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

   1 /*
   2  * Copyright (c) 2015 Brocade Communications 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 package org.opendaylight.controller.cluster.datastore.entityownership;
   9
  10 import static org.opendaylight.controller.cluster.datastore.entityownership.EntityOwnersModel.CANDIDATE_NAME_NODE_ID;
  11 import static org.opendaylight.controller.cluster.datastore.entityownership.EntityOwnersModel.CANDIDATE_NODE_ID;
  12 import static org.opendaylight.controller.cluster.datastore.entityownership.EntityOwnersModel.ENTITY_ID_NODE_ID;
  13 import static org.opendaylight.controller.cluster.datastore.entityownership.EntityOwnersModel.ENTITY_ID_QNAME;
  14 import static org.opendaylight.controller.cluster.datastore.entityownership.EntityOwnersModel.ENTITY_NODE_ID;
  15 import static org.opendaylight.controller.cluster.datastore.entityownership.EntityOwnersModel.ENTITY_OWNERS_PATH;
  16 import static org.opendaylight.controller.cluster.datastore.entityownership.EntityOwnersModel.ENTITY_OWNER_NODE_ID;
  17 import static org.opendaylight.controller.cluster.datastore.entityownership.EntityOwnersModel.ENTITY_OWNER_QNAME;
  18 import static org.opendaylight.controller.cluster.datastore.entityownership.EntityOwnersModel.ENTITY_TYPES_PATH;
  19 import static org.opendaylight.controller.cluster.datastore.entityownership.EntityOwnersModel.ENTITY_TYPE_NODE_ID;
  20 import static org.opendaylight.controller.cluster.datastore.entityownership.EntityOwnersModel.ENTITY_TYPE_QNAME;
  21 import static org.opendaylight.controller.cluster.datastore.entityownership.EntityOwnersModel.candidateMapEntry;
  22 import static org.opendaylight.controller.cluster.datastore.entityownership.EntityOwnersModel.candidateNodeKey;
  23 import static org.opendaylight.controller.cluster.datastore.entityownership.EntityOwnersModel.candidatePath;
  24 import static org.opendaylight.controller.cluster.datastore.entityownership.EntityOwnersModel.createEntity;
  25 import static org.opendaylight.controller.cluster.datastore.entityownership.EntityOwnersModel.entityOwnersWithCandidate;
  26 import akka.actor.ActorRef;
  27 import akka.actor.ActorSelection;
  28 import akka.actor.Props;
  29 import akka.pattern.Patterns;
  30 import com.google.common.base.Optional;
  31 import com.google.common.base.Strings;
  32 import java.util.ArrayList;
  33 import java.util.Collection;
  34 import java.util.HashMap;
  35 import java.util.HashSet;
  36 import java.util.Map;
  37 import java.util.Set;
  38 import java.util.concurrent.TimeUnit;
  39 import org.opendaylight.controller.cluster.datastore.DatastoreContext;
  40 import org.opendaylight.controller.cluster.datastore.Shard;
  41 import org.opendaylight.controller.cluster.datastore.entityownership.messages.CandidateAdded;
  42 import org.opendaylight.controller.cluster.datastore.entityownership.messages.CandidateRemoved;
  43 import org.opendaylight.controller.cluster.datastore.entityownership.messages.RegisterCandidateLocal;
  44 import org.opendaylight.controller.cluster.datastore.entityownership.messages.RegisterListenerLocal;
  45 import org.opendaylight.controller.cluster.datastore.entityownership.messages.UnregisterCandidateLocal;
  46 import org.opendaylight.controller.cluster.datastore.entityownership.messages.UnregisterListenerLocal;
  47 import org.opendaylight.controller.cluster.datastore.identifiers.ShardIdentifier;
  48 import org.opendaylight.controller.cluster.datastore.messages.BatchedModifications;
  49 import org.opendaylight.controller.cluster.datastore.messages.PeerDown;
  50 import org.opendaylight.controller.cluster.datastore.messages.PeerUp;
  51 import org.opendaylight.controller.cluster.datastore.messages.SuccessReply;
  52 import org.opendaylight.controller.cluster.datastore.modification.DeleteModification;
  53 import org.opendaylight.controller.cluster.datastore.modification.MergeModification;
  54 import org.opendaylight.controller.cluster.datastore.modification.WriteModification;
  55 import org.opendaylight.controller.md.sal.common.api.clustering.Entity;
  56 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  57 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
  58 import org.opendaylight.yangtools.yang.data.api.schema.DataContainerChild;
  59 import org.opendaylight.yangtools.yang.data.api.schema.MapEntryNode;
  60 import org.opendaylight.yangtools.yang.data.api.schema.MapNode;
  61 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  62 import org.opendaylight.yangtools.yang.data.impl.schema.ImmutableNodes;
  63 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  64 import scala.concurrent.Future;
  65
  66 /**
  67  * Special Shard for EntityOwnership.
  68  *
  69  * @author Thomas Pantelis
  70  */
  71 class EntityOwnershipShard extends Shard {
  72     private final String localMemberName;
  73     private final EntityOwnershipShardCommitCoordinator commitCoordinator;
  74     private final EntityOwnershipListenerSupport listenerSupport;
  75     private final Set<String> downPeerMemberNames = new HashSet<>();
  76     private final Map<String, String> peerIdToMemberNames = new HashMap<>();
  77
  78     private static DatastoreContext noPersistenceDatastoreContext(DatastoreContext datastoreContext) {
  79         return DatastoreContext.newBuilderFrom(datastoreContext).persistent(false).build();
  80     }
  81
  82     protected EntityOwnershipShard(ShardIdentifier name, Map<String, String> peerAddresses,
  83             DatastoreContext datastoreContext, SchemaContext schemaContext, String localMemberName) {
  84         super(name, peerAddresses, noPersistenceDatastoreContext(datastoreContext), schemaContext);
  85         this.localMemberName = localMemberName;
  86         this.commitCoordinator = new EntityOwnershipShardCommitCoordinator(localMemberName, LOG);
  87         this.listenerSupport = new EntityOwnershipListenerSupport(getContext(), persistenceId());
  88
  89         for(String peerId: peerAddresses.keySet()) {
  90             ShardIdentifier shardId = ShardIdentifier.builder().fromShardIdString(peerId).build();
  91             peerIdToMemberNames.put(peerId, shardId.getMemberName());
  92         }
  93     }
  94
  95     @Override
  96     protected void onDatastoreContext(DatastoreContext context) {
  97         super.onDatastoreContext(noPersistenceDatastoreContext(context));
  98     }
  99
 100     @Override
 101     protected void onRecoveryComplete() {
 102         super.onRecoveryComplete();
 103
 104         new CandidateListChangeListener(getSelf(), persistenceId()).init(getDataStore());
 105         new EntityOwnerChangeListener(localMemberName, listenerSupport).init(getDataStore());
 106     }
 107
 108     @Override
 109     public void onReceiveCommand(final Object message) throws Exception {
 110         if(message instanceof RegisterCandidateLocal) {
 111             onRegisterCandidateLocal((RegisterCandidateLocal)message);
 112         } else if(message instanceof UnregisterCandidateLocal) {
 113             onUnregisterCandidateLocal((UnregisterCandidateLocal)message);
 114         } else if(message instanceof CandidateAdded){
 115             onCandidateAdded((CandidateAdded) message);
 116         } else if(message instanceof CandidateRemoved){
 117             onCandidateRemoved((CandidateRemoved) message);
 118         } else if(message instanceof PeerDown) {
 119             onPeerDown((PeerDown) message);
 120         } else if(message instanceof PeerUp) {
 121             onPeerUp((PeerUp) message);
 122         } if(message instanceof RegisterListenerLocal) {
 123             onRegisterListenerLocal((RegisterListenerLocal)message);
 124         } if(message instanceof UnregisterListenerLocal) {
 125             onUnregisterListenerLocal((UnregisterListenerLocal)message);
 126         } else if(!commitCoordinator.handleMessage(message, this)) {
 127             super.onReceiveCommand(message);
 128         }
 129     }
 130
 131     private void onRegisterCandidateLocal(RegisterCandidateLocal registerCandidate) {
 132         LOG.debug("{}: onRegisterCandidateLocal: {}", persistenceId(), registerCandidate);
 133
 134         listenerSupport.setHasCandidateForEntity(registerCandidate.getEntity());
 135
 136         NormalizedNode<?, ?> entityOwners = entityOwnersWithCandidate(registerCandidate.getEntity().getType(),
 137                 registerCandidate.getEntity().getId(), localMemberName);
 138         commitCoordinator.commitModification(new MergeModification(ENTITY_OWNERS_PATH, entityOwners), this);
 139
 140         getSender().tell(SuccessReply.INSTANCE, getSelf());
 141     }
 142
 143     private void onUnregisterCandidateLocal(UnregisterCandidateLocal unregisterCandidate) {
 144         LOG.debug("{}: onUnregisterCandidateLocal: {}", persistenceId(), unregisterCandidate);
 145
 146         Entity entity = unregisterCandidate.getEntity();
 147         listenerSupport.unsetHasCandidateForEntity(entity);
 148
 149         YangInstanceIdentifier candidatePath = candidatePath(entity.getType(), entity.getId(), localMemberName);
 150         commitCoordinator.commitModification(new DeleteModification(candidatePath), this);
 151
 152         getSender().tell(SuccessReply.INSTANCE, getSelf());
 153     }
 154
 155     private void onRegisterListenerLocal(final RegisterListenerLocal registerListener) {
 156         LOG.debug("{}: onRegisterListenerLocal: {}", persistenceId(), registerListener);
 157
 158         listenerSupport.addEntityOwnershipListener(registerListener.getEntityType(), registerListener.getListener());
 159
 160         getSender().tell(SuccessReply.INSTANCE, getSelf());
 161
 162         searchForEntitiesOwnedBy(localMemberName, new EntityWalker() {
 163             @Override
 164             public void onEntity(MapEntryNode entityTypeNode, MapEntryNode entityNode) {
 165                 Optional<DataContainerChild<? extends PathArgument, ?>> possibleType =
 166                         entityTypeNode.getChild(ENTITY_TYPE_NODE_ID);
 167                 String entityType = possibleType.isPresent() ? possibleType.get().getValue().toString() : null;
 168                 if(registerListener.getEntityType().equals(entityType)) {
 169                     Entity entity = new Entity(entityType,
 170                             (YangInstanceIdentifier) entityNode.getChild(ENTITY_ID_NODE_ID).get().getValue());
 171                     listenerSupport.notifyEntityOwnershipListener(entity, false, true, true, registerListener.getListener());
 172                 }
 173             }
 174         });
 175     }
 176
 177     private void onUnregisterListenerLocal(UnregisterListenerLocal unregisterListener) {
 178         LOG.debug("{}: onUnregisterListenerLocal: {}", persistenceId(), unregisterListener);
 179
 180         listenerSupport.removeEntityOwnershipListener(unregisterListener.getEntityType(), unregisterListener.getListener());
 181
 182         getSender().tell(SuccessReply.INSTANCE, getSelf());
 183     }
 184
 185     void tryCommitModifications(final BatchedModifications modifications) {
 186         if(isLeader()) {
 187             LOG.debug("{}: Committing BatchedModifications {} locally", persistenceId(), modifications.getTransactionID());
 188
 189             // Note that it's possible the commit won't get consensus and will timeout and not be applied
 190             // to the state. However we don't need to retry it in that case b/c it will be committed to
 191             // the journal first and, once a majority of followers come back on line and it is replicated,
 192             // it will be applied at that point.
 193             handleBatchedModificationsLocal(modifications, self());
 194         } else {
 195             final ActorSelection leader = getLeader();
 196             if (leader != null) {
 197                 if(LOG.isDebugEnabled()) {
 198                     LOG.debug("{}: Sending BatchedModifications {} to leader {}", persistenceId(),
 199                             modifications.getTransactionID(), leader);
 200                 }
 201
 202                 Future<Object> future = Patterns.ask(leader, modifications, TimeUnit.SECONDS.toMillis(
 203                         getDatastoreContext().getShardTransactionCommitTimeoutInSeconds()));
 204
 205                 Patterns.pipe(future, getContext().dispatcher()).pipeTo(getSelf(), ActorRef.noSender());
 206             }
 207         }
 208     }
 209
 210     boolean hasLeader() {
 211         return getLeader() != null && !isIsolatedLeader();
 212     }
 213
 214     @Override
 215     protected void onStateChanged() {
 216         super.onStateChanged();
 217
 218         commitCoordinator.onStateChanged(this, isLeader());
 219     }
 220
 221     @Override
 222     protected void onLeaderChanged(String oldLeader, String newLeader) {
 223         super.onLeaderChanged(oldLeader, newLeader);
 224
 225         LOG.debug("{}: onLeaderChanged: oldLeader: {}, newLeader: {}, isLeader: {}", persistenceId(), oldLeader,
 226                 newLeader, isLeader());
 227
 228         if(isLeader()) {
 229             // We were just elected leader. If the old leader is down, select new owners for the entities
 230             // owned by the down leader.
 231
 232             String oldLeaderMemberName = peerIdToMemberNames.get(oldLeader);
 233
 234             LOG.debug("{}: oldLeaderMemberName: {}", persistenceId(), oldLeaderMemberName);
 235
 236             if(downPeerMemberNames.contains(oldLeaderMemberName)) {
 237                 selectNewOwnerForEntitiesOwnedBy(oldLeaderMemberName);
 238             }
 239         }
 240     }
 241
 242     private void onCandidateRemoved(CandidateRemoved message) {
 243         LOG.debug("{}: onCandidateRemoved: {}", persistenceId(), message);
 244
 245         if(isLeader()) {
 246             String currentOwner = getCurrentOwner(message.getEntityPath());
 247             if(message.getRemovedCandidate().equals(currentOwner)){
 248                 writeNewOwner(message.getEntityPath(), newOwner(message.getRemainingCandidates()));
 249             }
 250         } else {
 251             // We're not the leader. If the removed candidate is our local member then check if we actually
 252             // have a local candidate registered. If we do then we must have been partitioned from the leader
 253             // and the leader removed our candidate since the leader can't tell the difference between a
 254             // temporary network partition and a node's process actually restarted. So, in that case, re-add
 255             // our candidate.
 256             if(localMemberName.equals(message.getRemovedCandidate()) &&
 257                     listenerSupport.hasCandidateForEntity(createEntity(message.getEntityPath()))) {
 258                 LOG.debug("Local candidate member was removed but a local candidate is registered for {}" +
 259                     " - adding back local candidate", message.getEntityPath());
 260
 261                 commitCoordinator.commitModification(new MergeModification(
 262                         candidatePath(message.getEntityPath(), localMemberName),
 263                         candidateMapEntry(localMemberName)), this);
 264             }
 265         }
 266     }
 267
 268     private void onCandidateAdded(CandidateAdded message) {
 269         if(!isLeader()){
 270             return;
 271         }
 272
 273         LOG.debug("{}: onCandidateAdded: {}", persistenceId(), message);
 274
 275         // Since a node's candidate member is only added by the node itself, we can assume the node is up so
 276         // remove it from the downPeerMemberNames.
 277         downPeerMemberNames.remove(message.getNewCandidate());
 278
 279         String currentOwner = getCurrentOwner(message.getEntityPath());
 280         if(Strings.isNullOrEmpty(currentOwner)){
 281             writeNewOwner(message.getEntityPath(), newOwner(message.getAllCandidates()));
 282         }
 283     }
 284
 285     private void onPeerDown(PeerDown peerDown) {
 286         LOG.info("{}: onPeerDown: {}", persistenceId(), peerDown);
 287
 288         String downMemberName = peerDown.getMemberName();
 289         if(downPeerMemberNames.add(downMemberName) && isLeader()) {
 290             // Remove the down peer as a candidate from all entities.
 291             removeCandidateFromEntities(downMemberName);
 292         }
 293     }
 294
 295     private void onPeerUp(PeerUp peerUp) {
 296         LOG.debug("{}: onPeerUp: {}", persistenceId(), peerUp);
 297
 298         peerIdToMemberNames.put(peerUp.getPeerId(), peerUp.getMemberName());
 299         downPeerMemberNames.remove(peerUp.getMemberName());
 300     }
 301
 302     private void selectNewOwnerForEntitiesOwnedBy(String owner) {
 303         final BatchedModifications modifications = commitCoordinator.newBatchedModifications();
 304         searchForEntitiesOwnedBy(owner, new EntityWalker() {
 305             @Override
 306             public void onEntity(MapEntryNode entityTypeNode, MapEntryNode entityNode) {
 307                 Object newOwner = newOwner(getCandidateNames(entityNode));
 308                 YangInstanceIdentifier entityPath = YangInstanceIdentifier.builder(ENTITY_TYPES_PATH).
 309                         node(entityTypeNode.getIdentifier()).node(ENTITY_NODE_ID).node(entityNode.getIdentifier()).
 310                         node(ENTITY_OWNER_NODE_ID).build();
 311
 312                 LOG.debug("{}: Found entity {}, writing new owner {}", persistenceId(), entityPath, newOwner);
 313
 314                 modifications.addModification(new WriteModification(entityPath,
 315                         ImmutableNodes.leafNode(ENTITY_OWNER_NODE_ID, newOwner)));
 316             }
 317         });
 318
 319         commitCoordinator.commitModifications(modifications, this);
 320     }
 321
 322     private void removeCandidateFromEntities(final String owner) {
 323         final BatchedModifications modifications = commitCoordinator.newBatchedModifications();
 324         searchForEntities(new EntityWalker() {
 325             @Override
 326             public void onEntity(MapEntryNode entityTypeNode, MapEntryNode entityNode) {
 327                 if(hasCandidate(entityNode, owner)) {
 328                     YangInstanceIdentifier entityId =
 329                             (YangInstanceIdentifier)entityNode.getIdentifier().getKeyValues().get(ENTITY_ID_QNAME);
 330                     YangInstanceIdentifier candidatePath = candidatePath(
 331                             entityTypeNode.getIdentifier().getKeyValues().get(ENTITY_TYPE_QNAME).toString(),
 332                             entityId, owner);
 333
 334                     LOG.info("{}: Found entity {}, removing candidate {}, path {}", persistenceId(), entityId,
 335                             owner, candidatePath);
 336
 337                     modifications.addModification(new DeleteModification(candidatePath));
 338                 }
 339             }
 340         });
 341
 342         commitCoordinator.commitModifications(modifications, this);
 343     }
 344
 345     private static boolean hasCandidate(MapEntryNode entity, String candidateName) {
 346         return ((MapNode)entity.getChild(CANDIDATE_NODE_ID).get()).getChild(candidateNodeKey(candidateName)).isPresent();
 347     }
 348
 349     private void searchForEntitiesOwnedBy(final String owner, final EntityWalker walker) {
 350         Optional<NormalizedNode<?, ?>> possibleEntityTypes = getDataStore().readNode(ENTITY_TYPES_PATH);
 351         if(!possibleEntityTypes.isPresent()) {
 352             return;
 353         }
 354
 355         LOG.debug("{}: Searching for entities owned by {}", persistenceId(), owner);
 356
 357         searchForEntities(new EntityWalker() {
 358             @Override
 359             public void onEntity(MapEntryNode entityTypeNode, MapEntryNode entityNode) {
 360                 Optional<DataContainerChild<? extends PathArgument, ?>> possibleOwner =
 361                         entityNode.getChild(ENTITY_OWNER_NODE_ID);
 362                 if(possibleOwner.isPresent() && owner.equals(possibleOwner.get().getValue().toString())) {
 363                     walker.onEntity(entityTypeNode, entityNode);
 364                 }
 365             }
 366         });
 367     }
 368
 369     private void searchForEntities(EntityWalker walker) {
 370         Optional<NormalizedNode<?, ?>> possibleEntityTypes = getDataStore().readNode(ENTITY_TYPES_PATH);
 371         if(!possibleEntityTypes.isPresent()) {
 372             return;
 373         }
 374
 375         for(MapEntryNode entityType:  ((MapNode) possibleEntityTypes.get()).getValue()) {
 376             Optional<DataContainerChild<? extends PathArgument, ?>> possibleEntities =
 377                     entityType.getChild(ENTITY_NODE_ID);
 378             if(!possibleEntities.isPresent()) {
 379                 continue; // shouldn't happen but handle anyway
 380             }
 381
 382             for(MapEntryNode entity:  ((MapNode) possibleEntities.get()).getValue()) {
 383                 walker.onEntity(entityType, entity);
 384             }
 385         }
 386     }
 387
 388     private static Collection<String> getCandidateNames(MapEntryNode entity) {
 389         Collection<MapEntryNode> candidates = ((MapNode)entity.getChild(CANDIDATE_NODE_ID).get()).getValue();
 390         Collection<String> candidateNames = new ArrayList<>(candidates.size());
 391         for(MapEntryNode candidate: candidates) {
 392             candidateNames.add(candidate.getChild(CANDIDATE_NAME_NODE_ID).get().getValue().toString());
 393         }
 394
 395         return candidateNames;
 396     }
 397
 398     private void writeNewOwner(YangInstanceIdentifier entityPath, String newOwner) {
 399         LOG.debug("{}: Writing new owner {} for entity {}", persistenceId(), newOwner, entityPath);
 400
 401         commitCoordinator.commitModification(new WriteModification(entityPath.node(ENTITY_OWNER_QNAME),
 402                 ImmutableNodes.leafNode(ENTITY_OWNER_NODE_ID, newOwner)), this);
 403     }
 404
 405     private String newOwner(Collection<String> candidates) {
 406         for(String candidate: candidates) {
 407             if(!downPeerMemberNames.contains(candidate)) {
 408                 return candidate;
 409             }
 410         }
 411
 412         return "";
 413     }
 414
 415     private String getCurrentOwner(YangInstanceIdentifier entityId) {
 416         Optional<NormalizedNode<?, ?>> optionalEntityOwner = getDataStore().readNode(entityId.node(ENTITY_OWNER_QNAME));
 417         if(optionalEntityOwner.isPresent()){
 418             return optionalEntityOwner.get().getValue().toString();
 419         }
 420         return null;
 421     }
 422
 423     public static Props props(final ShardIdentifier name, final Map<String, String> peerAddresses,
 424             final DatastoreContext datastoreContext, final SchemaContext schemaContext, final String localMemberName) {
 425         return Props.create(new Creator(name, peerAddresses, datastoreContext, schemaContext, localMemberName));
 426     }
 427
 428     private static class Creator extends AbstractShardCreator {
 429         private static final long serialVersionUID = 1L;
 430
 431         private final String localMemberName;
 432
 433         Creator(final ShardIdentifier name, final Map<String, String> peerAddresses,
 434                 final DatastoreContext datastoreContext, final SchemaContext schemaContext,
 435                 final String localMemberName) {
 436             super(name, peerAddresses, datastoreContext, schemaContext);
 437             this.localMemberName = localMemberName;
 438         }
 439
 440         @Override
 441         public Shard create() throws Exception {
 442             return new EntityOwnershipShard(name, peerAddresses, datastoreContext, schemaContext, localMemberName);
 443         }
 444     }
 445
 446     private static interface EntityWalker {
 447         void onEntity(MapEntryNode entityTypeNode, MapEntryNode entityNode);
 448     }
 449 }