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

   1 /*
   2  * Copyright (c) 2014 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8
   9 package org.opendaylight.controller.cluster.datastore;
  10
  11 import akka.actor.ActorRef;
  12 import akka.actor.ActorSelection;
  13 import akka.actor.Cancellable;
  14 import akka.actor.PoisonPill;
  15 import akka.actor.Props;
  16 import akka.event.Logging;
  17 import akka.event.LoggingAdapter;
  18 import akka.japi.Creator;
  19 import akka.persistence.RecoveryFailure;
  20 import akka.serialization.Serialization;
  21 import com.google.common.annotations.VisibleForTesting;
  22 import com.google.common.base.Optional;
  23 import com.google.common.base.Preconditions;
  24 import com.google.common.collect.Lists;
  25 import com.google.common.util.concurrent.FutureCallback;
  26 import com.google.common.util.concurrent.Futures;
  27 import com.google.common.util.concurrent.ListenableFuture;
  28 import com.google.protobuf.ByteString;
  29 import com.google.protobuf.InvalidProtocolBufferException;
  30 import java.util.Collection;
  31 import java.util.HashMap;
  32 import java.util.List;
  33 import java.util.Map;
  34 import java.util.concurrent.ExecutionException;
  35 import java.util.concurrent.TimeUnit;
  36 import javax.annotation.Nonnull;
  37 import org.opendaylight.controller.cluster.DataPersistenceProvider;
  38 import org.opendaylight.controller.cluster.common.actor.CommonConfig;
  39 import org.opendaylight.controller.cluster.common.actor.MeteringBehavior;
  40 import org.opendaylight.controller.cluster.datastore.ShardCommitCoordinator.CohortEntry;
  41 import org.opendaylight.controller.cluster.datastore.compat.BackwardsCompatibleThreePhaseCommitCohort;
  42 import org.opendaylight.controller.cluster.datastore.exceptions.NoShardLeaderException;
  43 import org.opendaylight.controller.cluster.datastore.identifiers.ShardIdentifier;
  44 import org.opendaylight.controller.cluster.datastore.identifiers.ShardTransactionIdentifier;
  45 import org.opendaylight.controller.cluster.datastore.jmx.mbeans.shard.ShardMBeanFactory;
  46 import org.opendaylight.controller.cluster.datastore.jmx.mbeans.shard.ShardStats;
  47 import org.opendaylight.controller.cluster.datastore.messages.AbortTransaction;
  48 import org.opendaylight.controller.cluster.datastore.messages.AbortTransactionReply;
  49 import org.opendaylight.controller.cluster.datastore.messages.ActorInitialized;
  50 import org.opendaylight.controller.cluster.datastore.messages.CanCommitTransaction;
  51 import org.opendaylight.controller.cluster.datastore.messages.CloseTransactionChain;
  52 import org.opendaylight.controller.cluster.datastore.messages.CommitTransaction;
  53 import org.opendaylight.controller.cluster.datastore.messages.CommitTransactionReply;
  54 import org.opendaylight.controller.cluster.datastore.messages.CreateTransaction;
  55 import org.opendaylight.controller.cluster.datastore.messages.CreateTransactionReply;
  56 import org.opendaylight.controller.cluster.datastore.messages.EnableNotification;
  57 import org.opendaylight.controller.cluster.datastore.messages.ForwardedReadyTransaction;
  58 import org.opendaylight.controller.cluster.datastore.messages.PeerAddressResolved;
  59 import org.opendaylight.controller.cluster.datastore.messages.ReadData;
  60 import org.opendaylight.controller.cluster.datastore.messages.ReadDataReply;
  61 import org.opendaylight.controller.cluster.datastore.messages.ReadyTransactionReply;
  62 import org.opendaylight.controller.cluster.datastore.messages.RegisterChangeListener;
  63 import org.opendaylight.controller.cluster.datastore.messages.RegisterChangeListenerReply;
  64 import org.opendaylight.controller.cluster.datastore.messages.UpdateSchemaContext;
  65 import org.opendaylight.controller.cluster.datastore.modification.Modification;
  66 import org.opendaylight.controller.cluster.datastore.modification.MutableCompositeModification;
  67 import org.opendaylight.controller.cluster.datastore.node.NormalizedNodeToNodeCodec;
  68 import org.opendaylight.controller.cluster.raft.RaftActor;
  69 import org.opendaylight.controller.cluster.raft.ReplicatedLogEntry;
  70 import org.opendaylight.controller.cluster.raft.base.messages.CaptureSnapshotReply;
  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.protobuff.messages.common.NormalizedNodeMessages;
  77 import org.opendaylight.controller.sal.core.spi.data.DOMStoreThreePhaseCommitCohort;
  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 Object COMMIT_TRANSACTION_REPLY = new CommitTransactionReply().toSerializable();
  97
  98     private static final Object TX_COMMIT_TIMEOUT_CHECK_MESSAGE = "txCommitTimeoutCheck";
  99
 100     public static final String DEFAULT_NAME = "default";
 101
 102     // The state of this Shard
 103     private final InMemoryDOMDataStore store;
 104
 105     private final LoggingAdapter LOG =
 106         Logging.getLogger(getContext().system(), this);
 107
 108     /// The name of this shard
 109     private final ShardIdentifier name;
 110
 111     private final ShardStats shardMBean;
 112
 113     private final List<ActorSelection> dataChangeListeners =  Lists.newArrayList();
 114
 115     private final List<DelayedListenerRegistration> delayedListenerRegistrations =
 116                                                                        Lists.newArrayList();
 117
 118     private final DatastoreContext datastoreContext;
 119
 120     private final DataPersistenceProvider dataPersistenceProvider;
 121
 122     private SchemaContext schemaContext;
 123
 124     private ActorRef createSnapshotTransaction;
 125
 126     private int createSnapshotTransactionCounter;
 127
 128     private final ShardCommitCoordinator commitCoordinator;
 129
 130     private final long transactionCommitTimeout;
 131
 132     private Cancellable txCommitTimeoutCheckSchedule;
 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     protected Shard(ShardIdentifier name, Map<ShardIdentifier, String> peerAddresses,
 143             DatastoreContext datastoreContext, SchemaContext schemaContext) {
 144         super(name.toString(), mapPeerAddresses(peerAddresses),
 145                 Optional.of(datastoreContext.getShardRaftConfig()));
 146
 147         this.name = name;
 148         this.datastoreContext = datastoreContext;
 149         this.schemaContext = schemaContext;
 150         this.dataPersistenceProvider = (datastoreContext.isPersistent()) ? new PersistentDataProvider() : new NonPersistentRaftDataProvider();
 151
 152         LOG.info("Shard created : {} persistent : {}", name, datastoreContext.isPersistent());
 153
 154         store = InMemoryDOMDataStoreFactory.create(name.toString(), null,
 155                 datastoreContext.getDataStoreProperties());
 156
 157         if(schemaContext != null) {
 158             store.onGlobalContextUpdated(schemaContext);
 159         }
 160
 161         shardMBean = ShardMBeanFactory.getShardStatsMBean(name.toString(),
 162                 datastoreContext.getDataStoreMXBeanType());
 163         shardMBean.setDataStoreExecutor(store.getDomStoreExecutor());
 164         shardMBean.setNotificationManager(store.getDataChangeListenerNotificationManager());
 165
 166         if (isMetricsCaptureEnabled()) {
 167             getContext().become(new MeteringBehavior(this));
 168         }
 169
 170         commitCoordinator = new ShardCommitCoordinator(TimeUnit.SECONDS.convert(1, TimeUnit.MINUTES),
 171                 datastoreContext.getShardTransactionCommitQueueCapacity());
 172
 173         transactionCommitTimeout = TimeUnit.MILLISECONDS.convert(
 174                 datastoreContext.getShardTransactionCommitTimeoutInSeconds(), TimeUnit.SECONDS);
 175     }
 176
 177     private static Map<String, String> mapPeerAddresses(
 178         Map<ShardIdentifier, String> peerAddresses) {
 179         Map<String, String> map = new HashMap<>();
 180
 181         for (Map.Entry<ShardIdentifier, String> entry : peerAddresses
 182             .entrySet()) {
 183             map.put(entry.getKey().toString(), entry.getValue());
 184         }
 185
 186         return map;
 187     }
 188
 189     public static Props props(final ShardIdentifier name,
 190         final Map<ShardIdentifier, String> peerAddresses,
 191         DatastoreContext datastoreContext, SchemaContext schemaContext) {
 192         Preconditions.checkNotNull(name, "name should not be null");
 193         Preconditions.checkNotNull(peerAddresses, "peerAddresses should not be null");
 194         Preconditions.checkNotNull(datastoreContext, "dataStoreContext should not be null");
 195         Preconditions.checkNotNull(schemaContext, "schemaContext should not be null");
 196
 197         return Props.create(new ShardCreator(name, peerAddresses, datastoreContext, schemaContext));
 198     }
 199
 200     @Override
 201     public void postStop() {
 202         super.postStop();
 203
 204         if(txCommitTimeoutCheckSchedule != null) {
 205             txCommitTimeoutCheckSchedule.cancel();
 206         }
 207     }
 208
 209     @Override
 210     public void onReceiveRecover(Object message) throws Exception {
 211         if(LOG.isDebugEnabled()) {
 212             LOG.debug("onReceiveRecover: Received message {} from {}",
 213                 message.getClass().toString(),
 214                 getSender());
 215         }
 216
 217         if (message instanceof RecoveryFailure){
 218             LOG.error(((RecoveryFailure) message).cause(), "Recovery failed because of this cause");
 219
 220             // Even though recovery failed, we still need to finish our recovery, eg send the
 221             // ActorInitialized message and start the txCommitTimeoutCheckSchedule.
 222             onRecoveryComplete();
 223         } else {
 224             super.onReceiveRecover(message);
 225         }
 226     }
 227
 228     @Override
 229     public void onReceiveCommand(Object message) throws Exception {
 230         if(LOG.isDebugEnabled()) {
 231             LOG.debug("onReceiveCommand: Received message {} from {}", message, getSender());
 232         }
 233
 234         if(message.getClass().equals(ReadDataReply.SERIALIZABLE_CLASS)) {
 235             handleReadDataReply(message);
 236         } else if (message.getClass().equals(CreateTransaction.SERIALIZABLE_CLASS)) {
 237             handleCreateTransaction(message);
 238         } else if(message instanceof ForwardedReadyTransaction) {
 239             handleForwardedReadyTransaction((ForwardedReadyTransaction)message);
 240         } else if(message.getClass().equals(CanCommitTransaction.SERIALIZABLE_CLASS)) {
 241             handleCanCommitTransaction(CanCommitTransaction.fromSerializable(message));
 242         } else if(message.getClass().equals(CommitTransaction.SERIALIZABLE_CLASS)) {
 243             handleCommitTransaction(CommitTransaction.fromSerializable(message));
 244         } else if(message.getClass().equals(AbortTransaction.SERIALIZABLE_CLASS)) {
 245             handleAbortTransaction(AbortTransaction.fromSerializable(message));
 246         } else if (message.getClass().equals(CloseTransactionChain.SERIALIZABLE_CLASS)){
 247             closeTransactionChain(CloseTransactionChain.fromSerializable(message));
 248         } else if (message instanceof RegisterChangeListener) {
 249             registerChangeListener((RegisterChangeListener) message);
 250         } else if (message instanceof UpdateSchemaContext) {
 251             updateSchemaContext((UpdateSchemaContext) message);
 252         } else if (message instanceof PeerAddressResolved) {
 253             PeerAddressResolved resolved = (PeerAddressResolved) message;
 254             setPeerAddress(resolved.getPeerId().toString(),
 255                 resolved.getPeerAddress());
 256         } else if(message.equals(TX_COMMIT_TIMEOUT_CHECK_MESSAGE)) {
 257             handleTransactionCommitTimeoutCheck();
 258         } else {
 259             super.onReceiveCommand(message);
 260         }
 261     }
 262
 263     private void handleTransactionCommitTimeoutCheck() {
 264         CohortEntry cohortEntry = commitCoordinator.getCurrentCohortEntry();
 265         if(cohortEntry != null) {
 266             long elapsed = System.currentTimeMillis() - cohortEntry.getLastAccessTime();
 267             if(elapsed > transactionCommitTimeout) {
 268                 LOG.warning("Current transaction {} has timed out after {} ms - aborting",
 269                         cohortEntry.getTransactionID(), transactionCommitTimeout);
 270
 271                 doAbortTransaction(cohortEntry.getTransactionID(), null);
 272             }
 273         }
 274     }
 275
 276     private void handleCommitTransaction(CommitTransaction commit) {
 277         final String transactionID = commit.getTransactionID();
 278
 279         LOG.debug("Committing transaction {}", transactionID);
 280
 281         // Get the current in-progress cohort entry in the commitCoordinator if it corresponds to
 282         // this transaction.
 283         final CohortEntry cohortEntry = commitCoordinator.getCohortEntryIfCurrent(transactionID);
 284         if(cohortEntry == null) {
 285             // We're not the current Tx - the Tx was likely expired b/c it took too long in
 286             // between the canCommit and commit messages.
 287             IllegalStateException ex = new IllegalStateException(
 288                     String.format("Cannot commit transaction %s - it is not the current transaction",
 289                             transactionID));
 290             LOG.error(ex.getMessage());
 291             shardMBean.incrementFailedTransactionsCount();
 292             getSender().tell(new akka.actor.Status.Failure(ex), getSelf());
 293             return;
 294         }
 295
 296         // We perform the preCommit phase here atomically with the commit phase. This is an
 297         // optimization to eliminate the overhead of an extra preCommit message. We lose front-end
 298         // coordination of preCommit across shards in case of failure but preCommit should not
 299         // normally fail since we ensure only one concurrent 3-phase commit.
 300
 301         try {
 302             // We block on the future here so we don't have to worry about possibly accessing our
 303             // state on a different thread outside of our dispatcher. Also, the data store
 304             // currently uses a same thread executor anyway.
 305             cohortEntry.getCohort().preCommit().get();
 306
 307             Shard.this.persistData(getSender(), transactionID,
 308                     new CompositeModificationPayload(cohortEntry.getModification().toSerializable()));
 309         } catch (InterruptedException | ExecutionException e) {
 310             LOG.error(e, "An exception occurred while preCommitting transaction {}",
 311                     cohortEntry.getTransactionID());
 312             shardMBean.incrementFailedTransactionsCount();
 313             getSender().tell(new akka.actor.Status.Failure(e), getSelf());
 314         }
 315
 316         cohortEntry.updateLastAccessTime();
 317     }
 318
 319     private void finishCommit(@Nonnull final ActorRef sender, final @Nonnull String transactionID) {
 320         // With persistence enabled, this method is called via applyState by the leader strategy
 321         // after the commit has been replicated to a majority of the followers.
 322
 323         CohortEntry cohortEntry = commitCoordinator.getCohortEntryIfCurrent(transactionID);
 324         if(cohortEntry == null) {
 325             // The transaction is no longer the current commit. This can happen if the transaction
 326             // was aborted prior, most likely due to timeout in the front-end. We need to finish
 327             // committing the transaction though since it was successfully persisted and replicated
 328             // however we can't use the original cohort b/c it was already preCommitted and may
 329             // conflict with the current commit or may have been aborted so we commit with a new
 330             // transaction.
 331             cohortEntry = commitCoordinator.getAndRemoveCohortEntry(transactionID);
 332             if(cohortEntry != null) {
 333                 commitWithNewTransaction(cohortEntry.getModification());
 334                 sender.tell(COMMIT_TRANSACTION_REPLY, getSelf());
 335             } else {
 336                 // This really shouldn't happen - it likely means that persistence or replication
 337                 // took so long to complete such that the cohort entry was expired from the cache.
 338                 IllegalStateException ex = new IllegalStateException(
 339                         String.format("Could not finish committing transaction %s - no CohortEntry found",
 340                                 transactionID));
 341                 LOG.error(ex.getMessage());
 342                 sender.tell(new akka.actor.Status.Failure(ex), getSelf());
 343             }
 344
 345             return;
 346         }
 347
 348         LOG.debug("Finishing commit for transaction {}", cohortEntry.getTransactionID());
 349
 350         try {
 351             // We block on the future here so we don't have to worry about possibly accessing our
 352             // state on a different thread outside of our dispatcher. Also, the data store
 353             // currently uses a same thread executor anyway.
 354             cohortEntry.getCohort().commit().get();
 355
 356             sender.tell(COMMIT_TRANSACTION_REPLY, getSelf());
 357
 358             shardMBean.incrementCommittedTransactionCount();
 359             shardMBean.setLastCommittedTransactionTime(System.currentTimeMillis());
 360
 361         } catch (InterruptedException | ExecutionException e) {
 362             sender.tell(new akka.actor.Status.Failure(e), getSelf());
 363
 364             LOG.error(e, "An exception occurred while committing transaction {}", transactionID);
 365             shardMBean.incrementFailedTransactionsCount();
 366         }
 367
 368         commitCoordinator.currentTransactionComplete(transactionID, true);
 369     }
 370
 371     private void handleCanCommitTransaction(CanCommitTransaction canCommit) {
 372         LOG.debug("Can committing transaction {}", canCommit.getTransactionID());
 373         commitCoordinator.handleCanCommit(canCommit, getSender(), self());
 374     }
 375
 376     private void handleForwardedReadyTransaction(ForwardedReadyTransaction ready) {
 377         LOG.debug("Readying transaction {}, client version {}", ready.getTransactionID(),
 378                 ready.getTxnClientVersion());
 379
 380         // This message is forwarded by the ShardTransaction on ready. We cache the cohort in the
 381         // commitCoordinator in preparation for the subsequent three phase commit initiated by
 382         // the front-end.
 383         commitCoordinator.transactionReady(ready.getTransactionID(), ready.getCohort(),
 384                 ready.getModification());
 385
 386         // Return our actor path as we'll handle the three phase commit, except if the Tx client
 387         // version < 1 (Helium-1 version). This means the Tx was initiated by a base Helium version
 388         // node. In that case, the subsequent 3-phase commit messages won't contain the
 389         // transactionId so to maintain backwards compatibility, we create a separate cohort actor
 390         // to provide the compatible behavior.
 391         ActorRef replyActorPath = self();
 392         if(ready.getTxnClientVersion() < CreateTransaction.HELIUM_1_VERSION) {
 393             LOG.debug("Creating BackwardsCompatibleThreePhaseCommitCohort");
 394             replyActorPath = getContext().actorOf(BackwardsCompatibleThreePhaseCommitCohort.props(
 395                     ready.getTransactionID()));
 396         }
 397
 398         ReadyTransactionReply readyTransactionReply = new ReadyTransactionReply(
 399                 Serialization.serializedActorPath(replyActorPath));
 400         getSender().tell(ready.isReturnSerialized() ? readyTransactionReply.toSerializable() :
 401                 readyTransactionReply, getSelf());
 402     }
 403
 404     private void handleAbortTransaction(AbortTransaction abort) {
 405         doAbortTransaction(abort.getTransactionID(), getSender());
 406     }
 407
 408     private void doAbortTransaction(String transactionID, final ActorRef sender) {
 409         final CohortEntry cohortEntry = commitCoordinator.getCohortEntryIfCurrent(transactionID);
 410         if(cohortEntry != null) {
 411             LOG.debug("Aborting transaction {}", transactionID);
 412
 413             // We don't remove the cached cohort entry here (ie pass false) in case the Tx was
 414             // aborted during replication in which case we may still commit locally if replication
 415             // succeeds.
 416             commitCoordinator.currentTransactionComplete(transactionID, false);
 417
 418             final ListenableFuture<Void> future = cohortEntry.getCohort().abort();
 419             final ActorRef self = getSelf();
 420
 421             Futures.addCallback(future, new FutureCallback<Void>() {
 422                 @Override
 423                 public void onSuccess(Void v) {
 424                     shardMBean.incrementAbortTransactionsCount();
 425
 426                     if(sender != null) {
 427                         sender.tell(new AbortTransactionReply().toSerializable(), self);
 428                     }
 429                 }
 430
 431                 @Override
 432                 public void onFailure(Throwable t) {
 433                     LOG.error(t, "An exception happened during abort");
 434
 435                     if(sender != null) {
 436                         sender.tell(new akka.actor.Status.Failure(t), self);
 437                     }
 438                 }
 439             });
 440         }
 441     }
 442
 443     private void handleCreateTransaction(Object message) {
 444         if (isLeader()) {
 445             createTransaction(CreateTransaction.fromSerializable(message));
 446         } else if (getLeader() != null) {
 447             getLeader().forward(message, getContext());
 448         } else {
 449             getSender().tell(new akka.actor.Status.Failure(new NoShardLeaderException(
 450                 "Could not find shard leader so transaction cannot be created. This typically happens" +
 451                 " when the system is coming up or recovering and a leader is being elected. Try again" +
 452                 " later.")), getSelf());
 453         }
 454     }
 455
 456     private void handleReadDataReply(Object message) {
 457         // This must be for install snapshot. Don't want to open this up and trigger
 458         // deSerialization
 459
 460         self().tell(new CaptureSnapshotReply(ReadDataReply.getNormalizedNodeByteString(message)),
 461                 self());
 462
 463         createSnapshotTransaction = null;
 464
 465         // Send a PoisonPill instead of sending close transaction because we do not really need
 466         // a response
 467         getSender().tell(PoisonPill.getInstance(), self());
 468     }
 469
 470     private void closeTransactionChain(CloseTransactionChain closeTransactionChain) {
 471         DOMStoreTransactionChain chain =
 472             transactionChains.remove(closeTransactionChain.getTransactionChainId());
 473
 474         if(chain != null) {
 475             chain.close();
 476         }
 477     }
 478
 479     private ActorRef createTypedTransactionActor(int transactionType,
 480             ShardTransactionIdentifier transactionId, String transactionChainId, int clientVersion ) {
 481
 482         DOMStoreTransactionFactory factory = store;
 483
 484         if(!transactionChainId.isEmpty()) {
 485             factory = transactionChains.get(transactionChainId);
 486             if(factory == null){
 487                 DOMStoreTransactionChain transactionChain = store.createTransactionChain();
 488                 transactionChains.put(transactionChainId, transactionChain);
 489                 factory = transactionChain;
 490             }
 491         }
 492
 493         if(this.schemaContext == null) {
 494             throw new IllegalStateException("SchemaContext is not set");
 495         }
 496
 497         if (transactionType == TransactionProxy.TransactionType.READ_ONLY.ordinal()) {
 498
 499             shardMBean.incrementReadOnlyTransactionCount();
 500
 501             return getContext().actorOf(
 502                 ShardTransaction.props(factory.newReadOnlyTransaction(), getSelf(),
 503                         schemaContext,datastoreContext, shardMBean,
 504                         transactionId.getRemoteTransactionId(), clientVersion),
 505                         transactionId.toString());
 506
 507         } else if (transactionType == TransactionProxy.TransactionType.READ_WRITE.ordinal()) {
 508
 509             shardMBean.incrementReadWriteTransactionCount();
 510
 511             return getContext().actorOf(
 512                 ShardTransaction.props(factory.newReadWriteTransaction(), getSelf(),
 513                         schemaContext, datastoreContext, shardMBean,
 514                         transactionId.getRemoteTransactionId(), clientVersion),
 515                         transactionId.toString());
 516
 517
 518         } else if (transactionType == TransactionProxy.TransactionType.WRITE_ONLY.ordinal()) {
 519
 520             shardMBean.incrementWriteOnlyTransactionCount();
 521
 522             return getContext().actorOf(
 523                 ShardTransaction.props(factory.newWriteOnlyTransaction(), getSelf(),
 524                         schemaContext, datastoreContext, shardMBean,
 525                         transactionId.getRemoteTransactionId(), clientVersion),
 526                         transactionId.toString());
 527         } else {
 528             throw new IllegalArgumentException(
 529                 "Shard="+name + ":CreateTransaction message has unidentified transaction type="
 530                     + transactionType);
 531         }
 532     }
 533
 534     private void createTransaction(CreateTransaction createTransaction) {
 535         try {
 536             ActorRef transactionActor = createTransaction(createTransaction.getTransactionType(),
 537                 createTransaction.getTransactionId(), createTransaction.getTransactionChainId(),
 538                 createTransaction.getVersion());
 539
 540             getSender().tell(new CreateTransactionReply(Serialization.serializedActorPath(transactionActor),
 541                     createTransaction.getTransactionId()).toSerializable(), getSelf());
 542         } catch (Exception e) {
 543             getSender().tell(new akka.actor.Status.Failure(e), getSelf());
 544         }
 545     }
 546
 547     private ActorRef createTransaction(int transactionType, String remoteTransactionId,
 548             String transactionChainId, int clientVersion) {
 549
 550         ShardTransactionIdentifier transactionId =
 551             ShardTransactionIdentifier.builder()
 552                 .remoteTransactionId(remoteTransactionId)
 553                 .build();
 554
 555         if(LOG.isDebugEnabled()) {
 556             LOG.debug("Creating transaction : {} ", transactionId);
 557         }
 558
 559         ActorRef transactionActor = createTypedTransactionActor(transactionType, transactionId,
 560                 transactionChainId, clientVersion);
 561
 562         return transactionActor;
 563     }
 564
 565     private void syncCommitTransaction(DOMStoreWriteTransaction transaction)
 566         throws ExecutionException, InterruptedException {
 567         DOMStoreThreePhaseCommitCohort commitCohort = transaction.ready();
 568         commitCohort.preCommit().get();
 569         commitCohort.commit().get();
 570     }
 571
 572     private void commitWithNewTransaction(Modification modification) {
 573         DOMStoreWriteTransaction tx = store.newWriteOnlyTransaction();
 574         modification.apply(tx);
 575         try {
 576             syncCommitTransaction(tx);
 577             shardMBean.incrementCommittedTransactionCount();
 578             shardMBean.setLastCommittedTransactionTime(System.currentTimeMillis());
 579         } catch (InterruptedException | ExecutionException e) {
 580             shardMBean.incrementFailedTransactionsCount();
 581             LOG.error(e, "Failed to commit");
 582         }
 583     }
 584
 585     private void updateSchemaContext(UpdateSchemaContext message) {
 586         this.schemaContext = message.getSchemaContext();
 587         updateSchemaContext(message.getSchemaContext());
 588         store.onGlobalContextUpdated(message.getSchemaContext());
 589     }
 590
 591     @VisibleForTesting
 592     void updateSchemaContext(SchemaContext schemaContext) {
 593         store.onGlobalContextUpdated(schemaContext);
 594     }
 595
 596     private void registerChangeListener(RegisterChangeListener registerChangeListener) {
 597
 598         LOG.debug("registerDataChangeListener for {}", registerChangeListener.getPath());
 599
 600         ListenerRegistration<AsyncDataChangeListener<YangInstanceIdentifier,
 601                                                      NormalizedNode<?, ?>>> registration;
 602         if(isLeader()) {
 603             registration = doChangeListenerRegistration(registerChangeListener);
 604         } else {
 605             LOG.debug("Shard is not the leader - delaying registration");
 606
 607             DelayedListenerRegistration delayedReg =
 608                     new DelayedListenerRegistration(registerChangeListener);
 609             delayedListenerRegistrations.add(delayedReg);
 610             registration = delayedReg;
 611         }
 612
 613         ActorRef listenerRegistration = getContext().actorOf(
 614                 DataChangeListenerRegistration.props(registration));
 615
 616         LOG.debug("registerDataChangeListener sending reply, listenerRegistrationPath = {} ",
 617                     listenerRegistration.path());
 618
 619         getSender().tell(new RegisterChangeListenerReply(listenerRegistration.path()), getSelf());
 620     }
 621
 622     private ListenerRegistration<AsyncDataChangeListener<YangInstanceIdentifier,
 623                                                NormalizedNode<?, ?>>> doChangeListenerRegistration(
 624             RegisterChangeListener registerChangeListener) {
 625
 626         ActorSelection dataChangeListenerPath = getContext().system().actorSelection(
 627                 registerChangeListener.getDataChangeListenerPath());
 628
 629         // Notify the listener if notifications should be enabled or not
 630         // If this shard is the leader then it will enable notifications else
 631         // it will not
 632         dataChangeListenerPath.tell(new EnableNotification(true), getSelf());
 633
 634         // Now store a reference to the data change listener so it can be notified
 635         // at a later point if notifications should be enabled or disabled
 636         dataChangeListeners.add(dataChangeListenerPath);
 637
 638         AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>> listener =
 639                 new DataChangeListenerProxy(schemaContext, dataChangeListenerPath);
 640
 641         LOG.debug("Registering for path {}", registerChangeListener.getPath());
 642
 643         return store.registerChangeListener(registerChangeListener.getPath(), listener,
 644                 registerChangeListener.getScope());
 645     }
 646
 647     private boolean isMetricsCaptureEnabled(){
 648         CommonConfig config = new CommonConfig(getContext().system().settings().config());
 649         return config.isMetricCaptureEnabled();
 650     }
 651
 652     @Override
 653     protected
 654     void startLogRecoveryBatch(int maxBatchSize) {
 655         currentLogRecoveryBatch = Lists.newArrayListWithCapacity(maxBatchSize);
 656
 657         if(LOG.isDebugEnabled()) {
 658             LOG.debug("{} : starting log recovery batch with max size {}", persistenceId(), maxBatchSize);
 659         }
 660     }
 661
 662     @Override
 663     protected void appendRecoveredLogEntry(Payload data) {
 664         if (data instanceof CompositeModificationPayload) {
 665             currentLogRecoveryBatch.add(((CompositeModificationPayload) data).getModification());
 666         } else {
 667             LOG.error("Unknown state received {} during recovery", data);
 668         }
 669     }
 670
 671     @Override
 672     protected void applyRecoverySnapshot(ByteString snapshot) {
 673         if(recoveryCoordinator == null) {
 674             recoveryCoordinator = new ShardRecoveryCoordinator(persistenceId(), schemaContext);
 675         }
 676
 677         recoveryCoordinator.submit(snapshot, store.newWriteOnlyTransaction());
 678
 679         if(LOG.isDebugEnabled()) {
 680             LOG.debug("{} : submitted recovery sbapshot", persistenceId());
 681         }
 682     }
 683
 684     @Override
 685     protected void applyCurrentLogRecoveryBatch() {
 686         if(recoveryCoordinator == null) {
 687             recoveryCoordinator = new ShardRecoveryCoordinator(persistenceId(), schemaContext);
 688         }
 689
 690         recoveryCoordinator.submit(currentLogRecoveryBatch, store.newWriteOnlyTransaction());
 691
 692         if(LOG.isDebugEnabled()) {
 693             LOG.debug("{} : submitted log recovery batch with size {}", persistenceId(),
 694                     currentLogRecoveryBatch.size());
 695         }
 696     }
 697
 698     @Override
 699     protected void onRecoveryComplete() {
 700         if(recoveryCoordinator != null) {
 701             Collection<DOMStoreWriteTransaction> txList = recoveryCoordinator.getTransactions();
 702
 703             if(LOG.isDebugEnabled()) {
 704                 LOG.debug("{} : recovery complete - committing {} Tx's", persistenceId(), txList.size());
 705             }
 706
 707             for(DOMStoreWriteTransaction tx: txList) {
 708                 try {
 709                     syncCommitTransaction(tx);
 710                     shardMBean.incrementCommittedTransactionCount();
 711                 } catch (InterruptedException | ExecutionException e) {
 712                     shardMBean.incrementFailedTransactionsCount();
 713                     LOG.error(e, "Failed to commit");
 714                 }
 715             }
 716         }
 717
 718         recoveryCoordinator = null;
 719         currentLogRecoveryBatch = null;
 720         updateJournalStats();
 721
 722         //notify shard manager
 723         getContext().parent().tell(new ActorInitialized(), getSelf());
 724
 725         // Being paranoid here - this method should only be called once but just in case...
 726         if(txCommitTimeoutCheckSchedule == null) {
 727             // Schedule a message to be periodically sent to check if the current in-progress
 728             // transaction should be expired and aborted.
 729             FiniteDuration period = Duration.create(transactionCommitTimeout / 3, TimeUnit.MILLISECONDS);
 730             txCommitTimeoutCheckSchedule = getContext().system().scheduler().schedule(
 731                     period, period, getSelf(),
 732                     TX_COMMIT_TIMEOUT_CHECK_MESSAGE, getContext().dispatcher(), ActorRef.noSender());
 733         }
 734     }
 735
 736     @Override
 737     protected void applyState(ActorRef clientActor, String identifier, Object data) {
 738
 739         if (data instanceof CompositeModificationPayload) {
 740             Object modification = ((CompositeModificationPayload) data).getModification();
 741
 742             if(modification == null) {
 743                 LOG.error(
 744                      "modification is null - this is very unexpected, clientActor = {}, identifier = {}",
 745                      identifier, clientActor != null ? clientActor.path().toString() : null);
 746             } else if(clientActor == null) {
 747                 // There's no clientActor to which to send a commit reply so we must be applying
 748                 // replicated state from the leader.
 749                 commitWithNewTransaction(MutableCompositeModification.fromSerializable(
 750                         modification, schemaContext));
 751             } else {
 752                 // This must be the OK to commit after replication consensus.
 753                 finishCommit(clientActor, identifier);
 754             }
 755         } else {
 756             LOG.error("Unknown state received {} Class loader = {} CompositeNodeMod.ClassLoader = {}",
 757                     data, data.getClass().getClassLoader(),
 758                     CompositeModificationPayload.class.getClassLoader());
 759         }
 760
 761         updateJournalStats();
 762
 763     }
 764
 765     private void updateJournalStats() {
 766         ReplicatedLogEntry lastLogEntry = getLastLogEntry();
 767
 768         if (lastLogEntry != null) {
 769             shardMBean.setLastLogIndex(lastLogEntry.getIndex());
 770             shardMBean.setLastLogTerm(lastLogEntry.getTerm());
 771         }
 772
 773         shardMBean.setCommitIndex(getCommitIndex());
 774         shardMBean.setLastApplied(getLastApplied());
 775     }
 776
 777     @Override
 778     protected void createSnapshot() {
 779         if (createSnapshotTransaction == null) {
 780
 781             // Create a transaction. We are really going to treat the transaction as a worker
 782             // so that this actor does not get block building the snapshot
 783             createSnapshotTransaction = createTransaction(
 784                 TransactionProxy.TransactionType.READ_ONLY.ordinal(),
 785                 "createSnapshot" + ++createSnapshotTransactionCounter, "",
 786                 CreateTransaction.CURRENT_VERSION);
 787
 788             createSnapshotTransaction.tell(
 789                 new ReadData(YangInstanceIdentifier.builder().build()).toSerializable(), self());
 790
 791         }
 792     }
 793
 794     @VisibleForTesting
 795     @Override
 796     protected void applySnapshot(ByteString snapshot) {
 797         // Since this will be done only on Recovery or when this actor is a Follower
 798         // we can safely commit everything in here. We not need to worry about event notifications
 799         // as they would have already been disabled on the follower
 800
 801         LOG.info("Applying snapshot");
 802         try {
 803             DOMStoreWriteTransaction transaction = store.newWriteOnlyTransaction();
 804             NormalizedNodeMessages.Node serializedNode = NormalizedNodeMessages.Node.parseFrom(snapshot);
 805             NormalizedNode<?, ?> node = new NormalizedNodeToNodeCodec(schemaContext)
 806                 .decode(serializedNode);
 807
 808             // delete everything first
 809             transaction.delete(YangInstanceIdentifier.builder().build());
 810
 811             // Add everything from the remote node back
 812             transaction.write(YangInstanceIdentifier.builder().build(), node);
 813             syncCommitTransaction(transaction);
 814         } catch (InvalidProtocolBufferException | InterruptedException | ExecutionException e) {
 815             LOG.error(e, "An exception occurred when applying snapshot");
 816         } finally {
 817             LOG.info("Done applying snapshot");
 818         }
 819     }
 820
 821     @Override
 822     protected void onStateChanged() {
 823         boolean isLeader = isLeader();
 824         for (ActorSelection dataChangeListener : dataChangeListeners) {
 825             dataChangeListener.tell(new EnableNotification(isLeader), getSelf());
 826         }
 827
 828         if(isLeader) {
 829             for(DelayedListenerRegistration reg: delayedListenerRegistrations) {
 830                 if(!reg.isClosed()) {
 831                     reg.setDelegate(doChangeListenerRegistration(reg.getRegisterChangeListener()));
 832                 }
 833             }
 834
 835             delayedListenerRegistrations.clear();
 836         }
 837
 838         shardMBean.setRaftState(getRaftState().name());
 839         shardMBean.setCurrentTerm(getCurrentTerm());
 840
 841         // If this actor is no longer the leader close all the transaction chains
 842         if(!isLeader){
 843             for(Map.Entry<String, DOMStoreTransactionChain> entry : transactionChains.entrySet()){
 844                 if(LOG.isDebugEnabled()) {
 845                     LOG.debug(
 846                         "onStateChanged: Closing transaction chain {} because shard {} is no longer the leader",
 847                         entry.getKey(), getId());
 848                 }
 849                 entry.getValue().close();
 850             }
 851
 852             transactionChains.clear();
 853         }
 854     }
 855
 856     @Override
 857     protected DataPersistenceProvider persistence() {
 858         return dataPersistenceProvider;
 859     }
 860
 861     @Override protected void onLeaderChanged(String oldLeader, String newLeader) {
 862         shardMBean.setLeader(newLeader);
 863     }
 864
 865     @Override public String persistenceId() {
 866         return this.name.toString();
 867     }
 868
 869     @VisibleForTesting
 870     DataPersistenceProvider getDataPersistenceProvider() {
 871         return dataPersistenceProvider;
 872     }
 873
 874     private static class ShardCreator implements Creator<Shard> {
 875
 876         private static final long serialVersionUID = 1L;
 877
 878         final ShardIdentifier name;
 879         final Map<ShardIdentifier, String> peerAddresses;
 880         final DatastoreContext datastoreContext;
 881         final SchemaContext schemaContext;
 882
 883         ShardCreator(ShardIdentifier name, Map<ShardIdentifier, String> peerAddresses,
 884                 DatastoreContext datastoreContext, SchemaContext schemaContext) {
 885             this.name = name;
 886             this.peerAddresses = peerAddresses;
 887             this.datastoreContext = datastoreContext;
 888             this.schemaContext = schemaContext;
 889         }
 890
 891         @Override
 892         public Shard create() throws Exception {
 893             return new Shard(name, peerAddresses, datastoreContext, schemaContext);
 894         }
 895     }
 896
 897     @VisibleForTesting
 898     InMemoryDOMDataStore getDataStore() {
 899         return store;
 900     }
 901
 902     @VisibleForTesting
 903     ShardStats getShardMBean() {
 904         return shardMBean;
 905     }
 906
 907     private static class DelayedListenerRegistration implements
 908         ListenerRegistration<AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>>> {
 909
 910         private volatile boolean closed;
 911
 912         private final RegisterChangeListener registerChangeListener;
 913
 914         private volatile ListenerRegistration<AsyncDataChangeListener<YangInstanceIdentifier,
 915                                                              NormalizedNode<?, ?>>> delegate;
 916
 917         DelayedListenerRegistration(RegisterChangeListener registerChangeListener) {
 918             this.registerChangeListener = registerChangeListener;
 919         }
 920
 921         void setDelegate( ListenerRegistration<AsyncDataChangeListener<YangInstanceIdentifier,
 922                                             NormalizedNode<?, ?>>> registration) {
 923             this.delegate = registration;
 924         }
 925
 926         boolean isClosed() {
 927             return closed;
 928         }
 929
 930         RegisterChangeListener getRegisterChangeListener() {
 931             return registerChangeListener;
 932         }
 933
 934         @Override
 935         public AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>> getInstance() {
 936             return delegate != null ? delegate.getInstance() : null;
 937         }
 938
 939         @Override
 940         public void close() {
 941             closed = true;
 942             if(delegate != null) {
 943                 delegate.close();
 944             }
 945         }
 946     }
 947 }