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.RoleChangeNotifier;
  67 import org.opendaylight.controller.cluster.raft.RaftActor;
  68 import org.opendaylight.controller.cluster.raft.ReplicatedLogEntry;
  69 import org.opendaylight.controller.cluster.raft.messages.AppendEntriesReply;
  70 import org.opendaylight.controller.cluster.raft.protobuff.client.messages.CompositeModificationByteStringPayload;
  71 import org.opendaylight.controller.cluster.raft.protobuff.client.messages.CompositeModificationPayload;
  72 import org.opendaylight.controller.cluster.raft.protobuff.client.messages.Payload;
  73 import org.opendaylight.controller.md.sal.common.api.data.AsyncDataChangeListener;
  74 import org.opendaylight.controller.md.sal.dom.store.impl.InMemoryDOMDataStore;
  75 import org.opendaylight.controller.md.sal.dom.store.impl.InMemoryDOMDataStoreFactory;
  76 import org.opendaylight.controller.sal.core.spi.data.DOMStoreThreePhaseCommitCohort;
  77 import org.opendaylight.controller.sal.core.spi.data.DOMStoreTransaction;
  78 import org.opendaylight.controller.sal.core.spi.data.DOMStoreTransactionChain;
  79 import org.opendaylight.controller.sal.core.spi.data.DOMStoreTransactionFactory;
  80 import org.opendaylight.controller.sal.core.spi.data.DOMStoreWriteTransaction;
  81 import org.opendaylight.yangtools.concepts.ListenerRegistration;
  82 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  83 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  84 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  85 import scala.concurrent.duration.Duration;
  86 import scala.concurrent.duration.FiniteDuration;
  87
  88 /**
  89  * A Shard represents a portion of the logical data tree <br/>
  90  * <p>
  91  * Our Shard uses InMemoryDataStore as it's internal representation and delegates all requests it
  92  * </p>
  93  */
  94 public class Shard extends RaftActor {
  95
  96     private static final YangInstanceIdentifier DATASTORE_ROOT = YangInstanceIdentifier.builder().build();
  97
  98     private static final Object TX_COMMIT_TIMEOUT_CHECK_MESSAGE = "txCommitTimeoutCheck";
  99
 100     @VisibleForTesting
 101     static final String DEFAULT_NAME = "default";
 102
 103     // The state of this Shard
 104     private final InMemoryDOMDataStore store;
 105
 106     /// The name of this shard
 107     private final ShardIdentifier name;
 108
 109     private final ShardStats shardMBean;
 110
 111     private final List<ActorSelection> dataChangeListeners =  Lists.newArrayList();
 112
 113     private final List<DelayedListenerRegistration> delayedListenerRegistrations =
 114                                                                        Lists.newArrayList();
 115
 116     private DatastoreContext datastoreContext;
 117
 118     private DataPersistenceProvider dataPersistenceProvider;
 119
 120     private SchemaContext schemaContext;
 121
 122     private int createSnapshotTransactionCounter;
 123
 124     private final ShardCommitCoordinator commitCoordinator;
 125
 126     private long transactionCommitTimeout;
 127
 128     private Cancellable txCommitTimeoutCheckSchedule;
 129
 130     private final Optional<ActorRef> roleChangeNotifier;
 131
 132     private final MessageTracker appendEntriesReplyTracker;
 133
 134     /**
 135      * Coordinates persistence recovery on startup.
 136      */
 137     private ShardRecoveryCoordinator recoveryCoordinator;
 138     private List<Object> currentLogRecoveryBatch;
 139
 140     private final Map<String, DOMStoreTransactionChain> transactionChains = new HashMap<>();
 141
 142     private final String txnDispatcherPath;
 143
 144     protected Shard(final ShardIdentifier name, final Map<ShardIdentifier, String> peerAddresses,
 145             final DatastoreContext datastoreContext, final SchemaContext schemaContext) {
 146         super(name.toString(), mapPeerAddresses(peerAddresses),
 147                 Optional.of(datastoreContext.getShardRaftConfig()));
 148
 149         this.name = name;
 150         this.datastoreContext = datastoreContext;
 151         this.schemaContext = schemaContext;
 152         this.dataPersistenceProvider = (datastoreContext.isPersistent())
 153                 ? new PersistentDataProvider() : new NonPersistentRaftDataProvider();
 154         this.txnDispatcherPath = new Dispatchers(context().system().dispatchers())
 155                 .getDispatcherPath(Dispatchers.DispatcherType.Transaction);
 156
 157
 158         LOG.info("Shard created : {}, persistent : {}", name, datastoreContext.isPersistent());
 159
 160         store = InMemoryDOMDataStoreFactory.create(name.toString(), null,
 161                 datastoreContext.getDataStoreProperties());
 162
 163         if(schemaContext != null) {
 164             store.onGlobalContextUpdated(schemaContext);
 165         }
 166
 167         shardMBean = ShardMBeanFactory.getShardStatsMBean(name.toString(),
 168                 datastoreContext.getDataStoreMXBeanType());
 169         shardMBean.setNotificationManager(store.getDataChangeListenerNotificationManager());
 170
 171         if (isMetricsCaptureEnabled()) {
 172             getContext().become(new MeteringBehavior(this));
 173         }
 174
 175         commitCoordinator = new ShardCommitCoordinator(TimeUnit.SECONDS.convert(1, TimeUnit.MINUTES),
 176                 datastoreContext.getShardTransactionCommitQueueCapacity(), LOG, name.toString());
 177
 178         setTransactionCommitTimeout();
 179
 180         // create a notifier actor for each cluster member
 181         roleChangeNotifier = createRoleChangeNotifier(name.toString());
 182
 183         appendEntriesReplyTracker = new MessageTracker(AppendEntriesReply.class,
 184                 getRaftActorContext().getConfigParams().getIsolatedCheckIntervalInMillis());
 185     }
 186
 187     private void setTransactionCommitTimeout() {
 188         transactionCommitTimeout = TimeUnit.MILLISECONDS.convert(
 189                 datastoreContext.getShardTransactionCommitTimeoutInSeconds(), TimeUnit.SECONDS);
 190     }
 191
 192     private static Map<String, String> mapPeerAddresses(
 193         final Map<ShardIdentifier, String> peerAddresses) {
 194         Map<String, String> map = new HashMap<>();
 195
 196         for (Map.Entry<ShardIdentifier, String> entry : peerAddresses
 197             .entrySet()) {
 198             map.put(entry.getKey().toString(), entry.getValue());
 199         }
 200
 201         return map;
 202     }
 203
 204     public static Props props(final ShardIdentifier name,
 205         final Map<ShardIdentifier, String> peerAddresses,
 206         final DatastoreContext datastoreContext, final SchemaContext schemaContext) {
 207         Preconditions.checkNotNull(name, "name should not be null");
 208         Preconditions.checkNotNull(peerAddresses, "peerAddresses should not be null");
 209         Preconditions.checkNotNull(datastoreContext, "dataStoreContext should not be null");
 210         Preconditions.checkNotNull(schemaContext, "schemaContext should not be null");
 211
 212         return Props.create(new ShardCreator(name, peerAddresses, datastoreContext, schemaContext));
 213     }
 214
 215     private Optional<ActorRef> createRoleChangeNotifier(String shardId) {
 216         ActorRef shardRoleChangeNotifier = this.getContext().actorOf(
 217             RoleChangeNotifier.getProps(shardId), shardId + "-notifier");
 218         return Optional.<ActorRef>of(shardRoleChangeNotifier);
 219     }
 220
 221     @Override
 222     public void postStop() {
 223         LOG.info("Stopping Shard {}", persistenceId());
 224
 225         super.postStop();
 226
 227         if(txCommitTimeoutCheckSchedule != null) {
 228             txCommitTimeoutCheckSchedule.cancel();
 229         }
 230
 231         shardMBean.unregisterMBean();
 232     }
 233
 234     @Override
 235     public void onReceiveRecover(final Object message) throws Exception {
 236         if(LOG.isDebugEnabled()) {
 237             LOG.debug("{}: onReceiveRecover: Received message {} from {}", persistenceId(),
 238                 message.getClass().toString(), getSender());
 239         }
 240
 241         if (message instanceof RecoveryFailure){
 242             LOG.error("{}: Recovery failed because of this cause",
 243                     persistenceId(), ((RecoveryFailure) message).cause());
 244
 245             // Even though recovery failed, we still need to finish our recovery, eg send the
 246             // ActorInitialized message and start the txCommitTimeoutCheckSchedule.
 247             onRecoveryComplete();
 248         } else {
 249             super.onReceiveRecover(message);
 250             if(LOG.isTraceEnabled()) {
 251                 appendEntriesReplyTracker.begin();
 252             }
 253         }
 254     }
 255
 256     @Override
 257     public void onReceiveCommand(final Object message) throws Exception {
 258
 259         MessageTracker.Context context = appendEntriesReplyTracker.received(message);
 260
 261         if(context.error().isPresent()){
 262             LOG.trace("{} : AppendEntriesReply failed to arrive at the expected interval {}", persistenceId(),
 263                     context.error());
 264         }
 265
 266         try {
 267             if (message.getClass().equals(CreateTransaction.SERIALIZABLE_CLASS)) {
 268                 handleCreateTransaction(message);
 269             } else if (message instanceof ForwardedReadyTransaction) {
 270                 handleForwardedReadyTransaction((ForwardedReadyTransaction) message);
 271             } else if (message.getClass().equals(CanCommitTransaction.SERIALIZABLE_CLASS)) {
 272                 handleCanCommitTransaction(CanCommitTransaction.fromSerializable(message));
 273             } else if (message.getClass().equals(CommitTransaction.SERIALIZABLE_CLASS)) {
 274                 handleCommitTransaction(CommitTransaction.fromSerializable(message));
 275             } else if (message.getClass().equals(AbortTransaction.SERIALIZABLE_CLASS)) {
 276                 handleAbortTransaction(AbortTransaction.fromSerializable(message));
 277             } else if (message.getClass().equals(CloseTransactionChain.SERIALIZABLE_CLASS)) {
 278                 closeTransactionChain(CloseTransactionChain.fromSerializable(message));
 279             } else if (message instanceof RegisterChangeListener) {
 280                 registerChangeListener((RegisterChangeListener) message);
 281             } else if (message instanceof UpdateSchemaContext) {
 282                 updateSchemaContext((UpdateSchemaContext) message);
 283             } else if (message instanceof PeerAddressResolved) {
 284                 PeerAddressResolved resolved = (PeerAddressResolved) message;
 285                 setPeerAddress(resolved.getPeerId().toString(),
 286                         resolved.getPeerAddress());
 287             } else if (message.equals(TX_COMMIT_TIMEOUT_CHECK_MESSAGE)) {
 288                 handleTransactionCommitTimeoutCheck();
 289             } else if(message instanceof DatastoreContext) {
 290                 onDatastoreContext((DatastoreContext)message);
 291             } else {
 292                 super.onReceiveCommand(message);
 293             }
 294         } finally {
 295             context.done();
 296         }
 297     }
 298
 299     @Override
 300     protected Optional<ActorRef> getRoleChangeNotifier() {
 301         return roleChangeNotifier;
 302     }
 303
 304     private void onDatastoreContext(DatastoreContext context) {
 305         datastoreContext = context;
 306
 307         commitCoordinator.setQueueCapacity(datastoreContext.getShardTransactionCommitQueueCapacity());
 308
 309         setTransactionCommitTimeout();
 310
 311         if(datastoreContext.isPersistent() &&
 312                 dataPersistenceProvider instanceof NonPersistentRaftDataProvider) {
 313             dataPersistenceProvider = new PersistentDataProvider();
 314         } else if(!datastoreContext.isPersistent() &&
 315                 dataPersistenceProvider instanceof PersistentDataProvider) {
 316             dataPersistenceProvider = new NonPersistentRaftDataProvider();
 317         }
 318
 319         updateConfigParams(datastoreContext.getShardRaftConfig());
 320     }
 321
 322     private void handleTransactionCommitTimeoutCheck() {
 323         CohortEntry cohortEntry = commitCoordinator.getCurrentCohortEntry();
 324         if(cohortEntry != null) {
 325             long elapsed = System.currentTimeMillis() - cohortEntry.getLastAccessTime();
 326             if(elapsed > transactionCommitTimeout) {
 327                 LOG.warn("{}: Current transaction {} has timed out after {} ms - aborting",
 328                         persistenceId(), cohortEntry.getTransactionID(), transactionCommitTimeout);
 329
 330                 doAbortTransaction(cohortEntry.getTransactionID(), null);
 331             }
 332         }
 333     }
 334
 335     private void handleCommitTransaction(final CommitTransaction commit) {
 336         final String transactionID = commit.getTransactionID();
 337
 338         LOG.debug("{}: Committing transaction {}", persistenceId(), transactionID);
 339
 340         // Get the current in-progress cohort entry in the commitCoordinator if it corresponds to
 341         // this transaction.
 342         final CohortEntry cohortEntry = commitCoordinator.getCohortEntryIfCurrent(transactionID);
 343         if(cohortEntry == null) {
 344             // We're not the current Tx - the Tx was likely expired b/c it took too long in
 345             // between the canCommit and commit messages.
 346             IllegalStateException ex = new IllegalStateException(
 347                     String.format("%s: Cannot commit transaction %s - it is not the current transaction",
 348                             persistenceId(), transactionID));
 349             LOG.error(ex.getMessage());
 350             shardMBean.incrementFailedTransactionsCount();
 351             getSender().tell(new akka.actor.Status.Failure(ex), getSelf());
 352             return;
 353         }
 354
 355         // We perform the preCommit phase here atomically with the commit phase. This is an
 356         // optimization to eliminate the overhead of an extra preCommit message. We lose front-end
 357         // coordination of preCommit across shards in case of failure but preCommit should not
 358         // normally fail since we ensure only one concurrent 3-phase commit.
 359
 360         try {
 361             // We block on the future here so we don't have to worry about possibly accessing our
 362             // state on a different thread outside of our dispatcher. Also, the data store
 363             // currently uses a same thread executor anyway.
 364             cohortEntry.getCohort().preCommit().get();
 365
 366             // If we do not have any followers and we are not using persistence we can
 367             // apply modification to the state immediately
 368             if(!hasFollowers() && !persistence().isRecoveryApplicable()){
 369                 applyModificationToState(getSender(), transactionID, cohortEntry.getModification());
 370             } else {
 371                 Shard.this.persistData(getSender(), transactionID,
 372                         new ModificationPayload(cohortEntry.getModification()));
 373             }
 374         } catch (Exception e) {
 375             LOG.error("{} An exception occurred while preCommitting transaction {}",
 376                     persistenceId(), cohortEntry.getTransactionID(), e);
 377             shardMBean.incrementFailedTransactionsCount();
 378             getSender().tell(new akka.actor.Status.Failure(e), getSelf());
 379         }
 380
 381         cohortEntry.updateLastAccessTime();
 382     }
 383
 384     private void finishCommit(@Nonnull final ActorRef sender, final @Nonnull String transactionID) {
 385         // With persistence enabled, this method is called via applyState by the leader strategy
 386         // after the commit has been replicated to a majority of the followers.
 387
 388         CohortEntry cohortEntry = commitCoordinator.getCohortEntryIfCurrent(transactionID);
 389         if(cohortEntry == null) {
 390             // The transaction is no longer the current commit. This can happen if the transaction
 391             // was aborted prior, most likely due to timeout in the front-end. We need to finish
 392             // committing the transaction though since it was successfully persisted and replicated
 393             // however we can't use the original cohort b/c it was already preCommitted and may
 394             // conflict with the current commit or may have been aborted so we commit with a new
 395             // transaction.
 396             cohortEntry = commitCoordinator.getAndRemoveCohortEntry(transactionID);
 397             if(cohortEntry != null) {
 398                 commitWithNewTransaction(cohortEntry.getModification());
 399                 sender.tell(CommitTransactionReply.INSTANCE.toSerializable(), getSelf());
 400             } else {
 401                 // This really shouldn't happen - it likely means that persistence or replication
 402                 // took so long to complete such that the cohort entry was expired from the cache.
 403                 IllegalStateException ex = new IllegalStateException(
 404                         String.format("%s: Could not finish committing transaction %s - no CohortEntry found",
 405                                 persistenceId(), transactionID));
 406                 LOG.error(ex.getMessage());
 407                 sender.tell(new akka.actor.Status.Failure(ex), getSelf());
 408             }
 409
 410             return;
 411         }
 412
 413         LOG.debug("{}: Finishing commit for transaction {}", persistenceId(), cohortEntry.getTransactionID());
 414
 415         try {
 416             // We block on the future here so we don't have to worry about possibly accessing our
 417             // state on a different thread outside of our dispatcher. Also, the data store
 418             // currently uses a same thread executor anyway.
 419             cohortEntry.getCohort().commit().get();
 420
 421             sender.tell(CommitTransactionReply.INSTANCE.toSerializable(), getSelf());
 422
 423             shardMBean.incrementCommittedTransactionCount();
 424             shardMBean.setLastCommittedTransactionTime(System.currentTimeMillis());
 425
 426         } catch (Exception e) {
 427             sender.tell(new akka.actor.Status.Failure(e), getSelf());
 428
 429             LOG.error("{}, An exception occurred while committing transaction {}", persistenceId(),
 430                     transactionID, e);
 431             shardMBean.incrementFailedTransactionsCount();
 432         } finally {
 433             commitCoordinator.currentTransactionComplete(transactionID, true);
 434         }
 435     }
 436
 437     private void handleCanCommitTransaction(final CanCommitTransaction canCommit) {
 438         LOG.debug("{}: Can committing transaction {}", persistenceId(), canCommit.getTransactionID());
 439         commitCoordinator.handleCanCommit(canCommit, getSender(), self());
 440     }
 441
 442     private void handleForwardedReadyTransaction(ForwardedReadyTransaction ready) {
 443         LOG.debug("{}: Readying transaction {}, client version {}", persistenceId(),
 444                 ready.getTransactionID(), ready.getTxnClientVersion());
 445
 446         // This message is forwarded by the ShardTransaction on ready. We cache the cohort in the
 447         // commitCoordinator in preparation for the subsequent three phase commit initiated by
 448         // the front-end.
 449         commitCoordinator.transactionReady(ready.getTransactionID(), ready.getCohort(),
 450                 ready.getModification());
 451
 452         // Return our actor path as we'll handle the three phase commit, except if the Tx client
 453         // version < 1 (Helium-1 version). This means the Tx was initiated by a base Helium version
 454         // node. In that case, the subsequent 3-phase commit messages won't contain the
 455         // transactionId so to maintain backwards compatibility, we create a separate cohort actor
 456         // to provide the compatible behavior.
 457         ActorRef replyActorPath = self();
 458         if(ready.getTxnClientVersion() < DataStoreVersions.HELIUM_1_VERSION) {
 459             LOG.debug("{}: Creating BackwardsCompatibleThreePhaseCommitCohort", persistenceId());
 460             replyActorPath = getContext().actorOf(BackwardsCompatibleThreePhaseCommitCohort.props(
 461                     ready.getTransactionID()));
 462         }
 463
 464         ReadyTransactionReply readyTransactionReply = new ReadyTransactionReply(
 465                 Serialization.serializedActorPath(replyActorPath));
 466         getSender().tell(ready.isReturnSerialized() ? readyTransactionReply.toSerializable() :
 467                 readyTransactionReply, getSelf());
 468     }
 469
 470     private void handleAbortTransaction(final AbortTransaction abort) {
 471         doAbortTransaction(abort.getTransactionID(), getSender());
 472     }
 473
 474     void doAbortTransaction(final String transactionID, final ActorRef sender) {
 475         final CohortEntry cohortEntry = commitCoordinator.getCohortEntryIfCurrent(transactionID);
 476         if(cohortEntry != null) {
 477             LOG.debug("{}: Aborting transaction {}", persistenceId(), transactionID);
 478
 479             // We don't remove the cached cohort entry here (ie pass false) in case the Tx was
 480             // aborted during replication in which case we may still commit locally if replication
 481             // succeeds.
 482             commitCoordinator.currentTransactionComplete(transactionID, false);
 483
 484             final ListenableFuture<Void> future = cohortEntry.getCohort().abort();
 485             final ActorRef self = getSelf();
 486
 487             Futures.addCallback(future, new FutureCallback<Void>() {
 488                 @Override
 489                 public void onSuccess(final Void v) {
 490                     shardMBean.incrementAbortTransactionsCount();
 491
 492                     if(sender != null) {
 493                         sender.tell(AbortTransactionReply.INSTANCE.toSerializable(), self);
 494                     }
 495                 }
 496
 497                 @Override
 498                 public void onFailure(final Throwable t) {
 499                     LOG.error("{}: An exception happened during abort", persistenceId(), t);
 500
 501                     if(sender != null) {
 502                         sender.tell(new akka.actor.Status.Failure(t), self);
 503                     }
 504                 }
 505             });
 506         }
 507     }
 508
 509     private void handleCreateTransaction(final Object message) {
 510         if (isLeader()) {
 511             createTransaction(CreateTransaction.fromSerializable(message));
 512         } else if (getLeader() != null) {
 513             getLeader().forward(message, getContext());
 514         } else {
 515             getSender().tell(new akka.actor.Status.Failure(new NoShardLeaderException(String.format(
 516                 "Could not find leader for shard %s so transaction cannot be created. This typically happens" +
 517                 " when the system is coming up or recovering and a leader is being elected. Try again" +
 518                 " later.", persistenceId()))), getSelf());
 519         }
 520     }
 521
 522     private void closeTransactionChain(final CloseTransactionChain closeTransactionChain) {
 523         DOMStoreTransactionChain chain =
 524             transactionChains.remove(closeTransactionChain.getTransactionChainId());
 525
 526         if(chain != null) {
 527             chain.close();
 528         }
 529     }
 530
 531     private ActorRef createTypedTransactionActor(int transactionType,
 532             ShardTransactionIdentifier transactionId, String transactionChainId,
 533             short clientVersion ) {
 534
 535         DOMStoreTransactionFactory factory = store;
 536
 537         if(!transactionChainId.isEmpty()) {
 538             factory = transactionChains.get(transactionChainId);
 539             if(factory == null){
 540                 DOMStoreTransactionChain transactionChain = store.createTransactionChain();
 541                 transactionChains.put(transactionChainId, transactionChain);
 542                 factory = transactionChain;
 543             }
 544         }
 545
 546         if(this.schemaContext == null) {
 547             throw new IllegalStateException("SchemaContext is not set");
 548         }
 549
 550         if (transactionType == TransactionProxy.TransactionType.READ_ONLY.ordinal()) {
 551
 552             shardMBean.incrementReadOnlyTransactionCount();
 553
 554             return createShardTransaction(factory.newReadOnlyTransaction(), transactionId, clientVersion);
 555
 556         } else if (transactionType == TransactionProxy.TransactionType.READ_WRITE.ordinal()) {
 557
 558             shardMBean.incrementReadWriteTransactionCount();
 559
 560             return createShardTransaction(factory.newReadWriteTransaction(), transactionId, clientVersion);
 561
 562         } else if (transactionType == TransactionProxy.TransactionType.WRITE_ONLY.ordinal()) {
 563
 564             shardMBean.incrementWriteOnlyTransactionCount();
 565
 566             return createShardTransaction(factory.newWriteOnlyTransaction(), transactionId, clientVersion);
 567         } else {
 568             throw new IllegalArgumentException(
 569                 "Shard="+name + ":CreateTransaction message has unidentified transaction type="
 570                     + transactionType);
 571         }
 572     }
 573
 574     private ActorRef createShardTransaction(DOMStoreTransaction transaction, ShardTransactionIdentifier transactionId,
 575                                             short clientVersion){
 576         return getContext().actorOf(
 577                 ShardTransaction.props(transaction, getSelf(),
 578                         schemaContext, datastoreContext, shardMBean,
 579                         transactionId.getRemoteTransactionId(), clientVersion)
 580                         .withDispatcher(txnDispatcherPath),
 581                 transactionId.toString());
 582
 583     }
 584
 585     private void createTransaction(CreateTransaction createTransaction) {
 586         try {
 587             ActorRef transactionActor = createTransaction(createTransaction.getTransactionType(),
 588                 createTransaction.getTransactionId(), createTransaction.getTransactionChainId(),
 589                 createTransaction.getVersion());
 590
 591             getSender().tell(new CreateTransactionReply(Serialization.serializedActorPath(transactionActor),
 592                     createTransaction.getTransactionId()).toSerializable(), getSelf());
 593         } catch (Exception e) {
 594             getSender().tell(new akka.actor.Status.Failure(e), getSelf());
 595         }
 596     }
 597
 598     private ActorRef createTransaction(int transactionType, String remoteTransactionId,
 599             String transactionChainId, short clientVersion) {
 600
 601         ShardTransactionIdentifier transactionId =
 602             ShardTransactionIdentifier.builder()
 603                 .remoteTransactionId(remoteTransactionId)
 604                 .build();
 605
 606         if(LOG.isDebugEnabled()) {
 607             LOG.debug("{}: Creating transaction : {} ", persistenceId(), transactionId);
 608         }
 609
 610         ActorRef transactionActor = createTypedTransactionActor(transactionType, transactionId,
 611                 transactionChainId, clientVersion);
 612
 613         return transactionActor;
 614     }
 615
 616     private void syncCommitTransaction(final DOMStoreWriteTransaction transaction)
 617         throws ExecutionException, InterruptedException {
 618         DOMStoreThreePhaseCommitCohort commitCohort = transaction.ready();
 619         commitCohort.preCommit().get();
 620         commitCohort.commit().get();
 621     }
 622
 623     private void commitWithNewTransaction(final Modification modification) {
 624         DOMStoreWriteTransaction tx = store.newWriteOnlyTransaction();
 625         modification.apply(tx);
 626         try {
 627             syncCommitTransaction(tx);
 628             shardMBean.incrementCommittedTransactionCount();
 629             shardMBean.setLastCommittedTransactionTime(System.currentTimeMillis());
 630         } catch (InterruptedException | ExecutionException e) {
 631             shardMBean.incrementFailedTransactionsCount();
 632             LOG.error("{}: Failed to commit", persistenceId(), e);
 633         }
 634     }
 635
 636     private void updateSchemaContext(final UpdateSchemaContext message) {
 637         this.schemaContext = message.getSchemaContext();
 638         updateSchemaContext(message.getSchemaContext());
 639         store.onGlobalContextUpdated(message.getSchemaContext());
 640     }
 641
 642     @VisibleForTesting
 643     void updateSchemaContext(final SchemaContext schemaContext) {
 644         store.onGlobalContextUpdated(schemaContext);
 645     }
 646
 647     private void registerChangeListener(final RegisterChangeListener registerChangeListener) {
 648
 649         LOG.debug("{}: registerDataChangeListener for {}", persistenceId(), registerChangeListener.getPath());
 650
 651         ListenerRegistration<AsyncDataChangeListener<YangInstanceIdentifier,
 652                                                      NormalizedNode<?, ?>>> registration;
 653         if(isLeader()) {
 654             registration = doChangeListenerRegistration(registerChangeListener);
 655         } else {
 656             LOG.debug("{}: Shard is not the leader - delaying registration", persistenceId());
 657
 658             DelayedListenerRegistration delayedReg =
 659                     new DelayedListenerRegistration(registerChangeListener);
 660             delayedListenerRegistrations.add(delayedReg);
 661             registration = delayedReg;
 662         }
 663
 664         ActorRef listenerRegistration = getContext().actorOf(
 665                 DataChangeListenerRegistration.props(registration));
 666
 667         LOG.debug("{}: registerDataChangeListener sending reply, listenerRegistrationPath = {} ",
 668                 persistenceId(), listenerRegistration.path());
 669
 670         getSender().tell(new RegisterChangeListenerReply(listenerRegistration.path()), getSelf());
 671     }
 672
 673     private ListenerRegistration<AsyncDataChangeListener<YangInstanceIdentifier,
 674                                                NormalizedNode<?, ?>>> doChangeListenerRegistration(
 675             final RegisterChangeListener registerChangeListener) {
 676
 677         ActorSelection dataChangeListenerPath = getContext().system().actorSelection(
 678                 registerChangeListener.getDataChangeListenerPath());
 679
 680         // Notify the listener if notifications should be enabled or not
 681         // If this shard is the leader then it will enable notifications else
 682         // it will not
 683         dataChangeListenerPath.tell(new EnableNotification(true), getSelf());
 684
 685         // Now store a reference to the data change listener so it can be notified
 686         // at a later point if notifications should be enabled or disabled
 687         dataChangeListeners.add(dataChangeListenerPath);
 688
 689         AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>> listener =
 690                 new DataChangeListenerProxy(dataChangeListenerPath);
 691
 692         LOG.debug("{}: Registering for path {}", persistenceId(), registerChangeListener.getPath());
 693
 694         return store.registerChangeListener(registerChangeListener.getPath(), listener,
 695                 registerChangeListener.getScope());
 696     }
 697
 698     private boolean isMetricsCaptureEnabled(){
 699         CommonConfig config = new CommonConfig(getContext().system().settings().config());
 700         return config.isMetricCaptureEnabled();
 701     }
 702
 703     @Override
 704     protected
 705     void startLogRecoveryBatch(final int maxBatchSize) {
 706         currentLogRecoveryBatch = Lists.newArrayListWithCapacity(maxBatchSize);
 707
 708         if(LOG.isDebugEnabled()) {
 709             LOG.debug("{}: starting log recovery batch with max size {}", persistenceId(), maxBatchSize);
 710         }
 711     }
 712
 713     @Override
 714     protected void appendRecoveredLogEntry(final Payload data) {
 715         if(data instanceof ModificationPayload) {
 716             try {
 717                 currentLogRecoveryBatch.add(((ModificationPayload) data).getModification());
 718             } catch (ClassNotFoundException | IOException e) {
 719                 LOG.error("{}: Error extracting ModificationPayload", persistenceId(), e);
 720             }
 721         } else if (data instanceof CompositeModificationPayload) {
 722             currentLogRecoveryBatch.add(((CompositeModificationPayload) data).getModification());
 723         } else if (data instanceof CompositeModificationByteStringPayload) {
 724             currentLogRecoveryBatch.add(((CompositeModificationByteStringPayload) data).getModification());
 725         } else {
 726             LOG.error("{}: Unknown state received {} during recovery", persistenceId(), data);
 727         }
 728     }
 729
 730     @Override
 731     protected void applyRecoverySnapshot(final byte[] snapshotBytes) {
 732         if(recoveryCoordinator == null) {
 733             recoveryCoordinator = new ShardRecoveryCoordinator(persistenceId(), schemaContext,
 734                     LOG, name.toString());
 735         }
 736
 737         recoveryCoordinator.submit(snapshotBytes, store.newWriteOnlyTransaction());
 738
 739         if(LOG.isDebugEnabled()) {
 740             LOG.debug("{}: submitted recovery sbapshot", persistenceId());
 741         }
 742     }
 743
 744     @Override
 745     protected void applyCurrentLogRecoveryBatch() {
 746         if(recoveryCoordinator == null) {
 747             recoveryCoordinator = new ShardRecoveryCoordinator(persistenceId(), schemaContext,
 748                     LOG, name.toString());
 749         }
 750
 751         recoveryCoordinator.submit(currentLogRecoveryBatch, store.newWriteOnlyTransaction());
 752
 753         if(LOG.isDebugEnabled()) {
 754             LOG.debug("{}: submitted log recovery batch with size {}", persistenceId(),
 755                     currentLogRecoveryBatch.size());
 756         }
 757     }
 758
 759     @Override
 760     protected void onRecoveryComplete() {
 761         if(recoveryCoordinator != null) {
 762             Collection<DOMStoreWriteTransaction> txList = recoveryCoordinator.getTransactions();
 763
 764             if(LOG.isDebugEnabled()) {
 765                 LOG.debug("{}: recovery complete - committing {} Tx's", persistenceId(), txList.size());
 766             }
 767
 768             for(DOMStoreWriteTransaction tx: txList) {
 769                 try {
 770                     syncCommitTransaction(tx);
 771                     shardMBean.incrementCommittedTransactionCount();
 772                 } catch (InterruptedException | ExecutionException e) {
 773                     shardMBean.incrementFailedTransactionsCount();
 774                     LOG.error("{}: Failed to commit", persistenceId(), e);
 775                 }
 776             }
 777         }
 778
 779         recoveryCoordinator = null;
 780         currentLogRecoveryBatch = null;
 781         updateJournalStats();
 782
 783         //notify shard manager
 784         getContext().parent().tell(new ActorInitialized(), getSelf());
 785
 786         // Being paranoid here - this method should only be called once but just in case...
 787         if(txCommitTimeoutCheckSchedule == null) {
 788             // Schedule a message to be periodically sent to check if the current in-progress
 789             // transaction should be expired and aborted.
 790             FiniteDuration period = Duration.create(transactionCommitTimeout / 3, TimeUnit.MILLISECONDS);
 791             txCommitTimeoutCheckSchedule = getContext().system().scheduler().schedule(
 792                     period, period, getSelf(),
 793                     TX_COMMIT_TIMEOUT_CHECK_MESSAGE, getContext().dispatcher(), ActorRef.noSender());
 794         }
 795     }
 796
 797     @Override
 798     protected void applyState(final ActorRef clientActor, final String identifier, final Object data) {
 799
 800         if(data instanceof ModificationPayload) {
 801             try {
 802                 applyModificationToState(clientActor, identifier, ((ModificationPayload) data).getModification());
 803             } catch (ClassNotFoundException | IOException e) {
 804                 LOG.error("{}: Error extracting ModificationPayload", persistenceId(), e);
 805             }
 806         }
 807         else if (data instanceof CompositeModificationPayload) {
 808             Object modification = ((CompositeModificationPayload) data).getModification();
 809
 810             applyModificationToState(clientActor, identifier, modification);
 811         } else if(data instanceof CompositeModificationByteStringPayload ){
 812             Object modification = ((CompositeModificationByteStringPayload) data).getModification();
 813
 814             applyModificationToState(clientActor, identifier, modification);
 815         } else {
 816             LOG.error("{}: Unknown state received {} Class loader = {} CompositeNodeMod.ClassLoader = {}",
 817                     persistenceId(), data, data.getClass().getClassLoader(),
 818                     CompositeModificationPayload.class.getClassLoader());
 819         }
 820
 821         updateJournalStats();
 822
 823     }
 824
 825     private void applyModificationToState(ActorRef clientActor, String identifier, Object modification) {
 826         if(modification == null) {
 827             LOG.error(
 828                     "{}: modification is null - this is very unexpected, clientActor = {}, identifier = {}",
 829                     persistenceId(), identifier, clientActor != null ? clientActor.path().toString() : null);
 830         } else if(clientActor == null) {
 831             // There's no clientActor to which to send a commit reply so we must be applying
 832             // replicated state from the leader.
 833             commitWithNewTransaction(MutableCompositeModification.fromSerializable(modification));
 834         } else {
 835             // This must be the OK to commit after replication consensus.
 836             finishCommit(clientActor, identifier);
 837         }
 838     }
 839
 840     private void updateJournalStats() {
 841         ReplicatedLogEntry lastLogEntry = getLastLogEntry();
 842
 843         if (lastLogEntry != null) {
 844             shardMBean.setLastLogIndex(lastLogEntry.getIndex());
 845             shardMBean.setLastLogTerm(lastLogEntry.getTerm());
 846         }
 847
 848         shardMBean.setCommitIndex(getCommitIndex());
 849         shardMBean.setLastApplied(getLastApplied());
 850         shardMBean.setInMemoryJournalDataSize(getRaftActorContext().getReplicatedLog().dataSize());
 851     }
 852
 853     @Override
 854     protected void createSnapshot() {
 855         // Create a transaction actor. We are really going to treat the transaction as a worker
 856         // so that this actor does not get block building the snapshot. THe transaction actor will
 857         // after processing the CreateSnapshot message.
 858
 859         ActorRef createSnapshotTransaction = createTransaction(
 860                 TransactionProxy.TransactionType.READ_ONLY.ordinal(),
 861                 "createSnapshot" + ++createSnapshotTransactionCounter, "",
 862                 DataStoreVersions.CURRENT_VERSION);
 863
 864         createSnapshotTransaction.tell(CreateSnapshot.INSTANCE, self());
 865     }
 866
 867     @VisibleForTesting
 868     @Override
 869     protected void applySnapshot(final byte[] snapshotBytes) {
 870         // Since this will be done only on Recovery or when this actor is a Follower
 871         // we can safely commit everything in here. We not need to worry about event notifications
 872         // as they would have already been disabled on the follower
 873
 874         LOG.info("{}: Applying snapshot", persistenceId());
 875         try {
 876             DOMStoreWriteTransaction transaction = store.newWriteOnlyTransaction();
 877
 878             NormalizedNode<?, ?> node = SerializationUtils.deserializeNormalizedNode(snapshotBytes);
 879
 880             // delete everything first
 881             transaction.delete(DATASTORE_ROOT);
 882
 883             // Add everything from the remote node back
 884             transaction.write(DATASTORE_ROOT, node);
 885             syncCommitTransaction(transaction);
 886         } catch (InterruptedException | ExecutionException e) {
 887             LOG.error("{}: An exception occurred when applying snapshot", persistenceId(), e);
 888         } finally {
 889             LOG.info("{}: Done applying snapshot", persistenceId());
 890         }
 891     }
 892
 893     @Override
 894     protected void onStateChanged() {
 895         boolean isLeader = isLeader();
 896         for (ActorSelection dataChangeListener : dataChangeListeners) {
 897             dataChangeListener.tell(new EnableNotification(isLeader), getSelf());
 898         }
 899
 900         if(isLeader) {
 901             for(DelayedListenerRegistration reg: delayedListenerRegistrations) {
 902                 if(!reg.isClosed()) {
 903                     reg.setDelegate(doChangeListenerRegistration(reg.getRegisterChangeListener()));
 904                 }
 905             }
 906
 907             delayedListenerRegistrations.clear();
 908         }
 909
 910         shardMBean.setRaftState(getRaftState().name());
 911         shardMBean.setCurrentTerm(getCurrentTerm());
 912
 913         // If this actor is no longer the leader close all the transaction chains
 914         if(!isLeader){
 915             for(Map.Entry<String, DOMStoreTransactionChain> entry : transactionChains.entrySet()){
 916                 if(LOG.isDebugEnabled()) {
 917                     LOG.debug(
 918                         "{}: onStateChanged: Closing transaction chain {} because shard {} is no longer the leader",
 919                         persistenceId(), entry.getKey(), getId());
 920                 }
 921                 entry.getValue().close();
 922             }
 923
 924             transactionChains.clear();
 925         }
 926     }
 927
 928     @Override
 929     protected DataPersistenceProvider persistence() {
 930         return dataPersistenceProvider;
 931     }
 932
 933     @Override protected void onLeaderChanged(final String oldLeader, final String newLeader) {
 934         shardMBean.setLeader(newLeader);
 935     }
 936
 937     @Override public String persistenceId() {
 938         return this.name.toString();
 939     }
 940
 941     @VisibleForTesting
 942     DataPersistenceProvider getDataPersistenceProvider() {
 943         return dataPersistenceProvider;
 944     }
 945
 946     private static class ShardCreator implements Creator<Shard> {
 947
 948         private static final long serialVersionUID = 1L;
 949
 950         final ShardIdentifier name;
 951         final Map<ShardIdentifier, String> peerAddresses;
 952         final DatastoreContext datastoreContext;
 953         final SchemaContext schemaContext;
 954
 955         ShardCreator(final ShardIdentifier name, final Map<ShardIdentifier, String> peerAddresses,
 956                 final DatastoreContext datastoreContext, final SchemaContext schemaContext) {
 957             this.name = name;
 958             this.peerAddresses = peerAddresses;
 959             this.datastoreContext = datastoreContext;
 960             this.schemaContext = schemaContext;
 961         }
 962
 963         @Override
 964         public Shard create() throws Exception {
 965             return new Shard(name, peerAddresses, datastoreContext, schemaContext);
 966         }
 967     }
 968
 969     @VisibleForTesting
 970     InMemoryDOMDataStore getDataStore() {
 971         return store;
 972     }
 973
 974     @VisibleForTesting
 975     ShardStats getShardMBean() {
 976         return shardMBean;
 977     }
 978
 979     private static class DelayedListenerRegistration implements
 980         ListenerRegistration<AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>>> {
 981
 982         private volatile boolean closed;
 983
 984         private final RegisterChangeListener registerChangeListener;
 985
 986         private volatile ListenerRegistration<AsyncDataChangeListener<YangInstanceIdentifier,
 987                                                              NormalizedNode<?, ?>>> delegate;
 988
 989         DelayedListenerRegistration(final RegisterChangeListener registerChangeListener) {
 990             this.registerChangeListener = registerChangeListener;
 991         }
 992
 993         void setDelegate( final ListenerRegistration<AsyncDataChangeListener<YangInstanceIdentifier,
 994                                             NormalizedNode<?, ?>>> registration) {
 995             this.delegate = registration;
 996         }
 997
 998         boolean isClosed() {
 999             return closed;
1000         }
1001
1002         RegisterChangeListener getRegisterChangeListener() {
1003             return registerChangeListener;
1004         }
1005
1006         @Override
1007         public AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>> getInstance() {
1008             return delegate != null ? delegate.getInstance() : null;
1009         }
1010
1011         @Override
1012         public void close() {
1013             closed = true;
1014             if(delegate != null) {
1015                 delegate.close();
1016             }
1017         }
1018     }
1019 }