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