResolver);
1466             shardInfo.setActiveMember(false);
1467             shardInfo.setSchemaContext(schemaContext);
1468             localShards.put(shardName, shardInfo);
1469             shardInfo.setActor(newShardActor(shardInfo));
1470         } else {
1471             removeShardOnFailure = false;
1472             shardInfo = existingShardInfo;
1473         }
1474
1475         execAddShard(shardName, shardInfo, response, removeShardOnFailure, sender);
1476     }
1477
1478     @SuppressFBWarnings(value = "UPM_UNCALLED_PRIVATE_METHOD",
1479             justification = "https://github.com/spotbugs/spotbugs/issues/811")
1480     private void addShard(final String shardName, final RemotePrimaryShardFound response, final ActorRef sender) {
1481         if (isShardReplicaOperationInProgress(shardName, sender)) {
1482             return;
1483         }
1484
1485         shardReplicaOperationsInProgress.add(shardName);
1486
1487         final ShardInformation shardInfo;
1488         final boolean removeShardOnFailure;
1489         ShardInformation existingShardInfo = localShards.get(shardName);
1490         if (existingShardInfo == null) {
1491             removeShardOnFailure = true;
1492             ShardIdentifier shardId = getShardIdentifier(cluster.getCurrentMemberName(), shardName);
1493
1494             DatastoreContext datastoreContext = newShardDatastoreContextBuilder(shardName)
1495                     .customRaftPolicyImplementation(DisableElectionsRaftPolicy.class.getName()).build();
1496
1497             shardInfo = new ShardInformation(shardName, shardId, getPeerAddresses(shardName), datastoreContext,
1498                     Shard.builder(), peerAddressResolver);
1499             shardInfo.setActiveMember(false);
1500             shardInfo.setSchemaContext(schemaContext);
1501             localShards.put(shardName, shardInfo);
1502             shardInfo.setActor(newShardActor(shardInfo));
1503         } else {
1504             removeShardOnFailure = false;
1505             shardInfo = existingShardInfo;
1506         }
1507
1508         execAddShard(shardName, shardInfo, response, removeShardOnFailure, sender);
1509     }
1510
1511     private void execAddShard(final String shardName,
1512                               final ShardInformation shardInfo,
1513                               final RemotePrimaryShardFound response,
1514                               final boolean removeShardOnFailure,
1515                               final ActorRef sender) {
1516
1517         final String localShardAddress =
1518                 peerAddressResolver.getShardActorAddress(shardName, cluster.getCurrentMemberName());
1519
1520         //inform ShardLeader to add this shard as a replica by sending an AddServer message
1521         LOG.debug("{}: Sending AddServer message to peer {} for shard {}", persistenceId(),
1522                 response.getPrimaryPath(), shardInfo.getShardId());
1523
1524         final Timeout addServerTimeout = new Timeout(shardInfo.getDatastoreContext()
1525                 .getShardLeaderElectionTimeout().duration());
1526         final Future<Object> futureObj = ask(getContext().actorSelection(response.getPrimaryPath()),
1527                 new AddServer(shardInfo.getShardId().toString(), localShardAddress, true), addServerTimeout);
1528
1529         futureObj.onComplete(new OnComplete<>() {
1530             @Override
1531             public void onComplete(final Throwable failure, final Object addServerResponse) {
1532                 if (failure != null) {
1533                     LOG.debug("{}: AddServer request to {} for {} failed", persistenceId(),
1534                             response.getPrimaryPath(), shardName, failure);
1535
1536                     final String msg = String.format("AddServer request to leader %s for shard %s failed",
1537                             response.getPrimaryPath(), shardName);
1538                     self().tell(new ForwardedAddServerFailure(shardName, msg, failure, removeShardOnFailure), sender);
1539                 } else {
1540                     self().tell(new ForwardedAddServerReply(shardInfo, (AddServerReply)addServerResponse,
1541                             response.getPrimaryPath(), removeShardOnFailure), sender);
1542                 }
1543             }
1544         }, new Dispatchers(context().system().dispatchers()).getDispatcher(Dispatchers.DispatcherType.Client));
1545     }
1546
1547     private void onAddServerFailure(final String shardName, final String message, final Throwable failure,
1548             final ActorRef sender, final boolean removeShardOnFailure) {
1549         shardReplicaOperationsInProgress.remove(shardName);
1550
1551         if (removeShardOnFailure) {
1552             ShardInformation shardInfo = localShards.remove(shardName);
1553             if (shardInfo.getActor() != null) {
1554                 shardInfo.getActor().tell(PoisonPill.getInstance(), getSelf());
1555             }
1556         }
1557
1558         sender.tell(new Status.Failure(message == null ? failure :
1559             new RuntimeException(message, failure)), getSelf());
1560     }
1561
1562     private void onAddServerReply(final ShardInformation shardInfo, final AddServerReply replyMsg,
1563             final ActorRef sender, final String leaderPath, final boolean removeShardOnFailure) {
1564         String shardName = shardInfo.getShardName();
1565         shardReplicaOperationsInProgress.remove(shardName);
1566
1567         LOG.debug("{}: Received {} for shard {} from leader {}", persistenceId(), replyMsg, shardName, leaderPath);
1568
1569         if (replyMsg.getStatus() == ServerChangeStatus.OK) {
1570             LOG.debug("{}: Leader shard successfully added the replica shard {}", persistenceId(), shardName);
1571
1572             // Make the local shard voting capable
1573             shardInfo.setDatastoreContext(newShardDatastoreContext(shardName), getSelf());
1574             shardInfo.setActiveMember(true);
1575             persistShardList();
1576
1577             sender.tell(new Status.Success(null), getSelf());
1578         } else if (replyMsg.getStatus() == ServerChangeStatus.ALREADY_EXISTS) {
1579             sendLocalReplicaAlreadyExistsReply(shardName, sender);
1580         } else {
1581             LOG.warn("{}: Leader failed to add shard replica {} with status {}",
1582                     persistenceId(), shardName, replyMsg.getStatus());
1583
1584             Exception failure = getServerChangeException(AddServer.class, replyMsg.getStatus(), leaderPath,
1585                     shardInfo.getShardId());
1586
1587             onAddServerFailure(shardName, null, failure, sender, removeShardOnFailure);
1588         }
1589     }
1590
1591     private static Exception getServerChangeException(final Class<?> serverChange,
1592             final ServerChangeStatus serverChangeStatus, final String leaderPath, final ShardIdentifier shardId) {
1593         switch (serverChangeStatus) {
1594             case TIMEOUT:
1595                 return new TimeoutException(String.format(
1596                         "The shard leader %s timed out trying to replicate the initial data to the new shard %s."
1597                         + "Possible causes - there was a problem replicating the data or shard leadership changed "
1598                         + "while replicating the shard data", leaderPath, shardId.getShardName()));
1599             case NO_LEADER:
1600                 return new NoShardLeaderException(shardId);
1601             case NOT_SUPPORTED:
1602                 return new UnsupportedOperationException(String.format("%s request is not supported for shard %s",
1603                         serverChange.getSimpleName(), shardId.getShardName()));
1604             default :
1605                 return new RuntimeException(String.format("%s request to leader %s for shard %s failed with status %s",
1606                         serverChange.getSimpleName(), leaderPath, shardId.getShardName(), serverChangeStatus));
1607         }
1608     }
1609
1610     private void onRemoveShardReplica(final RemoveShardReplica shardReplicaMsg) {
1611         LOG.debug("{}: onRemoveShardReplica: {}", persistenceId(), shardReplicaMsg);
1612
1613         findPrimary(shardReplicaMsg.getShardName(), new AutoFindPrimaryFailureResponseHandler(getSender(),
1614                 shardReplicaMsg.getShardName(), persistenceId(), getSelf()) {
1615             @Override
1616             public void onRemotePrimaryShardFound(final RemotePrimaryShardFound response) {
1617                 doRemoveShardReplicaAsync(response.getPrimaryPath());
1618             }
1619
1620             @Override
1621             public void onLocalPrimaryFound(final LocalPrimaryShardFound response) {
1622                 doRemoveShardReplicaAsync(response.getPrimaryPath());
1623             }
1624
1625             private void doRemoveShardReplicaAsync(final String primaryPath) {
1626                 getSelf().tell((RunnableMessage) () -> removeShardReplica(shardReplicaMsg, getShardName(),
1627                         primaryPath, getSender()), getTargetActor());
1628             }
1629         });
1630     }
1631
1632     private void onRemovePrefixShardReplica(final RemovePrefixShardReplica message) {
1633         LOG.debug("{}: onRemovePrefixShardReplica: {}", persistenceId(), message);
1634
1635         final ShardIdentifier shardId = getShardIdentifier(cluster.getCurrentMemberName(),
1636                 ClusterUtils.getCleanShardName(message.getShardPrefix()));
1637         final String shardName = shardId.getShardName();
1638
1639         findPrimary(shardName, new AutoFindPrimaryFailureResponseHandler(getSender(),
1640                 shardName, persistenceId(), getSelf()) {
1641             @Override
1642             public void onRemotePrimaryShardFound(final RemotePrimaryShardFound response) {
1643                 doRemoveShardReplicaAsync(response.getPrimaryPath());
1644             }
1645
1646             @Override
1647             public void onLocalPrimaryFound(final LocalPrimaryShardFound response) {
1648                 doRemoveShardReplicaAsync(response.getPrimaryPath());
1649             }
1650
1651             private void doRemoveShardReplicaAsync(final String primaryPath) {
1652                 getSelf().tell((RunnableMessage) () -> removePrefixShardReplica(message, getShardName(),
1653                         primaryPath, getSender()), getTargetActor());
1654             }
1655         });
1656     }
1657
1658     private void persistShardList() {
1659         List<String> shardList = new ArrayList<>(localShards.keySet());
1660         for (ShardInformation shardInfo : localShards.values()) {
1661             if (!shardInfo.isActiveMember()) {
1662                 shardList.remove(shardInfo.getShardName());
1663             }
1664         }
1665         LOG.debug("{}: persisting the shard list {}", persistenceId(), shardList);
1666         saveSnapshot(updateShardManagerSnapshot(shardList, configuration.getAllPrefixShardConfigurations()));
1667     }
1668
1669     private ShardManagerSnapshot updateShardManagerSnapshot(
1670             final List<String> shardList,
1671             final Map<DOMDataTreeIdentifier, PrefixShardConfiguration> allPrefixShardConfigurations) {
1672         currentSnapshot = new ShardManagerSnapshot(shardList, allPrefixShardConfigurations);
1673         return currentSnapshot;
1674     }
1675
1676     private void applyShardManagerSnapshot(final ShardManagerSnapshot snapshot) {
1677         currentSnapshot = snapshot;
1678
1679         LOG.debug("{}: onSnapshotOffer: {}", persistenceId(), currentSnapshot);
1680
1681         final MemberName currentMember = cluster.getCurrentMemberName();
1682         Set<String> configuredShardList =
1683             new HashSet<>(configuration.getMemberShardNames(currentMember));
1684         for (String shard : currentSnapshot.getShardList()) {
1685             if (!configuredShardList.contains(shard)) {
1686                 // add the current member as a replica for the shard
1687                 LOG.debug("{}: adding shard {}", persistenceId(), shard);
1688                 configuration.addMemberReplicaForShard(shard, currentMember);
1689             } else {
1690                 configuredShardList.remove(shard);
1691             }
1692         }
1693         for (String shard : configuredShardList) {
1694             // remove the member as a replica for the shard
1695             LOG.debug("{}: removing shard {}", persistenceId(), shard);
1696             configuration.removeMemberReplicaForShard(shard, currentMember);
1697         }
1698     }
1699
1700     private void onSaveSnapshotSuccess(final SaveSnapshotSuccess successMessage) {
1701         LOG.debug("{} saved ShardManager snapshot successfully. Deleting the prev snapshot if available",
1702             persistenceId());
1703         deleteSnapshots(new SnapshotSelectionCriteria(scala.Long.MaxValue(), successMessage.metadata().timestamp() - 1,
1704             0, 0));
1705     }
1706
1707     private void onChangeShardServersVotingStatus(final ChangeShardMembersVotingStatus changeMembersVotingStatus) {
1708         LOG.debug("{}: onChangeShardServersVotingStatus: {}", persistenceId(), changeMembersVotingStatus);
1709
1710         String shardName = changeMembersVotingStatus.getShardName();
1711         Map<String, Boolean> serverVotingStatusMap = new HashMap<>();
1712         for (Entry<String, Boolean> e: changeMembersVotingStatus.getMeberVotingStatusMap().entrySet()) {
1713             serverVotingStatusMap.put(getShardIdentifier(MemberName.forName(e.getKey()), shardName).toString(),
1714                     e.getValue());
1715         }
1716
1717         ChangeServersVotingStatus changeServersVotingStatus = new ChangeServersVotingStatus(serverVotingStatusMap);
1718
1719         findLocalShard(shardName, getSender(),
1720             localShardFound -> changeShardMembersVotingStatus(changeServersVotingStatus, shardName,
1721             localShardFound.getPath(), getSender()));
1722     }
1723
1724     private void onFlipShardMembersVotingStatus(final FlipShardMembersVotingStatus flipMembersVotingStatus) {
1725         LOG.debug("{}: onFlipShardMembersVotingStatus: {}", persistenceId(), flipMembersVotingStatus);
1726
1727         ActorRef sender = getSender();
1728         final String shardName = flipMembersVotingStatus.getShardName();
1729         findLocalShard(shardName, sender, localShardFound -> {
1730             Future<Object> future = ask(localShardFound.getPath(), GetOnDemandRaftState.INSTANCE,
1731                     Timeout.apply(30, TimeUnit.SECONDS));
1732
1733             future.onComplete(new OnComplete<>() {
1734                 @Override
1735                 public void onComplete(final Throwable failure, final Object response) {
1736                     if (failure != null) {
1737                         sender.tell(new Status.Failure(new RuntimeException(
1738                                 String.format("Failed to access local shard %s", shardName), failure)), self());
1739                         return;
1740                     }
1741
1742                     OnDemandRaftState raftState = (OnDemandRaftState) response;
1743                     Map<String, Boolean> serverVotingStatusMap = new HashMap<>();
1744                     for (Entry<String, Boolean> e: raftState.getPeerVotingStates().entrySet()) {
1745                         serverVotingStatusMap.put(e.getKey(), !e.getValue());
1746                     }
1747
1748                     serverVotingStatusMap.put(getShardIdentifier(cluster.getCurrentMemberName(), shardName)
1749                             .toString(), !raftState.isVoting());
1750
1751                     changeShardMembersVotingStatus(new ChangeServersVotingStatus(serverVotingStatusMap),
1752                             shardName, localShardFound.getPath(), sender);
1753                 }
1754             }, new Dispatchers(context().system().dispatchers()).getDispatcher(Dispatchers.DispatcherType.Client));
1755         });
1756
1757     }
1758
1759     private void findLocalShard(final FindLocalShard message) {
1760         LOG.debug("{}: findLocalShard : {}", persistenceId(), message.getShardName());
1761
1762         final ShardInformation shardInformation = localShards.get(message.getShardName());
1763
1764         if (shardInformation == null) {
1765             LOG.debug("{}: Local shard {} not found - shards present: {}",
1766                     persistenceId(), message.getShardName(), localShards.keySet());
1767
1768             getSender().tell(new LocalShardNotFound(message.getShardName()), getSelf());
1769             return;
1770         }
1771
1772         sendResponse(shardInformation, message.isWaitUntilInitialized(), false,
1773             () -> new LocalShardFound(shardInformation.getActor()));
1774     }
1775
1776     private void findLocalShard(final String shardName, final ActorRef sender,
1777             final Consumer<LocalShardFound> onLocalShardFound) {
1778         Timeout findLocalTimeout = new Timeout(datastoreContextFactory.getBaseDatastoreContext()
1779                 .getShardInitializationTimeout().duration().$times(2));
1780
1781         Future<Object> futureObj = ask(getSelf(), new FindLocalShard(shardName, true), findLocalTimeout);
1782         futureObj.onComplete(new OnComplete<>() {
1783             @Override
1784             public void onComplete(final Throwable failure, final Object response) {
1785                 if (failure != null) {
1786                     LOG.debug("{}: Received failure from FindLocalShard for shard {}", persistenceId, shardName,
1787                             failure);
1788                     sender.tell(new Status.Failure(new RuntimeException(
1789                             String.format("Failed to find local shard %s", shardName), failure)), self());
1790                 } else {
1791                     if (response instanceof LocalShardFound) {
1792                         getSelf().tell((RunnableMessage) () -> onLocalShardFound.accept((LocalShardFound) response),
1793                                 sender);
1794                     } else if (response instanceof LocalShardNotFound) {
1795                         LOG.debug("{}: Local shard {} does not exist", persistenceId, shardName);
1796                         sender.tell(new Status.Failure(new IllegalArgumentException(
1797                             String.format("Local shard %s does not exist", shardName))), self());
1798                     } else {
1799                         LOG.debug("{}: Failed to find local shard {}: received response: {}", persistenceId, shardName,
1800                             response);
1801                         sender.tell(new Status.Failure(response instanceof Throwable ? (Throwable) response
1802                                 : new RuntimeException(
1803                                     String.format("Failed to find local shard %s: received response: %s", shardName,
1804                                         response))), self());
1805                     }
1806                 }
1807             }
1808         }, new Dispatchers(context().system().dispatchers()).getDispatcher(Dispatchers.DispatcherType.Client));
1809     }
1810
1811     private void changeShardMembersVotingStatus(final ChangeServersVotingStatus changeServersVotingStatus,
1812             final String shardName, final ActorRef shardActorRef, final ActorRef sender) {
1813         if (isShardReplicaOperationInProgress(shardName, sender)) {
1814             return;
1815         }
1816
1817         shardReplicaOperationsInProgress.add(shardName);
1818
1819         DatastoreContext datastoreContext = newShardDatastoreContextBuilder(shardName).build();
1820         final ShardIdentifier shardId = getShardIdentifier(cluster.getCurrentMemberName(), shardName);
1821
1822         LOG.debug("{}: Sending ChangeServersVotingStatus message {} to local shard {}", persistenceId(),
1823                 changeServersVotingStatus, shardActorRef.path());
1824
1825         Timeout timeout = new Timeout(datastoreContext.getShardLeaderElectionTimeout().duration().$times(2));
1826         Future<Object> futureObj = ask(shardActorRef, changeServersVotingStatus, timeout);
1827
1828         futureObj.onComplete(new OnComplete<>() {
1829             @Override
1830             public void onComplete(final Throwable failure, final Object response) {
1831                 shardReplicaOperationsInProgress.remove(shardName);
1832                 if (failure != null) {
1833                     LOG.debug("{}: ChangeServersVotingStatus request to local shard {} failed", persistenceId(),
1834                         shardActorRef.path(), failure);
1835                     sender.tell(new Status.Failure(new RuntimeException(
1836                         String.format("ChangeServersVotingStatus request to local shard %s failed",
1837                             shardActorRef.path()), failure)), self());
1838                 } else {
1839                     LOG.debug("{}: Received {} from local shard {}", persistenceId(), response, shardActorRef.path());
1840
1841                     ServerChangeReply replyMsg = (ServerChangeReply) response;
1842                     if (replyMsg.getStatus() == ServerChangeStatus.OK) {
1843                         LOG.debug("{}: ChangeServersVotingStatus succeeded for shard {}", persistenceId(), shardName);
1844                         sender.tell(new Status.Success(null), getSelf());
1845                     } else if (replyMsg.getStatus() == ServerChangeStatus.INVALID_REQUEST) {
1846                         sender.tell(new Status.Failure(new IllegalArgumentException(String.format(
1847                                 "The requested voting state change for shard %s is invalid. At least one member "
1848                                 + "must be voting", shardId.getShardName()))), getSelf());
1849                     } else {
1850                         LOG.warn("{}: ChangeServersVotingStatus failed for shard {} with status {}",
1851                                 persistenceId(), shardName, replyMsg.getStatus());
1852
1853                         Exception error = getServerChangeException(ChangeServersVotingStatus.class,
1854                                 replyMsg.getStatus(), shardActorRef.path().toString(), shardId);
1855                         sender.tell(new Status.Failure(error), getSelf());
1856                     }
1857                 }
1858             }
1859         }, new Dispatchers(context().system().dispatchers()).getDispatcher(Dispatchers.DispatcherType.Client));
1860     }
1861
1862     private static final class ForwardedAddServerReply {
1863         ShardInformation shardInfo;
1864         AddServerReply addServerReply;
1865         String leaderPath;
1866         boolean removeShardOnFailure;
1867
1868         ForwardedAddServerReply(final ShardInformation shardInfo, final AddServerReply addServerReply,
1869             final String leaderPath, final boolean removeShardOnFailure) {
1870             this.shardInfo = shardInfo;
1871             this.addServerReply = addServerReply;
1872             this.leaderPath = leaderPath;
1873             this.removeShardOnFailure = removeShardOnFailure;
1874         }
1875     }
1876
1877     private static final class ForwardedAddServerFailure {
1878         String shardName;
1879         String failureMessage;
1880         Throwable failure;
1881         boolean removeShardOnFailure;
1882
1883         ForwardedAddServerFailure(final String shardName, final String failureMessage, final Throwable failure,
1884                 final boolean removeShardOnFailure) {
1885             this.shardName = shardName;
1886             this.failureMessage = failureMessage;
1887             this.failure = failure;
1888             this.removeShardOnFailure = removeShardOnFailure;
1889         }
1890     }
1891
1892     static class OnShardInitialized {
1893         private final Runnable replyRunnable;
1894         private Cancellable timeoutSchedule;
1895
1896         OnShardInitialized(final Runnable replyRunnable) {
1897             this.replyRunnable = replyRunnable;
1898         }
1899
1900         Runnable getReplyRunnable() {
1901             return replyRunnable;
1902         }
1903
1904         Cancellable getTimeoutSchedule() {
1905             return timeoutSchedule;
1906         }
1907
1908         void setTimeoutSchedule(final Cancellable timeoutSchedule) {
1909             this.timeoutSchedule = timeoutSchedule;
1910         }
1911     }
1912
1913     static class OnShardReady extends OnShardInitialized {
1914         OnShardReady(final Runnable replyRunnable) {
1915             super(replyRunnable);
1916         }
1917     }
1918
1919     private interface RunnableMessage extends Runnable {
1920     }
1921
1922     /**
1923      * The FindPrimaryResponseHandler provides specific callback methods which are invoked when a response to the
1924      * a remote or local find primary message is processed.
1925      */
1926     private interface FindPrimaryResponseHandler {
1927         /**
1928          * Invoked when a Failure message is received as a response.
1929          *
1930          * @param failure the failure exception
1931          */
1932         void onFailure(Throwable failure);
1933
1934         /**
1935          * Invoked when a RemotePrimaryShardFound response is received.
1936          *
1937          * @param response the response
1938          */
1939         void onRemotePrimaryShardFound(RemotePrimaryShardFound response);
1940
1941         /**
1942          * Invoked when a LocalPrimaryShardFound response is received.
1943          *
1944          * @param response the response
1945          */
1946         void onLocalPrimaryFound(LocalPrimaryShardFound response);
1947
1948         /**
1949          * Invoked when an unknown response is received. This is another type of failure.
1950          *
1951          * @param response the response
1952          */
1953         void onUnknownResponse(Object response);
1954     }
1955
1956     /**
1957      * The AutoFindPrimaryFailureResponseHandler automatically processes Failure responses when finding a primary
1958      * replica and sends a wrapped Failure response to some targetActor.
1959      */
1960     private abstract static class AutoFindPrimaryFailureResponseHandler implements FindPrimaryResponseHandler {
1961         private final ActorRef targetActor;
1962         private final String shardName;
1963         private final String persistenceId;
1964         private final ActorRef shardManagerActor;
1965
1966         /**
1967          * Constructs an instance.
1968          *
1969          * @param targetActor The actor to whom the Failure response should be sent when a FindPrimary failure occurs
1970          * @param shardName The name of the shard for which the primary replica had to be found
1971          * @param persistenceId The persistenceId for the ShardManager
1972          * @param shardManagerActor The ShardManager actor which triggered the call to FindPrimary
1973          */
1974         protected AutoFindPrimaryFailureResponseHandler(final ActorRef targetActor, final String shardName,
1975                 final String persistenceId, final ActorRef shardManagerActor) {
1976             this.targetActor = requireNonNull(targetActor);
1977             this.shardName = requireNonNull(shardName);
1978             this.persistenceId = requireNonNull(persistenceId);
1979             this.shardManagerActor = requireNonNull(shardManagerActor);
1980         }
1981
1982         public ActorRef getTargetActor() {
1983             return targetActor;
1984         }
1985
1986         public String getShardName() {
1987             return shardName;
1988         }
1989
1990         @Override
1991         public void onFailure(final Throwable failure) {
1992             LOG.debug("{}: Received failure from FindPrimary for shard {}", persistenceId, shardName, failure);
1993             targetActor.tell(new Status.Failure(new RuntimeException(
1994                     String.format("Failed to find leader for shard %s", shardName), failure)), shardManagerActor);
1995         }
1996
1997         @Override
1998         public void onUnknownResponse(final Object response) {
1999             LOG.debug("{}: Failed to find leader for shard {}: received response: {}", persistenceId, shardName,
2000                 response);
2001             targetActor.tell(new Status.Failure(response instanceof Throwable ? (Throwable) response
2002                     : new RuntimeException(String.format("Failed to find leader for shard %s: received response: %s",
2003                         shardName, response))), shardManagerActor);
2004         }
2005     }
2006
2007     /**
2008      * The WrappedShardResponse class wraps a response from a Shard.
2009      */
2010     private static final class WrappedShardResponse {
2011         private final ShardIdentifier shardId;
2012         private final Object response;
2013         private final String leaderPath;
2014
2015         WrappedShardResponse(final ShardIdentifier shardId, final Object response, final String leaderPath) {
2016             this.shardId = shardId;
2017             this.response = response;
2018             this.leaderPath = leaderPath;
2019         }
2020
2021         ShardIdentifier getShardId() {
2022             return shardId;
2023         }
2024
2025         Object getResponse() {
2026             return response;
2027         }
2028
2029         String getLeaderPath() {
2030             return leaderPath;
2031         }
2032     }
2033
2034     private static final class ShardNotInitializedTimeout {
2035         private final ActorRef sender;
2036         private final ShardInformation shardInfo;
2037         private final OnShardInitialized onShardInitialized;
2038
2039         ShardNotInitializedTimeout(final ShardInformation shardInfo, final OnShardInitialized onShardInitialized,
2040             final ActorRef sender) {
2041             this.sender = sender;
2042             this.shardInfo = shardInfo;
2043             this.onShardInitialized = onShardInitialized;
2044         }
2045
2046         ActorRef getSender() {
2047             return sender;
2048         }
2049
2050         ShardInformation getShardInfo() {
2051             return shardInfo;
2052         }
2053
2054         OnShardInitialized getOnShardInitialized() {
2055             return onShardInitialized;
2056         }
2057     }
2058 }
2059
2060
2061