+
+ searchForEntitiesOwnedBy(localMemberName, new EntityWalker() {
+ @Override
+ public void onEntity(MapEntryNode entityTypeNode, MapEntryNode entityNode) {
+ Optional<DataContainerChild<? extends PathArgument, ?>> possibleType =
+ entityTypeNode.getChild(ENTITY_TYPE_NODE_ID);
+ String entityType = possibleType.isPresent() ? possibleType.get().getValue().toString() : null;
+ if (registerListener.getEntityType().equals(entityType)) {
+ Entity entity = new Entity(entityType,
+ (YangInstanceIdentifier) entityNode.getChild(ENTITY_ID_NODE_ID).get().getValue());
+ listenerSupport.notifyEntityOwnershipListener(entity, false, true, true, registerListener.getListener());
+ }
+ }
+ });
+ }
+
+ private void onUnregisterListenerLocal(UnregisterListenerLocal unregisterListener) {
+ LOG.debug("{}: onUnregisterListenerLocal: {}", persistenceId(), unregisterListener);
+
+ listenerSupport.removeEntityOwnershipListener(unregisterListener.getEntityType(), unregisterListener.getListener());
+
+ getSender().tell(SuccessReply.INSTANCE, getSelf());
+ }
+
+ void tryCommitModifications(final BatchedModifications modifications) {
+ if(isLeader()) {
+ LOG.debug("{}: Committing BatchedModifications {} locally", persistenceId(), modifications.getTransactionID());
+
+ // Note that it's possible the commit won't get consensus and will timeout and not be applied
+ // to the state. However we don't need to retry it in that case b/c it will be committed to
+ // the journal first and, once a majority of followers come back on line and it is replicated,
+ // it will be applied at that point.
+ handleBatchedModificationsLocal(modifications, self());
+ } else {
+ final ActorSelection leader = getLeader();
+ if (leader != null) {
+ if(LOG.isDebugEnabled()) {
+ LOG.debug("{}: Sending BatchedModifications {} to leader {}", persistenceId(),
+ modifications.getTransactionID(), leader);
+ }
+
+ Future<Object> future = Patterns.ask(leader, modifications, TimeUnit.SECONDS.toMillis(
+ getDatastoreContext().getShardTransactionCommitTimeoutInSeconds()));
+
+ Patterns.pipe(future, getContext().dispatcher()).pipeTo(getSelf(), ActorRef.noSender());
+ }
+ }
+ }
+
+ boolean hasLeader() {
+ return getLeader() != null && !isIsolatedLeader();
+ }
+
+ @Override
+ protected void onStateChanged() {
+ super.onStateChanged();
+
+ commitCoordinator.onStateChanged(this, isLeader());
+ }
+
+ @Override
+ protected void onLeaderChanged(String oldLeader, String newLeader) {
+ super.onLeaderChanged(oldLeader, newLeader);
+
+ LOG.debug("{}: onLeaderChanged: oldLeader: {}, newLeader: {}, isLeader: {}", persistenceId(), oldLeader,
+ newLeader, isLeader());
+
+ if(isLeader()) {
+ // We were just elected leader. If the old leader is down, select new owners for the entities
+ // owned by the down leader.
+
+ String oldLeaderMemberName = peerIdToMemberNames.get(oldLeader);
+
+ LOG.debug("{}: oldLeaderMemberName: {}", persistenceId(), oldLeaderMemberName);
+
+ if(downPeerMemberNames.contains(oldLeaderMemberName)) {
+ selectNewOwnerForEntitiesOwnedBy(oldLeaderMemberName);
+ }
+ }
+ }
+
+ private void onCandidateRemoved(CandidateRemoved message) {
+ LOG.debug("{}: onCandidateRemoved: {}", persistenceId(), message);
+
+ if(isLeader()) {
+ String currentOwner = getCurrentOwner(message.getEntityPath());
+ if(message.getRemovedCandidate().equals(currentOwner)){
+ 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
+ // have a local candidate registered. If we do then we must have been partitioned from the leader
+ // and the leader removed our candidate since the leader can't tell the difference between a
+ // temporary network partition and a node's process actually restarted. So, in that case, re-add
+ // our candidate.
+ if(localMemberName.equals(message.getRemovedCandidate()) &&
+ listenerSupport.hasCandidateForEntity(createEntity(message.getEntityPath()))) {
+ LOG.debug("Local candidate member was removed but a local candidate is registered for {}" +
+ " - adding back local candidate", message.getEntityPath());
+
+ commitCoordinator.commitModification(new MergeModification(
+ candidatePath(message.getEntityPath(), localMemberName),
+ candidateMapEntry(localMemberName)), this);
+ }
+ }
+ }
+
+ private EntityOwnerSelectionStrategy getEntityOwnerElectionStrategy(YangInstanceIdentifier entityPath) {
+ final String entityType = EntityOwnersModel.entityTypeFromEntityPath(entityPath);
+ return strategyConfig.createStrategy(entityType);
+ }
+
+ private void onCandidateAdded(CandidateAdded message) {
+ if(!isLeader()){
+ return;
+ }
+
+ LOG.debug("{}: onCandidateAdded: {}", persistenceId(), message);
+
+ // Since a node's candidate member is only added by the node itself, we can assume the node is up so
+ // remove it from the downPeerMemberNames.
+ downPeerMemberNames.remove(message.getNewCandidate());
+
+ String currentOwner = getCurrentOwner(message.getEntityPath());
+ EntityOwnerSelectionStrategy strategy = getEntityOwnerElectionStrategy(message.getEntityPath());
+ if(Strings.isNullOrEmpty(currentOwner)){
+ if(strategy.getSelectionDelayInMillis() == 0L) {
+ writeNewOwner(message.getEntityPath(), newOwner(message.getAllCandidates(), strategy));
+ } else {
+ scheduleOwnerSelection(message.getEntityPath(), message.getAllCandidates(), strategy);
+ }
+ }
+ }
+
+ private void onPeerDown(PeerDown peerDown) {
+ LOG.info("{}: onPeerDown: {}", persistenceId(), peerDown);
+
+ String downMemberName = peerDown.getMemberName();
+ if(downPeerMemberNames.add(downMemberName) && isLeader()) {
+ // Remove the down peer as a candidate from all entities.
+ removeCandidateFromEntities(downMemberName);
+ }
+ }
+
+ private void onPeerUp(PeerUp peerUp) {
+ LOG.debug("{}: onPeerUp: {}", persistenceId(), peerUp);
+
+ peerIdToMemberNames.put(peerUp.getPeerId(), peerUp.getMemberName());
+ downPeerMemberNames.remove(peerUp.getMemberName());
+ }
+
+ private void selectNewOwnerForEntitiesOwnedBy(String owner) {
+ final BatchedModifications modifications = commitCoordinator.newBatchedModifications();
+ searchForEntitiesOwnedBy(owner, new EntityWalker() {
+ @Override
+ public void onEntity(MapEntryNode entityTypeNode, MapEntryNode entityNode) {
+
+ YangInstanceIdentifier entityPath = YangInstanceIdentifier.builder(ENTITY_TYPES_PATH).
+ node(entityTypeNode.getIdentifier()).node(ENTITY_NODE_ID).node(entityNode.getIdentifier()).
+ node(ENTITY_OWNER_NODE_ID).build();
+
+ Object newOwner = newOwner(getCandidateNames(entityNode), getEntityOwnerElectionStrategy(entityPath));
+
+ LOG.debug("{}: Found entity {}, writing new owner {}", persistenceId(), entityPath, newOwner);
+
+ modifications.addModification(new WriteModification(entityPath,
+ ImmutableNodes.leafNode(ENTITY_OWNER_NODE_ID, newOwner)));
+ }
+ });
+
+ commitCoordinator.commitModifications(modifications, this);
+ }
+
+ private void removeCandidateFromEntities(final String owner) {
+ final BatchedModifications modifications = commitCoordinator.newBatchedModifications();
+ searchForEntities(new EntityWalker() {
+ @Override
+ public void onEntity(MapEntryNode entityTypeNode, MapEntryNode entityNode) {
+ if (hasCandidate(entityNode, owner)) {
+ YangInstanceIdentifier entityId =
+ (YangInstanceIdentifier) entityNode.getIdentifier().getKeyValues().get(ENTITY_ID_QNAME);
+ YangInstanceIdentifier candidatePath = candidatePath(
+ entityTypeNode.getIdentifier().getKeyValues().get(ENTITY_TYPE_QNAME).toString(),
+ entityId, owner);
+
+ LOG.info("{}: Found entity {}, removing candidate {}, path {}", persistenceId(), entityId,
+ owner, candidatePath);
+
+ modifications.addModification(new DeleteModification(candidatePath));
+ }
+ }
+ });
+
+ commitCoordinator.commitModifications(modifications, this);
+ }
+
+ private static boolean hasCandidate(MapEntryNode entity, String candidateName) {
+ return ((MapNode)entity.getChild(CANDIDATE_NODE_ID).get()).getChild(candidateNodeKey(candidateName)).isPresent();
+ }
+
+ private void searchForEntitiesOwnedBy(final String owner, final EntityWalker walker) {
+ Optional<NormalizedNode<?, ?>> possibleEntityTypes = getDataStore().readNode(ENTITY_TYPES_PATH);
+ if(!possibleEntityTypes.isPresent()) {
+ return;
+ }
+
+ LOG.debug("{}: Searching for entities owned by {}", persistenceId(), owner);
+
+ searchForEntities(new EntityWalker() {
+ @Override
+ public void onEntity(MapEntryNode entityTypeNode, MapEntryNode entityNode) {
+ Optional<DataContainerChild<? extends PathArgument, ?>> possibleOwner =
+ entityNode.getChild(ENTITY_OWNER_NODE_ID);
+ if (possibleOwner.isPresent() && owner.equals(possibleOwner.get().getValue().toString())) {
+ walker.onEntity(entityTypeNode, entityNode);
+ }
+ }
+ });
+ }
+
+ private void searchForEntities(EntityWalker walker) {
+ Optional<NormalizedNode<?, ?>> possibleEntityTypes = getDataStore().readNode(ENTITY_TYPES_PATH);
+ if(!possibleEntityTypes.isPresent()) {
+ return;
+ }
+
+ for(MapEntryNode entityType: ((MapNode) possibleEntityTypes.get()).getValue()) {
+ Optional<DataContainerChild<? extends PathArgument, ?>> possibleEntities =
+ entityType.getChild(ENTITY_NODE_ID);
+ if(!possibleEntities.isPresent()) {
+ continue; // shouldn't happen but handle anyway
+ }
+
+ for(MapEntryNode entity: ((MapNode) possibleEntities.get()).getValue()) {
+ walker.onEntity(entityType, entity);
+ }
+ }
+ }
+
+ 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());
+ }
+
+ return candidateNames;