opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/Shard.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.ActorRef;
  12 import akka.actor.ActorSelection;
  13 import akka.actor.Cancellable;
  14 import akka.actor.Props;
  15 import akka.japi.Creator;
  16 import akka.persistence.RecoveryFailure;
  17 import akka.serialization.Serialization;
  18 import com.google.common.annotations.VisibleForTesting;
  19 import com.google.common.base.Optional;
  20 import com.google.common.base.Preconditions;
  21 import com.google.common.collect.Lists;
  22 import com.google.common.util.concurrent.FutureCallback;
  23 import com.google.common.util.concurrent.Futures;
  24 import com.google.common.util.concurrent.ListenableFuture;
  25 import java.io.IOException;
  26 import java.util.Collection;
  27 import java.util.HashMap;
  28 import java.util.List;
  29 import java.util.Map;
  30 import java.util.concurrent.ExecutionException;
  31 import java.util.concurrent.TimeUnit;
  32 import javax.annotation.Nonnull;
  33 import org.opendaylight.controller.cluster.DataPersistenceProvider;
  34 import org.opendaylight.controller.cluster.common.actor.CommonConfig;
  35 import org.opendaylight.controller.cluster.common.actor.MeteringBehavior;
  36 import org.opendaylight.controller.cluster.datastore.ShardCommitCoordinator.CohortEntry;
  37 import org.opendaylight.controller.cluster.datastore.compat.BackwardsCompatibleThreePhaseCommitCohort;
  38 import org.opendaylight.controller.cluster.datastore.exceptions.NoShardLeaderException;
  39 import org.opendaylight.controller.cluster.datastore.identifiers.ShardIdentifier;
  40 import org.opendaylight.controller.cluster.datastore.identifiers.ShardTransactionIdentifier;
  41 import org.opendaylight.controller.cluster.datastore.jmx.mbeans.shard.ShardMBeanFactory;
  42 import org.opendaylight.controller.cluster.datastore.jmx.mbeans.shard.ShardStats;
  43 import org.opendaylight.controller.cluster.datastore.messages.AbortTransaction;
  44 import org.opendaylight.controller.cluster.datastore.messages.AbortTransactionReply;
  45 import org.opendaylight.controller.cluster.datastore.messages.ActorInitialized;
  46 import org.opendaylight.controller.cluster.datastore.messages.CanCommitTransaction;
  47 import org.opendaylight.controller.cluster.datastore.messages.CloseTransactionChain;
  48 import org.opendaylight.controller.cluster.datastore.messages.CommitTransaction;
  49 import org.opendaylight.controller.cluster.datastore.messages.CommitTransactionReply;
  50 import org.opendaylight.controller.cluster.datastore.messages.CreateSnapshot;
  51 import org.opendaylight.controller.cluster.datastore.messages.CreateTransaction;
  52 import org.opendaylight.controller.cluster.datastore.messages.CreateTransactionReply;
  53 import org.opendaylight.controller.cluster.datastore.messages.EnableNotification;
  54 import org.opendaylight.controller.cluster.datastore.messages.ForwardedReadyTransaction;
  55 import org.opendaylight.controller.cluster.datastore.messages.PeerAddressResolved;
  56 import org.opendaylight.controller.cluster.datastore.messages.ReadyTransactionReply;
  57 import org.opendaylight.controller.cluster.datastore.messages.RegisterChangeListener;
  58 import org.opendaylight.controller.cluster.datastore.messages.RegisterChangeListenerReply;
  59 import org.opendaylight.controller.cluster.datastore.messages.UpdateSchemaContext;
  60 import org.opendaylight.controller.cluster.datastore.modification.Modification;
  61 import org.opendaylight.controller.cluster.datastore.modification.ModificationPayload;
  62 import org.opendaylight.controller.cluster.datastore.modification.MutableCompositeModification;
  63 import org.opendaylight.controller.cluster.datastore.utils.MessageTracker;
  64 import org.opendaylight.controller.cluster.datastore.utils.SerializationUtils;
  65 import org.opendaylight.controller.cluster.notifications.RoleChangeNotifier;
  66 import org.opendaylight.controller.cluster.raft.RaftActor;
  67 import org.opendaylight.controller.cluster.raft.ReplicatedLogEntry;
  68 import org.opendaylight.controller.cluster.raft.messages.AppendEntriesReply;
  69 import org.opendaylight.controller.cluster.raft.protobuff.client.messages.CompositeModificationByteStringPayload;
  70 import org.opendaylight.controller.cluster.raft.protobuff.client.messages.CompositeModificationPayload;
  71 import org.opendaylight.controller.cluster.raft.protobuff.client.messages.Payload;
  72 import org.opendaylight.controller.md.sal.common.api.data.AsyncDataChangeListener;
  73 import org.opendaylight.controller.md.sal.dom.store.impl.InMemoryDOMDataStore;
  74 import org.opendaylight.controller.md.sal.dom.store.impl.InMemoryDOMDataStoreFactory;
  75 import org.opendaylight.controller.sal.core.spi.data.DOMStoreThreePhaseCommitCohort;
  76 import org.opendaylight.controller.sal.core.spi.data.DOMStoreTransactionChain;
  77 import org.opendaylight.controller.sal.core.spi.data.DOMStoreTransactionFactory;
  78 import org.opendaylight.controller.sal.core.spi.data.DOMStoreWriteTransaction;
  79 import org.opendaylight.yangtools.concepts.ListenerRegistration;
  80 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  81 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  82 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  83 import scala.concurrent.duration.Duration;
  84 import scala.concurrent.duration.FiniteDuration;
  85
  86 /**
  87  * A Shard represents a portion of the logical data tree <br/>
  88  * <p>
  89  * Our Shard uses InMemoryDataStore as it's internal representation and delegates all requests it
  90  * </p>
  91  */
  92 public class Shard extends RaftActor {
  93
  94     private static final YangInstanceIdentifier DATASTORE_ROOT = YangInstanceIdentifier.builder().build();
  95
  96     private static final Object TX_COMMIT_TIMEOUT_CHECK_MESSAGE = "txCommitTimeoutCheck";
  97
  98     @VisibleForTesting
  99     static final String DEFAULT_NAME = "default";
 100
 101     // The state of this Shard
 102     private final InMemoryDOMDataStore store;
 103
 104     /// The name of this shard
 105     private final ShardIdentifier name;
 106
 107     private final ShardStats shardMBean;
 108
 109     private final List<ActorSelection> dataChangeListeners =  Lists.newArrayList();
 110
 111     private final List<DelayedListenerRegistration> delayedListenerRegistrations =
 112                                                                        Lists.newArrayList();
 113
 114     private final DatastoreContext datastoreContext;
 115
 116     private final DataPersistenceProvider dataPersistenceProvider;
 117
 118     private SchemaContext schemaContext;
 119
 120     private int createSnapshotTransactionCounter;
 121
 122     private final ShardCommitCoordinator commitCoordinator;
 123
 124     private final long transactionCommitTimeout;
 125
 126     private Cancellable txCommitTimeoutCheckSchedule;
 127
 128     private final Optional<ActorRef> roleChangeNotifier;
 129
 130     private final MessageTracker appendEntriesReplyTracker;
 131
 132     /**
 133      * Coordinates persistence recovery on startup.
 134      */
 135     private ShardRecoveryCoordinator recoveryCoordinator;
 136     private List<Object> currentLogRecoveryBatch;
 137
 138     private final Map<String, DOMStoreTransactionChain> transactionChains = new HashMap<>();
 139
 140     protected Shard(final ShardIdentifier name, final Map<ShardIdentifier, String> peerAddresses,
 141             final DatastoreContext datastoreContext, final SchemaContext schemaContext) {
 142         super(name.toString(), mapPeerAddresses(peerAddresses),
 143                 Optional.of(datastoreContext.getShardRaftConfig()));
 144
 145         this.name = name;
 146         this.datastoreContext = datastoreContext;
 147         this.schemaContext = schemaContext;
 148         this.dataPersistenceProvider = (datastoreContext.isPersistent()) ? new PersistentDataProvider() : new NonPersistentRaftDataProvider();
 149
 150         LOG.info("Shard created : {}, persistent : {}", name, datastoreContext.isPersistent());
 151
 152         store = InMemoryDOMDataStoreFactory.create(name.toString(), null,
 153                 datastoreContext.getDataStoreProperties());
 154
 155         if(schemaContext != null) {
 156             store.onGlobalContextUpdated(schemaContext);
 157         }
 158
 159         shardMBean = ShardMBeanFactory.getShardStatsMBean(name.toString(),
 160                 datastoreContext.getDataStoreMXBeanType());
 161         shardMBean.setNotificationManager(store.getDataChangeListenerNotificationManager());
 162
 163         if (isMetricsCaptureEnabled()) {
 164             getContext().become(new MeteringBehavior(this));
 165         }
 166
 167         commitCoordinator = new ShardCommitCoordinator(TimeUnit.SECONDS.convert(1, TimeUnit.MINUTES),
 168                 datastoreContext.getShardTransactionCommitQueueCapacity(), LOG, name.toString());
 169
 170         transactionCommitTimeout = TimeUnit.MILLISECONDS.convert(
 171                 datastoreContext.getShardTransactionCommitTimeoutInSeconds(), TimeUnit.SECONDS);
 172
 173         // create a notifier actor for each cluster member
 174         roleChangeNotifier = createRoleChangeNotifier(name.toString());
 175
 176         appendEntriesReplyTracker = new MessageTracker(AppendEntriesReply.class,
 177                 getRaftActorContext().getConfigParams().getIsolatedCheckIntervalInMillis());
 178     }
 179
 180     private static Map<String, String> mapPeerAddresses(
 181         final Map<ShardIdentifier, String> peerAddresses) {
 182         Map<String, String> map = new HashMap<>();
 183
 184         for (Map.Entry<ShardIdentifier, String> entry : peerAddresses
 185             .entrySet()) {
 186             map.put(entry.getKey().toString(), entry.getValue());
 187         }
 188
 189         return map;
 190     }
 191
 192     public static Props props(final ShardIdentifier name,
 193         final Map<ShardIdentifier, String> peerAddresses,
 194         final DatastoreContext datastoreContext, final SchemaContext schemaContext) {
 195         Preconditions.checkNotNull(name, "name should not be null");
 196         Preconditions.checkNotNull(peerAddresses, "peerAddresses should not be null");
 197         Preconditions.checkNotNull(datastoreContext, "dataStoreContext should not be null");
 198         Preconditions.checkNotNull(schemaContext, "schemaContext should not be null");
 199
 200         return Props.create(new ShardCreator(name, peerAddresses, datastoreContext, schemaContext));
 201     }
 202
 203     private Optional<ActorRef> createRoleChangeNotifier(String shardId) {
 204         ActorRef shardRoleChangeNotifier = this.getContext().actorOf(
 205             RoleChangeNotifier.getProps(shardId), shardId + "-notifier");
 206         return Optional.<ActorRef>of(shardRoleChangeNotifier);
 207     }
 208
 209     @Override
 210     public void postStop() {
 211         super.postStop();
 212
 213         if(txCommitTimeoutCheckSchedule != null) {
 214             txCommitTimeoutCheckSchedule.cancel();
 215         }
 216     }
 217
 218     @Override
 219     public void onReceiveRecover(final Object message) throws Exception {
 220         if(LOG.isDebugEnabled()) {
 221             LOG.debug("{}: onReceiveRecover: Received message {} from {}", persistenceId(),
 222                 message.getClass().toString(), getSender());
 223         }
 224
 225         if (message instanceof RecoveryFailure){
 226             LOG.error("{}: Recovery failed because of this cause",
 227                     persistenceId(), ((RecoveryFailure) message).cause());
 228
 229             // Even though recovery failed, we still need to finish our recovery, eg send the
 230             // ActorInitialized message and start the txCommitTimeoutCheckSchedule.
 231             onRecoveryComplete();
 232         } else {
 233             super.onReceiveRecover(message);
 234             if(LOG.isTraceEnabled()) {
 235                 appendEntriesReplyTracker.begin();
 236             }
 237         }
 238     }
 239
 240     @Override
 241     public void onReceiveCommand(final Object message) throws Exception {
 242
 243         MessageTracker.Context context = appendEntriesReplyTracker.received(message);
 244
 245         if(context.error().isPresent()){
 246             LOG.trace("{} : AppendEntriesReply failed to arrive at the expected interval {}", persistenceId(),
 247                     context.error());
 248         }
 249
 250         try {
 251             if (message.getClass().equals(CreateTransaction.SERIALIZABLE_CLASS)) {
 252                 handleCreateTransaction(message);
 253             } else if (message instanceof ForwardedReadyTransaction) {
 254                 handleForwardedReadyTransaction((ForwardedReadyTransaction) message);
 255             } else if (message.getClass().equals(CanCommitTransaction.SERIALIZABLE_CLASS)) {
 256                 handleCanCommitTransaction(CanCommitTransaction.fromSerializable(message));
 257             } else if (message.getClass().equals(CommitTransaction.SERIALIZABLE_CLASS)) {
 258                 handleCommitTransaction(CommitTransaction.fromSerializable(message));
 259             } else if (message.getClass().equals(AbortTransaction.SERIALIZABLE_CLASS)) {
 260                 handleAbortTransaction(AbortTransaction.fromSerializable(message));
 261             } else if (message.getClass().equals(CloseTransactionChain.SERIALIZABLE_CLASS)) {
 262                 closeTransactionChain(CloseTransactionChain.fromSerializable(message));
 263             } else if (message instanceof RegisterChangeListener) {
 264                 registerChangeListener((RegisterChangeListener) message);
 265             } else if (message instanceof UpdateSchemaContext) {
 266                 updateSchemaContext((UpdateSchemaContext) message);
 267             } else if (message instanceof PeerAddressResolved) {
 268                 PeerAddressResolved resolved = (PeerAddressResolved) message;
 269                 setPeerAddress(resolved.getPeerId().toString(),
 270                         resolved.getPeerAddress());
 271             } else if (message.equals(TX_COMMIT_TIMEOUT_CHECK_MESSAGE)) {
 272                 handleTransactionCommitTimeoutCheck();
 273             } else {
 274                 super.onReceiveCommand(message);
 275             }
 276         } finally {
 277             context.done();
 278         }
 279     }
 280
 281     @Override
 282     protected Optional<ActorRef> getRoleChangeNotifier() {
 283         return roleChangeNotifier;
 284     }
 285
 286     private void handleTransactionCommitTimeoutCheck() {
 287         CohortEntry cohortEntry = commitCoordinator.getCurrentCohortEntry();
 288         if(cohortEntry != null) {
 289             long elapsed = System.currentTimeMillis() - cohortEntry.getLastAccessTime();
 290             if(elapsed > transactionCommitTimeout) {
 291                 LOG.warn("{}: Current transaction {} has timed out after {} ms - aborting",
 292                         persistenceId(), cohortEntry.getTransactionID(), transactionCommitTimeout);
 293
 294                 doAbortTransaction(cohortEntry.getTransactionID(), null);
 295             }
 296         }
 297     }
 298
 299     private void handleCommitTransaction(final CommitTransaction commit) {
 300         final String transactionID = commit.getTransactionID();
 301
 302         LOG.debug("{}: Committing transaction {}", persistenceId(), transactionID);
 303
 304         // Get the current in-progress cohort entry in the commitCoordinator if it corresponds to
 305         // this transaction.
 306         final CohortEntry cohortEntry = commitCoordinator.getCohortEntryIfCurrent(transactionID);
 307         if(cohortEntry == null) {
 308             // We're not the current Tx - the Tx was likely expired b/c it took too long in
 309             // between the canCommit and commit messages.
 310             IllegalStateException ex = new IllegalStateException(
 311                     String.format("%s: Cannot commit transaction %s - it is not the current transaction",
 312                             persistenceId(), transactionID));
 313             LOG.error(ex.getMessage());
 314             shardMBean.incrementFailedTransactionsCount();
 315             getSender().tell(new akka.actor.Status.Failure(ex), getSelf());
 316             return;
 317         }
 318
 319         // We perform the preCommit phase here atomically with the commit phase. This is an
 320         // optimization to eliminate the overhead of an extra preCommit message. We lose front-end
 321         // coordination of preCommit across shards in case of failure but preCommit should not
 322         // normally fail since we ensure only one concurrent 3-phase commit.
 323
 324         try {
 325             // We block on the future here so we don't have to worry about possibly accessing our
 326             // state on a different thread outside of our dispatcher. Also, the data store
 327             // currently uses a same thread executor anyway.
 328             cohortEntry.getCohort().preCommit().get();
 329
 330             // If we do not have any followers and we are not using persistence we can
 331             // apply modification to the state immediately
 332             if(!hasFollowers() && !persistence().isRecoveryApplicable()){
 333                 applyModificationToState(getSender(), transactionID, cohortEntry.getModification());
 334             } else {
 335                 Shard.this.persistData(getSender(), transactionID,
 336                         new ModificationPayload(cohortEntry.getModification()));
 337             }
 338         } catch (Exception e) {
 339             LOG.error("{} An exception occurred while preCommitting transaction {}",
 340                     persistenceId(), cohortEntry.getTransactionID(), e);
 341             shardMBean.incrementFailedTransactionsCount();
 342             getSender().tell(new akka.actor.Status.Failure(e), getSelf());
 343         }
 344
 345         cohortEntry.updateLastAccessTime();
 346     }
 347
 348     private void finishCommit(@Nonnull final ActorRef sender, final @Nonnull String transactionID) {
 349         // With persistence enabled, this method is called via applyState by the leader strategy
 350         // after the commit has been replicated to a majority of the followers.
 351
 352         CohortEntry cohortEntry = commitCoordinator.getCohortEntryIfCurrent(transactionID);
 353         if(cohortEntry == null) {
 354             // The transaction is no longer the current commit. This can happen if the transaction
 355             // was aborted prior, most likely due to timeout in the front-end. We need to finish
 356             // committing the transaction though since it was successfully persisted and replicated
 357             // however we can't use the original cohort b/c it was already preCommitted and may
 358             // conflict with the current commit or may have been aborted so we commit with a new
 359             // transaction.
 360             cohortEntry = commitCoordinator.getAndRemoveCohortEntry(transactionID);
 361             if(cohortEntry != null) {
 362                 commitWithNewTransaction(cohortEntry.getModification());
 363                 sender.tell(CommitTransactionReply.INSTANCE.toSerializable(), getSelf());
 364             } else {
 365                 // This really shouldn't happen - it likely means that persistence or replication
 366                 // took so long to complete such that the cohort entry was expired from the cache.
 367                 IllegalStateException ex = new IllegalStateException(
 368                         String.format("%s: Could not finish committing transaction %s - no CohortEntry found",
 369                                 persistenceId(), transactionID));
 370                 LOG.error(ex.getMessage());
 371                 sender.tell(new akka.actor.Status.Failure(ex), getSelf());
 372             }
 373
 374             return;
 375         }
 376
 377         LOG.debug("{}: Finishing commit for transaction {}", persistenceId(), cohortEntry.getTransactionID());
 378
 379         try {
 380             // We block on the future here so we don't have to worry about possibly accessing our
 381             // state on a different thread outside of our dispatcher. Also, the data store
 382             // currently uses a same thread executor anyway.
 383             cohortEntry.getCohort().commit().get();
 384
 385             sender.tell(CommitTransactionReply.INSTANCE.toSerializable(), getSelf());
 386
 387             shardMBean.incrementCommittedTransactionCount();
 388             shardMBean.setLastCommittedTransactionTime(System.currentTimeMillis());
 389
 390         } catch (Exception e) {
 391             sender.tell(new akka.actor.Status.Failure(e), getSelf());
 392
 393             LOG.error("{}, An exception occurred while committing transaction {}", persistenceId(),
 394                     transactionID, e);
 395             shardMBean.incrementFailedTransactionsCount();
 396         } finally {
 397             commitCoordinator.currentTransactionComplete(transactionID, true);
 398         }
 399     }
 400
 401     private void handleCanCommitTransaction(final CanCommitTransaction canCommit) {
 402         LOG.debug("{}: Can committing transaction {}", persistenceId(), canCommit.getTransactionID());
 403         commitCoordinator.handleCanCommit(canCommit, getSender(), self());
 404     }
 405
 406     private void handleForwardedReadyTransaction(ForwardedReadyTransaction ready) {
 407         LOG.debug("{}: Readying transaction {}, client version {}", persistenceId(),
 408                 ready.getTransactionID(), ready.getTxnClientVersion());
 409
 410         // This message is forwarded by the ShardTransaction on ready. We cache the cohort in the
 411         // commitCoordinator in preparation for the subsequent three phase commit initiated by
 412         // the front-end.
 413         commitCoordinator.transactionReady(ready.getTransactionID(), ready.getCohort(),
 414                 ready.getModification());
 415
 416         // Return our actor path as we'll handle the three phase commit, except if the Tx client
 417         // version < 1 (Helium-1 version). This means the Tx was initiated by a base Helium version
 418         // node. In that case, the subsequent 3-phase commit messages won't contain the
 419         // transactionId so to maintain backwards compatibility, we create a separate cohort actor
 420         // to provide the compatible behavior.
 421         ActorRef replyActorPath = self();
 422         if(ready.getTxnClientVersion() < DataStoreVersions.HELIUM_1_VERSION) {
 423             LOG.debug("{}: Creating BackwardsCompatibleThreePhaseCommitCohort", persistenceId());
 424             replyActorPath = getContext().actorOf(BackwardsCompatibleThreePhaseCommitCohort.props(
 425                     ready.getTransactionID()));
 426         }
 427
 428         ReadyTransactionReply readyTransactionReply = new ReadyTransactionReply(
 429                 Serialization.serializedActorPath(replyActorPath));
 430         getSender().tell(ready.isReturnSerialized() ? readyTransactionReply.toSerializable() :
 431                 readyTransactionReply, getSelf());
 432     }
 433
 434     private void handleAbortTransaction(final AbortTransaction abort) {
 435         doAbortTransaction(abort.getTransactionID(), getSender());
 436     }
 437
 438     void doAbortTransaction(final String transactionID, final ActorRef sender) {
 439         final CohortEntry cohortEntry = commitCoordinator.getCohortEntryIfCurrent(transactionID);
 440         if(cohortEntry != null) {
 441             LOG.debug("{}: Aborting transaction {}", persistenceId(), transactionID);
 442
 443             // We don't remove the cached cohort entry here (ie pass false) in case the Tx was
 444             // aborted during replication in which case we may still commit locally if replication
 445             // succeeds.
 446             commitCoordinator.currentTransactionComplete(transactionID, false);
 447
 448             final ListenableFuture<Void> future = cohortEntry.getCohort().abort();
 449             final ActorRef self = getSelf();
 450
 451             Futures.addCallback(future, new FutureCallback<Void>() {
 452                 @Override
 453                 public void onSuccess(final Void v) {
 454                     shardMBean.incrementAbortTransactionsCount();
 455
 456                     if(sender != null) {
 457                         sender.tell(AbortTransactionReply.INSTANCE.toSerializable(), self);
 458                     }
 459                 }
 460
 461                 @Override
 462                 public void onFailure(final Throwable t) {
 463                     LOG.error("{}: An exception happened during abort", persistenceId(), t);
 464
 465                     if(sender != null) {
 466                         sender.tell(new akka.actor.Status.Failure(t), self);
 467                     }
 468                 }
 469             });
 470         }
 471     }
 472
 473     private void handleCreateTransaction(final Object message) {
 474         if (isLeader()) {
 475             createTransaction(CreateTransaction.fromSerializable(message));
 476         } else if (getLeader() != null) {
 477             getLeader().forward(message, getContext());
 478         } else {
 479             getSender().tell(new akka.actor.Status.Failure(new NoShardLeaderException(String.format(
 480                 "Could not find leader for shard %s so transaction cannot be created. This typically happens" +
 481                 " when the system is coming up or recovering and a leader is being elected. Try again" +
 482                 " later.", persistenceId()))), getSelf());
 483         }
 484     }
 485
 486     private void closeTransactionChain(final CloseTransactionChain closeTransactionChain) {
 487         DOMStoreTransactionChain chain =
 488             transactionChains.remove(closeTransactionChain.getTransactionChainId());
 489
 490         if(chain != null) {
 491             chain.close();
 492         }
 493     }
 494
 495     private ActorRef createTypedTransactionActor(int transactionType,
 496             ShardTransactionIdentifier transactionId, String transactionChainId,
 497             short clientVersion ) {
 498
 499         DOMStoreTransactionFactory factory = store;
 500
 501         if(!transactionChainId.isEmpty()) {
 502             factory = transactionChains.get(transactionChainId);
 503             if(factory == null){
 504                 DOMStoreTransactionChain transactionChain = store.createTransactionChain();
 505                 transactionChains.put(transactionChainId, transactionChain);
 506                 factory = transactionChain;
 507             }
 508         }
 509
 510         if(this.schemaContext == null) {
 511             throw new IllegalStateException("SchemaContext is not set");
 512         }
 513
 514         if (transactionType == TransactionProxy.TransactionType.READ_ONLY.ordinal()) {
 515
 516             shardMBean.incrementReadOnlyTransactionCount();
 517
 518             return getContext().actorOf(
 519                 ShardTransaction.props(factory.newReadOnlyTransaction(), getSelf(),
 520                         schemaContext, datastoreContext, shardMBean,
 521                         transactionId.getRemoteTransactionId(), clientVersion),
 522                         transactionId.toString());
 523
 524         } else if (transactionType == TransactionProxy.TransactionType.READ_WRITE.ordinal()) {
 525
 526             shardMBean.incrementReadWriteTransactionCount();
 527
 528             return getContext().actorOf(
 529                 ShardTransaction.props(factory.newReadWriteTransaction(), getSelf(),
 530                         schemaContext, datastoreContext, shardMBean,
 531                         transactionId.getRemoteTransactionId(), clientVersion),
 532                         transactionId.toString());
 533
 534
 535         } else if (transactionType == TransactionProxy.TransactionType.WRITE_ONLY.ordinal()) {
 536
 537             shardMBean.incrementWriteOnlyTransactionCount();
 538
 539             return getContext().actorOf(
 540                 ShardTransaction.props(factory.newWriteOnlyTransaction(), getSelf(),
 541                         schemaContext, datastoreContext, shardMBean,
 542                         transactionId.getRemoteTransactionId(), clientVersion),
 543                         transactionId.toString());
 544         } else {
 545             throw new IllegalArgumentException(
 546                 "Shard="+name + ":CreateTransaction message has unidentified transaction type="
 547                     + transactionType);
 548         }
 549     }
 550
 551     private void createTransaction(CreateTransaction createTransaction) {
 552         try {
 553             ActorRef transactionActor = createTransaction(createTransaction.getTransactionType(),
 554                 createTransaction.getTransactionId(), createTransaction.getTransactionChainId(),
 555                 createTransaction.getVersion());
 556
 557             getSender().tell(new CreateTransactionReply(Serialization.serializedActorPath(transactionActor),
 558                     createTransaction.getTransactionId()).toSerializable(), getSelf());
 559         } catch (Exception e) {
 560             getSender().tell(new akka.actor.Status.Failure(e), getSelf());
 561         }
 562     }
 563
 564     private ActorRef createTransaction(int transactionType, String remoteTransactionId,
 565             String transactionChainId, short clientVersion) {
 566
 567         ShardTransactionIdentifier transactionId =
 568             ShardTransactionIdentifier.builder()
 569                 .remoteTransactionId(remoteTransactionId)
 570                 .build();
 571
 572         if(LOG.isDebugEnabled()) {
 573             LOG.debug("{}: Creating transaction : {} ", persistenceId(), transactionId);
 574         }
 575
 576         ActorRef transactionActor = createTypedTransactionActor(transactionType, transactionId,
 577                 transactionChainId, clientVersion);
 578
 579         return transactionActor;
 580     }
 581
 582     private void syncCommitTransaction(final DOMStoreWriteTransaction transaction)
 583         throws ExecutionException, InterruptedException {
 584         DOMStoreThreePhaseCommitCohort commitCohort = transaction.ready();
 585         commitCohort.preCommit().get();
 586         commitCohort.commit().get();
 587     }
 588
 589     private void commitWithNewTransaction(final Modification modification) {
 590         DOMStoreWriteTransaction tx = store.newWriteOnlyTransaction();
 591         modification.apply(tx);
 592         try {
 593             syncCommitTransaction(tx);
 594             shardMBean.incrementCommittedTransactionCount();
 595             shardMBean.setLastCommittedTransactionTime(System.currentTimeMillis());
 596         } catch (InterruptedException | ExecutionException e) {
 597             shardMBean.incrementFailedTransactionsCount();
 598             LOG.error("{}: Failed to commit", persistenceId(), e);
 599         }
 600     }
 601
 602     private void updateSchemaContext(final UpdateSchemaContext message) {
 603         this.schemaContext = message.getSchemaContext();
 604         updateSchemaContext(message.getSchemaContext());
 605         store.onGlobalContextUpdated(message.getSchemaContext());
 606     }
 607
 608     @VisibleForTesting
 609     void updateSchemaContext(final SchemaContext schemaContext) {
 610         store.onGlobalContextUpdated(schemaContext);
 611     }
 612
 613     private void registerChangeListener(final RegisterChangeListener registerChangeListener) {
 614
 615         LOG.debug("{}: registerDataChangeListener for {}", persistenceId(), registerChangeListener.getPath());
 616
 617         ListenerRegistration<AsyncDataChangeListener<YangInstanceIdentifier,
 618                                                      NormalizedNode<?, ?>>> registration;
 619         if(isLeader()) {
 620             registration = doChangeListenerRegistration(registerChangeListener);
 621         } else {
 622             LOG.debug("{}: Shard is not the leader - delaying registration", persistenceId());
 623
 624             DelayedListenerRegistration delayedReg =
 625                     new DelayedListenerRegistration(registerChangeListener);
 626             delayedListenerRegistrations.add(delayedReg);
 627             registration = delayedReg;
 628         }
 629
 630         ActorRef listenerRegistration = getContext().actorOf(
 631                 DataChangeListenerRegistration.props(registration));
 632
 633         LOG.debug("{}: registerDataChangeListener sending reply, listenerRegistrationPath = {} ",
 634                 persistenceId(), listenerRegistration.path());
 635
 636         getSender().tell(new RegisterChangeListenerReply(listenerRegistration.path()), getSelf());
 637     }
 638
 639     private ListenerRegistration<AsyncDataChangeListener<YangInstanceIdentifier,
 640                                                NormalizedNode<?, ?>>> doChangeListenerRegistration(
 641             final RegisterChangeListener registerChangeListener) {
 642
 643         ActorSelection dataChangeListenerPath = getContext().system().actorSelection(
 644                 registerChangeListener.getDataChangeListenerPath());
 645
 646         // Notify the listener if notifications should be enabled or not
 647         // If this shard is the leader then it will enable notifications else
 648         // it will not
 649         dataChangeListenerPath.tell(new EnableNotification(true), getSelf());
 650
 651         // Now store a reference to the data change listener so it can be notified
 652         // at a later point if notifications should be enabled or disabled
 653         dataChangeListeners.add(dataChangeListenerPath);
 654
 655         AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>> listener =
 656                 new DataChangeListenerProxy(dataChangeListenerPath);
 657
 658         LOG.debug("{}: Registering for path {}", persistenceId(), registerChangeListener.getPath());
 659
 660         return store.registerChangeListener(registerChangeListener.getPath(), listener,
 661                 registerChangeListener.getScope());
 662     }
 663
 664     private boolean isMetricsCaptureEnabled(){
 665         CommonConfig config = new CommonConfig(getContext().system().settings().config());
 666         return config.isMetricCaptureEnabled();
 667     }
 668
 669     @Override
 670     protected
 671     void startLogRecoveryBatch(final int maxBatchSize) {
 672         currentLogRecoveryBatch = Lists.newArrayListWithCapacity(maxBatchSize);
 673
 674         if(LOG.isDebugEnabled()) {
 675             LOG.debug("{}: starting log recovery batch with max size {}", persistenceId(), maxBatchSize);
 676         }
 677     }
 678
 679     @Override
 680     protected void appendRecoveredLogEntry(final Payload data) {
 681         if(data instanceof ModificationPayload) {
 682             try {
 683                 currentLogRecoveryBatch.add(((ModificationPayload) data).getModification());
 684             } catch (ClassNotFoundException | IOException e) {
 685                 LOG.error("{}: Error extracting ModificationPayload", persistenceId(), e);
 686             }
 687         } else if (data instanceof CompositeModificationPayload) {
 688             currentLogRecoveryBatch.add(((CompositeModificationPayload) data).getModification());
 689         } else if (data instanceof CompositeModificationByteStringPayload) {
 690             currentLogRecoveryBatch.add(((CompositeModificationByteStringPayload) data).getModification());
 691         } else {
 692             LOG.error("{}: Unknown state received {} during recovery", persistenceId(), data);
 693         }
 694     }
 695
 696     @Override
 697     protected void applyRecoverySnapshot(final byte[] snapshotBytes) {
 698         if(recoveryCoordinator == null) {
 699             recoveryCoordinator = new ShardRecoveryCoordinator(persistenceId(), schemaContext,
 700                     LOG, name.toString());
 701         }
 702
 703         recoveryCoordinator.submit(snapshotBytes, store.newWriteOnlyTransaction());
 704
 705         if(LOG.isDebugEnabled()) {
 706             LOG.debug("{}: submitted recovery sbapshot", persistenceId());
 707         }
 708     }
 709
 710     @Override
 711     protected void applyCurrentLogRecoveryBatch() {
 712         if(recoveryCoordinator == null) {
 713             recoveryCoordinator = new ShardRecoveryCoordinator(persistenceId(), schemaContext,
 714                     LOG, name.toString());
 715         }
 716
 717         recoveryCoordinator.submit(currentLogRecoveryBatch, store.newWriteOnlyTransaction());
 718
 719         if(LOG.isDebugEnabled()) {
 720             LOG.debug("{}: submitted log recovery batch with size {}", persistenceId(),
 721                     currentLogRecoveryBatch.size());
 722         }
 723     }
 724
 725     @Override
 726     protected void onRecoveryComplete() {
 727         if(recoveryCoordinator != null) {
 728             Collection<DOMStoreWriteTransaction> txList = recoveryCoordinator.getTransactions();
 729
 730             if(LOG.isDebugEnabled()) {
 731                 LOG.debug("{}: recovery complete - committing {} Tx's", persistenceId(), txList.size());
 732             }
 733
 734             for(DOMStoreWriteTransaction tx: txList) {
 735                 try {
 736                     syncCommitTransaction(tx);
 737                     shardMBean.incrementCommittedTransactionCount();
 738                 } catch (InterruptedException | ExecutionException e) {
 739                     shardMBean.incrementFailedTransactionsCount();
 740                     LOG.error("{}: Failed to commit", persistenceId(), e);
 741                 }
 742             }
 743         }
 744
 745         recoveryCoordinator = null;
 746         currentLogRecoveryBatch = null;
 747         updateJournalStats();
 748
 749         //notify shard manager
 750         getContext().parent().tell(new ActorInitialized(), getSelf());
 751
 752         // Being paranoid here - this method should only be called once but just in case...
 753         if(txCommitTimeoutCheckSchedule == null) {
 754             // Schedule a message to be periodically sent to check if the current in-progress
 755             // transaction should be expired and aborted.
 756             FiniteDuration period = Duration.create(transactionCommitTimeout / 3, TimeUnit.MILLISECONDS);
 757             txCommitTimeoutCheckSchedule = getContext().system().scheduler().schedule(
 758                     period, period, getSelf(),
 759                     TX_COMMIT_TIMEOUT_CHECK_MESSAGE, getContext().dispatcher(), ActorRef.noSender());
 760         }
 761     }
 762
 763     @Override
 764     protected void applyState(final ActorRef clientActor, final String identifier, final Object data) {
 765
 766         if(data instanceof ModificationPayload) {
 767             try {
 768                 applyModificationToState(clientActor, identifier, ((ModificationPayload) data).getModification());
 769             } catch (ClassNotFoundException | IOException e) {
 770                 LOG.error("{}: Error extracting ModificationPayload", persistenceId(), e);
 771             }
 772         }
 773         else if (data instanceof CompositeModificationPayload) {
 774             Object modification = ((CompositeModificationPayload) data).getModification();
 775
 776             applyModificationToState(clientActor, identifier, modification);
 777         } else if(data instanceof CompositeModificationByteStringPayload ){
 778             Object modification = ((CompositeModificationByteStringPayload) data).getModification();
 779
 780             applyModificationToState(clientActor, identifier, modification);
 781         } else {
 782             LOG.error("{}: Unknown state received {} Class loader = {} CompositeNodeMod.ClassLoader = {}",
 783                     persistenceId(), data, data.getClass().getClassLoader(),
 784                     CompositeModificationPayload.class.getClassLoader());
 785         }
 786
 787         updateJournalStats();
 788
 789     }
 790
 791     private void applyModificationToState(ActorRef clientActor, String identifier, Object modification) {
 792         if(modification == null) {
 793             LOG.error(
 794                     "{}: modification is null - this is very unexpected, clientActor = {}, identifier = {}",
 795                     persistenceId(), identifier, clientActor != null ? clientActor.path().toString() : null);
 796         } else if(clientActor == null) {
 797             // There's no clientActor to which to send a commit reply so we must be applying
 798             // replicated state from the leader.
 799             commitWithNewTransaction(MutableCompositeModification.fromSerializable(modification));
 800         } else {
 801             // This must be the OK to commit after replication consensus.
 802             finishCommit(clientActor, identifier);
 803         }
 804     }
 805
 806     private void updateJournalStats() {
 807         ReplicatedLogEntry lastLogEntry = getLastLogEntry();
 808
 809         if (lastLogEntry != null) {
 810             shardMBean.setLastLogIndex(lastLogEntry.getIndex());
 811             shardMBean.setLastLogTerm(lastLogEntry.getTerm());
 812         }
 813
 814         shardMBean.setCommitIndex(getCommitIndex());
 815         shardMBean.setLastApplied(getLastApplied());
 816         shardMBean.setInMemoryJournalDataSize(getRaftActorContext().getReplicatedLog().dataSize());
 817     }
 818
 819     @Override
 820     protected void createSnapshot() {
 821         // Create a transaction actor. We are really going to treat the transaction as a worker
 822         // so that this actor does not get block building the snapshot. THe transaction actor will
 823         // after processing the CreateSnapshot message.
 824
 825         ActorRef createSnapshotTransaction = createTransaction(
 826                 TransactionProxy.TransactionType.READ_ONLY.ordinal(),
 827                 "createSnapshot" + ++createSnapshotTransactionCounter, "",
 828                 DataStoreVersions.CURRENT_VERSION);
 829
 830         createSnapshotTransaction.tell(CreateSnapshot.INSTANCE, self());
 831     }
 832
 833     @VisibleForTesting
 834     @Override
 835     protected void applySnapshot(final byte[] snapshotBytes) {
 836         // Since this will be done only on Recovery or when this actor is a Follower
 837         // we can safely commit everything in here. We not need to worry about event notifications
 838         // as they would have already been disabled on the follower
 839
 840         LOG.info("{}: Applying snapshot", persistenceId());
 841         try {
 842             DOMStoreWriteTransaction transaction = store.newWriteOnlyTransaction();
 843
 844             NormalizedNode<?, ?> node = SerializationUtils.deserializeNormalizedNode(snapshotBytes);
 845
 846             // delete everything first
 847             transaction.delete(DATASTORE_ROOT);
 848
 849             // Add everything from the remote node back
 850             transaction.write(DATASTORE_ROOT, node);
 851             syncCommitTransaction(transaction);
 852         } catch (InterruptedException | ExecutionException e) {
 853             LOG.error("{}: An exception occurred when applying snapshot", persistenceId(), e);
 854         } finally {
 855             LOG.info("{}: Done applying snapshot", persistenceId());
 856         }
 857     }
 858
 859     @Override
 860     protected void onStateChanged() {
 861         boolean isLeader = isLeader();
 862         for (ActorSelection dataChangeListener : dataChangeListeners) {
 863             dataChangeListener.tell(new EnableNotification(isLeader), getSelf());
 864         }
 865
 866         if(isLeader) {
 867             for(DelayedListenerRegistration reg: delayedListenerRegistrations) {
 868                 if(!reg.isClosed()) {
 869                     reg.setDelegate(doChangeListenerRegistration(reg.getRegisterChangeListener()));
 870                 }
 871             }
 872
 873             delayedListenerRegistrations.clear();
 874         }
 875
 876         shardMBean.setRaftState(getRaftState().name());
 877         shardMBean.setCurrentTerm(getCurrentTerm());
 878
 879         // If this actor is no longer the leader close all the transaction chains
 880         if(!isLeader){
 881             for(Map.Entry<String, DOMStoreTransactionChain> entry : transactionChains.entrySet()){
 882                 if(LOG.isDebugEnabled()) {
 883                     LOG.debug(
 884                         "{}: onStateChanged: Closing transaction chain {} because shard {} is no longer the leader",
 885                         persistenceId(), entry.getKey(), getId());
 886                 }
 887                 entry.getValue().close();
 888             }
 889
 890             transactionChains.clear();
 891         }
 892     }
 893
 894     @Override
 895     protected DataPersistenceProvider persistence() {
 896         return dataPersistenceProvider;
 897     }
 898
 899     @Override protected void onLeaderChanged(final String oldLeader, final String newLeader) {
 900         shardMBean.setLeader(newLeader);
 901     }
 902
 903     @Override public String persistenceId() {
 904         return this.name.toString();
 905     }
 906
 907     @VisibleForTesting
 908     DataPersistenceProvider getDataPersistenceProvider() {
 909         return dataPersistenceProvider;
 910     }
 911
 912     private static class ShardCreator implements Creator<Shard> {
 913
 914         private static final long serialVersionUID = 1L;
 915
 916         final ShardIdentifier name;
 917         final Map<ShardIdentifier, String> peerAddresses;
 918         final DatastoreContext datastoreContext;
 919         final SchemaContext schemaContext;
 920
 921         ShardCreator(final ShardIdentifier name, final Map<ShardIdentifier, String> peerAddresses,
 922                 final DatastoreContext datastoreContext, final SchemaContext schemaContext) {
 923             this.name = name;
 924             this.peerAddresses = peerAddresses;
 925             this.datastoreContext = datastoreContext;
 926             this.schemaContext = schemaContext;
 927         }
 928
 929         @Override
 930         public Shard create() throws Exception {
 931             return new Shard(name, peerAddresses, datastoreContext, schemaContext);
 932         }
 933     }
 934
 935     @VisibleForTesting
 936     InMemoryDOMDataStore getDataStore() {
 937         return store;
 938     }
 939
 940     @VisibleForTesting
 941     ShardStats getShardMBean() {
 942         return shardMBean;
 943     }
 944
 945     private static class DelayedListenerRegistration implements
 946         ListenerRegistration<AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>>> {
 947
 948         private volatile boolean closed;
 949
 950         private final RegisterChangeListener registerChangeListener;
 951
 952         private volatile ListenerRegistration<AsyncDataChangeListener<YangInstanceIdentifier,
 953                                                              NormalizedNode<?, ?>>> delegate;
 954
 955         DelayedListenerRegistration(final RegisterChangeListener registerChangeListener) {
 956             this.registerChangeListener = registerChangeListener;
 957         }
 958
 959         void setDelegate( final ListenerRegistration<AsyncDataChangeListener<YangInstanceIdentifier,
 960                                             NormalizedNode<?, ?>>> registration) {
 961             this.delegate = registration;
 962         }
 963
 964         boolean isClosed() {
 965             return closed;
 966         }
 967
 968         RegisterChangeListener getRegisterChangeListener() {
 969             return registerChangeListener;
 970         }
 971
 972         @Override
 973         public AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>> getInstance() {
 974             return delegate != null ? delegate.getInstance() : null;
 975         }
 976
 977         @Override
 978         public void close() {
 979             closed = true;
 980             if(delegate != null) {
 981                 delegate.close();
 982             }
 983         }
 984     }
 985 }