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

   1 /*
   2  * Copyright (c) 2016 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.sharding;
  10
  11 import static akka.actor.ActorRef.noSender;
  12
  13 import akka.actor.ActorRef;
  14 import akka.actor.ActorSystem;
  15 import akka.actor.PoisonPill;
  16 import akka.actor.Props;
  17 import akka.dispatch.Mapper;
  18 import akka.dispatch.OnComplete;
  19 import akka.pattern.Patterns;
  20 import akka.util.Timeout;
  21 import com.google.common.base.Optional;
  22 import com.google.common.base.Preconditions;
  23 import com.google.common.base.Throwables;
  24 import com.google.common.collect.ForwardingObject;
  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.common.util.concurrent.SettableFuture;
  29 import com.google.common.util.concurrent.Uninterruptibles;
  30 import java.util.AbstractMap.SimpleEntry;
  31 import java.util.ArrayList;
  32 import java.util.Collection;
  33 import java.util.Collections;
  34 import java.util.EnumMap;
  35 import java.util.List;
  36 import java.util.Map.Entry;
  37 import java.util.Set;
  38 import java.util.concurrent.CompletionStage;
  39 import java.util.concurrent.ExecutionException;
  40 import java.util.concurrent.TimeUnit;
  41 import java.util.concurrent.TimeoutException;
  42 import javax.annotation.Nonnull;
  43 import javax.annotation.Nullable;
  44 import javax.annotation.concurrent.GuardedBy;
  45 import org.opendaylight.controller.cluster.ActorSystemProvider;
  46 import org.opendaylight.controller.cluster.access.concepts.MemberName;
  47 import org.opendaylight.controller.cluster.databroker.actors.dds.DataStoreClient;
  48 import org.opendaylight.controller.cluster.databroker.actors.dds.SimpleDataStoreClientActor;
  49 import org.opendaylight.controller.cluster.datastore.DistributedDataStore;
  50 import org.opendaylight.controller.cluster.datastore.Shard;
  51 import org.opendaylight.controller.cluster.datastore.config.Configuration;
  52 import org.opendaylight.controller.cluster.datastore.config.ModuleShardConfiguration;
  53 import org.opendaylight.controller.cluster.datastore.messages.CreateShard;
  54 import org.opendaylight.controller.cluster.datastore.shardstrategy.ModuleShardStrategy;
  55 import org.opendaylight.controller.cluster.datastore.utils.ActorContext;
  56 import org.opendaylight.controller.cluster.datastore.utils.ClusterUtils;
  57 import org.opendaylight.controller.cluster.sharding.ShardedDataTreeActor.ShardedDataTreeActorCreator;
  58 import org.opendaylight.controller.cluster.sharding.messages.InitConfigListener;
  59 import org.opendaylight.controller.cluster.sharding.messages.LookupPrefixShard;
  60 import org.opendaylight.controller.cluster.sharding.messages.PrefixShardRemovalLookup;
  61 import org.opendaylight.controller.cluster.sharding.messages.ProducerCreated;
  62 import org.opendaylight.controller.cluster.sharding.messages.ProducerRemoved;
  63 import org.opendaylight.controller.cluster.sharding.messages.StartConfigShardLookup;
  64 import org.opendaylight.mdsal.common.api.LogicalDatastoreType;
  65 import org.opendaylight.mdsal.dom.api.DOMDataTreeCursorAwareTransaction;
  66 import org.opendaylight.mdsal.dom.api.DOMDataTreeIdentifier;
  67 import org.opendaylight.mdsal.dom.api.DOMDataTreeListener;
  68 import org.opendaylight.mdsal.dom.api.DOMDataTreeLoopException;
  69 import org.opendaylight.mdsal.dom.api.DOMDataTreeProducer;
  70 import org.opendaylight.mdsal.dom.api.DOMDataTreeProducerException;
  71 import org.opendaylight.mdsal.dom.api.DOMDataTreeService;
  72 import org.opendaylight.mdsal.dom.api.DOMDataTreeShard;
  73 import org.opendaylight.mdsal.dom.api.DOMDataTreeShardingConflictException;
  74 import org.opendaylight.mdsal.dom.api.DOMDataTreeShardingService;
  75 import org.opendaylight.mdsal.dom.broker.DOMDataTreeShardRegistration;
  76 import org.opendaylight.mdsal.dom.broker.ShardedDOMDataTree;
  77 import org.opendaylight.mdsal.dom.spi.DOMDataTreePrefixTable;
  78 import org.opendaylight.mdsal.dom.spi.DOMDataTreePrefixTableEntry;
  79 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.controller.md.sal.clustering.prefix.shard.configuration.rev170110.PrefixShards;
  80 import org.opendaylight.yangtools.concepts.ListenerRegistration;
  81 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  82 import org.slf4j.Logger;
  83 import org.slf4j.LoggerFactory;
  84 import scala.compat.java8.FutureConverters;
  85 import scala.concurrent.Await;
  86 import scala.concurrent.Future;
  87 import scala.concurrent.Promise;
  88 import scala.concurrent.duration.FiniteDuration;
  89
  90 /**
  91  * A layer on top of DOMDataTreeService that distributes producer/shard registrations to remote nodes via
  92  * {@link ShardedDataTreeActor}. Also provides QoL method for addition of prefix based clustered shard into the system.
  93  */
  94 public class DistributedShardedDOMDataTree implements DOMDataTreeService, DOMDataTreeShardingService,
  95         DistributedShardFactory {
  96
  97     private static final Logger LOG = LoggerFactory.getLogger(DistributedShardedDOMDataTree.class);
  98
  99     private static final int MAX_ACTOR_CREATION_RETRIES = 100;
 100     private static final int ACTOR_RETRY_DELAY = 100;
 101     private static final TimeUnit ACTOR_RETRY_TIME_UNIT = TimeUnit.MILLISECONDS;
 102     private static final int LOOKUP_TASK_MAX_RETRIES = 100;
 103     static final FiniteDuration SHARD_FUTURE_TIMEOUT_DURATION =
 104             new FiniteDuration(LOOKUP_TASK_MAX_RETRIES * LOOKUP_TASK_MAX_RETRIES * 3, TimeUnit.SECONDS);
 105     static final Timeout SHARD_FUTURE_TIMEOUT = new Timeout(SHARD_FUTURE_TIMEOUT_DURATION);
 106
 107     static final String ACTOR_ID = "ShardedDOMDataTreeFrontend";
 108
 109     private final ShardedDOMDataTree shardedDOMDataTree;
 110     private final ActorSystem actorSystem;
 111     private final DistributedDataStore distributedOperDatastore;
 112     private final DistributedDataStore distributedConfigDatastore;
 113
 114     private final ActorRef shardedDataTreeActor;
 115     private final MemberName memberName;
 116
 117     @GuardedBy("shards")
 118     private final DOMDataTreePrefixTable<DOMDataTreeShardRegistration<DOMDataTreeShard>> shards =
 119             DOMDataTreePrefixTable.create();
 120
 121     private final EnumMap<LogicalDatastoreType, DistributedShardRegistration> defaultShardRegistrations =
 122             new EnumMap<>(LogicalDatastoreType.class);
 123
 124     private final EnumMap<LogicalDatastoreType, Entry<DataStoreClient, ActorRef>> configurationShardMap =
 125             new EnumMap<>(LogicalDatastoreType.class);
 126
 127     private final EnumMap<LogicalDatastoreType, PrefixedShardConfigWriter> writerMap =
 128             new EnumMap<>(LogicalDatastoreType.class);
 129
 130     private final PrefixedShardConfigUpdateHandler updateHandler;
 131
 132     public DistributedShardedDOMDataTree(final ActorSystemProvider actorSystemProvider,
 133                                          final DistributedDataStore distributedOperDatastore,
 134                                          final DistributedDataStore distributedConfigDatastore) {
 135         this.actorSystem = Preconditions.checkNotNull(actorSystemProvider).getActorSystem();
 136         this.distributedOperDatastore = Preconditions.checkNotNull(distributedOperDatastore);
 137         this.distributedConfigDatastore = Preconditions.checkNotNull(distributedConfigDatastore);
 138         shardedDOMDataTree = new ShardedDOMDataTree();
 139
 140         shardedDataTreeActor = createShardedDataTreeActor(actorSystem,
 141                 new ShardedDataTreeActorCreator()
 142                         .setShardingService(this)
 143                         .setActorSystem(actorSystem)
 144                         .setClusterWrapper(distributedConfigDatastore.getActorContext().getClusterWrapper())
 145                         .setDistributedConfigDatastore(distributedConfigDatastore)
 146                         .setDistributedOperDatastore(distributedOperDatastore)
 147                         .setLookupTaskMaxRetries(LOOKUP_TASK_MAX_RETRIES),
 148                 ACTOR_ID);
 149
 150         this.memberName = distributedConfigDatastore.getActorContext().getCurrentMemberName();
 151
 152         updateHandler = new PrefixedShardConfigUpdateHandler(shardedDataTreeActor,
 153                 distributedConfigDatastore.getActorContext().getCurrentMemberName());
 154
 155         LOG.debug("{} - Starting prefix configuration shards", memberName);
 156         createPrefixConfigShard(distributedConfigDatastore);
 157         createPrefixConfigShard(distributedOperDatastore);
 158     }
 159
 160     private void createPrefixConfigShard(final DistributedDataStore dataStore) {
 161         Configuration configuration = dataStore.getActorContext().getConfiguration();
 162         Collection<MemberName> memberNames = configuration.getUniqueMemberNamesForAllShards();
 163         CreateShard createShardMessage =
 164                 new CreateShard(new ModuleShardConfiguration(PrefixShards.QNAME.getNamespace(),
 165                         "prefix-shard-configuration", ClusterUtils.PREFIX_CONFIG_SHARD_ID, ModuleShardStrategy.NAME,
 166                         memberNames),
 167                         Shard.builder(), dataStore.getActorContext().getDatastoreContext());
 168
 169         dataStore.getActorContext().getShardManager().tell(createShardMessage, noSender());
 170     }
 171
 172     /**
 173      * This will try to initialize prefix configuration shards upon their
 174      * successful start. We need to create writers to these shards, so we can
 175      * satisfy future {@link #createDistributedShard} and
 176      * {@link #resolveShardAdditions} requests and update prefix configuration
 177      * shards accordingly.
 178      *
 179      * <p>
 180      * We also need to initialize listeners on these shards, so we can react
 181      * on changes made on them by other cluster members or even by ourselves.
 182      *
 183      * <p>
 184      * Finally, we need to be sure that default shards for both operational and
 185      * configuration data stores are up and running and we have distributed
 186      * shards frontend created for them.
 187      */
 188     void init() {
 189         // create our writers to the configuration
 190         try {
 191             LOG.debug("{} - starting config shard lookup.",
 192                     distributedConfigDatastore.getActorContext().getCurrentMemberName());
 193
 194             // We have to wait for prefix config shards to be up and running
 195             // so we can create datastore clients for them
 196             handleConfigShardLookup().get(SHARD_FUTURE_TIMEOUT_DURATION.length(), SHARD_FUTURE_TIMEOUT_DURATION.unit());
 197
 198             LOG.debug("Prefix configuration shards ready - creating clients");
 199
 200         } catch (InterruptedException | ExecutionException | TimeoutException e) {
 201             throw new IllegalStateException("Prefix config shards not found", e);
 202         }
 203
 204         try {
 205             LOG.debug("Prefix configuration shards ready - creating clients");
 206             configurationShardMap.put(LogicalDatastoreType.CONFIGURATION,
 207                     createDatastoreClient(ClusterUtils.PREFIX_CONFIG_SHARD_ID,
 208                             distributedConfigDatastore.getActorContext()));
 209         } catch (final DOMDataTreeShardCreationFailedException e) {
 210             throw new IllegalStateException(
 211                     "Unable to create datastoreClient for config DS prefix configuration shard.", e);
 212         }
 213
 214         try {
 215             configurationShardMap.put(LogicalDatastoreType.OPERATIONAL,
 216                     createDatastoreClient(ClusterUtils.PREFIX_CONFIG_SHARD_ID,
 217                             distributedOperDatastore.getActorContext()));
 218
 219         } catch (final DOMDataTreeShardCreationFailedException e) {
 220             throw new IllegalStateException(
 221                         "Unable to create datastoreClient for oper DS prefix configuration shard.", e);
 222         }
 223
 224         writerMap.put(LogicalDatastoreType.CONFIGURATION, new PrefixedShardConfigWriter(
 225                 configurationShardMap.get(LogicalDatastoreType.CONFIGURATION).getKey()));
 226
 227         writerMap.put(LogicalDatastoreType.OPERATIONAL, new PrefixedShardConfigWriter(
 228                 configurationShardMap.get(LogicalDatastoreType.OPERATIONAL).getKey()));
 229
 230         updateHandler.initListener(distributedConfigDatastore, LogicalDatastoreType.CONFIGURATION);
 231         updateHandler.initListener(distributedOperDatastore, LogicalDatastoreType.OPERATIONAL);
 232
 233         distributedConfigDatastore.getActorContext().getShardManager().tell(InitConfigListener.INSTANCE, noSender());
 234         distributedOperDatastore.getActorContext().getShardManager().tell(InitConfigListener.INSTANCE, noSender());
 235
 236
 237         //create shard registration for DEFAULT_SHARD
 238         try {
 239             defaultShardRegistrations.put(LogicalDatastoreType.CONFIGURATION,
 240                     initDefaultShard(LogicalDatastoreType.CONFIGURATION));
 241         } catch (final InterruptedException | ExecutionException e) {
 242             throw new IllegalStateException("Unable to create default shard frontend for config shard", e);
 243         }
 244
 245         try {
 246             defaultShardRegistrations.put(LogicalDatastoreType.OPERATIONAL,
 247                     initDefaultShard(LogicalDatastoreType.OPERATIONAL));
 248         } catch (final InterruptedException | ExecutionException e) {
 249             throw new IllegalStateException("Unable to create default shard frontend for operational shard", e);
 250         }
 251     }
 252
 253     private ListenableFuture<List<Void>> handleConfigShardLookup() {
 254
 255         final ListenableFuture<Void> configFuture = lookupConfigShard(LogicalDatastoreType.CONFIGURATION);
 256         final ListenableFuture<Void> operFuture = lookupConfigShard(LogicalDatastoreType.OPERATIONAL);
 257
 258         return Futures.allAsList(configFuture, operFuture);
 259     }
 260
 261     private ListenableFuture<Void> lookupConfigShard(final LogicalDatastoreType type) {
 262         final SettableFuture<Void> future = SettableFuture.create();
 263
 264         final Future<Object> ask =
 265                 Patterns.ask(shardedDataTreeActor, new StartConfigShardLookup(type), SHARD_FUTURE_TIMEOUT);
 266
 267         ask.onComplete(new OnComplete<Object>() {
 268             @Override
 269             public void onComplete(final Throwable throwable, final Object result) throws Throwable {
 270                 if (throwable != null) {
 271                     future.setException(throwable);
 272                 } else {
 273                     future.set(null);
 274                 }
 275             }
 276         }, actorSystem.dispatcher());
 277
 278         return future;
 279     }
 280
 281     @Nonnull
 282     @Override
 283     public <T extends DOMDataTreeListener> ListenerRegistration<T> registerListener(
 284             final T listener, final Collection<DOMDataTreeIdentifier> subtrees,
 285             final boolean allowRxMerges, final Collection<DOMDataTreeProducer> producers)
 286             throws DOMDataTreeLoopException {
 287         return shardedDOMDataTree.registerListener(listener, subtrees, allowRxMerges, producers);
 288     }
 289
 290     @Nonnull
 291     @Override
 292     public DOMDataTreeProducer createProducer(@Nonnull final Collection<DOMDataTreeIdentifier> subtrees) {
 293         LOG.debug("{} - Creating producer for {}",
 294                 distributedConfigDatastore.getActorContext().getClusterWrapper().getCurrentMemberName(), subtrees);
 295         final DOMDataTreeProducer producer = shardedDOMDataTree.createProducer(subtrees);
 296
 297         final Object response = distributedConfigDatastore.getActorContext()
 298                 .executeOperation(shardedDataTreeActor, new ProducerCreated(subtrees));
 299         if (response == null) {
 300             LOG.debug("{} - Received success from remote nodes, creating producer:{}",
 301                     distributedConfigDatastore.getActorContext().getClusterWrapper().getCurrentMemberName(), subtrees);
 302             return new ProxyProducer(producer, subtrees, shardedDataTreeActor,
 303                     distributedConfigDatastore.getActorContext());
 304         } else if (response instanceof Exception) {
 305             closeProducer(producer);
 306             throw Throwables.propagate((Exception) response);
 307         } else {
 308             closeProducer(producer);
 309             throw new RuntimeException("Unexpected response to create producer received." + response);
 310         }
 311     }
 312
 313     @Override
 314     public CompletionStage<DistributedShardRegistration> createDistributedShard(
 315             final DOMDataTreeIdentifier prefix, final Collection<MemberName> replicaMembers)
 316             throws DOMDataTreeShardingConflictException {
 317
 318         synchronized (shards) {
 319             final DOMDataTreePrefixTableEntry<DOMDataTreeShardRegistration<DOMDataTreeShard>> lookup =
 320                     shards.lookup(prefix);
 321             if (lookup != null && lookup.getValue().getPrefix().equals(prefix)) {
 322                 throw new DOMDataTreeShardingConflictException(
 323                         "Prefix " + prefix + " is already occupied by another shard.");
 324             }
 325         }
 326
 327         final PrefixedShardConfigWriter writer = writerMap.get(prefix.getDatastoreType());
 328
 329         final ListenableFuture<Void> writeFuture =
 330                 writer.writeConfig(prefix.getRootIdentifier(), replicaMembers);
 331
 332         final Promise<DistributedShardRegistration> shardRegistrationPromise = akka.dispatch.Futures.promise();
 333         Futures.addCallback(writeFuture, new FutureCallback<Void>() {
 334             @Override
 335             public void onSuccess(@Nullable final Void result) {
 336
 337                 final Future<Object> ask =
 338                         Patterns.ask(shardedDataTreeActor, new LookupPrefixShard(prefix), SHARD_FUTURE_TIMEOUT);
 339
 340                 shardRegistrationPromise.completeWith(ask.transform(
 341                         new Mapper<Object, DistributedShardRegistration>() {
 342                             @Override
 343                             public DistributedShardRegistration apply(final Object parameter) {
 344                                 return new DistributedShardRegistrationImpl(
 345                                         prefix, shardedDataTreeActor, DistributedShardedDOMDataTree.this);
 346                             }
 347                         },
 348                         new Mapper<Throwable, Throwable>() {
 349                             @Override
 350                             public Throwable apply(final Throwable throwable) {
 351                                 return new DOMDataTreeShardCreationFailedException(
 352                                         "Unable to create a cds shard.", throwable);
 353                             }
 354                         }, actorSystem.dispatcher()));
 355             }
 356
 357             @Override
 358             public void onFailure(final Throwable throwable) {
 359                 shardRegistrationPromise.failure(
 360                         new DOMDataTreeShardCreationFailedException("Unable to create a cds shard.", throwable));
 361             }
 362         });
 363
 364         return FutureConverters.toJava(shardRegistrationPromise.future());
 365     }
 366
 367     void resolveShardAdditions(final Set<DOMDataTreeIdentifier> additions) {
 368         LOG.debug("Member {}: Resolving additions : {}", memberName, additions);
 369         final ArrayList<DOMDataTreeIdentifier> list = new ArrayList<>(additions);
 370         // we need to register the shards from top to bottom, so we need to atleast make sure the ordering reflects that
 371         Collections.sort(list, (o1, o2) -> {
 372             if (o1.getRootIdentifier().getPathArguments().size() < o2.getRootIdentifier().getPathArguments().size()) {
 373                 return -1;
 374             } else if (o1.getRootIdentifier().getPathArguments().size()
 375                     == o2.getRootIdentifier().getPathArguments().size()) {
 376                 return 0;
 377             } else {
 378                 return 1;
 379             }
 380         });
 381         list.forEach(this::createShardFrontend);
 382     }
 383
 384     void resolveShardRemovals(final Set<DOMDataTreeIdentifier> removals) {
 385         LOG.debug("Member {}: Resolving removals : {}", memberName, removals);
 386
 387         // do we need to go from bottom to top?
 388         removals.forEach(this::despawnShardFrontend);
 389     }
 390
 391     private void createShardFrontend(final DOMDataTreeIdentifier prefix) {
 392         LOG.debug("Member {}: Creating CDS shard for prefix: {}", memberName, prefix);
 393         final String shardName = ClusterUtils.getCleanShardName(prefix.getRootIdentifier());
 394         final DistributedDataStore distributedDataStore =
 395                 prefix.getDatastoreType().equals(org.opendaylight.mdsal.common.api.LogicalDatastoreType.CONFIGURATION)
 396                         ? distributedConfigDatastore : distributedOperDatastore;
 397
 398         try (final DOMDataTreeProducer producer = localCreateProducer(Collections.singletonList(prefix))) {
 399             final Entry<DataStoreClient, ActorRef> entry =
 400                     createDatastoreClient(shardName, distributedDataStore.getActorContext());
 401
 402             final DistributedShardFrontend shard =
 403                     new DistributedShardFrontend(distributedDataStore, entry.getKey(), prefix);
 404
 405             @SuppressWarnings("unchecked")
 406             final DOMDataTreeShardRegistration<DOMDataTreeShard> reg =
 407                     (DOMDataTreeShardRegistration) shardedDOMDataTree.registerDataTreeShard(prefix, shard, producer);
 408
 409             synchronized (shards) {
 410                 shards.store(prefix, reg);
 411             }
 412
 413         } catch (final DOMDataTreeShardingConflictException e) {
 414             LOG.error("{}: Prefix {} is already occupied by another shard",
 415                     distributedConfigDatastore.getActorContext().getClusterWrapper().getCurrentMemberName(), prefix, e);
 416         } catch (DOMDataTreeProducerException e) {
 417             LOG.error("Unable to close producer", e);
 418         } catch (DOMDataTreeShardCreationFailedException e) {
 419             LOG.error("Unable to create datastore client for shard {}", prefix, e);
 420         }
 421     }
 422
 423     private void despawnShardFrontend(final DOMDataTreeIdentifier prefix) {
 424         LOG.debug("Member {}: Removing CDS shard for prefix: {}", memberName, prefix);
 425         final DOMDataTreePrefixTableEntry<DOMDataTreeShardRegistration<DOMDataTreeShard>> lookup;
 426         synchronized (shards) {
 427             lookup = shards.lookup(prefix);
 428         }
 429
 430         if (lookup == null || !lookup.getValue().getPrefix().equals(prefix)) {
 431             LOG.debug("Member {}: Received despawn for non-existing CDS shard frontend, prefix: {}, ignoring..",
 432                     memberName, prefix);
 433             return;
 434         }
 435
 436         lookup.getValue().close();
 437         // need to remove from our local table thats used for tracking
 438         synchronized (shards) {
 439             shards.remove(prefix);
 440         }
 441
 442         final PrefixedShardConfigWriter writer = writerMap.get(prefix.getDatastoreType());
 443         final ListenableFuture<Void> future = writer.removeConfig(prefix.getRootIdentifier());
 444
 445         Futures.addCallback(future, new FutureCallback<Void>() {
 446             @Override
 447             public void onSuccess(@Nullable Void result) {
 448                 LOG.debug("{} - Succesfuly removed shard for {}", memberName, prefix);
 449             }
 450
 451             @Override
 452             public void onFailure(Throwable throwable) {
 453                 LOG.error("Removal of shard {} from configuration failed.", prefix, throwable);
 454             }
 455         });
 456     }
 457
 458     DOMDataTreePrefixTableEntry<DOMDataTreeShardRegistration<DOMDataTreeShard>> lookupShardFrontend(
 459             final DOMDataTreeIdentifier prefix) {
 460         return shards.lookup(prefix);
 461
 462     }
 463
 464     DOMDataTreeProducer localCreateProducer(final Collection<DOMDataTreeIdentifier> prefix) {
 465         return shardedDOMDataTree.createProducer(prefix);
 466     }
 467
 468     @Nonnull
 469     @Override
 470     public <T extends DOMDataTreeShard> ListenerRegistration<T> registerDataTreeShard(
 471             @Nonnull final DOMDataTreeIdentifier prefix,
 472             @Nonnull final T shard,
 473             @Nonnull final DOMDataTreeProducer producer)
 474             throws DOMDataTreeShardingConflictException {
 475
 476         LOG.debug("Registering shard[{}] at prefix: {}", shard, prefix);
 477
 478         if (producer instanceof ProxyProducer) {
 479             return shardedDOMDataTree.registerDataTreeShard(prefix, shard, ((ProxyProducer) producer).delegate());
 480         }
 481
 482         return shardedDOMDataTree.registerDataTreeShard(prefix, shard, producer);
 483     }
 484
 485     @SuppressWarnings("checkstyle:IllegalCatch")
 486     private Entry<DataStoreClient, ActorRef> createDatastoreClient(
 487             final String shardName, final ActorContext actorContext)
 488             throws DOMDataTreeShardCreationFailedException {
 489
 490         LOG.debug("Creating distributed datastore client for shard {}", shardName);
 491         final Props distributedDataStoreClientProps =
 492                 SimpleDataStoreClientActor.props(memberName, "Shard-" + shardName, actorContext, shardName);
 493
 494         final ActorRef clientActor = actorSystem.actorOf(distributedDataStoreClientProps);
 495         try {
 496             return new SimpleEntry<>(SimpleDataStoreClientActor
 497                     .getDistributedDataStoreClient(clientActor, 30, TimeUnit.SECONDS), clientActor);
 498         } catch (final Exception e) {
 499             LOG.error("Failed to get actor for {}", distributedDataStoreClientProps, e);
 500             clientActor.tell(PoisonPill.getInstance(), noSender());
 501             throw new DOMDataTreeShardCreationFailedException(
 502                     "Unable to create datastore client for shard{" + shardName + "}", e);
 503         }
 504     }
 505
 506     @SuppressWarnings("checkstyle:IllegalCatch")
 507     private DistributedShardRegistration initDefaultShard(final LogicalDatastoreType logicalDatastoreType)
 508             throws ExecutionException, InterruptedException {
 509         final Collection<MemberName> names =
 510                 distributedConfigDatastore.getActorContext().getConfiguration().getUniqueMemberNamesForAllShards();
 511
 512         final PrefixedShardConfigWriter writer = writerMap.get(logicalDatastoreType);
 513
 514         if (writer.checkDefaultIsPresent()) {
 515             LOG.debug("Default shard for {} is already present in the config. Possibly saved in snapshot.",
 516                     logicalDatastoreType);
 517             return new DistributedShardRegistrationImpl(
 518                     new DOMDataTreeIdentifier(logicalDatastoreType, YangInstanceIdentifier.EMPTY),
 519                     shardedDataTreeActor, this);
 520         } else {
 521             try {
 522                 // There can be situation when there is already started default shard
 523                 // because it is present in modules.conf. In that case we have to create
 524                 // just frontend for default shard, but not shard itself
 525                 // TODO we don't have to do it for config and operational default shard
 526                 // separately. Just one of them should be enough
 527                 final ActorContext actorContext = logicalDatastoreType == LogicalDatastoreType.CONFIGURATION
 528                         ? distributedConfigDatastore.getActorContext() : distributedOperDatastore.getActorContext();
 529
 530                 final Optional<ActorRef> defaultLocalShardOptional =
 531                         actorContext.findLocalShard(ClusterUtils.getCleanShardName(YangInstanceIdentifier.EMPTY));
 532
 533                 if (defaultLocalShardOptional.isPresent()) {
 534                     LOG.debug("{} Default shard is already started, creating just frontend", logicalDatastoreType);
 535                     createShardFrontend(new DOMDataTreeIdentifier(logicalDatastoreType, YangInstanceIdentifier.EMPTY));
 536                     return new DistributedShardRegistrationImpl(
 537                             new DOMDataTreeIdentifier(logicalDatastoreType, YangInstanceIdentifier.EMPTY),
 538                             shardedDataTreeActor, this);
 539                 }
 540
 541                 // we should probably only have one node create the default shards
 542                 return Await.result(FutureConverters.toScala(createDistributedShard(
 543                         new DOMDataTreeIdentifier(logicalDatastoreType, YangInstanceIdentifier.EMPTY), names)),
 544                         SHARD_FUTURE_TIMEOUT_DURATION);
 545             } catch (DOMDataTreeShardingConflictException e) {
 546                 LOG.debug("Default shard already registered, possibly due to other node doing it faster");
 547                 return new DistributedShardRegistrationImpl(
 548                         new DOMDataTreeIdentifier(logicalDatastoreType, YangInstanceIdentifier.EMPTY),
 549                         shardedDataTreeActor, this);
 550             } catch (Exception e) {
 551                 LOG.error("{} default shard initialization failed", logicalDatastoreType, e);
 552                 throw new RuntimeException(e);
 553             }
 554         }
 555     }
 556
 557     private static void closeProducer(final DOMDataTreeProducer producer) {
 558         try {
 559             producer.close();
 560         } catch (final DOMDataTreeProducerException e) {
 561             LOG.error("Unable to close producer", e);
 562         }
 563     }
 564
 565     @SuppressWarnings("checkstyle:IllegalCatch")
 566     private static ActorRef createShardedDataTreeActor(final ActorSystem actorSystem,
 567                                                        final ShardedDataTreeActorCreator creator,
 568                                                        final String shardDataTreeActorId) {
 569         Exception lastException = null;
 570
 571         for (int i = 0; i < MAX_ACTOR_CREATION_RETRIES; i++) {
 572             try {
 573                 return actorSystem.actorOf(creator.props(), shardDataTreeActorId);
 574             } catch (final Exception e) {
 575                 lastException = e;
 576                 Uninterruptibles.sleepUninterruptibly(ACTOR_RETRY_DELAY, ACTOR_RETRY_TIME_UNIT);
 577                 LOG.debug("Could not create actor {} because of {} -"
 578                                 + " waiting for sometime before retrying (retry count = {})",
 579                         shardDataTreeActorId, e.getMessage(), i);
 580             }
 581         }
 582
 583         throw new IllegalStateException("Failed to create actor for ShardedDOMDataTree", lastException);
 584     }
 585
 586     private class DistributedShardRegistrationImpl implements DistributedShardRegistration {
 587
 588         private final DOMDataTreeIdentifier prefix;
 589         private final ActorRef shardedDataTreeActor;
 590         private final DistributedShardedDOMDataTree distributedShardedDOMDataTree;
 591
 592         DistributedShardRegistrationImpl(final DOMDataTreeIdentifier prefix,
 593                                          final ActorRef shardedDataTreeActor,
 594                                          final DistributedShardedDOMDataTree distributedShardedDOMDataTree) {
 595             this.prefix = prefix;
 596             this.shardedDataTreeActor = shardedDataTreeActor;
 597             this.distributedShardedDOMDataTree = distributedShardedDOMDataTree;
 598         }
 599
 600         @Override
 601         public CompletionStage<Void> close() {
 602             // first despawn on the local node
 603             distributedShardedDOMDataTree.despawnShardFrontend(prefix);
 604             // update the config so the remote nodes are updated
 605             final Future<Object> ask =
 606                     Patterns.ask(shardedDataTreeActor, new PrefixShardRemovalLookup(prefix), SHARD_FUTURE_TIMEOUT);
 607
 608             final Future<Void> closeFuture = ask.transform(
 609                     new Mapper<Object, Void>() {
 610                         @Override
 611                         public Void apply(Object parameter) {
 612                             return null;
 613                         }
 614                     },
 615                     new Mapper<Throwable, Throwable>() {
 616                         @Override
 617                         public Throwable apply(Throwable throwable) {
 618                             return throwable;
 619                         }
 620                     }, actorSystem.dispatcher());
 621
 622             return FutureConverters.toJava(closeFuture);
 623         }
 624     }
 625
 626     private static final class ProxyProducer extends ForwardingObject implements DOMDataTreeProducer {
 627
 628         private final DOMDataTreeProducer delegate;
 629         private final Collection<DOMDataTreeIdentifier> subtrees;
 630         private final ActorRef shardDataTreeActor;
 631         private final ActorContext actorContext;
 632
 633         ProxyProducer(final DOMDataTreeProducer delegate,
 634                       final Collection<DOMDataTreeIdentifier> subtrees,
 635                       final ActorRef shardDataTreeActor,
 636                       final ActorContext actorContext) {
 637             this.delegate = Preconditions.checkNotNull(delegate);
 638             this.subtrees = Preconditions.checkNotNull(subtrees);
 639             this.shardDataTreeActor = Preconditions.checkNotNull(shardDataTreeActor);
 640             this.actorContext = Preconditions.checkNotNull(actorContext);
 641         }
 642
 643         @Nonnull
 644         @Override
 645         public DOMDataTreeCursorAwareTransaction createTransaction(final boolean isolated) {
 646             return delegate.createTransaction(isolated);
 647         }
 648
 649         @Nonnull
 650         @Override
 651         public DOMDataTreeProducer createProducer(@Nonnull final Collection<DOMDataTreeIdentifier> subtrees) {
 652             // TODO we probably don't need to distribute this on the remote nodes since once we have this producer
 653             // open we surely have the rights to all the subtrees.
 654             return delegate.createProducer(subtrees);
 655         }
 656
 657         @Override
 658         public void close() throws DOMDataTreeProducerException {
 659             delegate.close();
 660
 661             final Object o = actorContext.executeOperation(shardDataTreeActor, new ProducerRemoved(subtrees));
 662             if (o instanceof DOMDataTreeProducerException) {
 663                 throw ((DOMDataTreeProducerException) o);
 664             } else if (o instanceof Throwable) {
 665                 throw new DOMDataTreeProducerException("Unable to close producer", (Throwable) o);
 666             }
 667         }
 668
 669         @Override
 670         protected DOMDataTreeProducer delegate() {
 671             return delegate;
 672         }
 673     }
 674 }