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_NODE_ID;
  13 import static org.opendaylight.controller.cluster.datastore.entityownership.EntityOwnersModel.ENTITY_OWNERS_PATH;
  14 import static org.opendaylight.controller.cluster.datastore.entityownership.EntityOwnersModel.ENTITY_OWNER_NODE_ID;
  15 import static org.opendaylight.controller.cluster.datastore.entityownership.EntityOwnersModel.ENTITY_OWNER_QNAME;
  16 import static org.opendaylight.controller.cluster.datastore.entityownership.EntityOwnersModel.ENTITY_TYPES_PATH;
  17 import static org.opendaylight.controller.cluster.datastore.entityownership.EntityOwnersModel.candidatePath;
  18 import static org.opendaylight.controller.cluster.datastore.entityownership.EntityOwnersModel.entityOwnersWithCandidate;
  19 import akka.actor.ActorRef;
  20 import akka.actor.ActorSelection;
  21 import akka.actor.Props;
  22 import akka.pattern.Patterns;
  23 import com.google.common.base.Optional;
  24 import com.google.common.base.Strings;
  25 import java.util.ArrayList;
  26 import java.util.Collection;
  27 import java.util.HashMap;
  28 import java.util.HashSet;
  29 import java.util.Map;
  30 import java.util.Set;
  31 import java.util.concurrent.TimeUnit;
  32 import org.opendaylight.controller.cluster.datastore.DatastoreContext;
  33 import org.opendaylight.controller.cluster.datastore.Shard;
  34 import org.opendaylight.controller.cluster.datastore.entityownership.messages.CandidateAdded;
  35 import org.opendaylight.controller.cluster.datastore.entityownership.messages.CandidateRemoved;
  36 import org.opendaylight.controller.cluster.datastore.entityownership.messages.RegisterCandidateLocal;
  37 import org.opendaylight.controller.cluster.datastore.entityownership.messages.UnregisterCandidateLocal;
  38 import org.opendaylight.controller.cluster.datastore.identifiers.ShardIdentifier;
  39 import org.opendaylight.controller.cluster.datastore.messages.BatchedModifications;
  40 import org.opendaylight.controller.cluster.datastore.messages.PeerDown;
  41 import org.opendaylight.controller.cluster.datastore.messages.PeerUp;
  42 import org.opendaylight.controller.cluster.datastore.messages.SuccessReply;
  43 import org.opendaylight.controller.cluster.datastore.modification.DeleteModification;
  44 import org.opendaylight.controller.cluster.datastore.modification.MergeModification;
  45 import org.opendaylight.controller.cluster.datastore.modification.WriteModification;
  46 import org.opendaylight.controller.md.sal.common.api.clustering.Entity;
  47 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  48 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
  49 import org.opendaylight.yangtools.yang.data.api.schema.DataContainerChild;
  50 import org.opendaylight.yangtools.yang.data.api.schema.MapEntryNode;
  51 import org.opendaylight.yangtools.yang.data.api.schema.MapNode;
  52 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  53 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeSnapshot;
  54 import org.opendaylight.yangtools.yang.data.impl.schema.ImmutableNodes;
  55 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  56 import scala.concurrent.Future;
  57
  58 /**
  59  * Special Shard for EntityOwnership.
  60  *
  61  * @author Thomas Pantelis
  62  */
  63 class EntityOwnershipShard extends Shard {
  64     private final String localMemberName;
  65     private final EntityOwnershipShardCommitCoordinator commitCoordinator;
  66     private final EntityOwnershipListenerSupport listenerSupport;
  67     private final Set<String> downPeerMemberNames = new HashSet<>();
  68     private final Map<String, String> peerIdToMemberNames = new HashMap<>();
  69
  70     private static DatastoreContext noPersistenceDatastoreContext(DatastoreContext datastoreContext) {
  71         return DatastoreContext.newBuilderFrom(datastoreContext).persistent(false).build();
  72     }
  73
  74     protected EntityOwnershipShard(ShardIdentifier name, Map<String, String> peerAddresses,
  75             DatastoreContext datastoreContext, SchemaContext schemaContext, String localMemberName) {
  76         super(name, peerAddresses, noPersistenceDatastoreContext(datastoreContext), schemaContext);
  77         this.localMemberName = localMemberName;
  78         this.commitCoordinator = new EntityOwnershipShardCommitCoordinator(localMemberName, LOG);
  79         this.listenerSupport = new EntityOwnershipListenerSupport(getContext());
  80
  81         for(String peerId: peerAddresses.keySet()) {
  82             ShardIdentifier shardId = ShardIdentifier.builder().fromShardIdString(peerId).build();
  83             peerIdToMemberNames.put(peerId, shardId.getMemberName());
  84         }
  85     }
  86
  87     @Override
  88     protected void onDatastoreContext(DatastoreContext context) {
  89         super.onDatastoreContext(noPersistenceDatastoreContext(context));
  90     }
  91
  92     @Override
  93     protected void onRecoveryComplete() {
  94         super.onRecoveryComplete();
  95
  96         new CandidateListChangeListener(getSelf()).init(getDataStore());
  97         new EntityOwnerChangeListener(localMemberName, listenerSupport).init(getDataStore());
  98     }
  99
 100     @Override
 101     public void onReceiveCommand(final Object message) throws Exception {
 102         if(message instanceof RegisterCandidateLocal) {
 103             onRegisterCandidateLocal((RegisterCandidateLocal)message);
 104         } else if(message instanceof UnregisterCandidateLocal) {
 105             onUnregisterCandidateLocal((UnregisterCandidateLocal)message);
 106         } else if(message instanceof CandidateAdded){
 107             onCandidateAdded((CandidateAdded) message);
 108         } else if(message instanceof CandidateRemoved){
 109             onCandidateRemoved((CandidateRemoved) message);
 110         } else if(message instanceof PeerDown) {
 111             onPeerDown((PeerDown) message);
 112         } else if(message instanceof PeerUp) {
 113             onPeerUp((PeerUp) message);
 114         } else if(!commitCoordinator.handleMessage(message, this)) {
 115             super.onReceiveCommand(message);
 116         }
 117     }
 118
 119     private void onRegisterCandidateLocal(RegisterCandidateLocal registerCandidate) {
 120         LOG.debug("{}: onRegisterCandidateLocal: {}", persistenceId(), registerCandidate);
 121
 122         listenerSupport.addEntityOwnershipListener(registerCandidate.getEntity(), registerCandidate.getCandidate());
 123
 124         NormalizedNode<?, ?> entityOwners = entityOwnersWithCandidate(registerCandidate.getEntity().getType(),
 125                 registerCandidate.getEntity().getId(), localMemberName);
 126         commitCoordinator.commitModification(new MergeModification(ENTITY_OWNERS_PATH, entityOwners), this);
 127
 128         getSender().tell(SuccessReply.INSTANCE, getSelf());
 129     }
 130
 131     private void onUnregisterCandidateLocal(UnregisterCandidateLocal unregisterCandidate) {
 132         LOG.debug("{}: onUnregisterCandidateLocal: {}", persistenceId(), unregisterCandidate);
 133
 134         Entity entity = unregisterCandidate.getEntity();
 135         listenerSupport.removeEntityOwnershipListener(entity, unregisterCandidate.getCandidate());
 136
 137         YangInstanceIdentifier candidatePath = candidatePath(entity.getType(), entity.getId(), localMemberName);
 138         commitCoordinator.commitModification(new DeleteModification(candidatePath), this);
 139
 140         getSender().tell(SuccessReply.INSTANCE, getSelf());
 141     }
 142
 143     void tryCommitModifications(final BatchedModifications modifications) {
 144         if(isLeader()) {
 145             LOG.debug("{}: Committing BatchedModifications {} locally", persistenceId(), modifications.getTransactionID());
 146
 147             // Note that it's possible the commit won't get consensus and will timeout and not be applied
 148             // to the state. However we don't need to retry it in that case b/c it will be committed to
 149             // the journal first and, once a majority of followers come back on line and it is replicated,
 150             // it will be applied at that point.
 151             handleBatchedModificationsLocal(modifications, self());
 152         } else {
 153             final ActorSelection leader = getLeader();
 154             if (leader != null) {
 155                 if(LOG.isDebugEnabled()) {
 156                     LOG.debug("{}: Sending BatchedModifications {} to leader {}", persistenceId(),
 157                             modifications.getTransactionID(), leader);
 158                 }
 159
 160                 Future<Object> future = Patterns.ask(leader, modifications, TimeUnit.SECONDS.toMillis(
 161                         getDatastoreContext().getShardTransactionCommitTimeoutInSeconds()));
 162
 163                 Patterns.pipe(future, getContext().dispatcher()).pipeTo(getSelf(), ActorRef.noSender());
 164             }
 165         }
 166     }
 167
 168     boolean hasLeader() {
 169         return getLeader() != null && !isIsolatedLeader();
 170     }
 171
 172     @Override
 173     protected void onStateChanged() {
 174         super.onStateChanged();
 175
 176         commitCoordinator.onStateChanged(this, isLeader());
 177     }
 178
 179     @Override
 180     protected void onLeaderChanged(String oldLeader, String newLeader) {
 181         super.onLeaderChanged(oldLeader, newLeader);
 182
 183         LOG.debug("{}: onLeaderChanged: oldLeader: {}, newLeader: {}, isLeader: {}", persistenceId(), oldLeader,
 184                 newLeader, isLeader());
 185
 186         if(isLeader()) {
 187             // We were just elected leader. If the old leader is down, select new owners for the entities
 188             // owned by the down leader.
 189
 190             String oldLeaderMemberName = peerIdToMemberNames.get(oldLeader);
 191
 192             LOG.debug("{}: oldLeaderMemberName: {}", persistenceId(), oldLeaderMemberName);
 193
 194             if(downPeerMemberNames.contains(oldLeaderMemberName)) {
 195                 selectNewOwnerForEntitiesOwnedBy(oldLeaderMemberName);
 196             }
 197         }
 198     }
 199
 200     private void onCandidateRemoved(CandidateRemoved message) {
 201         if(!isLeader()) {
 202             return;
 203         }
 204
 205         LOG.debug("{}: onCandidateRemoved: {}", persistenceId(), message);
 206
 207         String currentOwner = getCurrentOwner(message.getEntityPath());
 208         if(message.getRemovedCandidate().equals(currentOwner)){
 209             writeNewOwner(message.getEntityPath(), newOwner(message.getRemainingCandidates()));
 210         }
 211     }
 212
 213     private void onCandidateAdded(CandidateAdded message) {
 214         if(!isLeader()){
 215             return;
 216         }
 217
 218         LOG.debug("{}: onCandidateAdded: {}", persistenceId(), message);
 219
 220         String currentOwner = getCurrentOwner(message.getEntityPath());
 221         if(Strings.isNullOrEmpty(currentOwner)){
 222             writeNewOwner(message.getEntityPath(), newOwner(message.getAllCandidates()));
 223         }
 224     }
 225
 226     private void onPeerDown(PeerDown peerDown) {
 227         LOG.debug("{}: onPeerDown: {}", persistenceId(), peerDown);
 228
 229         String downMemberName = peerDown.getMemberName();
 230         if(downPeerMemberNames.add(downMemberName) && isLeader()) {
 231             // Select new owners for entities owned by the down peer.
 232             selectNewOwnerForEntitiesOwnedBy(downMemberName);
 233         }
 234     }
 235
 236     private void onPeerUp(PeerUp peerUp) {
 237         LOG.debug("{}: onPeerUp: {}", persistenceId(), peerUp);
 238
 239         peerIdToMemberNames.put(peerUp.getPeerId(), peerUp.getMemberName());
 240
 241         if(downPeerMemberNames.remove(peerUp.getMemberName()) && isLeader()) {
 242             // This peer was previously down - for its previously owned entities, if there were no other
 243             // candidates, the owner would have been cleared so handle that here by trying to re-assign
 244             // ownership for entities whose owner is cleared.
 245             selectNewOwnerForEntitiesOwnedBy("");
 246         }
 247     }
 248
 249     private void selectNewOwnerForEntitiesOwnedBy(String owner) {
 250         DataTreeSnapshot snapshot = getDataStore().getDataTree().takeSnapshot();
 251         Optional<NormalizedNode<?, ?>> possibleEntityTypes = snapshot.readNode(ENTITY_TYPES_PATH);
 252         if(!possibleEntityTypes.isPresent()) {
 253             return;
 254         }
 255
 256         LOG.debug("{}: Searching for entities owned by {}", persistenceId(), owner);
 257
 258         BatchedModifications modifications = commitCoordinator.newBatchedModifications();
 259         for(MapEntryNode entityType:  ((MapNode) possibleEntityTypes.get()).getValue()) {
 260             Optional<DataContainerChild<? extends PathArgument, ?>> possibleEntities =
 261                     entityType.getChild(ENTITY_NODE_ID);
 262             if(!possibleEntities.isPresent()) {
 263                 continue; // shouldn't happen but handle anyway
 264             }
 265
 266             for(MapEntryNode entity:  ((MapNode) possibleEntities.get()).getValue()) {
 267                 Optional<DataContainerChild<? extends PathArgument, ?>> possibleOwner =
 268                         entity.getChild(ENTITY_OWNER_NODE_ID);
 269                 if(possibleOwner.isPresent() && owner.equals(possibleOwner.get().getValue().toString())) {
 270                     Object newOwner = newOwner(getCandidateNames(entity));
 271                     YangInstanceIdentifier entityPath = YangInstanceIdentifier.builder(ENTITY_TYPES_PATH).
 272                             node(entityType.getIdentifier()).node(ENTITY_NODE_ID).node(entity.getIdentifier()).
 273                                     node(ENTITY_OWNER_NODE_ID).build();
 274
 275                     LOG.debug("{}: Found entity {}, writing new owner {}", persistenceId(), entityPath, newOwner);
 276
 277                     modifications.addModification(new WriteModification(entityPath,
 278                             ImmutableNodes.leafNode(ENTITY_OWNER_NODE_ID, newOwner)));
 279                 }
 280             }
 281         }
 282
 283         commitCoordinator.commitModifications(modifications, this);
 284     }
 285
 286     private Collection<String> getCandidateNames(MapEntryNode entity) {
 287         Collection<MapEntryNode> candidates = ((MapNode)entity.getChild(CANDIDATE_NODE_ID).get()).getValue();
 288         Collection<String> candidateNames = new ArrayList<>(candidates.size());
 289         for(MapEntryNode candidate: candidates) {
 290             candidateNames.add(candidate.getChild(CANDIDATE_NAME_NODE_ID).get().getValue().toString());
 291         }
 292
 293         return candidateNames;
 294     }
 295
 296     private void writeNewOwner(YangInstanceIdentifier entityPath, String newOwner) {
 297         LOG.debug("{}: Writing new owner {} for entity {}", persistenceId(), newOwner, entityPath);
 298
 299         commitCoordinator.commitModification(new WriteModification(entityPath.node(ENTITY_OWNER_QNAME),
 300                 ImmutableNodes.leafNode(ENTITY_OWNER_NODE_ID, newOwner)), this);
 301     }
 302
 303     private String newOwner(Collection<String> candidates) {
 304         for(String candidate: candidates) {
 305             if(!downPeerMemberNames.contains(candidate)) {
 306                 return candidate;
 307             }
 308         }
 309
 310         return "";
 311     }
 312
 313     private String getCurrentOwner(YangInstanceIdentifier entityId) {
 314         DataTreeSnapshot snapshot = getDataStore().getDataTree().takeSnapshot();
 315         Optional<NormalizedNode<?, ?>> optionalEntityOwner = snapshot.readNode(entityId.node(ENTITY_OWNER_QNAME));
 316         if(optionalEntityOwner.isPresent()){
 317             return optionalEntityOwner.get().getValue().toString();
 318         }
 319         return null;
 320     }
 321
 322     public static Props props(final ShardIdentifier name, final Map<String, String> peerAddresses,
 323             final DatastoreContext datastoreContext, final SchemaContext schemaContext, final String localMemberName) {
 324         return Props.create(new Creator(name, peerAddresses, datastoreContext, schemaContext, localMemberName));
 325     }
 326
 327     private static class Creator extends AbstractShardCreator {
 328         private static final long serialVersionUID = 1L;
 329
 330         private final String localMemberName;
 331
 332         Creator(final ShardIdentifier name, final Map<String, String> peerAddresses,
 333                 final DatastoreContext datastoreContext, final SchemaContext schemaContext,
 334                 final String localMemberName) {
 335             super(name, peerAddresses, datastoreContext, schemaContext);
 336             this.localMemberName = localMemberName;
 337         }
 338
 339         @Override
 340         public Shard create() throws Exception {
 341             return new EntityOwnershipShard(name, peerAddresses, datastoreContext, schemaContext, localMemberName);
 342         }
 343     }
 344 }