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.ReplicatedLogEntry;
  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     /**
 136      * Coordinates persistence recovery on startup.
 137      */
 138     private ShardRecoveryCoordinator recoveryCoordinator;
 139     private List<Object> currentLogRecoveryBatch;
 140
 141     private final Map<String, DOMStoreTransactionChain> transactionChains = new HashMap<>();
 142
 143     private final String txnDispatcherPath;
 144
 145     protected Shard(final ShardIdentifier name, final Map<ShardIdentifier, String> peerAddresses,
 146             final DatastoreContext datastoreContext, final SchemaContext schemaContext) {
 147         super(name.toString(), mapPeerAddresses(peerAddresses),
 148                 Optional.of(datastoreContext.getShardRaftConfig()));
 149
 150         this.name = name;
 151         this.datastoreContext = datastoreContext;
 152         this.schemaContext = schemaContext;
 153         this.dataPersistenceProvider = (datastoreContext.isPersistent())
 154                 ? new PersistentDataProvider() : new NonPersistentRaftDataProvider();
 155         this.txnDispatcherPath = new Dispatchers(context().system().dispatchers())
 156                 .getDispatcherPath(Dispatchers.DispatcherType.Transaction);
 157
 158
 159         LOG.info("Shard created : {}, persistent : {}", name, datastoreContext.isPersistent());
 160
 161         store = InMemoryDOMDataStoreFactory.create(name.toString(), null,
 162                 datastoreContext.getDataStoreProperties());
 163
 164         if(schemaContext != null) {
 165             store.onGlobalContextUpdated(schemaContext);
 166         }
 167
 168         shardMBean = ShardMBeanFactory.getShardStatsMBean(name.toString(),
 169                 datastoreContext.getDataStoreMXBeanType());
 170         shardMBean.setNotificationManager(store.getDataChangeListenerNotificationManager());
 171
 172         if (isMetricsCaptureEnabled()) {
 173             getContext().become(new MeteringBehavior(this));
 174         }
 175
 176         commitCoordinator = new ShardCommitCoordinator(TimeUnit.SECONDS.convert(1, TimeUnit.MINUTES),
 177                 datastoreContext.getShardTransactionCommitQueueCapacity(), LOG, name.toString());
 178
 179         setTransactionCommitTimeout();
 180
 181         // create a notifier actor for each cluster member
 182         roleChangeNotifier = createRoleChangeNotifier(name.toString());
 183
 184         appendEntriesReplyTracker = new MessageTracker(AppendEntriesReply.class,
 185                 getRaftActorContext().getConfigParams().getIsolatedCheckIntervalInMillis());
 186     }
 187
 188     private void setTransactionCommitTimeout() {
 189         transactionCommitTimeout = TimeUnit.MILLISECONDS.convert(
 190                 datastoreContext.getShardTransactionCommitTimeoutInSeconds(), TimeUnit.SECONDS);
 191     }
 192
 193     private static Map<String, String> mapPeerAddresses(
 194         final Map<ShardIdentifier, String> peerAddresses) {
 195         Map<String, String> map = new HashMap<>();
 196
 197         for (Map.Entry<ShardIdentifier, String> entry : peerAddresses
 198             .entrySet()) {
 199             map.put(entry.getKey().toString(), entry.getValue());
 200         }
 201
 202         return map;
 203     }
 204
 205     public static Props props(final ShardIdentifier name,
 206         final Map<ShardIdentifier, String> peerAddresses,
 207         final DatastoreContext datastoreContext, final SchemaContext schemaContext) {
 208         Preconditions.checkNotNull(name, "name should not be null");
 209         Preconditions.checkNotNull(peerAddresses, "peerAddresses should not be null");
 210         Preconditions.checkNotNull(datastoreContext, "dataStoreContext should not be null");
 211         Preconditions.checkNotNull(schemaContext, "schemaContext should not be null");
 212
 213         return Props.create(new ShardCreator(name, peerAddresses, datastoreContext, schemaContext));
 214     }
 215
 216     private Optional<ActorRef> createRoleChangeNotifier(String shardId) {
 217         ActorRef shardRoleChangeNotifier = this.getContext().actorOf(
 218             RoleChangeNotifier.getProps(shardId), shardId + "-notifier");
 219         return Optional.of(shardRoleChangeNotifier);
 220     }
 221
 222     @Override
 223     public void postStop() {
 224         LOG.info("Stopping Shard {}", persistenceId());
 225
 226         super.postStop();
 227
 228         if(txCommitTimeoutCheckSchedule != null) {
 229             txCommitTimeoutCheckSchedule.cancel();
 230         }
 231
 232         shardMBean.unregisterMBean();
 233     }
 234
 235     @Override
 236     public void onReceiveRecover(final Object message) throws Exception {
 237         if(LOG.isDebugEnabled()) {
 238             LOG.debug("{}: onReceiveRecover: Received message {} from {}", persistenceId(),
 239                 message.getClass().toString(), getSender());
 240         }
 241
 242         if (message instanceof RecoveryFailure){
 243             LOG.error("{}: Recovery failed because of this cause",
 244                     persistenceId(), ((RecoveryFailure) message).cause());
 245
 246             // Even though recovery failed, we still need to finish our recovery, eg send the
 247             // ActorInitialized message and start the txCommitTimeoutCheckSchedule.
 248             onRecoveryComplete();
 249         } else {
 250             super.onReceiveRecover(message);
 251             if(LOG.isTraceEnabled()) {
 252                 appendEntriesReplyTracker.begin();
 253             }
 254         }
 255     }
 256
 257     @Override
 258     public void onReceiveCommand(final Object message) throws Exception {
 259
 260         MessageTracker.Context context = appendEntriesReplyTracker.received(message);
 261
 262         if(context.error().isPresent()){
 263             LOG.trace("{} : AppendEntriesReply failed to arrive at the expected interval {}", persistenceId(),
 264                     context.error());
 265         }
 266
 267         try {
 268             if (message.getClass().equals(CreateTransaction.SERIALIZABLE_CLASS)) {
 269                 handleCreateTransaction(message);
 270             } else if (message instanceof ForwardedReadyTransaction) {
 271                 handleForwardedReadyTransaction((ForwardedReadyTransaction) message);
 272             } else if (message.getClass().equals(CanCommitTransaction.SERIALIZABLE_CLASS)) {
 273                 handleCanCommitTransaction(CanCommitTransaction.fromSerializable(message));
 274             } else if (message.getClass().equals(CommitTransaction.SERIALIZABLE_CLASS)) {
 275                 handleCommitTransaction(CommitTransaction.fromSerializable(message));
 276             } else if (message.getClass().equals(AbortTransaction.SERIALIZABLE_CLASS)) {
 277                 handleAbortTransaction(AbortTransaction.fromSerializable(message));
 278             } else if (message.getClass().equals(CloseTransactionChain.SERIALIZABLE_CLASS)) {
 279                 closeTransactionChain(CloseTransactionChain.fromSerializable(message));
 280             } else if (message instanceof RegisterChangeListener) {
 281                 registerChangeListener((RegisterChangeListener) message);
 282             } else if (message instanceof UpdateSchemaContext) {
 283                 updateSchemaContext((UpdateSchemaContext) message);
 284             } else if (message instanceof PeerAddressResolved) {
 285                 PeerAddressResolved resolved = (PeerAddressResolved) message;
 286                 setPeerAddress(resolved.getPeerId().toString(),
 287                         resolved.getPeerAddress());
 288             } else if (message.equals(TX_COMMIT_TIMEOUT_CHECK_MESSAGE)) {
 289                 handleTransactionCommitTimeoutCheck();
 290             } else if(message instanceof DatastoreContext) {
 291                 onDatastoreContext((DatastoreContext)message);
 292             } else if(message instanceof RegisterRoleChangeListener){
 293                 roleChangeNotifier.get().forward(message, context());
 294             } else {
 295                 super.onReceiveCommand(message);
 296             }
 297         } finally {
 298             context.done();
 299         }
 300     }
 301
 302     @Override
 303     protected Optional<ActorRef> getRoleChangeNotifier() {
 304         return roleChangeNotifier;
 305     }
 306
 307     private void onDatastoreContext(DatastoreContext context) {
 308         datastoreContext = context;
 309
 310         commitCoordinator.setQueueCapacity(datastoreContext.getShardTransactionCommitQueueCapacity());
 311
 312         setTransactionCommitTimeout();
 313
 314         if(datastoreContext.isPersistent() &&
 315                 dataPersistenceProvider instanceof NonPersistentRaftDataProvider) {
 316             dataPersistenceProvider = new PersistentDataProvider();
 317         } else if(!datastoreContext.isPersistent() &&
 318                 dataPersistenceProvider instanceof PersistentDataProvider) {
 319             dataPersistenceProvider = new NonPersistentRaftDataProvider();
 320         }
 321
 322         updateConfigParams(datastoreContext.getShardRaftConfig());
 323     }
 324
 325     private void handleTransactionCommitTimeoutCheck() {
 326         CohortEntry cohortEntry = commitCoordinator.getCurrentCohortEntry();
 327         if(cohortEntry != null) {
 328             long elapsed = System.currentTimeMillis() - cohortEntry.getLastAccessTime();
 329             if(elapsed > transactionCommitTimeout) {
 330                 LOG.warn("{}: Current transaction {} has timed out after {} ms - aborting",
 331                         persistenceId(), cohortEntry.getTransactionID(), transactionCommitTimeout);
 332
 333                 doAbortTransaction(cohortEntry.getTransactionID(), null);
 334             }
 335         }
 336     }
 337
 338     private void handleCommitTransaction(final CommitTransaction commit) {
 339         final String transactionID = commit.getTransactionID();
 340
 341         LOG.debug("{}: Committing transaction {}", persistenceId(), transactionID);
 342
 343         // Get the current in-progress cohort entry in the commitCoordinator if it corresponds to
 344         // this transaction.
 345         final CohortEntry cohortEntry = commitCoordinator.getCohortEntryIfCurrent(transactionID);
 346         if(cohortEntry == null) {
 347             // We're not the current Tx - the Tx was likely expired b/c it took too long in
 348             // between the canCommit and commit messages.
 349             IllegalStateException ex = new IllegalStateException(
 350                     String.format("%s: Cannot commit transaction %s - it is not the current transaction",
 351                             persistenceId(), transactionID));
 352             LOG.error(ex.getMessage());
 353             shardMBean.incrementFailedTransactionsCount();
 354             getSender().tell(new akka.actor.Status.Failure(ex), getSelf());
 355             return;
 356         }
 357
 358         // We perform the preCommit phase here atomically with the commit phase. This is an
 359         // optimization to eliminate the overhead of an extra preCommit message. We lose front-end
 360         // coordination of preCommit across shards in case of failure but preCommit should not
 361         // normally fail since we ensure only one concurrent 3-phase commit.
 362
 363         try {
 364             // We block on the future here so we don't have to worry about possibly accessing our
 365             // state on a different thread outside of our dispatcher. Also, the data store
 366             // currently uses a same thread executor anyway.
 367             cohortEntry.getCohort().preCommit().get();
 368
 369             // If we do not have any followers and we are not using persistence we can
 370             // apply modification to the state immediately
 371             if(!hasFollowers() && !persistence().isRecoveryApplicable()){
 372                 applyModificationToState(getSender(), transactionID, cohortEntry.getModification());
 373             } else {
 374                 Shard.this.persistData(getSender(), transactionID,
 375                         new ModificationPayload(cohortEntry.getModification()));
 376             }
 377         } catch (Exception e) {
 378             LOG.error("{} An exception occurred while preCommitting transaction {}",
 379                     persistenceId(), cohortEntry.getTransactionID(), e);
 380             shardMBean.incrementFailedTransactionsCount();
 381             getSender().tell(new akka.actor.Status.Failure(e), getSelf());
 382         }
 383
 384         cohortEntry.updateLastAccessTime();
 385     }
 386
 387     private void finishCommit(@Nonnull final ActorRef sender, final @Nonnull String transactionID) {
 388         // With persistence enabled, this method is called via applyState by the leader strategy
 389         // after the commit has been replicated to a majority of the followers.
 390
 391         CohortEntry cohortEntry = commitCoordinator.getCohortEntryIfCurrent(transactionID);
 392         if(cohortEntry == null) {
 393             // The transaction is no longer the current commit. This can happen if the transaction
 394             // was aborted prior, most likely due to timeout in the front-end. We need to finish
 395             // committing the transaction though since it was successfully persisted and replicated
 396             // however we can't use the original cohort b/c it was already preCommitted and may
 397             // conflict with the current commit or may have been aborted so we commit with a new
 398             // transaction.
 399             cohortEntry = commitCoordinator.getAndRemoveCohortEntry(transactionID);
 400             if(cohortEntry != null) {
 401                 commitWithNewTransaction(cohortEntry.getModification());
 402                 sender.tell(CommitTransactionReply.INSTANCE.toSerializable(), getSelf());
 403             } else {
 404                 // This really shouldn't happen - it likely means that persistence or replication
 405                 // took so long to complete such that the cohort entry was expired from the cache.
 406                 IllegalStateException ex = new IllegalStateException(
 407                         String.format("%s: Could not finish committing transaction %s - no CohortEntry found",
 408                                 persistenceId(), transactionID));
 409                 LOG.error(ex.getMessage());
 410                 sender.tell(new akka.actor.Status.Failure(ex), getSelf());
 411             }
 412
 413             return;
 414         }
 415
 416         LOG.debug("{}: Finishing commit for transaction {}", persistenceId(), cohortEntry.getTransactionID());
 417
 418         try {
 419             // We block on the future here so we don't have to worry about possibly accessing our
 420             // state on a different thread outside of our dispatcher. Also, the data store
 421             // currently uses a same thread executor anyway.
 422             cohortEntry.getCohort().commit().get();
 423
 424             sender.tell(CommitTransactionReply.INSTANCE.toSerializable(), getSelf());
 425
 426             shardMBean.incrementCommittedTransactionCount();
 427             shardMBean.setLastCommittedTransactionTime(System.currentTimeMillis());
 428
 429         } catch (Exception e) {
 430             sender.tell(new akka.actor.Status.Failure(e), getSelf());
 431
 432             LOG.error("{}, An exception occurred while committing transaction {}", persistenceId(),
 433                     transactionID, e);
 434             shardMBean.incrementFailedTransactionsCount();
 435         } finally {
 436             commitCoordinator.currentTransactionComplete(transactionID, true);
 437         }
 438     }
 439
 440     private void handleCanCommitTransaction(final CanCommitTransaction canCommit) {
 441         LOG.debug("{}: Can committing transaction {}", persistenceId(), canCommit.getTransactionID());
 442         commitCoordinator.handleCanCommit(canCommit, getSender(), self());
 443     }
 444
 445     private void handleForwardedReadyTransaction(ForwardedReadyTransaction ready) {
 446         LOG.debug("{}: Readying transaction {}, client version {}", persistenceId(),
 447                 ready.getTransactionID(), ready.getTxnClientVersion());
 448
 449         // This message is forwarded by the ShardTransaction on ready. We cache the cohort in the
 450         // commitCoordinator in preparation for the subsequent three phase commit initiated by
 451         // the front-end.
 452         commitCoordinator.transactionReady(ready.getTransactionID(), ready.getCohort(),
 453                 ready.getModification());
 454
 455         // Return our actor path as we'll handle the three phase commit, except if the Tx client
 456         // version < 1 (Helium-1 version). This means the Tx was initiated by a base Helium version
 457         // node. In that case, the subsequent 3-phase commit messages won't contain the
 458         // transactionId so to maintain backwards compatibility, we create a separate cohort actor
 459         // to provide the compatible behavior.
 460         ActorRef replyActorPath = self();
 461         if(ready.getTxnClientVersion() < DataStoreVersions.HELIUM_1_VERSION) {
 462             LOG.debug("{}: Creating BackwardsCompatibleThreePhaseCommitCohort", persistenceId());
 463             replyActorPath = getContext().actorOf(BackwardsCompatibleThreePhaseCommitCohort.props(
 464                     ready.getTransactionID()));
 465         }
 466
 467         ReadyTransactionReply readyTransactionReply = new ReadyTransactionReply(
 468                 Serialization.serializedActorPath(replyActorPath));
 469         getSender().tell(ready.isReturnSerialized() ? readyTransactionReply.toSerializable() :
 470                 readyTransactionReply, getSelf());
 471     }
 472
 473     private void handleAbortTransaction(final AbortTransaction abort) {
 474         doAbortTransaction(abort.getTransactionID(), getSender());
 475     }
 476
 477     void doAbortTransaction(final String transactionID, final ActorRef sender) {
 478         final CohortEntry cohortEntry = commitCoordinator.getCohortEntryIfCurrent(transactionID);
 479         if(cohortEntry != null) {
 480             LOG.debug("{}: Aborting transaction {}", persistenceId(), transactionID);
 481
 482             // We don't remove the cached cohort entry here (ie pass false) in case the Tx was
 483             // aborted during replication in which case we may still commit locally if replication
 484             // succeeds.
 485             commitCoordinator.currentTransactionComplete(transactionID, false);
 486
 487             final ListenableFuture<Void> future = cohortEntry.getCohort().abort();
 488             final ActorRef self = getSelf();
 489
 490             Futures.addCallback(future, new FutureCallback<Void>() {
 491                 @Override
 492                 public void onSuccess(final Void v) {
 493                     shardMBean.incrementAbortTransactionsCount();
 494
 495                     if(sender != null) {
 496                         sender.tell(AbortTransactionReply.INSTANCE.toSerializable(), self);
 497                     }
 498                 }
 499
 500                 @Override
 501                 public void onFailure(final Throwable t) {
 502                     LOG.error("{}: An exception happened during abort", persistenceId(), t);
 503
 504                     if(sender != null) {
 505                         sender.tell(new akka.actor.Status.Failure(t), self);
 506                     }
 507                 }
 508             });
 509         }
 510     }
 511
 512     private void handleCreateTransaction(final Object message) {
 513         if (isLeader()) {
 514             createTransaction(CreateTransaction.fromSerializable(message));
 515         } else if (getLeader() != null) {
 516             getLeader().forward(message, getContext());
 517         } else {
 518             getSender().tell(new akka.actor.Status.Failure(new NoShardLeaderException(String.format(
 519                 "Could not find leader for shard %s so transaction cannot be created. This typically happens" +
 520                 " when the system is coming up or recovering and a leader is being elected. Try again" +
 521                 " later.", persistenceId()))), getSelf());
 522         }
 523     }
 524
 525     private void closeTransactionChain(final CloseTransactionChain closeTransactionChain) {
 526         DOMStoreTransactionChain chain =
 527             transactionChains.remove(closeTransactionChain.getTransactionChainId());
 528
 529         if(chain != null) {
 530             chain.close();
 531         }
 532     }
 533
 534     private ActorRef createTypedTransactionActor(int transactionType,
 535             ShardTransactionIdentifier transactionId, String transactionChainId,
 536             short clientVersion ) {
 537
 538         DOMStoreTransactionFactory factory = store;
 539
 540         if(!transactionChainId.isEmpty()) {
 541             factory = transactionChains.get(transactionChainId);
 542             if(factory == null){
 543                 DOMStoreTransactionChain transactionChain = store.createTransactionChain();
 544                 transactionChains.put(transactionChainId, transactionChain);
 545                 factory = transactionChain;
 546             }
 547         }
 548
 549         if(this.schemaContext == null) {
 550             throw new IllegalStateException("SchemaContext is not set");
 551         }
 552
 553         if (transactionType == TransactionProxy.TransactionType.READ_ONLY.ordinal()) {
 554
 555             shardMBean.incrementReadOnlyTransactionCount();
 556
 557             return createShardTransaction(factory.newReadOnlyTransaction(), transactionId, clientVersion);
 558
 559         } else if (transactionType == TransactionProxy.TransactionType.READ_WRITE.ordinal()) {
 560
 561             shardMBean.incrementReadWriteTransactionCount();
 562
 563             return createShardTransaction(factory.newReadWriteTransaction(), transactionId, clientVersion);
 564
 565         } else if (transactionType == TransactionProxy.TransactionType.WRITE_ONLY.ordinal()) {
 566
 567             shardMBean.incrementWriteOnlyTransactionCount();
 568
 569             return createShardTransaction(factory.newWriteOnlyTransaction(), transactionId, clientVersion);
 570         } else {
 571             throw new IllegalArgumentException(
 572                 "Shard="+name + ":CreateTransaction message has unidentified transaction type="
 573                     + transactionType);
 574         }
 575     }
 576
 577     private ActorRef createShardTransaction(DOMStoreTransaction transaction, ShardTransactionIdentifier transactionId,
 578                                             short clientVersion){
 579         return getContext().actorOf(
 580                 ShardTransaction.props(transaction, getSelf(),
 581                         schemaContext, datastoreContext, shardMBean,
 582                         transactionId.getRemoteTransactionId(), clientVersion)
 583                         .withDispatcher(txnDispatcherPath),
 584                 transactionId.toString());
 585
 586     }
 587
 588     private void createTransaction(CreateTransaction createTransaction) {
 589         try {
 590             ActorRef transactionActor = createTransaction(createTransaction.getTransactionType(),
 591                 createTransaction.getTransactionId(), createTransaction.getTransactionChainId(),
 592                 createTransaction.getVersion());
 593
 594             getSender().tell(new CreateTransactionReply(Serialization.serializedActorPath(transactionActor),
 595                     createTransaction.getTransactionId()).toSerializable(), getSelf());
 596         } catch (Exception e) {
 597             getSender().tell(new akka.actor.Status.Failure(e), getSelf());
 598         }
 599     }
 600
 601     private ActorRef createTransaction(int transactionType, String remoteTransactionId,
 602             String transactionChainId, short clientVersion) {
 603
 604         ShardTransactionIdentifier transactionId =
 605             ShardTransactionIdentifier.builder()
 606                 .remoteTransactionId(remoteTransactionId)
 607                 .build();
 608
 609         if(LOG.isDebugEnabled()) {
 610             LOG.debug("{}: Creating transaction : {} ", persistenceId(), transactionId);
 611         }
 612
 613         ActorRef transactionActor = createTypedTransactionActor(transactionType, transactionId,
 614                 transactionChainId, clientVersion);
 615
 616         return transactionActor;
 617     }
 618
 619     private void syncCommitTransaction(final DOMStoreWriteTransaction transaction)
 620         throws ExecutionException, InterruptedException {
 621         DOMStoreThreePhaseCommitCohort commitCohort = transaction.ready();
 622         commitCohort.preCommit().get();
 623         commitCohort.commit().get();
 624     }
 625
 626     private void commitWithNewTransaction(final Modification modification) {
 627         DOMStoreWriteTransaction tx = store.newWriteOnlyTransaction();
 628         modification.apply(tx);
 629         try {
 630             syncCommitTransaction(tx);
 631             shardMBean.incrementCommittedTransactionCount();
 632             shardMBean.setLastCommittedTransactionTime(System.currentTimeMillis());
 633         } catch (InterruptedException | ExecutionException e) {
 634             shardMBean.incrementFailedTransactionsCount();
 635             LOG.error("{}: Failed to commit", persistenceId(), e);
 636         }
 637     }
 638
 639     private void updateSchemaContext(final UpdateSchemaContext message) {
 640         this.schemaContext = message.getSchemaContext();
 641         updateSchemaContext(message.getSchemaContext());
 642         store.onGlobalContextUpdated(message.getSchemaContext());
 643     }
 644
 645     @VisibleForTesting
 646     void updateSchemaContext(final SchemaContext schemaContext) {
 647         store.onGlobalContextUpdated(schemaContext);
 648     }
 649
 650     private void registerChangeListener(final RegisterChangeListener registerChangeListener) {
 651
 652         LOG.debug("{}: registerDataChangeListener for {}", persistenceId(), registerChangeListener.getPath());
 653
 654         ListenerRegistration<AsyncDataChangeListener<YangInstanceIdentifier,
 655                                                      NormalizedNode<?, ?>>> registration;
 656         if(isLeader()) {
 657             registration = doChangeListenerRegistration(registerChangeListener);
 658         } else {
 659             LOG.debug("{}: Shard is not the leader - delaying registration", persistenceId());
 660
 661             DelayedListenerRegistration delayedReg =
 662                     new DelayedListenerRegistration(registerChangeListener);
 663             delayedListenerRegistrations.add(delayedReg);
 664             registration = delayedReg;
 665         }
 666
 667         ActorRef listenerRegistration = getContext().actorOf(
 668                 DataChangeListenerRegistration.props(registration));
 669
 670         LOG.debug("{}: registerDataChangeListener sending reply, listenerRegistrationPath = {} ",
 671                 persistenceId(), listenerRegistration.path());
 672
 673         getSender().tell(new RegisterChangeListenerReply(listenerRegistration.path()), getSelf());
 674     }
 675
 676     private ListenerRegistration<AsyncDataChangeListener<YangInstanceIdentifier,
 677                                                NormalizedNode<?, ?>>> doChangeListenerRegistration(
 678             final RegisterChangeListener registerChangeListener) {
 679
 680         ActorSelection dataChangeListenerPath = getContext().system().actorSelection(
 681                 registerChangeListener.getDataChangeListenerPath());
 682
 683         // Notify the listener if notifications should be enabled or not
 684         // If this shard is the leader then it will enable notifications else
 685         // it will not
 686         dataChangeListenerPath.tell(new EnableNotification(true), getSelf());
 687
 688         // Now store a reference to the data change listener so it can be notified
 689         // at a later point if notifications should be enabled or disabled
 690         dataChangeListeners.add(dataChangeListenerPath);
 691
 692         AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>> listener =
 693                 new DataChangeListenerProxy(dataChangeListenerPath);
 694
 695         LOG.debug("{}: Registering for path {}", persistenceId(), registerChangeListener.getPath());
 696
 697         return store.registerChangeListener(registerChangeListener.getPath(), listener,
 698                 registerChangeListener.getScope());
 699     }
 700
 701     private boolean isMetricsCaptureEnabled(){
 702         CommonConfig config = new CommonConfig(getContext().system().settings().config());
 703         return config.isMetricCaptureEnabled();
 704     }
 705
 706     @Override
 707     protected
 708     void startLogRecoveryBatch(final int maxBatchSize) {
 709         currentLogRecoveryBatch = Lists.newArrayListWithCapacity(maxBatchSize);
 710
 711         if(LOG.isDebugEnabled()) {
 712             LOG.debug("{}: starting log recovery batch with max size {}", persistenceId(), maxBatchSize);
 713         }
 714     }
 715
 716     @Override
 717     protected void appendRecoveredLogEntry(final Payload data) {
 718         if(data instanceof ModificationPayload) {
 719             try {
 720                 currentLogRecoveryBatch.add(((ModificationPayload) data).getModification());
 721             } catch (ClassNotFoundException | IOException e) {
 722                 LOG.error("{}: Error extracting ModificationPayload", persistenceId(), e);
 723             }
 724         } else if (data instanceof CompositeModificationPayload) {
 725             currentLogRecoveryBatch.add(((CompositeModificationPayload) data).getModification());
 726         } else if (data instanceof CompositeModificationByteStringPayload) {
 727             currentLogRecoveryBatch.add(((CompositeModificationByteStringPayload) data).getModification());
 728         } else {
 729             LOG.error("{}: Unknown state received {} during recovery", persistenceId(), data);
 730         }
 731     }
 732
 733     @Override
 734     protected void applyRecoverySnapshot(final byte[] snapshotBytes) {
 735         if(recoveryCoordinator == null) {
 736             recoveryCoordinator = new ShardRecoveryCoordinator(persistenceId(), schemaContext,
 737                     LOG, name.toString());
 738         }
 739
 740         recoveryCoordinator.submit(snapshotBytes, store.newWriteOnlyTransaction());
 741
 742         if(LOG.isDebugEnabled()) {
 743             LOG.debug("{}: submitted recovery sbapshot", persistenceId());
 744         }
 745     }
 746
 747     @Override
 748     protected void applyCurrentLogRecoveryBatch() {
 749         if(recoveryCoordinator == null) {
 750             recoveryCoordinator = new ShardRecoveryCoordinator(persistenceId(), schemaContext,
 751                     LOG, name.toString());
 752         }
 753
 754         recoveryCoordinator.submit(currentLogRecoveryBatch, store.newWriteOnlyTransaction());
 755
 756         if(LOG.isDebugEnabled()) {
 757             LOG.debug("{}: submitted log recovery batch with size {}", persistenceId(),
 758                     currentLogRecoveryBatch.size());
 759         }
 760     }
 761
 762     @Override
 763     protected void onRecoveryComplete() {
 764         if(recoveryCoordinator != null) {
 765             Collection<DOMStoreWriteTransaction> txList = recoveryCoordinator.getTransactions();
 766
 767             if(LOG.isDebugEnabled()) {
 768                 LOG.debug("{}: recovery complete - committing {} Tx's", persistenceId(), txList.size());
 769             }
 770
 771             for(DOMStoreWriteTransaction tx: txList) {
 772                 try {
 773                     syncCommitTransaction(tx);
 774                     shardMBean.incrementCommittedTransactionCount();
 775                 } catch (InterruptedException | ExecutionException e) {
 776                     shardMBean.incrementFailedTransactionsCount();
 777                     LOG.error("{}: Failed to commit", persistenceId(), e);
 778                 }
 779             }
 780         }
 781
 782         recoveryCoordinator = null;
 783         currentLogRecoveryBatch = null;
 784         updateJournalStats();
 785
 786         //notify shard manager
 787         getContext().parent().tell(new ActorInitialized(), getSelf());
 788
 789         // Being paranoid here - this method should only be called once but just in case...
 790         if(txCommitTimeoutCheckSchedule == null) {
 791             // Schedule a message to be periodically sent to check if the current in-progress
 792             // transaction should be expired and aborted.
 793             FiniteDuration period = Duration.create(transactionCommitTimeout / 3, TimeUnit.MILLISECONDS);
 794             txCommitTimeoutCheckSchedule = getContext().system().scheduler().schedule(
 795                     period, period, getSelf(),
 796                     TX_COMMIT_TIMEOUT_CHECK_MESSAGE, getContext().dispatcher(), ActorRef.noSender());
 797         }
 798     }
 799
 800     @Override
 801     protected void applyState(final ActorRef clientActor, final String identifier, final Object data) {
 802
 803         if(data instanceof ModificationPayload) {
 804             try {
 805                 applyModificationToState(clientActor, identifier, ((ModificationPayload) data).getModification());
 806             } catch (ClassNotFoundException | IOException e) {
 807                 LOG.error("{}: Error extracting ModificationPayload", persistenceId(), e);
 808             }
 809         }
 810         else if (data instanceof CompositeModificationPayload) {
 811             Object modification = ((CompositeModificationPayload) data).getModification();
 812
 813             applyModificationToState(clientActor, identifier, modification);
 814         } else if(data instanceof CompositeModificationByteStringPayload ){
 815             Object modification = ((CompositeModificationByteStringPayload) data).getModification();
 816
 817             applyModificationToState(clientActor, identifier, modification);
 818         } else {
 819             LOG.error("{}: Unknown state received {} Class loader = {} CompositeNodeMod.ClassLoader = {}",
 820                     persistenceId(), data, data.getClass().getClassLoader(),
 821                     CompositeModificationPayload.class.getClassLoader());
 822         }
 823
 824         updateJournalStats();
 825
 826     }
 827
 828     private void applyModificationToState(ActorRef clientActor, String identifier, Object modification) {
 829         if(modification == null) {
 830             LOG.error(
 831                     "{}: modification is null - this is very unexpected, clientActor = {}, identifier = {}",
 832                     persistenceId(), identifier, clientActor != null ? clientActor.path().toString() : null);
 833         } else if(clientActor == null) {
 834             // There's no clientActor to which to send a commit reply so we must be applying
 835             // replicated state from the leader.
 836             commitWithNewTransaction(MutableCompositeModification.fromSerializable(modification));
 837         } else {
 838             // This must be the OK to commit after replication consensus.
 839             finishCommit(clientActor, identifier);
 840         }
 841     }
 842
 843     private void updateJournalStats() {
 844         ReplicatedLogEntry lastLogEntry = getLastLogEntry();
 845
 846         if (lastLogEntry != null) {
 847             shardMBean.setLastLogIndex(lastLogEntry.getIndex());
 848             shardMBean.setLastLogTerm(lastLogEntry.getTerm());
 849         }
 850
 851         shardMBean.setCommitIndex(getCommitIndex());
 852         shardMBean.setLastApplied(getLastApplied());
 853         shardMBean.setInMemoryJournalDataSize(getRaftActorContext().getReplicatedLog().dataSize());
 854     }
 855
 856     @Override
 857     protected void createSnapshot() {
 858         // Create a transaction actor. We are really going to treat the transaction as a worker
 859         // so that this actor does not get block building the snapshot. THe transaction actor will
 860         // after processing the CreateSnapshot message.
 861
 862         ActorRef createSnapshotTransaction = createTransaction(
 863                 TransactionProxy.TransactionType.READ_ONLY.ordinal(),
 864                 "createSnapshot" + ++createSnapshotTransactionCounter, "",
 865                 DataStoreVersions.CURRENT_VERSION);
 866
 867         createSnapshotTransaction.tell(CreateSnapshot.INSTANCE, self());
 868     }
 869
 870     @VisibleForTesting
 871     @Override
 872     protected void applySnapshot(final byte[] snapshotBytes) {
 873         // Since this will be done only on Recovery or when this actor is a Follower
 874         // we can safely commit everything in here. We not need to worry about event notifications
 875         // as they would have already been disabled on the follower
 876
 877         LOG.info("{}: Applying snapshot", persistenceId());
 878         try {
 879             DOMStoreWriteTransaction transaction = store.newWriteOnlyTransaction();
 880
 881             NormalizedNode<?, ?> node = SerializationUtils.deserializeNormalizedNode(snapshotBytes);
 882
 883             // delete everything first
 884             transaction.delete(DATASTORE_ROOT);
 885
 886             // Add everything from the remote node back
 887             transaction.write(DATASTORE_ROOT, node);
 888             syncCommitTransaction(transaction);
 889         } catch (InterruptedException | ExecutionException e) {
 890             LOG.error("{}: An exception occurred when applying snapshot", persistenceId(), e);
 891         } finally {
 892             LOG.info("{}: Done applying snapshot", persistenceId());
 893         }
 894     }
 895
 896     @Override
 897     protected void onStateChanged() {
 898         boolean isLeader = isLeader();
 899         for (ActorSelection dataChangeListener : dataChangeListeners) {
 900             dataChangeListener.tell(new EnableNotification(isLeader), getSelf());
 901         }
 902
 903         if(isLeader) {
 904             for(DelayedListenerRegistration reg: delayedListenerRegistrations) {
 905                 if(!reg.isClosed()) {
 906                     reg.setDelegate(doChangeListenerRegistration(reg.getRegisterChangeListener()));
 907                 }
 908             }
 909
 910             delayedListenerRegistrations.clear();
 911         }
 912
 913         shardMBean.setRaftState(getRaftState().name());
 914         shardMBean.setCurrentTerm(getCurrentTerm());
 915
 916         // If this actor is no longer the leader close all the transaction chains
 917         if(!isLeader){
 918             for(Map.Entry<String, DOMStoreTransactionChain> entry : transactionChains.entrySet()){
 919                 if(LOG.isDebugEnabled()) {
 920                     LOG.debug(
 921                         "{}: onStateChanged: Closing transaction chain {} because shard {} is no longer the leader",
 922                         persistenceId(), entry.getKey(), getId());
 923                 }
 924                 entry.getValue().close();
 925             }
 926
 927             transactionChains.clear();
 928         }
 929     }
 930
 931     @Override
 932     protected DataPersistenceProvider persistence() {
 933         return dataPersistenceProvider;
 934     }
 935
 936     @Override protected void onLeaderChanged(final String oldLeader, final String newLeader) {
 937         shardMBean.setLeader(newLeader);
 938     }
 939
 940     @Override public String persistenceId() {
 941         return this.name.toString();
 942     }
 943
 944     @VisibleForTesting
 945     DataPersistenceProvider getDataPersistenceProvider() {
 946         return dataPersistenceProvider;
 947     }
 948
 949     private static class ShardCreator implements Creator<Shard> {
 950
 951         private static final long serialVersionUID = 1L;
 952
 953         final ShardIdentifier name;
 954         final Map<ShardIdentifier, String> peerAddresses;
 955         final DatastoreContext datastoreContext;
 956         final SchemaContext schemaContext;
 957
 958         ShardCreator(final ShardIdentifier name, final Map<ShardIdentifier, String> peerAddresses,
 959                 final DatastoreContext datastoreContext, final SchemaContext schemaContext) {
 960             this.name = name;
 961             this.peerAddresses = peerAddresses;
 962             this.datastoreContext = datastoreContext;
 963             this.schemaContext = schemaContext;
 964         }
 965
 966         @Override
 967         public Shard create() throws Exception {
 968             return new Shard(name, peerAddresses, datastoreContext, schemaContext);
 969         }
 970     }
 971
 972     @VisibleForTesting
 973     InMemoryDOMDataStore getDataStore() {
 974         return store;
 975     }
 976
 977     @VisibleForTesting
 978     ShardStats getShardMBean() {
 979         return shardMBean;
 980     }
 981
 982     private static class DelayedListenerRegistration implements
 983         ListenerRegistration<AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>>> {
 984
 985         private volatile boolean closed;
 986
 987         private final RegisterChangeListener registerChangeListener;
 988
 989         private volatile ListenerRegistration<AsyncDataChangeListener<YangInstanceIdentifier,
 990                                                              NormalizedNode<?, ?>>> delegate;
 991
 992         DelayedListenerRegistration(final RegisterChangeListener registerChangeListener) {
 993             this.registerChangeListener = registerChangeListener;
 994         }
 995
 996         void setDelegate( final ListenerRegistration<AsyncDataChangeListener<YangInstanceIdentifier,
 997                                             NormalizedNode<?, ?>>> registration) {
 998             this.delegate = registration;
 999         }
1000
1001         boolean isClosed() {
1002             return closed;
1003         }
1004
1005         RegisterChangeListener getRegisterChangeListener() {
1006             return registerChangeListener;
1007         }
1008
1009         @Override
1010         public AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>> getInstance() {
1011             return delegate != null ? delegate.getInstance() : null;
1012         }
1013
1014         @Override
1015         public void close() {
1016             closed = true;
1017             if(delegate != null) {
1018                 delegate.close();
1019             }
1020         }
1021     }
1022 }