opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/Shard.java

   1 /*
   2  * Copyright (c) 2014 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8
   9 package org.opendaylight.controller.cluster.datastore;
  10
  11 import akka.actor.ActorRef;
  12 import akka.actor.ActorSelection;
  13 import akka.actor.Cancellable;
  14 import akka.actor.Props;
  15 import akka.japi.Creator;
  16 import akka.persistence.RecoveryFailure;
  17 import akka.serialization.Serialization;
  18 import com.google.common.annotations.VisibleForTesting;
  19 import com.google.common.base.Optional;
  20 import com.google.common.base.Preconditions;
  21 import com.google.common.collect.Lists;
  22 import com.google.common.util.concurrent.FutureCallback;
  23 import com.google.common.util.concurrent.Futures;
  24 import com.google.common.util.concurrent.ListenableFuture;
  25 import java.io.IOException;
  26 import java.util.Collection;
  27 import java.util.HashMap;
  28 import java.util.List;
  29 import java.util.Map;
  30 import java.util.concurrent.ExecutionException;
  31 import java.util.concurrent.TimeUnit;
  32 import javax.annotation.Nonnull;
  33 import org.opendaylight.controller.cluster.DataPersistenceProvider;
  34 import org.opendaylight.controller.cluster.common.actor.CommonConfig;
  35 import org.opendaylight.controller.cluster.common.actor.MeteringBehavior;
  36 import org.opendaylight.controller.cluster.datastore.ShardCommitCoordinator.CohortEntry;
  37 import org.opendaylight.controller.cluster.datastore.compat.BackwardsCompatibleThreePhaseCommitCohort;
  38 import org.opendaylight.controller.cluster.datastore.exceptions.NoShardLeaderException;
  39 import org.opendaylight.controller.cluster.datastore.identifiers.ShardIdentifier;
  40 import org.opendaylight.controller.cluster.datastore.identifiers.ShardTransactionIdentifier;
  41 import org.opendaylight.controller.cluster.datastore.jmx.mbeans.shard.ShardMBeanFactory;
  42 import org.opendaylight.controller.cluster.datastore.jmx.mbeans.shard.ShardStats;
  43 import org.opendaylight.controller.cluster.datastore.messages.AbortTransaction;
  44 import org.opendaylight.controller.cluster.datastore.messages.AbortTransactionReply;
  45 import org.opendaylight.controller.cluster.datastore.messages.ActorInitialized;
  46 import org.opendaylight.controller.cluster.datastore.messages.CanCommitTransaction;
  47 import org.opendaylight.controller.cluster.datastore.messages.CloseTransactionChain;
  48 import org.opendaylight.controller.cluster.datastore.messages.CommitTransaction;
  49 import org.opendaylight.controller.cluster.datastore.messages.CommitTransactionReply;
  50 import org.opendaylight.controller.cluster.datastore.messages.CreateSnapshot;
  51 import org.opendaylight.controller.cluster.datastore.messages.CreateTransaction;
  52 import org.opendaylight.controller.cluster.datastore.messages.CreateTransactionReply;
  53 import org.opendaylight.controller.cluster.datastore.messages.EnableNotification;
  54 import org.opendaylight.controller.cluster.datastore.messages.ForwardedReadyTransaction;
  55 import org.opendaylight.controller.cluster.datastore.messages.PeerAddressResolved;
  56 import org.opendaylight.controller.cluster.datastore.messages.ReadyTransactionReply;
  57 import org.opendaylight.controller.cluster.datastore.messages.RegisterChangeListener;
  58 import org.opendaylight.controller.cluster.datastore.messages.RegisterChangeListenerReply;
  59 import org.opendaylight.controller.cluster.datastore.messages.UpdateSchemaContext;
  60 import org.opendaylight.controller.cluster.datastore.modification.Modification;
  61 import org.opendaylight.controller.cluster.datastore.modification.ModificationPayload;
  62 import org.opendaylight.controller.cluster.datastore.modification.MutableCompositeModification;
  63 import org.opendaylight.controller.cluster.datastore.utils.Dispatchers;
  64 import org.opendaylight.controller.cluster.datastore.utils.MessageTracker;
  65 import org.opendaylight.controller.cluster.datastore.utils.SerializationUtils;
  66 import org.opendaylight.controller.cluster.notifications.RegisterRoleChangeListener;
  67 import org.opendaylight.controller.cluster.notifications.RoleChangeNotifier;
  68 import org.opendaylight.controller.cluster.raft.RaftActor;
  69 import org.opendaylight.controller.cluster.raft.base.messages.FollowerInitialSyncUpStatus;
  70 import org.opendaylight.controller.cluster.raft.messages.AppendEntriesReply;
  71 import org.opendaylight.controller.cluster.raft.protobuff.client.messages.CompositeModificationByteStringPayload;
  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.sal.core.spi.data.DOMStoreThreePhaseCommitCohort;
  78 import org.opendaylight.controller.sal.core.spi.data.DOMStoreTransaction;
  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 YangInstanceIdentifier DATASTORE_ROOT = YangInstanceIdentifier.builder().build();
  98
  99     private static final Object TX_COMMIT_TIMEOUT_CHECK_MESSAGE = "txCommitTimeoutCheck";
 100
 101     @VisibleForTesting
 102     static final String DEFAULT_NAME = "default";
 103
 104     // The state of this Shard
 105     private final InMemoryDOMDataStore store;
 106
 107     /// The name of this shard
 108     private final ShardIdentifier name;
 109
 110     private final ShardStats shardMBean;
 111
 112     private final List<ActorSelection> dataChangeListeners =  Lists.newArrayList();
 113
 114     private final List<DelayedListenerRegistration> delayedListenerRegistrations =
 115                                                                        Lists.newArrayList();
 116
 117     private DatastoreContext datastoreContext;
 118
 119     private DataPersistenceProvider dataPersistenceProvider;
 120
 121     private SchemaContext schemaContext;
 122
 123     private int createSnapshotTransactionCounter;
 124
 125     private final ShardCommitCoordinator commitCoordinator;
 126
 127     private long transactionCommitTimeout;
 128
 129     private Cancellable txCommitTimeoutCheckSchedule;
 130
 131     private final Optional<ActorRef> roleChangeNotifier;
 132
 133     private final MessageTracker appendEntriesReplyTracker;
 134
 135     private final ReadyTransactionReply READY_TRANSACTION_REPLY = new ReadyTransactionReply(
 136             Serialization.serializedActorPath(getSelf()));
 137
 138
 139     /**
 140      * Coordinates persistence recovery on startup.
 141      */
 142     private ShardRecoveryCoordinator recoveryCoordinator;
 143     private List<Object> currentLogRecoveryBatch;
 144
 145     private final Map<String, DOMStoreTransactionChain> transactionChains = new HashMap<>();
 146
 147     private final String txnDispatcherPath;
 148
 149     protected Shard(final ShardIdentifier name, final Map<ShardIdentifier, String> peerAddresses,
 150             final DatastoreContext datastoreContext, final SchemaContext schemaContext) {
 151         super(name.toString(), mapPeerAddresses(peerAddresses),
 152                 Optional.of(datastoreContext.getShardRaftConfig()));
 153
 154         this.name = name;
 155         this.datastoreContext = datastoreContext;
 156         this.schemaContext = schemaContext;
 157         this.dataPersistenceProvider = (datastoreContext.isPersistent())
 158                 ? new PersistentDataProvider() : new NonPersistentRaftDataProvider();
 159         this.txnDispatcherPath = new Dispatchers(context().system().dispatchers())
 160                 .getDispatcherPath(Dispatchers.DispatcherType.Transaction);
 161
 162
 163         LOG.info("Shard created : {}, persistent : {}", name, datastoreContext.isPersistent());
 164
 165         store = InMemoryDOMDataStoreFactory.create(name.toString(), null,
 166                 datastoreContext.getDataStoreProperties());
 167
 168         if(schemaContext != null) {
 169             store.onGlobalContextUpdated(schemaContext);
 170         }
 171
 172         shardMBean = ShardMBeanFactory.getShardStatsMBean(name.toString(),
 173                 datastoreContext.getDataStoreMXBeanType());
 174         shardMBean.setNotificationManager(store.getDataChangeListenerNotificationManager());
 175         shardMBean.setShardActor(getSelf());
 176
 177         if (isMetricsCaptureEnabled()) {
 178             getContext().become(new MeteringBehavior(this));
 179         }
 180
 181         commitCoordinator = new ShardCommitCoordinator(TimeUnit.SECONDS.convert(1, TimeUnit.MINUTES),
 182                 datastoreContext.getShardTransactionCommitQueueCapacity(), LOG, name.toString());
 183
 184         setTransactionCommitTimeout();
 185
 186         // create a notifier actor for each cluster member
 187         roleChangeNotifier = createRoleChangeNotifier(name.toString());
 188
 189         appendEntriesReplyTracker = new MessageTracker(AppendEntriesReply.class,
 190                 getRaftActorContext().getConfigParams().getIsolatedCheckIntervalInMillis());
 191     }
 192
 193     private void setTransactionCommitTimeout() {
 194         transactionCommitTimeout = TimeUnit.MILLISECONDS.convert(
 195                 datastoreContext.getShardTransactionCommitTimeoutInSeconds(), TimeUnit.SECONDS);
 196     }
 197
 198     private static Map<String, String> mapPeerAddresses(
 199         final Map<ShardIdentifier, String> peerAddresses) {
 200         Map<String, String> map = new HashMap<>();
 201
 202         for (Map.Entry<ShardIdentifier, String> entry : peerAddresses
 203             .entrySet()) {
 204             map.put(entry.getKey().toString(), entry.getValue());
 205         }
 206
 207         return map;
 208     }
 209
 210     public static Props props(final ShardIdentifier name,
 211         final Map<ShardIdentifier, String> peerAddresses,
 212         final DatastoreContext datastoreContext, final SchemaContext schemaContext) {
 213         Preconditions.checkNotNull(name, "name should not be null");
 214         Preconditions.checkNotNull(peerAddresses, "peerAddresses should not be null");
 215         Preconditions.checkNotNull(datastoreContext, "dataStoreContext should not be null");
 216         Preconditions.checkNotNull(schemaContext, "schemaContext should not be null");
 217
 218         return Props.create(new ShardCreator(name, peerAddresses, datastoreContext, schemaContext));
 219     }
 220
 221     private Optional<ActorRef> createRoleChangeNotifier(String shardId) {
 222         ActorRef shardRoleChangeNotifier = this.getContext().actorOf(
 223             RoleChangeNotifier.getProps(shardId), shardId + "-notifier");
 224         return Optional.of(shardRoleChangeNotifier);
 225     }
 226
 227     @Override
 228     public void postStop() {
 229         LOG.info("Stopping Shard {}", persistenceId());
 230
 231         super.postStop();
 232
 233         if(txCommitTimeoutCheckSchedule != null) {
 234             txCommitTimeoutCheckSchedule.cancel();
 235         }
 236
 237         shardMBean.unregisterMBean();
 238     }
 239
 240     @Override
 241     public void onReceiveRecover(final Object message) throws Exception {
 242         if(LOG.isDebugEnabled()) {
 243             LOG.debug("{}: onReceiveRecover: Received message {} from {}", persistenceId(),
 244                 message.getClass().toString(), getSender());
 245         }
 246
 247         if (message instanceof RecoveryFailure){
 248             LOG.error("{}: Recovery failed because of this cause",
 249                     persistenceId(), ((RecoveryFailure) message).cause());
 250
 251             // Even though recovery failed, we still need to finish our recovery, eg send the
 252             // ActorInitialized message and start the txCommitTimeoutCheckSchedule.
 253             onRecoveryComplete();
 254         } else {
 255             super.onReceiveRecover(message);
 256             if(LOG.isTraceEnabled()) {
 257                 appendEntriesReplyTracker.begin();
 258             }
 259         }
 260     }
 261
 262     @Override
 263     public void onReceiveCommand(final Object message) throws Exception {
 264
 265         MessageTracker.Context context = appendEntriesReplyTracker.received(message);
 266
 267         if(context.error().isPresent()){
 268             LOG.trace("{} : AppendEntriesReply failed to arrive at the expected interval {}", persistenceId(),
 269                     context.error());
 270         }
 271
 272         try {
 273             if (CreateTransaction.SERIALIZABLE_CLASS.isInstance(message)) {
 274                 handleCreateTransaction(message);
 275             } else if (message instanceof ForwardedReadyTransaction) {
 276                 handleForwardedReadyTransaction((ForwardedReadyTransaction) message);
 277             } else if (CanCommitTransaction.SERIALIZABLE_CLASS.isInstance(message)) {
 278                 handleCanCommitTransaction(CanCommitTransaction.fromSerializable(message));
 279             } else if (CommitTransaction.SERIALIZABLE_CLASS.isInstance(message)) {
 280                 handleCommitTransaction(CommitTransaction.fromSerializable(message));
 281             } else if (AbortTransaction.SERIALIZABLE_CLASS.isInstance(message)) {
 282                 handleAbortTransaction(AbortTransaction.fromSerializable(message));
 283             } else if (CloseTransactionChain.SERIALIZABLE_CLASS.isInstance(message)) {
 284                 closeTransactionChain(CloseTransactionChain.fromSerializable(message));
 285             } else if (message instanceof RegisterChangeListener) {
 286                 registerChangeListener((RegisterChangeListener) message);
 287             } else if (message instanceof UpdateSchemaContext) {
 288                 updateSchemaContext((UpdateSchemaContext) message);
 289             } else if (message instanceof PeerAddressResolved) {
 290                 PeerAddressResolved resolved = (PeerAddressResolved) message;
 291                 setPeerAddress(resolved.getPeerId().toString(),
 292                         resolved.getPeerAddress());
 293             } else if (message.equals(TX_COMMIT_TIMEOUT_CHECK_MESSAGE)) {
 294                 handleTransactionCommitTimeoutCheck();
 295             } else if(message instanceof DatastoreContext) {
 296                 onDatastoreContext((DatastoreContext)message);
 297             } else if(message instanceof RegisterRoleChangeListener){
 298                 roleChangeNotifier.get().forward(message, context());
 299             } else if (message instanceof FollowerInitialSyncUpStatus){
 300                 shardMBean.setFollowerInitialSyncStatus(((FollowerInitialSyncUpStatus) message).isInitialSyncDone());
 301                 context().parent().tell(message, self());
 302             } else {
 303                 super.onReceiveCommand(message);
 304             }
 305         } finally {
 306             context.done();
 307         }
 308     }
 309
 310     @Override
 311     protected Optional<ActorRef> getRoleChangeNotifier() {
 312         return roleChangeNotifier;
 313     }
 314
 315     private void onDatastoreContext(DatastoreContext context) {
 316         datastoreContext = context;
 317
 318         commitCoordinator.setQueueCapacity(datastoreContext.getShardTransactionCommitQueueCapacity());
 319
 320         setTransactionCommitTimeout();
 321
 322         if(datastoreContext.isPersistent() &&
 323                 dataPersistenceProvider instanceof NonPersistentRaftDataProvider) {
 324             dataPersistenceProvider = new PersistentDataProvider();
 325         } else if(!datastoreContext.isPersistent() &&
 326                 dataPersistenceProvider instanceof PersistentDataProvider) {
 327             dataPersistenceProvider = new NonPersistentRaftDataProvider();
 328         }
 329
 330         updateConfigParams(datastoreContext.getShardRaftConfig());
 331     }
 332
 333     private void handleTransactionCommitTimeoutCheck() {
 334         CohortEntry cohortEntry = commitCoordinator.getCurrentCohortEntry();
 335         if(cohortEntry != null) {
 336             long elapsed = System.currentTimeMillis() - cohortEntry.getLastAccessTime();
 337             if(elapsed > transactionCommitTimeout) {
 338                 LOG.warn("{}: Current transaction {} has timed out after {} ms - aborting",
 339                         persistenceId(), cohortEntry.getTransactionID(), transactionCommitTimeout);
 340
 341                 doAbortTransaction(cohortEntry.getTransactionID(), null);
 342             }
 343         }
 344     }
 345
 346     private void handleCommitTransaction(final CommitTransaction commit) {
 347         final String transactionID = commit.getTransactionID();
 348
 349         LOG.debug("{}: Committing transaction {}", persistenceId(), transactionID);
 350
 351         // Get the current in-progress cohort entry in the commitCoordinator if it corresponds to
 352         // this transaction.
 353         final CohortEntry cohortEntry = commitCoordinator.getCohortEntryIfCurrent(transactionID);
 354         if(cohortEntry == null) {
 355             // We're not the current Tx - the Tx was likely expired b/c it took too long in
 356             // between the canCommit and commit messages.
 357             IllegalStateException ex = new IllegalStateException(
 358                     String.format("%s: Cannot commit transaction %s - it is not the current transaction",
 359                             persistenceId(), transactionID));
 360             LOG.error(ex.getMessage());
 361             shardMBean.incrementFailedTransactionsCount();
 362             getSender().tell(new akka.actor.Status.Failure(ex), getSelf());
 363             return;
 364         }
 365
 366         // We perform the preCommit phase here atomically with the commit phase. This is an
 367         // optimization to eliminate the overhead of an extra preCommit message. We lose front-end
 368         // coordination of preCommit across shards in case of failure but preCommit should not
 369         // normally fail since we ensure only one concurrent 3-phase commit.
 370
 371         try {
 372             // We block on the future here so we don't have to worry about possibly accessing our
 373             // state on a different thread outside of our dispatcher. Also, the data store
 374             // currently uses a same thread executor anyway.
 375             cohortEntry.getCohort().preCommit().get();
 376
 377             // If we do not have any followers and we are not using persistence
 378             // or if cohortEntry has no modifications
 379             // we can apply modification to the state immediately
 380             if((!hasFollowers() && !persistence().isRecoveryApplicable()) || (!cohortEntry.hasModifications())){
 381                 applyModificationToState(getSender(), transactionID, cohortEntry.getModification());
 382             } else {
 383                 Shard.this.persistData(getSender(), transactionID,
 384                         new ModificationPayload(cohortEntry.getModification()));
 385             }
 386         } catch (Exception e) {
 387             LOG.error("{} An exception occurred while preCommitting transaction {}",
 388                     persistenceId(), cohortEntry.getTransactionID(), e);
 389             shardMBean.incrementFailedTransactionsCount();
 390             getSender().tell(new akka.actor.Status.Failure(e), getSelf());
 391         }
 392
 393         cohortEntry.updateLastAccessTime();
 394     }
 395
 396     private void finishCommit(@Nonnull final ActorRef sender, final @Nonnull String transactionID) {
 397         // With persistence enabled, this method is called via applyState by the leader strategy
 398         // after the commit has been replicated to a majority of the followers.
 399
 400         CohortEntry cohortEntry = commitCoordinator.getCohortEntryIfCurrent(transactionID);
 401         if(cohortEntry == null) {
 402             // The transaction is no longer the current commit. This can happen if the transaction
 403             // was aborted prior, most likely due to timeout in the front-end. We need to finish
 404             // committing the transaction though since it was successfully persisted and replicated
 405             // however we can't use the original cohort b/c it was already preCommitted and may
 406             // conflict with the current commit or may have been aborted so we commit with a new
 407             // transaction.
 408             cohortEntry = commitCoordinator.getAndRemoveCohortEntry(transactionID);
 409             if(cohortEntry != null) {
 410                 commitWithNewTransaction(cohortEntry.getModification());
 411                 sender.tell(CommitTransactionReply.INSTANCE.toSerializable(), getSelf());
 412             } else {
 413                 // This really shouldn't happen - it likely means that persistence or replication
 414                 // took so long to complete such that the cohort entry was expired from the cache.
 415                 IllegalStateException ex = new IllegalStateException(
 416                         String.format("%s: Could not finish committing transaction %s - no CohortEntry found",
 417                                 persistenceId(), transactionID));
 418                 LOG.error(ex.getMessage());
 419                 sender.tell(new akka.actor.Status.Failure(ex), getSelf());
 420             }
 421
 422             return;
 423         }
 424
 425         LOG.debug("{}: Finishing commit for transaction {}", persistenceId(), cohortEntry.getTransactionID());
 426
 427         try {
 428             // We block on the future here so we don't have to worry about possibly accessing our
 429             // state on a different thread outside of our dispatcher. Also, the data store
 430             // currently uses a same thread executor anyway.
 431             cohortEntry.getCohort().commit().get();
 432
 433             sender.tell(CommitTransactionReply.INSTANCE.toSerializable(), getSelf());
 434
 435             shardMBean.incrementCommittedTransactionCount();
 436             shardMBean.setLastCommittedTransactionTime(System.currentTimeMillis());
 437
 438         } catch (Exception e) {
 439             sender.tell(new akka.actor.Status.Failure(e), getSelf());
 440
 441             LOG.error("{}, An exception occurred while committing transaction {}", persistenceId(),
 442                     transactionID, e);
 443             shardMBean.incrementFailedTransactionsCount();
 444         } finally {
 445             commitCoordinator.currentTransactionComplete(transactionID, true);
 446         }
 447     }
 448
 449     private void handleCanCommitTransaction(final CanCommitTransaction canCommit) {
 450         LOG.debug("{}: Can committing transaction {}", persistenceId(), canCommit.getTransactionID());
 451         commitCoordinator.handleCanCommit(canCommit, getSender(), self());
 452     }
 453
 454     private void handleForwardedReadyTransaction(ForwardedReadyTransaction ready) {
 455         LOG.debug("{}: Readying transaction {}, client version {}", persistenceId(),
 456                 ready.getTransactionID(), ready.getTxnClientVersion());
 457
 458         // This message is forwarded by the ShardTransaction on ready. We cache the cohort in the
 459         // commitCoordinator in preparation for the subsequent three phase commit initiated by
 460         // the front-end.
 461         commitCoordinator.transactionReady(ready.getTransactionID(), ready.getCohort(),
 462                 ready.getModification());
 463
 464         // Return our actor path as we'll handle the three phase commit, except if the Tx client
 465         // version < 1 (Helium-1 version). This means the Tx was initiated by a base Helium version
 466         // node. In that case, the subsequent 3-phase commit messages won't contain the
 467         // transactionId so to maintain backwards compatibility, we create a separate cohort actor
 468         // to provide the compatible behavior.
 469         if(ready.getTxnClientVersion() < DataStoreVersions.HELIUM_1_VERSION) {
 470             LOG.debug("{}: Creating BackwardsCompatibleThreePhaseCommitCohort", persistenceId());
 471             ActorRef replyActorPath = getContext().actorOf(BackwardsCompatibleThreePhaseCommitCohort.props(
 472                     ready.getTransactionID()));
 473
 474             ReadyTransactionReply readyTransactionReply =
 475                     new ReadyTransactionReply(Serialization.serializedActorPath(replyActorPath));
 476             getSender().tell(ready.isReturnSerialized() ? readyTransactionReply.toSerializable() :
 477                     readyTransactionReply, getSelf());
 478
 479         } else {
 480
 481             getSender().tell(ready.isReturnSerialized() ? READY_TRANSACTION_REPLY.toSerializable() :
 482                     READY_TRANSACTION_REPLY, getSelf());
 483         }
 484     }
 485
 486     private void handleAbortTransaction(final AbortTransaction abort) {
 487         doAbortTransaction(abort.getTransactionID(), getSender());
 488     }
 489
 490     void doAbortTransaction(final String transactionID, final ActorRef sender) {
 491         final CohortEntry cohortEntry = commitCoordinator.getCohortEntryIfCurrent(transactionID);
 492         if(cohortEntry != null) {
 493             LOG.debug("{}: Aborting transaction {}", persistenceId(), transactionID);
 494
 495             // We don't remove the cached cohort entry here (ie pass false) in case the Tx was
 496             // aborted during replication in which case we may still commit locally if replication
 497             // succeeds.
 498             commitCoordinator.currentTransactionComplete(transactionID, false);
 499
 500             final ListenableFuture<Void> future = cohortEntry.getCohort().abort();
 501             final ActorRef self = getSelf();
 502
 503             Futures.addCallback(future, new FutureCallback<Void>() {
 504                 @Override
 505                 public void onSuccess(final Void v) {
 506                     shardMBean.incrementAbortTransactionsCount();
 507
 508                     if(sender != null) {
 509                         sender.tell(AbortTransactionReply.INSTANCE.toSerializable(), self);
 510                     }
 511                 }
 512
 513                 @Override
 514                 public void onFailure(final Throwable t) {
 515                     LOG.error("{}: An exception happened during abort", persistenceId(), t);
 516
 517                     if(sender != null) {
 518                         sender.tell(new akka.actor.Status.Failure(t), self);
 519                     }
 520                 }
 521             });
 522         }
 523     }
 524
 525     private void handleCreateTransaction(final Object message) {
 526         if (isLeader()) {
 527             createTransaction(CreateTransaction.fromSerializable(message));
 528         } else if (getLeader() != null) {
 529             getLeader().forward(message, getContext());
 530         } else {
 531             getSender().tell(new akka.actor.Status.Failure(new NoShardLeaderException(String.format(
 532                 "Could not find leader for shard %s so transaction cannot be created. This typically happens" +
 533                 " when the system is coming up or recovering and a leader is being elected. Try again" +
 534                 " later.", persistenceId()))), getSelf());
 535         }
 536     }
 537
 538     private void closeTransactionChain(final CloseTransactionChain closeTransactionChain) {
 539         DOMStoreTransactionChain chain =
 540             transactionChains.remove(closeTransactionChain.getTransactionChainId());
 541
 542         if(chain != null) {
 543             chain.close();
 544         }
 545     }
 546
 547     private ActorRef createTypedTransactionActor(int transactionType,
 548             ShardTransactionIdentifier transactionId, String transactionChainId,
 549             short clientVersion ) {
 550
 551         DOMStoreTransactionFactory factory = store;
 552
 553         if(!transactionChainId.isEmpty()) {
 554             factory = transactionChains.get(transactionChainId);
 555             if(factory == null){
 556                 DOMStoreTransactionChain transactionChain = store.createTransactionChain();
 557                 transactionChains.put(transactionChainId, transactionChain);
 558                 factory = transactionChain;
 559             }
 560         }
 561
 562         if(this.schemaContext == null) {
 563             throw new IllegalStateException("SchemaContext is not set");
 564         }
 565
 566         if (transactionType == TransactionProxy.TransactionType.WRITE_ONLY.ordinal()) {
 567
 568             shardMBean.incrementWriteOnlyTransactionCount();
 569
 570             return createShardTransaction(factory.newWriteOnlyTransaction(), transactionId, clientVersion);
 571
 572         } else if (transactionType == TransactionProxy.TransactionType.READ_WRITE.ordinal()) {
 573
 574             shardMBean.incrementReadWriteTransactionCount();
 575
 576             return createShardTransaction(factory.newReadWriteTransaction(), transactionId, clientVersion);
 577
 578         } else if (transactionType == TransactionProxy.TransactionType.READ_ONLY.ordinal()) {
 579
 580             shardMBean.incrementReadOnlyTransactionCount();
 581
 582             return createShardTransaction(factory.newReadOnlyTransaction(), transactionId, clientVersion);
 583
 584         } else {
 585             throw new IllegalArgumentException(
 586                 "Shard="+name + ":CreateTransaction message has unidentified transaction type="
 587                     + transactionType);
 588         }
 589     }
 590
 591     private ActorRef createShardTransaction(DOMStoreTransaction transaction, ShardTransactionIdentifier transactionId,
 592                                             short clientVersion){
 593         return getContext().actorOf(
 594                 ShardTransaction.props(transaction, getSelf(),
 595                         schemaContext, datastoreContext, shardMBean,
 596                         transactionId.getRemoteTransactionId(), clientVersion)
 597                         .withDispatcher(txnDispatcherPath),
 598                 transactionId.toString());
 599
 600     }
 601
 602     private void createTransaction(CreateTransaction createTransaction) {
 603         try {
 604             ActorRef transactionActor = createTransaction(createTransaction.getTransactionType(),
 605                 createTransaction.getTransactionId(), createTransaction.getTransactionChainId(),
 606                 createTransaction.getVersion());
 607
 608             getSender().tell(new CreateTransactionReply(Serialization.serializedActorPath(transactionActor),
 609                     createTransaction.getTransactionId()).toSerializable(), getSelf());
 610         } catch (Exception e) {
 611             getSender().tell(new akka.actor.Status.Failure(e), getSelf());
 612         }
 613     }
 614
 615     private ActorRef createTransaction(int transactionType, String remoteTransactionId,
 616             String transactionChainId, short clientVersion) {
 617
 618
 619         ShardTransactionIdentifier transactionId = new ShardTransactionIdentifier(remoteTransactionId);
 620
 621         if(LOG.isDebugEnabled()) {
 622             LOG.debug("{}: Creating transaction : {} ", persistenceId(), transactionId);
 623         }
 624
 625         ActorRef transactionActor = createTypedTransactionActor(transactionType, transactionId,
 626                 transactionChainId, clientVersion);
 627
 628         return transactionActor;
 629     }
 630
 631     private void syncCommitTransaction(final DOMStoreWriteTransaction transaction)
 632         throws ExecutionException, InterruptedException {
 633         DOMStoreThreePhaseCommitCohort commitCohort = transaction.ready();
 634         commitCohort.preCommit().get();
 635         commitCohort.commit().get();
 636     }
 637
 638     private void commitWithNewTransaction(final Modification modification) {
 639         DOMStoreWriteTransaction tx = store.newWriteOnlyTransaction();
 640         modification.apply(tx);
 641         try {
 642             syncCommitTransaction(tx);
 643             shardMBean.incrementCommittedTransactionCount();
 644             shardMBean.setLastCommittedTransactionTime(System.currentTimeMillis());
 645         } catch (InterruptedException | ExecutionException e) {
 646             shardMBean.incrementFailedTransactionsCount();
 647             LOG.error("{}: Failed to commit", persistenceId(), e);
 648         }
 649     }
 650
 651     private void updateSchemaContext(final UpdateSchemaContext message) {
 652         this.schemaContext = message.getSchemaContext();
 653         updateSchemaContext(message.getSchemaContext());
 654         store.onGlobalContextUpdated(message.getSchemaContext());
 655     }
 656
 657     @VisibleForTesting
 658     void updateSchemaContext(final SchemaContext schemaContext) {
 659         store.onGlobalContextUpdated(schemaContext);
 660     }
 661
 662     private void registerChangeListener(final RegisterChangeListener registerChangeListener) {
 663
 664         LOG.debug("{}: registerDataChangeListener for {}", persistenceId(), registerChangeListener.getPath());
 665
 666         ListenerRegistration<AsyncDataChangeListener<YangInstanceIdentifier,
 667                                                      NormalizedNode<?, ?>>> registration;
 668         if(isLeader()) {
 669             registration = doChangeListenerRegistration(registerChangeListener);
 670         } else {
 671             LOG.debug("{}: Shard is not the leader - delaying registration", persistenceId());
 672
 673             DelayedListenerRegistration delayedReg =
 674                     new DelayedListenerRegistration(registerChangeListener);
 675             delayedListenerRegistrations.add(delayedReg);
 676             registration = delayedReg;
 677         }
 678
 679         ActorRef listenerRegistration = getContext().actorOf(
 680                 DataChangeListenerRegistration.props(registration));
 681
 682         LOG.debug("{}: registerDataChangeListener sending reply, listenerRegistrationPath = {} ",
 683                 persistenceId(), listenerRegistration.path());
 684
 685         getSender().tell(new RegisterChangeListenerReply(listenerRegistration.path()), getSelf());
 686     }
 687
 688     private ListenerRegistration<AsyncDataChangeListener<YangInstanceIdentifier,
 689                                                NormalizedNode<?, ?>>> doChangeListenerRegistration(
 690             final RegisterChangeListener registerChangeListener) {
 691
 692         ActorSelection dataChangeListenerPath = getContext().system().actorSelection(
 693                 registerChangeListener.getDataChangeListenerPath());
 694
 695         // Notify the listener if notifications should be enabled or not
 696         // If this shard is the leader then it will enable notifications else
 697         // it will not
 698         dataChangeListenerPath.tell(new EnableNotification(true), getSelf());
 699
 700         // Now store a reference to the data change listener so it can be notified
 701         // at a later point if notifications should be enabled or disabled
 702         dataChangeListeners.add(dataChangeListenerPath);
 703
 704         AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>> listener =
 705                 new DataChangeListenerProxy(dataChangeListenerPath);
 706
 707         LOG.debug("{}: Registering for path {}", persistenceId(), registerChangeListener.getPath());
 708
 709         return store.registerChangeListener(registerChangeListener.getPath(), listener,
 710                 registerChangeListener.getScope());
 711     }
 712
 713     private boolean isMetricsCaptureEnabled(){
 714         CommonConfig config = new CommonConfig(getContext().system().settings().config());
 715         return config.isMetricCaptureEnabled();
 716     }
 717
 718     @Override
 719     protected
 720     void startLogRecoveryBatch(final int maxBatchSize) {
 721         currentLogRecoveryBatch = Lists.newArrayListWithCapacity(maxBatchSize);
 722
 723         if(LOG.isDebugEnabled()) {
 724             LOG.debug("{}: starting log recovery batch with max size {}", persistenceId(), maxBatchSize);
 725         }
 726     }
 727
 728     @Override
 729     protected void appendRecoveredLogEntry(final Payload data) {
 730         if(data instanceof ModificationPayload) {
 731             try {
 732                 currentLogRecoveryBatch.add(((ModificationPayload) data).getModification());
 733             } catch (ClassNotFoundException | IOException e) {
 734                 LOG.error("{}: Error extracting ModificationPayload", persistenceId(), e);
 735             }
 736         } else if (data instanceof CompositeModificationPayload) {
 737             currentLogRecoveryBatch.add(((CompositeModificationPayload) data).getModification());
 738         } else if (data instanceof CompositeModificationByteStringPayload) {
 739             currentLogRecoveryBatch.add(((CompositeModificationByteStringPayload) data).getModification());
 740         } else {
 741             LOG.error("{}: Unknown state received {} during recovery", persistenceId(), data);
 742         }
 743     }
 744
 745     @Override
 746     protected void applyRecoverySnapshot(final byte[] snapshotBytes) {
 747         if(recoveryCoordinator == null) {
 748             recoveryCoordinator = new ShardRecoveryCoordinator(persistenceId(), schemaContext,
 749                     LOG, name.toString());
 750         }
 751
 752         recoveryCoordinator.submit(snapshotBytes, store.newWriteOnlyTransaction());
 753
 754         if(LOG.isDebugEnabled()) {
 755             LOG.debug("{}: submitted recovery sbapshot", persistenceId());
 756         }
 757     }
 758
 759     @Override
 760     protected void applyCurrentLogRecoveryBatch() {
 761         if(recoveryCoordinator == null) {
 762             recoveryCoordinator = new ShardRecoveryCoordinator(persistenceId(), schemaContext,
 763                     LOG, name.toString());
 764         }
 765
 766         recoveryCoordinator.submit(currentLogRecoveryBatch, store.newWriteOnlyTransaction());
 767
 768         if(LOG.isDebugEnabled()) {
 769             LOG.debug("{}: submitted log recovery batch with size {}", persistenceId(),
 770                     currentLogRecoveryBatch.size());
 771         }
 772     }
 773
 774     @Override
 775     protected void onRecoveryComplete() {
 776         if(recoveryCoordinator != null) {
 777             Collection<DOMStoreWriteTransaction> txList = recoveryCoordinator.getTransactions();
 778
 779             if(LOG.isDebugEnabled()) {
 780                 LOG.debug("{}: recovery complete - committing {} Tx's", persistenceId(), txList.size());
 781             }
 782
 783             for(DOMStoreWriteTransaction tx: txList) {
 784                 try {
 785                     syncCommitTransaction(tx);
 786                     shardMBean.incrementCommittedTransactionCount();
 787                 } catch (InterruptedException | ExecutionException e) {
 788                     shardMBean.incrementFailedTransactionsCount();
 789                     LOG.error("{}: Failed to commit", persistenceId(), e);
 790                 }
 791             }
 792         }
 793
 794         recoveryCoordinator = null;
 795         currentLogRecoveryBatch = null;
 796
 797         //notify shard manager
 798         getContext().parent().tell(new ActorInitialized(), getSelf());
 799
 800         // Being paranoid here - this method should only be called once but just in case...
 801         if(txCommitTimeoutCheckSchedule == null) {
 802             // Schedule a message to be periodically sent to check if the current in-progress
 803             // transaction should be expired and aborted.
 804             FiniteDuration period = Duration.create(transactionCommitTimeout / 3, TimeUnit.MILLISECONDS);
 805             txCommitTimeoutCheckSchedule = getContext().system().scheduler().schedule(
 806                     period, period, getSelf(),
 807                     TX_COMMIT_TIMEOUT_CHECK_MESSAGE, getContext().dispatcher(), ActorRef.noSender());
 808         }
 809     }
 810
 811     @Override
 812     protected void applyState(final ActorRef clientActor, final String identifier, final Object data) {
 813
 814         if(data instanceof ModificationPayload) {
 815             try {
 816                 applyModificationToState(clientActor, identifier, ((ModificationPayload) data).getModification());
 817             } catch (ClassNotFoundException | IOException e) {
 818                 LOG.error("{}: Error extracting ModificationPayload", persistenceId(), e);
 819             }
 820         }
 821         else if (data instanceof CompositeModificationPayload) {
 822             Object modification = ((CompositeModificationPayload) data).getModification();
 823
 824             applyModificationToState(clientActor, identifier, modification);
 825         } else if(data instanceof CompositeModificationByteStringPayload ){
 826             Object modification = ((CompositeModificationByteStringPayload) data).getModification();
 827
 828             applyModificationToState(clientActor, identifier, modification);
 829         } else {
 830             LOG.error("{}: Unknown state received {} Class loader = {} CompositeNodeMod.ClassLoader = {}",
 831                     persistenceId(), data, data.getClass().getClassLoader(),
 832                     CompositeModificationPayload.class.getClassLoader());
 833         }
 834     }
 835
 836     private void applyModificationToState(ActorRef clientActor, String identifier, Object modification) {
 837         if(modification == null) {
 838             LOG.error(
 839                     "{}: modification is null - this is very unexpected, clientActor = {}, identifier = {}",
 840                     persistenceId(), identifier, clientActor != null ? clientActor.path().toString() : null);
 841         } else if(clientActor == null) {
 842             // There's no clientActor to which to send a commit reply so we must be applying
 843             // replicated state from the leader.
 844             commitWithNewTransaction(MutableCompositeModification.fromSerializable(modification));
 845         } else {
 846             // This must be the OK to commit after replication consensus.
 847             finishCommit(clientActor, identifier);
 848         }
 849     }
 850
 851     @Override
 852     protected void createSnapshot() {
 853         // Create a transaction actor. We are really going to treat the transaction as a worker
 854         // so that this actor does not get block building the snapshot. THe transaction actor will
 855         // after processing the CreateSnapshot message.
 856
 857         ActorRef createSnapshotTransaction = createTransaction(
 858                 TransactionProxy.TransactionType.READ_ONLY.ordinal(),
 859                 "createSnapshot" + ++createSnapshotTransactionCounter, "",
 860                 DataStoreVersions.CURRENT_VERSION);
 861
 862         createSnapshotTransaction.tell(CreateSnapshot.INSTANCE, self());
 863     }
 864
 865     @VisibleForTesting
 866     @Override
 867     protected void applySnapshot(final byte[] snapshotBytes) {
 868         // Since this will be done only on Recovery or when this actor is a Follower
 869         // we can safely commit everything in here. We not need to worry about event notifications
 870         // as they would have already been disabled on the follower
 871
 872         LOG.info("{}: Applying snapshot", persistenceId());
 873         try {
 874             DOMStoreWriteTransaction transaction = store.newWriteOnlyTransaction();
 875
 876             NormalizedNode<?, ?> node = SerializationUtils.deserializeNormalizedNode(snapshotBytes);
 877
 878             // delete everything first
 879             transaction.delete(DATASTORE_ROOT);
 880
 881             // Add everything from the remote node back
 882             transaction.write(DATASTORE_ROOT, node);
 883             syncCommitTransaction(transaction);
 884         } catch (InterruptedException | ExecutionException e) {
 885             LOG.error("{}: An exception occurred when applying snapshot", persistenceId(), e);
 886         } finally {
 887             LOG.info("{}: Done applying snapshot", persistenceId());
 888         }
 889     }
 890
 891     @Override
 892     protected void onStateChanged() {
 893         boolean isLeader = isLeader();
 894         for (ActorSelection dataChangeListener : dataChangeListeners) {
 895             dataChangeListener.tell(new EnableNotification(isLeader), getSelf());
 896         }
 897
 898         if(isLeader) {
 899             for(DelayedListenerRegistration reg: delayedListenerRegistrations) {
 900                 if(!reg.isClosed()) {
 901                     reg.setDelegate(doChangeListenerRegistration(reg.getRegisterChangeListener()));
 902                 }
 903             }
 904
 905             delayedListenerRegistrations.clear();
 906         }
 907
 908         // If this actor is no longer the leader close all the transaction chains
 909         if(!isLeader){
 910             for(Map.Entry<String, DOMStoreTransactionChain> entry : transactionChains.entrySet()){
 911                 if(LOG.isDebugEnabled()) {
 912                     LOG.debug(
 913                         "{}: onStateChanged: Closing transaction chain {} because shard {} is no longer the leader",
 914                         persistenceId(), entry.getKey(), getId());
 915                 }
 916                 entry.getValue().close();
 917             }
 918
 919             transactionChains.clear();
 920         }
 921     }
 922
 923     @Override
 924     protected DataPersistenceProvider persistence() {
 925         return dataPersistenceProvider;
 926     }
 927
 928     @Override public String persistenceId() {
 929         return this.name.toString();
 930     }
 931
 932     @VisibleForTesting
 933     DataPersistenceProvider getDataPersistenceProvider() {
 934         return dataPersistenceProvider;
 935     }
 936
 937     private static class ShardCreator implements Creator<Shard> {
 938
 939         private static final long serialVersionUID = 1L;
 940
 941         final ShardIdentifier name;
 942         final Map<ShardIdentifier, String> peerAddresses;
 943         final DatastoreContext datastoreContext;
 944         final SchemaContext schemaContext;
 945
 946         ShardCreator(final ShardIdentifier name, final Map<ShardIdentifier, String> peerAddresses,
 947                 final DatastoreContext datastoreContext, final SchemaContext schemaContext) {
 948             this.name = name;
 949             this.peerAddresses = peerAddresses;
 950             this.datastoreContext = datastoreContext;
 951             this.schemaContext = schemaContext;
 952         }
 953
 954         @Override
 955         public Shard create() throws Exception {
 956             return new Shard(name, peerAddresses, datastoreContext, schemaContext);
 957         }
 958     }
 959
 960     @VisibleForTesting
 961     public InMemoryDOMDataStore getDataStore() {
 962         return store;
 963     }
 964
 965     @VisibleForTesting
 966     ShardStats getShardMBean() {
 967         return shardMBean;
 968     }
 969
 970     private static class DelayedListenerRegistration implements
 971         ListenerRegistration<AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>>> {
 972
 973         private volatile boolean closed;
 974
 975         private final RegisterChangeListener registerChangeListener;
 976
 977         private volatile ListenerRegistration<AsyncDataChangeListener<YangInstanceIdentifier,
 978                                                              NormalizedNode<?, ?>>> delegate;
 979
 980         DelayedListenerRegistration(final RegisterChangeListener registerChangeListener) {
 981             this.registerChangeListener = registerChangeListener;
 982         }
 983
 984         void setDelegate( final ListenerRegistration<AsyncDataChangeListener<YangInstanceIdentifier,
 985                                             NormalizedNode<?, ?>>> registration) {
 986             this.delegate = registration;
 987         }
 988
 989         boolean isClosed() {
 990             return closed;
 991         }
 992
 993         RegisterChangeListener getRegisterChangeListener() {
 994             return registerChangeListener;
 995         }
 996
 997         @Override
 998         public AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>> getInstance() {
 999             return delegate != null ? delegate.getInstance() : null;
1000         }
1001
1002         @Override
1003         public void close() {
1004             closed = true;
1005             if(delegate != null) {
1006                 delegate.close();
1007             }
1008         }
1009     }
1010 }