opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/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;
  10
  11 import akka.actor.ActorPath;
  12 import akka.actor.ActorRef;
  13 import akka.actor.Address;
  14 import akka.actor.Cancellable;
  15 import akka.actor.OneForOneStrategy;
  16 import akka.actor.Props;
  17 import akka.actor.SupervisorStrategy;
  18 import akka.cluster.ClusterEvent;
  19 import akka.japi.Creator;
  20 import akka.japi.Function;
  21 import akka.japi.Procedure;
  22 import akka.persistence.RecoveryCompleted;
  23 import akka.persistence.RecoveryFailure;
  24 import akka.serialization.Serialization;
  25 import com.google.common.annotations.VisibleForTesting;
  26 import com.google.common.base.Objects;
  27 import com.google.common.base.Optional;
  28 import com.google.common.base.Preconditions;
  29 import com.google.common.base.Strings;
  30 import com.google.common.base.Supplier;
  31 import com.google.common.collect.ImmutableSet;
  32 import com.google.common.collect.Sets;
  33 import java.io.Serializable;
  34 import java.util.ArrayList;
  35 import java.util.Collection;
  36 import java.util.Collections;
  37 import java.util.HashMap;
  38 import java.util.HashSet;
  39 import java.util.Iterator;
  40 import java.util.List;
  41 import java.util.Map;
  42 import java.util.Set;
  43 import java.util.concurrent.CountDownLatch;
  44 import org.opendaylight.controller.cluster.DataPersistenceProvider;
  45 import org.opendaylight.controller.cluster.NonPersistentDataProvider;
  46 import org.opendaylight.controller.cluster.PersistentDataProvider;
  47 import org.opendaylight.controller.cluster.common.actor.AbstractUntypedPersistentActorWithMetering;
  48 import org.opendaylight.controller.cluster.datastore.exceptions.NoShardLeaderException;
  49 import org.opendaylight.controller.cluster.datastore.exceptions.NotInitializedException;
  50 import org.opendaylight.controller.cluster.datastore.exceptions.PrimaryNotFoundException;
  51 import org.opendaylight.controller.cluster.datastore.identifiers.ShardIdentifier;
  52 import org.opendaylight.controller.cluster.datastore.identifiers.ShardManagerIdentifier;
  53 import org.opendaylight.controller.cluster.datastore.jmx.mbeans.shardmanager.ShardManagerInfo;
  54 import org.opendaylight.controller.cluster.datastore.jmx.mbeans.shardmanager.ShardManagerInfoMBean;
  55 import org.opendaylight.controller.cluster.datastore.messages.ActorInitialized;
  56 import org.opendaylight.controller.cluster.datastore.messages.FindLocalShard;
  57 import org.opendaylight.controller.cluster.datastore.messages.FindPrimary;
  58 import org.opendaylight.controller.cluster.datastore.messages.LocalPrimaryShardFound;
  59 import org.opendaylight.controller.cluster.datastore.messages.LocalShardFound;
  60 import org.opendaylight.controller.cluster.datastore.messages.LocalShardNotFound;
  61 import org.opendaylight.controller.cluster.datastore.messages.PeerAddressResolved;
  62 import org.opendaylight.controller.cluster.datastore.messages.RemoteFindPrimary;
  63 import org.opendaylight.controller.cluster.datastore.messages.RemotePrimaryShardFound;
  64 import org.opendaylight.controller.cluster.datastore.messages.ShardLeaderStateChanged;
  65 import org.opendaylight.controller.cluster.datastore.messages.UpdateSchemaContext;
  66 import org.opendaylight.controller.cluster.datastore.utils.Dispatchers;
  67 import org.opendaylight.controller.cluster.notifications.RegisterRoleChangeListener;
  68 import org.opendaylight.controller.cluster.notifications.RoleChangeNotification;
  69 import org.opendaylight.controller.cluster.raft.RaftState;
  70 import org.opendaylight.controller.cluster.raft.base.messages.FollowerInitialSyncUpStatus;
  71 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTree;
  72 import org.opendaylight.yangtools.yang.model.api.ModuleIdentifier;
  73 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  74 import org.slf4j.Logger;
  75 import org.slf4j.LoggerFactory;
  76 import scala.concurrent.duration.Duration;
  77
  78 /**
  79  * The ShardManager has the following jobs,
  80  * <ul>
  81  * <li> Create all the local shard replicas that belong on this cluster member
  82  * <li> Find the address of the local shard
  83  * <li> Find the primary replica for any given shard
  84  * <li> Monitor the cluster members and store their addresses
  85  * <ul>
  86  */
  87 public class ShardManager extends AbstractUntypedPersistentActorWithMetering {
  88
  89     private static final Logger LOG = LoggerFactory.getLogger(ShardManager.class);
  90
  91     // Stores a mapping between a member name and the address of the member
  92     // Member names look like "member-1", "member-2" etc and are as specified
  93     // in configuration
  94     private final Map<String, Address> memberNameToAddress = new HashMap<>();
  95
  96     // Stores a mapping between a shard name and it's corresponding information
  97     // Shard names look like inventory, topology etc and are as specified in
  98     // configuration
  99     private final Map<String, ShardInformation> localShards = new HashMap<>();
 100
 101     // The type of a ShardManager reflects the type of the datastore itself
 102     // A data store could be of type config/operational
 103     private final String type;
 104
 105     private final String shardManagerIdentifierString;
 106
 107     private final ClusterWrapper cluster;
 108
 109     private final Configuration configuration;
 110
 111     private final String shardDispatcherPath;
 112
 113     private ShardManagerInfo mBean;
 114
 115     private DatastoreContext datastoreContext;
 116
 117     private Collection<String> knownModules = Collections.emptySet();
 118
 119     private final DataPersistenceProvider dataPersistenceProvider;
 120
 121     private final CountDownLatch waitTillReadyCountdownLatch;
 122
 123     /**
 124      */
 125     protected ShardManager(ClusterWrapper cluster, Configuration configuration,
 126             DatastoreContext datastoreContext, CountDownLatch waitTillReadyCountdownLatch) {
 127
 128         this.cluster = Preconditions.checkNotNull(cluster, "cluster should not be null");
 129         this.configuration = Preconditions.checkNotNull(configuration, "configuration should not be null");
 130         this.datastoreContext = datastoreContext;
 131         this.dataPersistenceProvider = createDataPersistenceProvider(datastoreContext.isPersistent());
 132         this.type = datastoreContext.getDataStoreType();
 133         this.shardManagerIdentifierString = ShardManagerIdentifier.builder().type(type).build().toString();
 134         this.shardDispatcherPath =
 135                 new Dispatchers(context().system().dispatchers()).getDispatcherPath(Dispatchers.DispatcherType.Shard);
 136         this.waitTillReadyCountdownLatch = waitTillReadyCountdownLatch;
 137
 138         // Subscribe this actor to cluster member events
 139         cluster.subscribeToMemberEvents(getSelf());
 140
 141         createLocalShards();
 142     }
 143
 144     protected DataPersistenceProvider createDataPersistenceProvider(boolean persistent) {
 145         return (persistent) ? new PersistentDataProvider(this) : new NonPersistentDataProvider();
 146     }
 147
 148     public static Props props(
 149         final ClusterWrapper cluster,
 150         final Configuration configuration,
 151         final DatastoreContext datastoreContext,
 152         final CountDownLatch waitTillReadyCountdownLatch) {
 153
 154         Preconditions.checkNotNull(cluster, "cluster should not be null");
 155         Preconditions.checkNotNull(configuration, "configuration should not be null");
 156         Preconditions.checkNotNull(waitTillReadyCountdownLatch, "waitTillReadyCountdownLatch should not be null");
 157
 158         return Props.create(new ShardManagerCreator(cluster, configuration, datastoreContext, waitTillReadyCountdownLatch));
 159     }
 160
 161     @Override
 162     public void postStop() {
 163         LOG.info("Stopping ShardManager");
 164
 165         mBean.unregisterMBean();
 166     }
 167
 168     @Override
 169     public void handleCommand(Object message) throws Exception {
 170         if (message  instanceof FindPrimary) {
 171             findPrimary((FindPrimary)message);
 172         } else if(message instanceof FindLocalShard){
 173             findLocalShard((FindLocalShard) message);
 174         } else if (message instanceof UpdateSchemaContext) {
 175             updateSchemaContext(message);
 176         } else if(message instanceof ActorInitialized) {
 177             onActorInitialized(message);
 178         } else if (message instanceof ClusterEvent.MemberUp){
 179             memberUp((ClusterEvent.MemberUp) message);
 180         } else if(message instanceof ClusterEvent.MemberRemoved) {
 181             memberRemoved((ClusterEvent.MemberRemoved) message);
 182         } else if(message instanceof ClusterEvent.UnreachableMember) {
 183             ignoreMessage(message);
 184         } else if(message instanceof DatastoreContext) {
 185             onDatastoreContext((DatastoreContext)message);
 186         } else if(message instanceof RoleChangeNotification) {
 187             onRoleChangeNotification((RoleChangeNotification) message);
 188         } else if(message instanceof FollowerInitialSyncUpStatus){
 189             onFollowerInitialSyncStatus((FollowerInitialSyncUpStatus) message);
 190         } else if(message instanceof ShardNotInitializedTimeout) {
 191             onShardNotInitializedTimeout((ShardNotInitializedTimeout)message);
 192         } else if(message instanceof ShardLeaderStateChanged) {
 193             onLeaderStateChanged((ShardLeaderStateChanged)message);
 194         } else {
 195             unknownMessage(message);
 196         }
 197
 198     }
 199
 200     private void checkReady(){
 201         if (isReadyWithLeaderId()) {
 202             LOG.info("{}: All Shards are ready - data store {} is ready, available count is {}",
 203                     persistenceId(), type, waitTillReadyCountdownLatch.getCount());
 204
 205             waitTillReadyCountdownLatch.countDown();
 206         }
 207     }
 208
 209     private void onLeaderStateChanged(ShardLeaderStateChanged leaderStateChanged) {
 210         LOG.info("{}: Received LeaderStateChanged message: {}", persistenceId(), leaderStateChanged);
 211
 212         ShardInformation shardInformation = findShardInformation(leaderStateChanged.getMemberId());
 213         if(shardInformation != null) {
 214             shardInformation.setLocalDataTree(leaderStateChanged.getLocalShardDataTree());
 215             shardInformation.setLeaderId(leaderStateChanged.getLeaderId());
 216             checkReady();
 217         } else {
 218             LOG.debug("No shard found with member Id {}", leaderStateChanged.getMemberId());
 219         }
 220     }
 221
 222     private void onShardNotInitializedTimeout(ShardNotInitializedTimeout message) {
 223         ShardInformation shardInfo = message.getShardInfo();
 224
 225         LOG.debug("{}: Received ShardNotInitializedTimeout message for shard {}", persistenceId(),
 226                 shardInfo.getShardName());
 227
 228         shardInfo.removeOnShardInitialized(message.getOnShardInitialized());
 229
 230         if(!shardInfo.isShardInitialized()) {
 231             LOG.debug("{}: Returning NotInitializedException for shard {}", persistenceId(), shardInfo.getShardName());
 232             message.getSender().tell(createNotInitializedException(shardInfo.shardId), getSelf());
 233         } else {
 234             LOG.debug("{}: Returning NoShardLeaderException for shard {}", persistenceId(), shardInfo.getShardName());
 235             message.getSender().tell(createNoShardLeaderException(shardInfo.shardId), getSelf());
 236         }
 237     }
 238
 239     private void onFollowerInitialSyncStatus(FollowerInitialSyncUpStatus status) {
 240         LOG.info("{} Received follower initial sync status for {} status sync done {}", persistenceId(),
 241                 status.getName(), status.isInitialSyncDone());
 242
 243         ShardInformation shardInformation = findShardInformation(status.getName());
 244
 245         if(shardInformation != null) {
 246             shardInformation.setFollowerSyncStatus(status.isInitialSyncDone());
 247
 248             mBean.setSyncStatus(isInSync());
 249         }
 250
 251     }
 252
 253     private void onRoleChangeNotification(RoleChangeNotification roleChanged) {
 254         LOG.info("{}: Received role changed for {} from {} to {}", persistenceId(), roleChanged.getMemberId(),
 255                 roleChanged.getOldRole(), roleChanged.getNewRole());
 256
 257         ShardInformation shardInformation = findShardInformation(roleChanged.getMemberId());
 258         if(shardInformation != null) {
 259             shardInformation.setRole(roleChanged.getNewRole());
 260             checkReady();
 261             mBean.setSyncStatus(isInSync());
 262         }
 263     }
 264
 265
 266     private ShardInformation findShardInformation(String memberId) {
 267         for(ShardInformation info : localShards.values()){
 268             if(info.getShardId().toString().equals(memberId)){
 269                 return info;
 270             }
 271         }
 272
 273         return null;
 274     }
 275
 276     private boolean isReadyWithLeaderId() {
 277         boolean isReady = true;
 278         for (ShardInformation info : localShards.values()) {
 279             if(!info.isShardReadyWithLeaderId()){
 280                 isReady = false;
 281                 break;
 282             }
 283         }
 284         return isReady;
 285     }
 286
 287     private boolean isInSync(){
 288         for (ShardInformation info : localShards.values()) {
 289             if(!info.isInSync()){
 290                 return false;
 291             }
 292         }
 293         return true;
 294     }
 295
 296     private void onActorInitialized(Object message) {
 297         final ActorRef sender = getSender();
 298
 299         if (sender == null) {
 300             return; //why is a non-actor sending this message? Just ignore.
 301         }
 302
 303         String actorName = sender.path().name();
 304         //find shard name from actor name; actor name is stringified shardId
 305         ShardIdentifier shardId = ShardIdentifier.builder().fromShardIdString(actorName).build();
 306
 307         if (shardId.getShardName() == null) {
 308             return;
 309         }
 310
 311         markShardAsInitialized(shardId.getShardName());
 312     }
 313
 314     private void markShardAsInitialized(String shardName) {
 315         LOG.debug("{}: Initializing shard [{}]", persistenceId(), shardName);
 316
 317         ShardInformation shardInformation = localShards.get(shardName);
 318         if (shardInformation != null) {
 319             shardInformation.setActorInitialized();
 320
 321             shardInformation.getActor().tell(new RegisterRoleChangeListener(), self());
 322         }
 323     }
 324
 325     @Override
 326     protected void handleRecover(Object message) throws Exception {
 327         if(dataPersistenceProvider.isRecoveryApplicable()) {
 328             if (message instanceof SchemaContextModules) {
 329                 SchemaContextModules msg = (SchemaContextModules) message;
 330                 knownModules = ImmutableSet.copyOf(msg.getModules());
 331             } else if (message instanceof RecoveryFailure) {
 332                 RecoveryFailure failure = (RecoveryFailure) message;
 333                 LOG.error("Recovery failed", failure.cause());
 334             } else if (message instanceof RecoveryCompleted) {
 335                 LOG.info("Recovery complete : {}", persistenceId());
 336
 337                 // Delete all the messages from the akka journal except the last one
 338                 deleteMessages(lastSequenceNr() - 1);
 339             }
 340         } else {
 341             if (message instanceof RecoveryCompleted) {
 342                 LOG.info("Recovery complete : {}", persistenceId());
 343
 344                 // Delete all the messages from the akka journal
 345                 deleteMessages(lastSequenceNr());
 346             }
 347         }
 348     }
 349
 350     private void findLocalShard(FindLocalShard message) {
 351         final ShardInformation shardInformation = localShards.get(message.getShardName());
 352
 353         if(shardInformation == null){
 354             getSender().tell(new LocalShardNotFound(message.getShardName()), getSelf());
 355             return;
 356         }
 357
 358         sendResponse(shardInformation, message.isWaitUntilInitialized(), false, new Supplier<Object>() {
 359             @Override
 360             public Object get() {
 361                 return new LocalShardFound(shardInformation.getActor());
 362             }
 363         });
 364     }
 365
 366     private void sendResponse(ShardInformation shardInformation, boolean doWait,
 367             boolean wantShardReady, final Supplier<Object> messageSupplier) {
 368         if (!shardInformation.isShardInitialized() || (wantShardReady && !shardInformation.isShardReadyWithLeaderId())) {
 369             if(doWait) {
 370                 final ActorRef sender = getSender();
 371                 final ActorRef self = self();
 372
 373                 Runnable replyRunnable = new Runnable() {
 374                     @Override
 375                     public void run() {
 376                         sender.tell(messageSupplier.get(), self);
 377                     }
 378                 };
 379
 380                 OnShardInitialized onShardInitialized = wantShardReady ? new OnShardReady(replyRunnable) :
 381                     new OnShardInitialized(replyRunnable);
 382
 383                 shardInformation.addOnShardInitialized(onShardInitialized);
 384
 385                 LOG.debug("{}: Scheduling timer to wait for shard {}", persistenceId(), shardInformation.getShardName());
 386
 387                 Cancellable timeoutSchedule = getContext().system().scheduler().scheduleOnce(
 388                         datastoreContext.getShardInitializationTimeout().duration(), getSelf(),
 389                         new ShardNotInitializedTimeout(shardInformation, onShardInitialized, sender),
 390                         getContext().dispatcher(), getSelf());
 391
 392                 onShardInitialized.setTimeoutSchedule(timeoutSchedule);
 393
 394             } else if (!shardInformation.isShardInitialized()) {
 395                 LOG.debug("{}: Returning NotInitializedException for shard {}", persistenceId(),
 396                         shardInformation.getShardName());
 397                 getSender().tell(createNotInitializedException(shardInformation.shardId), getSelf());
 398             } else {
 399                 LOG.debug("{}: Returning NoShardLeaderException for shard {}", persistenceId(),
 400                         shardInformation.getShardName());
 401                 getSender().tell(createNoShardLeaderException(shardInformation.shardId), getSelf());
 402             }
 403
 404             return;
 405         }
 406
 407         getSender().tell(messageSupplier.get(), getSelf());
 408     }
 409
 410     private NoShardLeaderException createNoShardLeaderException(ShardIdentifier shardId) {
 411         return new NoShardLeaderException(String.format(
 412                 "Could not find a leader for shard %s. This typically happens when the system is coming up or " +
 413                 "recovering and a leader is being elected. Try again later.", shardId));
 414     }
 415
 416     private NotInitializedException createNotInitializedException(ShardIdentifier shardId) {
 417         return new NotInitializedException(String.format(
 418                 "Found primary shard %s but it's not initialized yet. Please try again later", shardId));
 419     }
 420
 421     private void memberRemoved(ClusterEvent.MemberRemoved message) {
 422         String memberName = message.member().roles().head();
 423
 424         LOG.debug("{}: Received MemberRemoved: memberName: {}, address: {}", persistenceId(), memberName,
 425                 message.member().address());
 426
 427         memberNameToAddress.remove(message.member().roles().head());
 428     }
 429
 430     private void memberUp(ClusterEvent.MemberUp message) {
 431         String memberName = message.member().roles().head();
 432
 433         LOG.debug("{}: Received MemberUp: memberName: {}, address: {}", persistenceId(), memberName,
 434                 message.member().address());
 435
 436         memberNameToAddress.put(memberName, message.member().address());
 437
 438         for(ShardInformation info : localShards.values()){
 439             String shardName = info.getShardName();
 440             info.updatePeerAddress(getShardIdentifier(memberName, shardName).toString(),
 441                 getShardActorPath(shardName, memberName), getSelf());
 442         }
 443
 444         checkReady();
 445     }
 446
 447     private void onDatastoreContext(DatastoreContext context) {
 448         datastoreContext = context;
 449         for (ShardInformation info : localShards.values()) {
 450             if (info.getActor() != null) {
 451                 info.getActor().tell(datastoreContext, getSelf());
 452             }
 453         }
 454     }
 455
 456     /**
 457      * Notifies all the local shards of a change in the schema context
 458      *
 459      * @param message
 460      */
 461     private void updateSchemaContext(final Object message) {
 462         final SchemaContext schemaContext = ((UpdateSchemaContext) message).getSchemaContext();
 463
 464         Set<ModuleIdentifier> allModuleIdentifiers = schemaContext.getAllModuleIdentifiers();
 465         Set<String> newModules = new HashSet<>(128);
 466
 467         for(ModuleIdentifier moduleIdentifier : allModuleIdentifiers){
 468             String s = moduleIdentifier.getNamespace().toString();
 469             newModules.add(s);
 470         }
 471
 472         if(newModules.containsAll(knownModules)) {
 473
 474             LOG.debug("New SchemaContext has a super set of current knownModules - persisting info");
 475
 476             knownModules = ImmutableSet.copyOf(newModules);
 477
 478             dataPersistenceProvider.persist(new SchemaContextModules(newModules), new Procedure<SchemaContextModules>() {
 479
 480                 @Override
 481                 public void apply(SchemaContextModules param) throws Exception {
 482                     LOG.debug("Sending new SchemaContext to Shards");
 483                     for (ShardInformation info : localShards.values()) {
 484                         if (info.getActor() == null) {
 485                             info.setActor(newShardActor(schemaContext, info));
 486                         } else {
 487                             info.getActor().tell(message, getSelf());
 488                         }
 489                     }
 490                 }
 491
 492             });
 493         } else {
 494             LOG.debug("Rejecting schema context update - not a super set of previously known modules:\nUPDATE: {}\nKNOWN: {}",
 495                     newModules, knownModules);
 496         }
 497
 498     }
 499
 500     @VisibleForTesting
 501     protected ClusterWrapper getCluster() {
 502         return cluster;
 503     }
 504
 505     @VisibleForTesting
 506     protected ActorRef newShardActor(final SchemaContext schemaContext, ShardInformation info) {
 507         return getContext().actorOf(Shard.props(info.getShardId(),
 508                 info.getPeerAddresses(), datastoreContext, schemaContext)
 509                         .withDispatcher(shardDispatcherPath), info.getShardId().toString());
 510     }
 511
 512     private void findPrimary(FindPrimary message) {
 513         LOG.debug("{}: In findPrimary: {}", persistenceId(), message);
 514
 515         final String shardName = message.getShardName();
 516         final boolean canReturnLocalShardState = !(message instanceof RemoteFindPrimary);
 517
 518         // First see if the there is a local replica for the shard
 519         final ShardInformation info = localShards.get(shardName);
 520         if (info != null) {
 521             sendResponse(info, message.isWaitUntilReady(), true, new Supplier<Object>() {
 522                 @Override
 523                 public Object get() {
 524                     String primaryPath = info.getSerializedLeaderActor();
 525                     Object found = canReturnLocalShardState && info.isLeader() ?
 526                             new LocalPrimaryShardFound(primaryPath, info.getLocalShardDataTree().get()) :
 527                                 new RemotePrimaryShardFound(primaryPath);
 528
 529                     if(LOG.isDebugEnabled()) {
 530                         LOG.debug("{}: Found primary for {}: {}", persistenceId(), shardName, found);
 531                     }
 532
 533                     return found;
 534                 }
 535             });
 536
 537             return;
 538         }
 539
 540         for(Map.Entry<String, Address> entry: memberNameToAddress.entrySet()) {
 541             if(!cluster.getCurrentMemberName().equals(entry.getKey())) {
 542                 String path = getShardManagerActorPathBuilder(entry.getValue()).toString();
 543
 544                 LOG.debug("{}: findPrimary for {} forwarding to remote ShardManager {}", persistenceId(),
 545                         shardName, path);
 546
 547                 getContext().actorSelection(path).forward(new RemoteFindPrimary(shardName,
 548                         message.isWaitUntilReady()), getContext());
 549                 return;
 550             }
 551         }
 552
 553         LOG.debug("{}: No shard found for {}", persistenceId(), shardName);
 554
 555         getSender().tell(new PrimaryNotFoundException(
 556                 String.format("No primary shard found for %s.", shardName)), getSelf());
 557     }
 558
 559     private StringBuilder getShardManagerActorPathBuilder(Address address) {
 560         StringBuilder builder = new StringBuilder();
 561         builder.append(address.toString()).append("/user/").append(shardManagerIdentifierString);
 562         return builder;
 563     }
 564
 565     private String getShardActorPath(String shardName, String memberName) {
 566         Address address = memberNameToAddress.get(memberName);
 567         if(address != null) {
 568             StringBuilder builder = getShardManagerActorPathBuilder(address);
 569             builder.append("/")
 570                 .append(getShardIdentifier(memberName, shardName));
 571             return builder.toString();
 572         }
 573         return null;
 574     }
 575
 576     /**
 577      * Construct the name of the shard actor given the name of the member on
 578      * which the shard resides and the name of the shard
 579      *
 580      * @param memberName
 581      * @param shardName
 582      * @return
 583      */
 584     private ShardIdentifier getShardIdentifier(String memberName, String shardName){
 585         return ShardIdentifier.builder().memberName(memberName).shardName(shardName).type(type).build();
 586     }
 587
 588     /**
 589      * Create shards that are local to the member on which the ShardManager
 590      * runs
 591      *
 592      */
 593     private void createLocalShards() {
 594         String memberName = this.cluster.getCurrentMemberName();
 595         List<String> memberShardNames =
 596             this.configuration.getMemberShardNames(memberName);
 597
 598         List<String> localShardActorNames = new ArrayList<>();
 599         for(String shardName : memberShardNames){
 600             ShardIdentifier shardId = getShardIdentifier(memberName, shardName);
 601             Map<String, String> peerAddresses = getPeerAddresses(shardName);
 602             localShardActorNames.add(shardId.toString());
 603             localShards.put(shardName, new ShardInformation(shardName, shardId, peerAddresses));
 604         }
 605
 606         mBean = ShardManagerInfo.createShardManagerMBean("shard-manager-" + this.type,
 607                     datastoreContext.getDataStoreMXBeanType(), localShardActorNames);
 608     }
 609
 610     /**
 611      * Given the name of the shard find the addresses of all it's peers
 612      *
 613      * @param shardName
 614      * @return
 615      */
 616     private Map<String, String> getPeerAddresses(String shardName){
 617
 618         Map<String, String> peerAddresses = new HashMap<>();
 619
 620         List<String> members = this.configuration.getMembersFromShardName(shardName);
 621
 622         String currentMemberName = this.cluster.getCurrentMemberName();
 623
 624         for(String memberName : members){
 625             if(!currentMemberName.equals(memberName)){
 626                 ShardIdentifier shardId = getShardIdentifier(memberName, shardName);
 627                 String path = getShardActorPath(shardName, currentMemberName);
 628                 peerAddresses.put(shardId.toString(), path);
 629             }
 630         }
 631         return peerAddresses;
 632     }
 633
 634     @Override
 635     public SupervisorStrategy supervisorStrategy() {
 636
 637         return new OneForOneStrategy(10, Duration.create("1 minute"),
 638             new Function<Throwable, SupervisorStrategy.Directive>() {
 639                 @Override
 640                 public SupervisorStrategy.Directive apply(Throwable t) {
 641                     LOG.warn("Supervisor Strategy caught unexpected exception - resuming", t);
 642                     return SupervisorStrategy.resume();
 643                 }
 644             }
 645         );
 646
 647     }
 648
 649     @Override
 650     public String persistenceId() {
 651         return "shard-manager-" + type;
 652     }
 653
 654     @VisibleForTesting
 655     Collection<String> getKnownModules() {
 656         return knownModules;
 657     }
 658
 659     @VisibleForTesting
 660     DataPersistenceProvider getDataPersistenceProvider() {
 661         return dataPersistenceProvider;
 662     }
 663
 664     @VisibleForTesting
 665     ShardManagerInfoMBean getMBean(){
 666         return mBean;
 667     }
 668
 669     @VisibleForTesting
 670     protected static class ShardInformation {
 671         private final ShardIdentifier shardId;
 672         private final String shardName;
 673         private ActorRef actor;
 674         private ActorPath actorPath;
 675         private final Map<String, String> peerAddresses;
 676         private Optional<DataTree> localShardDataTree;
 677
 678         // flag that determines if the actor is ready for business
 679         private boolean actorInitialized = false;
 680
 681         private boolean followerSyncStatus = false;
 682
 683         private final Set<OnShardInitialized> onShardInitializedSet = Sets.newHashSet();
 684         private String role ;
 685         private String leaderId;
 686
 687         private ShardInformation(String shardName, ShardIdentifier shardId,
 688                 Map<String, String> peerAddresses) {
 689             this.shardName = shardName;
 690             this.shardId = shardId;
 691             this.peerAddresses = peerAddresses;
 692         }
 693
 694         String getShardName() {
 695             return shardName;
 696         }
 697
 698         ActorRef getActor(){
 699             return actor;
 700         }
 701
 702         ActorPath getActorPath() {
 703             return actorPath;
 704         }
 705
 706         void setActor(ActorRef actor) {
 707             this.actor = actor;
 708             this.actorPath = actor.path();
 709         }
 710
 711         ShardIdentifier getShardId() {
 712             return shardId;
 713         }
 714
 715         void setLocalDataTree(Optional<DataTree> localShardDataTree) {
 716             this.localShardDataTree = localShardDataTree;
 717         }
 718
 719         Optional<DataTree> getLocalShardDataTree() {
 720             return localShardDataTree;
 721         }
 722
 723         Map<String, String> getPeerAddresses() {
 724             return peerAddresses;
 725         }
 726
 727         void updatePeerAddress(String peerId, String peerAddress, ActorRef sender){
 728             LOG.info("updatePeerAddress for peer {} with address {}", peerId,
 729                 peerAddress);
 730             if(peerAddresses.containsKey(peerId)){
 731                 peerAddresses.put(peerId, peerAddress);
 732
 733                 if(actor != null) {
 734                     if(LOG.isDebugEnabled()) {
 735                         LOG.debug("Sending PeerAddressResolved for peer {} with address {} to {}",
 736                                 peerId, peerAddress, actor.path());
 737                     }
 738
 739                     actor.tell(new PeerAddressResolved(peerId.toString(), peerAddress), sender);
 740                 }
 741
 742                 notifyOnShardInitializedCallbacks();
 743             }
 744         }
 745
 746         boolean isShardReady() {
 747             return !RaftState.Candidate.name().equals(role) && !Strings.isNullOrEmpty(role);
 748         }
 749
 750         boolean isShardReadyWithLeaderId() {
 751             return isShardReady() && (isLeader() || peerAddresses.get(leaderId) != null);
 752         }
 753
 754         boolean isShardInitialized() {
 755             return getActor() != null && actorInitialized;
 756         }
 757
 758         boolean isLeader() {
 759             return Objects.equal(leaderId, shardId.toString());
 760         }
 761
 762         String getSerializedLeaderActor() {
 763             if(isLeader()) {
 764                 return Serialization.serializedActorPath(getActor());
 765             } else {
 766                 return peerAddresses.get(leaderId);
 767             }
 768         }
 769
 770         void setActorInitialized() {
 771             LOG.debug("Shard {} is initialized", shardId);
 772
 773             this.actorInitialized = true;
 774
 775             notifyOnShardInitializedCallbacks();
 776         }
 777
 778         private void notifyOnShardInitializedCallbacks() {
 779             if(onShardInitializedSet.isEmpty()) {
 780                 return;
 781             }
 782
 783             boolean ready = isShardReadyWithLeaderId();
 784
 785             if(LOG.isDebugEnabled()) {
 786                 LOG.debug("Shard {} is {} - notifying {} OnShardInitialized callbacks", shardId,
 787                         ready ? "ready" : "initialized", onShardInitializedSet.size());
 788             }
 789
 790             Iterator<OnShardInitialized> iter = onShardInitializedSet.iterator();
 791             while(iter.hasNext()) {
 792                 OnShardInitialized onShardInitialized = iter.next();
 793                 if(!(onShardInitialized instanceof OnShardReady) || ready) {
 794                     iter.remove();
 795                     onShardInitialized.getTimeoutSchedule().cancel();
 796                     onShardInitialized.getReplyRunnable().run();
 797                 }
 798             }
 799         }
 800
 801         void addOnShardInitialized(OnShardInitialized onShardInitialized) {
 802             onShardInitializedSet.add(onShardInitialized);
 803         }
 804
 805         void removeOnShardInitialized(OnShardInitialized onShardInitialized) {
 806             onShardInitializedSet.remove(onShardInitialized);
 807         }
 808
 809         void setRole(String newRole) {
 810             this.role = newRole;
 811
 812             notifyOnShardInitializedCallbacks();
 813         }
 814
 815         void setFollowerSyncStatus(boolean syncStatus){
 816             this.followerSyncStatus = syncStatus;
 817         }
 818
 819         boolean isInSync(){
 820             if(RaftState.Follower.name().equals(this.role)){
 821                 return followerSyncStatus;
 822             } else if(RaftState.Leader.name().equals(this.role)){
 823                 return true;
 824             }
 825
 826             return false;
 827         }
 828
 829         void setLeaderId(String leaderId) {
 830             this.leaderId = leaderId;
 831
 832             notifyOnShardInitializedCallbacks();
 833         }
 834     }
 835
 836     private static class ShardManagerCreator implements Creator<ShardManager> {
 837         private static final long serialVersionUID = 1L;
 838
 839         final ClusterWrapper cluster;
 840         final Configuration configuration;
 841         final DatastoreContext datastoreContext;
 842         private final CountDownLatch waitTillReadyCountdownLatch;
 843
 844         ShardManagerCreator(ClusterWrapper cluster,
 845                             Configuration configuration, DatastoreContext datastoreContext, CountDownLatch waitTillReadyCountdownLatch) {
 846             this.cluster = cluster;
 847             this.configuration = configuration;
 848             this.datastoreContext = datastoreContext;
 849             this.waitTillReadyCountdownLatch = waitTillReadyCountdownLatch;
 850         }
 851
 852         @Override
 853         public ShardManager create() throws Exception {
 854             return new ShardManager(cluster, configuration, datastoreContext, waitTillReadyCountdownLatch);
 855         }
 856     }
 857
 858     private static class OnShardInitialized {
 859         private final Runnable replyRunnable;
 860         private Cancellable timeoutSchedule;
 861
 862         OnShardInitialized(Runnable replyRunnable) {
 863             this.replyRunnable = replyRunnable;
 864         }
 865
 866         Runnable getReplyRunnable() {
 867             return replyRunnable;
 868         }
 869
 870         Cancellable getTimeoutSchedule() {
 871             return timeoutSchedule;
 872         }
 873
 874         void setTimeoutSchedule(Cancellable timeoutSchedule) {
 875             this.timeoutSchedule = timeoutSchedule;
 876         }
 877     }
 878
 879     private static class OnShardReady extends OnShardInitialized {
 880         OnShardReady(Runnable replyRunnable) {
 881             super(replyRunnable);
 882         }
 883     }
 884
 885     private static class ShardNotInitializedTimeout {
 886         private final ActorRef sender;
 887         private final ShardInformation shardInfo;
 888         private final OnShardInitialized onShardInitialized;
 889
 890         ShardNotInitializedTimeout(ShardInformation shardInfo, OnShardInitialized onShardInitialized, ActorRef sender) {
 891             this.sender = sender;
 892             this.shardInfo = shardInfo;
 893             this.onShardInitialized = onShardInitialized;
 894         }
 895
 896         ActorRef getSender() {
 897             return sender;
 898         }
 899
 900         ShardInformation getShardInfo() {
 901             return shardInfo;
 902         }
 903
 904         OnShardInitialized getOnShardInitialized() {
 905             return onShardInitialized;
 906         }
 907     }
 908
 909     static class SchemaContextModules implements Serializable {
 910         private static final long serialVersionUID = -8884620101025936590L;
 911
 912         private final Set<String> modules;
 913
 914         SchemaContextModules(Set<String> modules){
 915             this.modules = modules;
 916         }
 917
 918         public Set<String> getModules() {
 919             return modules;
 920         }
 921     }
 922 }
 923
 924
 925