Allow passing of delay to the EntityOwnerElectionStrategy
[controller.git] / opendaylight / md-sal / sal-distributed-datastore / src / main / java / org / opendaylight / controller / cluster / datastore / entityownership / EntityOwnershipShard.java
index e14ae7f5376e8e2f763b24dfe745bb82970d90c1..2f3b51e1d1d7ae4c8c2e73cde2ef49788c0fe3c0 100644 (file)
@@ -25,7 +25,9 @@ import static org.opendaylight.controller.cluster.datastore.entityownership.Enti
 import static org.opendaylight.controller.cluster.datastore.entityownership.EntityOwnersModel.entityOwnersWithCandidate;
 import akka.actor.ActorRef;
 import akka.actor.ActorSelection;
+import akka.actor.Cancellable;
 import akka.pattern.Patterns;
+import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Optional;
 import com.google.common.base.Preconditions;
 import com.google.common.base.Strings;
@@ -42,10 +44,11 @@ import org.opendaylight.controller.cluster.datastore.entityownership.messages.Ca
 import org.opendaylight.controller.cluster.datastore.entityownership.messages.CandidateRemoved;
 import org.opendaylight.controller.cluster.datastore.entityownership.messages.RegisterCandidateLocal;
 import org.opendaylight.controller.cluster.datastore.entityownership.messages.RegisterListenerLocal;
+import org.opendaylight.controller.cluster.datastore.entityownership.messages.SelectOwner;
 import org.opendaylight.controller.cluster.datastore.entityownership.messages.UnregisterCandidateLocal;
 import org.opendaylight.controller.cluster.datastore.entityownership.messages.UnregisterListenerLocal;
 import org.opendaylight.controller.cluster.datastore.entityownership.selectionstrategy.EntityOwnerSelectionStrategy;
-import org.opendaylight.controller.cluster.datastore.entityownership.selectionstrategy.FirstCandidateSelectionStrategy;
+import org.opendaylight.controller.cluster.datastore.entityownership.selectionstrategy.EntityOwnerSelectionStrategyConfig;
 import org.opendaylight.controller.cluster.datastore.identifiers.ShardIdentifier;
 import org.opendaylight.controller.cluster.datastore.messages.BatchedModifications;
 import org.opendaylight.controller.cluster.datastore.messages.PeerDown;
@@ -63,6 +66,7 @@ import org.opendaylight.yangtools.yang.data.api.schema.MapNode;
 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
 import org.opendaylight.yangtools.yang.data.impl.schema.ImmutableNodes;
 import scala.concurrent.Future;
+import scala.concurrent.duration.FiniteDuration;
 
 /**
  * Special Shard for EntityOwnership.
@@ -70,16 +74,13 @@ import scala.concurrent.Future;
  * @author Thomas Pantelis
  */
 class EntityOwnershipShard extends Shard {
-
-    private static final EntityOwnerSelectionStrategy DEFAULT_ENTITY_OWNER_SELECTION_STRATEGY
-            = FirstCandidateSelectionStrategy.INSTANCE;
-
     private final String localMemberName;
     private final EntityOwnershipShardCommitCoordinator commitCoordinator;
     private final EntityOwnershipListenerSupport listenerSupport;
     private final Set<String> downPeerMemberNames = new HashSet<>();
     private final Map<String, String> peerIdToMemberNames = new HashMap<>();
-    private final Map<String, EntityOwnerSelectionStrategy> ownerSelectionStrategies = new HashMap<>();
+    private EntityOwnerSelectionStrategyConfig strategyConfig;
+    private Map<YangInstanceIdentifier, Cancellable> entityToScheduledOwnershipTask = new HashMap<>();
 
     private static DatastoreContext noPersistenceDatastoreContext(DatastoreContext datastoreContext) {
         return DatastoreContext.newBuilderFrom(datastoreContext).persistent(false).build();
@@ -90,6 +91,7 @@ class EntityOwnershipShard extends Shard {
         this.localMemberName = builder.localMemberName;
         this.commitCoordinator = new EntityOwnershipShardCommitCoordinator(builder.localMemberName, LOG);
         this.listenerSupport = new EntityOwnershipListenerSupport(getContext(), persistenceId());
+        this.strategyConfig = EntityOwnerSelectionStrategyConfig.newBuilder().build();
 
         for(String peerId: getRaftActorContext().getPeerIds()) {
             ShardIdentifier shardId = ShardIdentifier.builder().fromShardIdString(peerId).build();
@@ -113,7 +115,7 @@ class EntityOwnershipShard extends Shard {
     @Override
     public void onReceiveCommand(final Object message) throws Exception {
         if(message instanceof RegisterCandidateLocal) {
-            onRegisterCandidateLocal((RegisterCandidateLocal)message);
+            onRegisterCandidateLocal((RegisterCandidateLocal) message);
         } else if(message instanceof UnregisterCandidateLocal) {
             onUnregisterCandidateLocal((UnregisterCandidateLocal)message);
         } else if(message instanceof CandidateAdded){
@@ -124,15 +126,33 @@ class EntityOwnershipShard extends Shard {
             onPeerDown((PeerDown) message);
         } else if(message instanceof PeerUp) {
             onPeerUp((PeerUp) message);
-        } if(message instanceof RegisterListenerLocal) {
+        } else if(message instanceof RegisterListenerLocal) {
             onRegisterListenerLocal((RegisterListenerLocal)message);
-        } if(message instanceof UnregisterListenerLocal) {
-            onUnregisterListenerLocal((UnregisterListenerLocal)message);
+        } else if(message instanceof UnregisterListenerLocal) {
+            onUnregisterListenerLocal((UnregisterListenerLocal) message);
+        } else if(message instanceof SelectOwner) {
+            onSelectOwner((SelectOwner) message);
         } else if(!commitCoordinator.handleMessage(message, this)) {
             super.onReceiveCommand(message);
         }
     }
 
+    private void onSelectOwner(SelectOwner selectOwner) {
+        String currentOwner = getCurrentOwner(selectOwner.getEntityPath());
+        if(Strings.isNullOrEmpty(currentOwner)) {
+            writeNewOwner(selectOwner.getEntityPath(), newOwner(selectOwner.getAllCandidates(),
+                    selectOwner.getOwnerSelectionStrategy()));
+
+            Cancellable cancellable = entityToScheduledOwnershipTask.get(selectOwner.getEntityPath());
+            if(cancellable != null){
+                if(!cancellable.isCancelled()){
+                    cancellable.cancel();
+                }
+                entityToScheduledOwnershipTask.remove(selectOwner.getEntityPath());
+            }
+        }
+    }
+
     private void onRegisterCandidateLocal(RegisterCandidateLocal registerCandidate) {
         LOG.debug("{}: onRegisterCandidateLocal: {}", persistenceId(), registerCandidate);
 
@@ -250,8 +270,8 @@ class EntityOwnershipShard extends Shard {
         if(isLeader()) {
             String currentOwner = getCurrentOwner(message.getEntityPath());
             if(message.getRemovedCandidate().equals(currentOwner)){
-                writeNewOwner(message.getEntityPath(), newOwner(message.getRemainingCandidates(),
-                        getEntityOwnerElectionStrategy(message.getEntityPath())));
+                writeNewOwner(message.getEntityPath(),
+                        newOwner(message.getRemainingCandidates(), getEntityOwnerElectionStrategy(message.getEntityPath())));
             }
         } else {
             // We're not the leader. If the removed candidate is our local member then check if we actually
@@ -272,15 +292,8 @@ class EntityOwnershipShard extends Shard {
     }
 
     private EntityOwnerSelectionStrategy getEntityOwnerElectionStrategy(YangInstanceIdentifier entityPath) {
-        String entityType = EntityOwnersModel.entityTypeFromEntityPath(entityPath);
-        EntityOwnerSelectionStrategy entityOwnerSelectionStrategy = ownerSelectionStrategies.get(entityType);
-
-        if(entityOwnerSelectionStrategy == null){
-            entityOwnerSelectionStrategy = DEFAULT_ENTITY_OWNER_SELECTION_STRATEGY;
-            ownerSelectionStrategies.put(entityType, entityOwnerSelectionStrategy);
-        }
-
-        return entityOwnerSelectionStrategy;
+        final String entityType = EntityOwnersModel.entityTypeFromEntityPath(entityPath);
+        return strategyConfig.createStrategy(entityType);
     }
 
     private void onCandidateAdded(CandidateAdded message) {
@@ -295,14 +308,12 @@ class EntityOwnershipShard extends Shard {
         downPeerMemberNames.remove(message.getNewCandidate());
 
         String currentOwner = getCurrentOwner(message.getEntityPath());
+        EntityOwnerSelectionStrategy strategy = getEntityOwnerElectionStrategy(message.getEntityPath());
         if(Strings.isNullOrEmpty(currentOwner)){
-            EntityOwnerSelectionStrategy entityOwnerSelectionStrategy
-                    = getEntityOwnerElectionStrategy(message.getEntityPath());
-            if(entityOwnerSelectionStrategy.selectionDelayInMillis() == 0L) {
-                writeNewOwner(message.getEntityPath(), newOwner(message.getAllCandidates(),
-                        entityOwnerSelectionStrategy));
+            if(strategy.getSelectionDelayInMillis() == 0L) {
+                writeNewOwner(message.getEntityPath(), newOwner(message.getAllCandidates(), strategy));
             } else {
-                throw new UnsupportedOperationException("Delayed selection not implemented yet");
+                scheduleOwnerSelection(message.getEntityPath(), message.getAllCandidates(), strategy);
             }
         }
     }
@@ -351,9 +362,9 @@ class EntityOwnershipShard extends Shard {
         searchForEntities(new EntityWalker() {
             @Override
             public void onEntity(MapEntryNode entityTypeNode, MapEntryNode entityNode) {
-                if(hasCandidate(entityNode, owner)) {
+                if (hasCandidate(entityNode, owner)) {
                     YangInstanceIdentifier entityId =
-                            (YangInstanceIdentifier)entityNode.getIdentifier().getKeyValues().get(ENTITY_ID_QNAME);
+                            (YangInstanceIdentifier) entityNode.getIdentifier().getKeyValues().get(ENTITY_ID_QNAME);
                     YangInstanceIdentifier candidatePath = candidatePath(
                             entityTypeNode.getIdentifier().getKeyValues().get(ENTITY_TYPE_QNAME).toString(),
                             entityId, owner);
@@ -412,8 +423,8 @@ class EntityOwnershipShard extends Shard {
         }
     }
 
-    private static Collection<String> getCandidateNames(MapEntryNode entity) {
-        Collection<MapEntryNode> candidates = ((MapNode)entity.getChild(CANDIDATE_NODE_ID).get()).getValue();
+    private Collection<String> getCandidateNames(MapEntryNode entity) {
+        Collection<MapEntryNode> candidates = ((MapNode) entity.getChild(CANDIDATE_NODE_ID).get()).getValue();
         Collection<String> candidateNames = new ArrayList<>(candidates.size());
         for(MapEntryNode candidate: candidates) {
             candidateNames.add(candidate.getChild(CANDIDATE_NAME_NODE_ID).get().getValue().toString());
@@ -429,6 +440,26 @@ class EntityOwnershipShard extends Shard {
                 ImmutableNodes.leafNode(ENTITY_OWNER_NODE_ID, newOwner)), this);
     }
 
+    /**
+     * Schedule a new owner selection job. Cancelling any outstanding job if it has not been cancelled.
+     *
+     * @param entityPath
+     * @param allCandidates
+     */
+    public void scheduleOwnerSelection(YangInstanceIdentifier entityPath, Collection<String> allCandidates,
+                                       EntityOwnerSelectionStrategy strategy){
+        Cancellable lastScheduledTask = entityToScheduledOwnershipTask.get(entityPath);
+        if(lastScheduledTask != null && !lastScheduledTask.isCancelled()){
+            lastScheduledTask.cancel();
+        }
+        lastScheduledTask = context().system().scheduler().scheduleOnce(
+                FiniteDuration.apply(strategy.getSelectionDelayInMillis(), TimeUnit.MILLISECONDS)
+                , self(), new SelectOwner(entityPath, allCandidates, strategy)
+                , context().system().dispatcher(), self());
+
+        entityToScheduledOwnershipTask.put(entityPath, lastScheduledTask);
+    }
+
     private String newOwner(Collection<String> candidates, EntityOwnerSelectionStrategy ownerSelectionStrategy) {
         Collection<String> viableCandidates = getViableCandidates(candidates);
         if(viableCandidates.size() == 0){
@@ -460,6 +491,15 @@ class EntityOwnershipShard extends Shard {
         void onEntity(MapEntryNode entityTypeNode, MapEntryNode entityNode);
     }
 
+    @VisibleForTesting
+    void addEntityOwnerSelectionStrategy(String entityType,
+                                         Class<? extends EntityOwnerSelectionStrategy> clazz,
+                                         long delay){
+        EntityOwnerSelectionStrategyConfig config = EntityOwnerSelectionStrategyConfig.newBuilder()
+                .addStrategy(entityType, clazz, delay).build();
+        this.strategyConfig = config;
+    }
+
     public static Builder newBuilder() {
         return new Builder();
     }