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