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