+++ /dev/null
-/*
- * Copyright (c) 2015 Brocade Communications Systems, Inc. and others. All rights reserved.
- *
- * This program and the accompanying materials are made available under the
- * terms of the Eclipse Public License v1.0 which accompanies this distribution,
- * and is available at http://www.eclipse.org/legal/epl-v10.html
- */
-package org.opendaylight.controller.cluster.entityownership;
-
-import static java.util.Objects.requireNonNull;
-import static org.opendaylight.controller.cluster.entityownership.EntityOwnersModel.CANDIDATE_NAME_NODE_ID;
-import static org.opendaylight.controller.cluster.entityownership.EntityOwnersModel.CANDIDATE_NODE_ID;
-import static org.opendaylight.controller.cluster.entityownership.EntityOwnersModel.ENTITY_ID_NODE_ID;
-import static org.opendaylight.controller.cluster.entityownership.EntityOwnersModel.ENTITY_ID_QNAME;
-import static org.opendaylight.controller.cluster.entityownership.EntityOwnersModel.ENTITY_NODE_ID;
-import static org.opendaylight.controller.cluster.entityownership.EntityOwnersModel.ENTITY_OWNERS_PATH;
-import static org.opendaylight.controller.cluster.entityownership.EntityOwnersModel.ENTITY_OWNER_NODE_ID;
-import static org.opendaylight.controller.cluster.entityownership.EntityOwnersModel.ENTITY_OWNER_QNAME;
-import static org.opendaylight.controller.cluster.entityownership.EntityOwnersModel.ENTITY_TYPES_PATH;
-import static org.opendaylight.controller.cluster.entityownership.EntityOwnersModel.ENTITY_TYPE_NODE_ID;
-import static org.opendaylight.controller.cluster.entityownership.EntityOwnersModel.ENTITY_TYPE_QNAME;
-import static org.opendaylight.controller.cluster.entityownership.EntityOwnersModel.candidateNodeKey;
-import static org.opendaylight.controller.cluster.entityownership.EntityOwnersModel.candidatePath;
-import static org.opendaylight.controller.cluster.entityownership.EntityOwnersModel.entityOwnersWithCandidate;
-
-import akka.actor.ActorRef;
-import akka.actor.ActorSelection;
-import akka.actor.Cancellable;
-import akka.cluster.Cluster;
-import akka.cluster.ClusterEvent.CurrentClusterState;
-import akka.cluster.Member;
-import akka.cluster.MemberStatus;
-import akka.pattern.Patterns;
-import com.google.common.base.Strings;
-import com.google.common.collect.ImmutableList;
-import com.google.common.collect.ImmutableSet;
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.HashMap;
-import java.util.HashSet;
-import java.util.List;
-import java.util.Map;
-import java.util.Optional;
-import java.util.Set;
-import java.util.concurrent.TimeUnit;
-import org.opendaylight.controller.cluster.access.concepts.MemberName;
-import org.opendaylight.controller.cluster.datastore.DatastoreContext;
-import org.opendaylight.controller.cluster.datastore.Shard;
-import org.opendaylight.controller.cluster.datastore.identifiers.ShardIdentifier;
-import org.opendaylight.controller.cluster.datastore.messages.BatchedModifications;
-import org.opendaylight.controller.cluster.datastore.messages.PeerDown;
-import org.opendaylight.controller.cluster.datastore.messages.PeerUp;
-import org.opendaylight.controller.cluster.datastore.messages.SuccessReply;
-import org.opendaylight.controller.cluster.datastore.modification.DeleteModification;
-import org.opendaylight.controller.cluster.datastore.modification.MergeModification;
-import org.opendaylight.controller.cluster.datastore.modification.Modification;
-import org.opendaylight.controller.cluster.datastore.modification.WriteModification;
-import org.opendaylight.controller.cluster.entityownership.messages.CandidateAdded;
-import org.opendaylight.controller.cluster.entityownership.messages.CandidateRemoved;
-import org.opendaylight.controller.cluster.entityownership.messages.RegisterCandidateLocal;
-import org.opendaylight.controller.cluster.entityownership.messages.RegisterListenerLocal;
-import org.opendaylight.controller.cluster.entityownership.messages.RemoveAllCandidates;
-import org.opendaylight.controller.cluster.entityownership.messages.SelectOwner;
-import org.opendaylight.controller.cluster.entityownership.messages.UnregisterCandidateLocal;
-import org.opendaylight.controller.cluster.entityownership.messages.UnregisterListenerLocal;
-import org.opendaylight.controller.cluster.entityownership.selectionstrategy.EntityOwnerSelectionStrategy;
-import org.opendaylight.controller.cluster.entityownership.selectionstrategy.EntityOwnerSelectionStrategyConfig;
-import org.opendaylight.controller.cluster.raft.RaftState;
-import org.opendaylight.controller.cluster.raft.VotingState;
-import org.opendaylight.mdsal.eos.dom.api.DOMEntity;
-import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
-import org.opendaylight.yangtools.yang.data.api.schema.DataContainerChild;
-import org.opendaylight.yangtools.yang.data.api.schema.MapEntryNode;
-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.
- *
- * @author Thomas Pantelis
- */
-class EntityOwnershipShard extends Shard {
- private final MemberName localMemberName;
- private final EntityOwnershipShardCommitCoordinator commitCoordinator;
- private final EntityOwnershipListenerSupport listenerSupport;
- private final Set<MemberName> downPeerMemberNames = new HashSet<>();
- private final EntityOwnerSelectionStrategyConfig strategyConfig;
- private final Map<YangInstanceIdentifier, Cancellable> entityToScheduledOwnershipTask = new HashMap<>();
- private final EntityOwnershipStatistics entityOwnershipStatistics;
- private boolean removeAllInitialCandidates = true;
-
- protected EntityOwnershipShard(final Builder builder) {
- super(builder);
- this.localMemberName = builder.localMemberName;
- this.commitCoordinator = new EntityOwnershipShardCommitCoordinator(builder.localMemberName, LOG);
- this.listenerSupport = new EntityOwnershipListenerSupport(getContext(), persistenceId());
- this.strategyConfig = builder.ownerSelectionStrategyConfig;
- this.entityOwnershipStatistics = new EntityOwnershipStatistics();
- this.entityOwnershipStatistics.init(getDataStore());
- }
-
- private static DatastoreContext noPersistenceDatastoreContext(final DatastoreContext datastoreContext) {
- return DatastoreContext.newBuilderFrom(datastoreContext).persistent(false).build();
- }
-
- @Override
- protected void onDatastoreContext(final DatastoreContext context) {
- super.onDatastoreContext(noPersistenceDatastoreContext(context));
- }
-
- @Override
- protected void onRecoveryComplete() {
- super.onRecoveryComplete();
-
- new CandidateListChangeListener(getSelf(), persistenceId()).init(getDataStore());
- new EntityOwnerChangeListener(localMemberName, listenerSupport).init(getDataStore());
- }
-
- @Override
- public void handleNonRaftCommand(final Object message) {
- if (message instanceof RegisterCandidateLocal) {
- onRegisterCandidateLocal((RegisterCandidateLocal) message);
- } else if (message instanceof UnregisterCandidateLocal) {
- onUnregisterCandidateLocal((UnregisterCandidateLocal) message);
- } else if (message instanceof CandidateAdded) {
- onCandidateAdded((CandidateAdded) message);
- } else if (message instanceof CandidateRemoved) {
- onCandidateRemoved((CandidateRemoved) message);
- } else if (message instanceof PeerDown) {
- onPeerDown((PeerDown) message);
- } else if (message instanceof PeerUp) {
- onPeerUp((PeerUp) message);
- } else if (message instanceof RegisterListenerLocal) {
- onRegisterListenerLocal((RegisterListenerLocal) message);
- } else if (message instanceof UnregisterListenerLocal) {
- onUnregisterListenerLocal((UnregisterListenerLocal) message);
- } else if (message instanceof SelectOwner) {
- onSelectOwner((SelectOwner) message);
- } else if (message instanceof RemoveAllCandidates) {
- onRemoveAllCandidates((RemoveAllCandidates) message);
- } else if (!commitCoordinator.handleMessage(message, this)) {
- super.handleNonRaftCommand(message);
- }
- }
-
- private void onRemoveAllCandidates(final RemoveAllCandidates message) {
- LOG.debug("{}: onRemoveAllCandidates: {}", persistenceId(), message);
-
- removeCandidateFromEntities(message.getMemberName());
- }
-
- private void onSelectOwner(final SelectOwner selectOwner) {
- LOG.debug("{}: onSelectOwner: {}", persistenceId(), selectOwner);
-
- String currentOwner = getCurrentOwner(selectOwner.getEntityPath());
- if (Strings.isNullOrEmpty(currentOwner)) {
- writeNewOwner(selectOwner.getEntityPath(), newOwner(currentOwner, 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(final RegisterCandidateLocal registerCandidate) {
- LOG.debug("{}: onRegisterCandidateLocal: {}", persistenceId(), registerCandidate);
-
- NormalizedNode entityOwners = entityOwnersWithCandidate(registerCandidate.getEntity().getType(),
- registerCandidate.getEntity().getIdentifier(), localMemberName.getName());
- commitCoordinator.commitModification(new MergeModification(ENTITY_OWNERS_PATH, entityOwners), this);
-
- getSender().tell(SuccessReply.INSTANCE, getSelf());
- }
-
- private void onUnregisterCandidateLocal(final UnregisterCandidateLocal unregisterCandidate) {
- LOG.debug("{}: onUnregisterCandidateLocal: {}", persistenceId(), unregisterCandidate);
-
- DOMEntity entity = unregisterCandidate.getEntity();
- YangInstanceIdentifier candidatePath = candidatePath(entity.getType(), entity.getIdentifier(),
- localMemberName.getName());
- commitCoordinator.commitModification(new DeleteModification(candidatePath), this);
-
- getSender().tell(SuccessReply.INSTANCE, getSelf());
- }
-
- private void onRegisterListenerLocal(final RegisterListenerLocal registerListener) {
- LOG.debug("{}: onRegisterListenerLocal: {}", persistenceId(), registerListener);
-
- listenerSupport.addEntityOwnershipListener(registerListener.getEntityType(), registerListener.getListener());
-
- getSender().tell(SuccessReply.INSTANCE, getSelf());
-
- searchForEntities((entityTypeNode, entityNode) -> {
- String entityType = entityTypeNode.findChildByArg(ENTITY_TYPE_NODE_ID)
- .map(child -> child.body().toString())
- .orElse(null);
- if (registerListener.getEntityType().equals(entityType)) {
- final boolean hasOwner;
- final boolean isOwner;
-
- Optional<DataContainerChild> possibleOwner = entityNode.findChildByArg(ENTITY_OWNER_NODE_ID);
- if (possibleOwner.isPresent()) {
- isOwner = localMemberName.getName().equals(possibleOwner.get().body().toString());
- hasOwner = true;
- } else {
- isOwner = false;
- hasOwner = false;
- }
-
- DOMEntity entity = new DOMEntity(entityType,
- (YangInstanceIdentifier) entityNode.findChildByArg(ENTITY_ID_NODE_ID).get().body());
-
- listenerSupport.notifyEntityOwnershipListener(entity, false, isOwner, hasOwner,
- registerListener.getListener());
- }
- });
- }
-
- private void onUnregisterListenerLocal(final 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) {
- possiblyRemoveAllInitialCandidates(leader);
-
- 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());
- }
- }
- }
-
- void possiblyRemoveAllInitialCandidates(final ActorSelection leader) {
- // The following handles removing all candidates on startup when re-joining with a remote leader. When a
- // follower is detected as down, the leader will re-assign new owners to entities that were owned by the
- // down member but doesn't remove the down member as a candidate, as the down node may actually be isolated
- // and still running. Therefore on startup we send an initial message to the remote leader to remove any
- // potential stale candidates we had previously registered, as it's possible a candidate may not be
- // registered by a client in the new incarnation. We have to send the RemoveAllCandidates message prior to any
- // pending registrations.
- if (removeAllInitialCandidates && leader != null) {
- removeAllInitialCandidates = false;
- if (!isLeader()) {
- LOG.debug("{} - got new leader {} on startup - sending RemoveAllCandidates", persistenceId(), leader);
-
- leader.tell(new RemoveAllCandidates(localMemberName), ActorRef.noSender());
- }
- }
- }
-
- boolean hasLeader() {
- return getLeader() != null && (!isLeader() || isLeaderActive());
- }
-
- /**
- * Determine if we are in jeopardy based on observed RAFT state.
- */
- private static boolean inJeopardy(final RaftState state) {
- switch (state) {
- case Candidate:
- case Follower:
- case Leader:
- case PreLeader:
- return false;
- case IsolatedLeader:
- return true;
- default:
- throw new IllegalStateException("Unsupported RAFT state " + state);
- }
- }
-
- private void notifyAllListeners() {
- searchForEntities((entityTypeNode, entityNode) -> {
- Optional<DataContainerChild> possibleType = entityTypeNode.findChildByArg(ENTITY_TYPE_NODE_ID);
- if (possibleType.isPresent()) {
- final boolean hasOwner;
- final boolean isOwner;
-
- Optional<DataContainerChild> possibleOwner = entityNode.findChildByArg(ENTITY_OWNER_NODE_ID);
- if (possibleOwner.isPresent()) {
- isOwner = localMemberName.getName().equals(possibleOwner.get().body().toString());
- hasOwner = true;
- } else {
- isOwner = false;
- hasOwner = false;
- }
-
- DOMEntity entity = new DOMEntity(possibleType.get().body().toString(),
- (YangInstanceIdentifier) entityNode.findChildByArg(ENTITY_ID_NODE_ID).get().body());
-
- listenerSupport.notifyEntityOwnershipListeners(entity, isOwner, isOwner, hasOwner);
- }
- });
- }
-
- @Override
- protected void onStateChanged() {
- boolean isLeader = isLeader();
- LOG.debug("{}: onStateChanged: isLeader: {}, hasLeader: {}", persistenceId(), isLeader, hasLeader());
-
- // Examine current RAFT state to see if we are in jeopardy, potentially notifying all listeners
- final boolean inJeopardy = inJeopardy(getRaftState());
- final boolean wasInJeopardy = listenerSupport.setInJeopardy(inJeopardy);
- if (inJeopardy != wasInJeopardy) {
- LOG.debug("{}: {} jeopardy state, notifying all listeners", persistenceId(),
- inJeopardy ? "entered" : "left");
- notifyAllListeners();
- }
-
- commitCoordinator.onStateChanged(this, isLeader);
-
- super.onStateChanged();
- }
-
- @Override
- protected void onLeaderChanged(final String oldLeader, final String newLeader) {
- boolean isLeader = isLeader();
- LOG.debug("{}: onLeaderChanged: oldLeader: {}, newLeader: {}, isLeader: {}", persistenceId(), oldLeader,
- newLeader, isLeader);
-
- if (isLeader) {
-
- // Re-initialize the downPeerMemberNames from the current akka Cluster state. The previous leader, if any,
- // is most likely down however it's possible we haven't received the PeerDown message yet.
- initializeDownPeerMemberNamesFromClusterState();
-
- // Clear all existing strategies so that they get re-created when we call createStrategy again
- // This allows the strategies to be re-initialized with existing statistics maintained by
- // EntityOwnershipStatistics
- strategyConfig.clearStrategies();
-
- // Re-assign owners for all members that are known to be down. In a cluster which has greater than
- // 3 nodes it is possible for some node beside the leader being down when the leadership transitions
- // it makes sense to use this event to re-assign owners for those downed nodes.
- Set<String> ownedBy = new HashSet<>(downPeerMemberNames.size() + 1);
- for (MemberName downPeerName : downPeerMemberNames) {
- ownedBy.add(downPeerName.getName());
- }
-
- // Also try to assign owners for entities that have no current owner. See explanation in onPeerUp.
- ownedBy.add("");
- selectNewOwnerForEntitiesOwnedBy(ownedBy);
- } else {
- // The leader changed - notify the coordinator to check if pending modifications need to be sent.
- // While onStateChanged also does this, this method handles the case where the shard hears from a
- // leader and stays in the follower state. In that case no behavior state change occurs.
- commitCoordinator.onStateChanged(this, isLeader);
- }
-
- super.onLeaderChanged(oldLeader, newLeader);
- }
-
- @Override
- protected void onVotingStateChangeComplete() {
- // Re-evaluate ownership for all entities - if a member changed from voting to non-voting it should lose
- // ownership and vice versa it now is a candidate to become owner.
- final List<Modification> modifications = new ArrayList<>();
- searchForEntities((entityTypeNode, entityNode) -> {
- YangInstanceIdentifier entityPath = YangInstanceIdentifier.builder(ENTITY_TYPES_PATH)
- .node(entityTypeNode.getIdentifier()).node(ENTITY_NODE_ID).node(entityNode.getIdentifier())
- .node(ENTITY_OWNER_NODE_ID).build();
-
- Optional<String> possibleOwner =
- entityNode.findChildByArg(ENTITY_OWNER_NODE_ID).map(node -> node.body().toString());
- String newOwner = newOwner(possibleOwner.orElse(null), getCandidateNames(entityNode),
- getEntityOwnerElectionStrategy(entityPath));
-
- if (!newOwner.equals(possibleOwner.orElse(""))) {
- modifications.add(new WriteModification(entityPath,
- ImmutableNodes.leafNode(ENTITY_OWNER_NODE_ID, newOwner)));
- }
- });
-
- commitCoordinator.commitModifications(modifications, this);
- }
-
- private void initializeDownPeerMemberNamesFromClusterState() {
- Optional<Cluster> cluster = getRaftActorContext().getCluster();
- if (!cluster.isPresent()) {
- return;
- }
-
- CurrentClusterState state = cluster.get().state();
- Set<Member> unreachable = state.getUnreachable();
-
- LOG.debug(
- "{}: initializeDownPeerMemberNamesFromClusterState - current downPeerMemberNames: {}, unreachable: {}",
- persistenceId(), downPeerMemberNames, unreachable);
-
- downPeerMemberNames.clear();
- for (Member m: unreachable) {
- downPeerMemberNames.add(MemberName.forName(m.getRoles().iterator().next()));
- }
-
- for (Member m: state.getMembers()) {
- if (m.status() != MemberStatus.up() && m.status() != MemberStatus.weaklyUp()) {
- LOG.debug("{}: Adding down member with status {}", persistenceId(), m.status());
- downPeerMemberNames.add(MemberName.forName(m.getRoles().iterator().next()));
- }
- }
-
- LOG.debug("{}: new downPeerMemberNames: {}", persistenceId(), downPeerMemberNames);
- }
-
- private void onCandidateRemoved(final CandidateRemoved message) {
- LOG.debug("{}: onCandidateRemoved: {}", persistenceId(), message);
-
- if (isLeader()) {
- String currentOwner = getCurrentOwner(message.getEntityPath());
- writeNewOwner(message.getEntityPath(),
- newOwner(currentOwner, message.getRemainingCandidates(),
- getEntityOwnerElectionStrategy(message.getEntityPath())));
- }
- }
-
- private EntityOwnerSelectionStrategy getEntityOwnerElectionStrategy(final YangInstanceIdentifier entityPath) {
- final String entityType = EntityOwnersModel.entityTypeFromEntityPath(entityPath);
- return strategyConfig.createStrategy(entityType, entityOwnershipStatistics.byEntityType(entityType));
- }
-
- private void onCandidateAdded(final 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(MemberName.forName(message.getNewCandidate()));
-
- final String currentOwner = getCurrentOwner(message.getEntityPath());
- final EntityOwnerSelectionStrategy strategy = getEntityOwnerElectionStrategy(message.getEntityPath());
-
- // Available members is all the known peers - the number of peers that are down + self
- // So if there are 2 peers and 1 is down then availableMembers will be 2
- final int availableMembers = getRaftActorContext().getPeerIds().size() - downPeerMemberNames.size() + 1;
-
- LOG.debug("{}: Using strategy {} to select owner, currentOwner = {}", persistenceId(), strategy, currentOwner);
-
- if (strategy.getSelectionDelayInMillis() == 0L) {
- writeNewOwner(message.getEntityPath(), newOwner(currentOwner, message.getAllCandidates(),
- strategy));
- } else if (message.getAllCandidates().size() == availableMembers) {
- LOG.debug("{}: Received the maximum candidates requests : {} writing new owner",
- persistenceId(), availableMembers);
- cancelOwnerSelectionTask(message.getEntityPath());
- writeNewOwner(message.getEntityPath(), newOwner(currentOwner, message.getAllCandidates(),
- strategy));
- } else {
- scheduleOwnerSelection(message.getEntityPath(), message.getAllCandidates(), strategy);
- }
- }
-
- private void onPeerDown(final PeerDown peerDown) {
- LOG.info("{}: onPeerDown: {}", persistenceId(), peerDown);
-
- MemberName downMemberName = peerDown.getMemberName();
- if (downPeerMemberNames.add(downMemberName) && isLeader()) {
- // Select new owners for entities owned by the down peer and which have other candidates. For an entity for
- // which the down peer is the only candidate, we leave it as the owner and don't clear it. This is done to
- // handle the case where the peer member process is actually still running but the node is partitioned.
- // When the partition is healed, the peer just remains as the owner. If the peer process actually restarted,
- // it will first remove all its candidates on startup. If another candidate is registered during the time
- // the peer is down, the new candidate will be selected as the new owner.
-
- selectNewOwnerForEntitiesOwnedBy(ImmutableSet.of(downMemberName.getName()));
- }
- }
-
- private void selectNewOwnerForEntitiesOwnedBy(final Set<String> ownedBy) {
- final List<Modification> modifications = new ArrayList<>();
- searchForEntitiesOwnedBy(ownedBy, (entityTypeNode, entityNode) -> {
- YangInstanceIdentifier entityPath = YangInstanceIdentifier.builder(ENTITY_TYPES_PATH)
- .node(entityTypeNode.getIdentifier()).node(ENTITY_NODE_ID).node(entityNode.getIdentifier())
- .node(ENTITY_OWNER_NODE_ID).build();
- String newOwner = newOwner(getCurrentOwner(entityPath), getCandidateNames(entityNode),
- getEntityOwnerElectionStrategy(entityPath));
-
- if (!newOwner.isEmpty()) {
- LOG.debug("{}: Found entity {}, writing new owner {}", persistenceId(), entityPath, newOwner);
-
- modifications.add(new WriteModification(entityPath,
- ImmutableNodes.leafNode(ENTITY_OWNER_NODE_ID, newOwner)));
-
- } else {
- LOG.debug("{}: Found entity {} but no other candidates - not clearing owner", persistenceId(),
- entityPath);
- }
- });
-
- commitCoordinator.commitModifications(modifications, this);
- }
-
- private void onPeerUp(final PeerUp peerUp) {
- LOG.debug("{}: onPeerUp: {}", persistenceId(), peerUp);
-
- downPeerMemberNames.remove(peerUp.getMemberName());
-
- // Notify the coordinator to check if pending modifications need to be sent. We do this here
- // to handle the case where the leader's peer address isn't known yet when a prior state or
- // leader change occurred.
- commitCoordinator.onStateChanged(this, isLeader());
-
- if (isLeader()) {
- // Try to assign owners for entities that have no current owner. It's possible the peer that is now up
- // had previously registered as a candidate and was the only candidate but the owner write tx couldn't be
- // committed due to a leader change. Eg, the leader is able to successfully commit the candidate add tx but
- // becomes isolated before it can commit the owner change and switches to follower. The majority partition
- // with a new leader has the candidate but the entity has no owner. When the partition is healed and the
- // previously isolated leader reconnects, we'll receive onPeerUp and, if there's still no owner, the
- // previous leader will gain ownership.
- selectNewOwnerForEntitiesOwnedBy(ImmutableSet.of(""));
- }
- }
-
- private static Collection<String> getCandidateNames(final MapEntryNode entity) {
- return entity.findChildByArg(CANDIDATE_NODE_ID).map(child -> {
- Collection<MapEntryNode> candidates = ((MapNode) child).body();
- Collection<String> candidateNames = new ArrayList<>(candidates.size());
- for (MapEntryNode candidate: candidates) {
- candidateNames.add(candidate.findChildByArg(CANDIDATE_NAME_NODE_ID).get().body().toString());
- }
- return candidateNames;
- }).orElse(ImmutableList.of());
- }
-
- private void searchForEntitiesOwnedBy(final Set<String> ownedBy, final EntityWalker walker) {
- LOG.debug("{}: Searching for entities owned by {}", persistenceId(), ownedBy);
-
- searchForEntities((entityTypeNode, entityNode) -> {
- String currentOwner = entityNode.findChildByArg(ENTITY_OWNER_NODE_ID)
- .map(child -> child.body().toString())
- .orElse("");
- if (ownedBy.contains(currentOwner)) {
- walker.onEntity(entityTypeNode, entityNode);
- }
- });
- }
-
- private void removeCandidateFromEntities(final MemberName member) {
- final List<Modification> modifications = new ArrayList<>();
- searchForEntities((entityTypeNode, entityNode) -> {
- if (hasCandidate(entityNode, member)) {
- YangInstanceIdentifier entityId = (YangInstanceIdentifier) entityNode.getIdentifier()
- .getValue(ENTITY_ID_QNAME);
- YangInstanceIdentifier candidatePath = candidatePath(entityTypeNode.getIdentifier()
- .getValue(ENTITY_TYPE_QNAME).toString(), entityId, member.getName());
-
- LOG.info("{}: Found entity {}, removing candidate {}, path {}", persistenceId(), entityId,
- member, candidatePath);
-
- modifications.add(new DeleteModification(candidatePath));
- }
- });
-
- commitCoordinator.commitModifications(modifications, this);
- }
-
- private static boolean hasCandidate(final MapEntryNode entity, final MemberName candidateName) {
- return entity.findChildByArg(CANDIDATE_NODE_ID)
- .flatMap(child -> ((MapNode)child).findChildByArg(candidateNodeKey(candidateName.getName())))
- .isPresent();
- }
-
- private void searchForEntities(final EntityWalker walker) {
- Optional<NormalizedNode> possibleEntityTypes = getDataStore().readNode(ENTITY_TYPES_PATH);
- if (!possibleEntityTypes.isPresent()) {
- return;
- }
-
- for (MapEntryNode entityType : ((MapNode) possibleEntityTypes.get()).body()) {
- Optional<DataContainerChild> possibleEntities = entityType.findChildByArg(ENTITY_NODE_ID);
- if (!possibleEntities.isPresent()) {
- // shouldn't happen but handle anyway
- continue;
- }
-
- for (MapEntryNode entity: ((MapNode) possibleEntities.get()).body()) {
- walker.onEntity(entityType, entity);
- }
- }
- }
-
- private void writeNewOwner(final YangInstanceIdentifier entityPath, final String newOwner) {
- LOG.debug("{}: Writing new owner {} for entity {}", persistenceId(), newOwner, entityPath);
-
- commitCoordinator.commitModification(new WriteModification(entityPath.node(ENTITY_OWNER_QNAME),
- ImmutableNodes.leafNode(ENTITY_OWNER_NODE_ID, newOwner)), this);
- }
-
- /**
- * Schedule a new owner selection job. Cancelling any outstanding job if it has not been cancelled.
- */
- private void scheduleOwnerSelection(final YangInstanceIdentifier entityPath, final Collection<String> allCandidates,
- final EntityOwnerSelectionStrategy strategy) {
- cancelOwnerSelectionTask(entityPath);
-
- LOG.debug("{}: Scheduling owner selection after {} ms", persistenceId(), strategy.getSelectionDelayInMillis());
-
- final Cancellable 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 void cancelOwnerSelectionTask(final YangInstanceIdentifier entityPath) {
- final Cancellable lastScheduledTask = entityToScheduledOwnershipTask.get(entityPath);
- if (lastScheduledTask != null && !lastScheduledTask.isCancelled()) {
- lastScheduledTask.cancel();
- }
- }
-
- private String newOwner(final String currentOwner, final Collection<String> candidates,
- final EntityOwnerSelectionStrategy ownerSelectionStrategy) {
- Collection<String> viableCandidates = getViableCandidates(candidates);
- if (viableCandidates.isEmpty()) {
- return "";
- }
- return ownerSelectionStrategy.newOwner(currentOwner, viableCandidates);
- }
-
- private Collection<String> getViableCandidates(final Collection<String> candidates) {
- Map<MemberName, VotingState> memberToVotingState = new HashMap<>();
- getRaftActorContext().getPeers().forEach(peerInfo -> memberToVotingState.put(
- ShardIdentifier.fromShardIdString(peerInfo.getId()).getMemberName(), peerInfo.getVotingState()));
-
- Collection<String> viableCandidates = new ArrayList<>();
-
- for (String candidate : candidates) {
- MemberName memberName = MemberName.forName(candidate);
- if (memberToVotingState.get(memberName) != VotingState.NON_VOTING
- && !downPeerMemberNames.contains(memberName)) {
- viableCandidates.add(candidate);
- }
- }
- return viableCandidates;
- }
-
- private String getCurrentOwner(final YangInstanceIdentifier entityId) {
- return getDataStore().readNode(entityId.node(ENTITY_OWNER_QNAME))
- .map(owner -> owner.body().toString())
- .orElse(null);
- }
-
- @FunctionalInterface
- private interface EntityWalker {
- void onEntity(MapEntryNode entityTypeNode, MapEntryNode entityNode);
- }
-
- public static Builder newBuilder() {
- return new Builder();
- }
-
- static class Builder extends Shard.AbstractBuilder<Builder, EntityOwnershipShard> {
- private MemberName localMemberName;
- private EntityOwnerSelectionStrategyConfig ownerSelectionStrategyConfig;
-
- protected Builder() {
- super(EntityOwnershipShard.class);
- }
-
- Builder localMemberName(final MemberName newLocalMemberName) {
- checkSealed();
- this.localMemberName = newLocalMemberName;
- return this;
- }
-
- Builder ownerSelectionStrategyConfig(final EntityOwnerSelectionStrategyConfig newOwnerSelectionStrategyConfig) {
- checkSealed();
- this.ownerSelectionStrategyConfig = newOwnerSelectionStrategyConfig;
- return this;
- }
-
- @Override
- protected void verify() {
- super.verify();
- requireNonNull(localMemberName, "localMemberName should not be null");
- requireNonNull(ownerSelectionStrategyConfig, "ownerSelectionStrategyConfig should not be null");
- }
- }
-}