import akka.actor.ActorRef;
import akka.actor.ActorSelection;
import akka.actor.PoisonPill;
+import akka.actor.Status;
import com.google.common.annotations.VisibleForTesting;
import com.google.common.base.Optional;
import com.google.common.base.Preconditions;
import org.opendaylight.controller.cluster.raft.client.messages.GetOnDemandRaftState;
import org.opendaylight.controller.cluster.raft.client.messages.OnDemandRaftState;
import org.opendaylight.controller.cluster.raft.client.messages.Shutdown;
+import org.opendaylight.controller.cluster.raft.messages.RequestLeadership;
import org.opendaylight.controller.cluster.raft.persisted.ApplyJournalEntries;
import org.opendaylight.controller.cluster.raft.persisted.NoopPayload;
import org.opendaylight.controller.cluster.raft.persisted.ServerConfigurationPayload;
private RaftActorServerConfigurationSupport serverConfigurationSupport;
- private RaftActorLeadershipTransferCohort leadershipTransferInProgress;
-
private boolean shuttingDown;
protected RaftActor(String id, Map<String, String> peerAddresses,
} else if (message instanceof Runnable) {
((Runnable)message).run();
} else if (message instanceof NoopPayload) {
- persistData(null, null, (NoopPayload)message, false);
+ persistData(null, null, (NoopPayload) message, false);
+ } else if (message instanceof RequestLeadership) {
+ onRequestLeadership((RequestLeadership) message);
} else if (!possiblyHandleBehaviorMessage(message)) {
handleNonRaftCommand(message);
}
}
+ private void onRequestLeadership(final RequestLeadership message) {
+ LOG.debug("{}: onRequestLeadership {}", persistenceId(), message);
+ if (!isLeader()) {
+ // non-leader cannot satisfy leadership request
+ LOG.warn("{}: onRequestLeadership {} was sent to non-leader."
+ + " Current behavior: {}. Sending failure response",
+ persistenceId(), getCurrentBehavior().state());
+ message.getReplyTo().tell(new LeadershipTransferFailedException("Cannot transfer leader to "
+ + message.getRequestedFollowerId()
+ + ". RequestLeadership message was sent to non-leader " + persistenceId()), getSelf());
+ return;
+ }
+
+ final String requestedFollowerId = message.getRequestedFollowerId();
+ final ActorRef replyTo = message.getReplyTo();
+ initiateLeadershipTransfer(new RaftActorLeadershipTransferCohort.OnComplete() {
+ @Override
+ public void onSuccess(final ActorRef raftActorRef) {
+ // sanity check
+ if (!requestedFollowerId.equals(getLeaderId())) {
+ onFailure(raftActorRef);
+ }
+
+ LOG.debug("{}: Leadership transferred successfully to {}", persistenceId(), requestedFollowerId);
+ replyTo.tell(new Status.Success(null), getSelf());
+ }
+
+ @Override
+ public void onFailure(final ActorRef raftActorRef) {
+ LOG.debug("{}: LeadershipTransfer request from {} failed", persistenceId(), requestedFollowerId);
+ replyTo.tell(new Status.Failure(
+ new LeadershipTransferFailedException(
+ "Failed to transfer leadership to " + requestedFollowerId
+ + ". Follower is not ready to become leader")),
+ getSelf());
+ }
+ }, message.getRequestedFollowerId(), RaftActorLeadershipTransferCohort.USE_DEFAULT_LEADER_TIMEOUT);
+ }
+
private boolean possiblyHandleBehaviorMessage(final Object message) {
final RaftActorBehavior currentBehavior = getCurrentBehavior();
final BehaviorState state = behaviorStateTracker.capture(currentBehavior);
return false;
}
- private void initiateLeadershipTransfer(final RaftActorLeadershipTransferCohort.OnComplete onComplete) {
+ private void initiateLeadershipTransfer(final RaftActorLeadershipTransferCohort.OnComplete onComplete,
+ @Nullable final String followerId, long newLeaderTimeoutInMillis) {
LOG.debug("{}: Initiating leader transfer", persistenceId());
+ RaftActorLeadershipTransferCohort leadershipTransferInProgress = context.getRaftActorLeadershipTransferCohort();
if (leadershipTransferInProgress == null) {
- leadershipTransferInProgress = new RaftActorLeadershipTransferCohort(this);
+ leadershipTransferInProgress = new RaftActorLeadershipTransferCohort(this, followerId);
+ leadershipTransferInProgress.setNewLeaderTimeoutInMillis(newLeaderTimeoutInMillis);
leadershipTransferInProgress.addOnComplete(new RaftActorLeadershipTransferCohort.OnComplete() {
@Override
public void onSuccess(ActorRef raftActorRef) {
- leadershipTransferInProgress = null;
+ context.setRaftActorLeadershipTransferCohort(null);
}
@Override
public void onFailure(ActorRef raftActorRef) {
- leadershipTransferInProgress = null;
+ context.setRaftActorLeadershipTransferCohort(null);
}
});
leadershipTransferInProgress.addOnComplete(onComplete);
+
+ context.setRaftActorLeadershipTransferCohort(leadershipTransferInProgress);
leadershipTransferInProgress.init();
+
} else {
LOG.debug("{}: prior leader transfer in progress - adding callback", persistenceId());
leadershipTransferInProgress.addOnComplete(onComplete);
shuttingDown = true;
final RaftActorBehavior currentBehavior = context.getCurrentBehavior();
- if (currentBehavior.state() != RaftState.Leader) {
- // For non-leaders shutdown is a no-op
- self().tell(PoisonPill.getInstance(), self());
- return;
+ switch (currentBehavior.state()) {
+ case Leader:
+ case PreLeader:
+ // Fall-through to more work
+ break;
+ default:
+ // For non-leaders shutdown is a no-op
+ self().tell(PoisonPill.getInstance(), self());
+ return;
}
if (context.hasFollowers()) {
LOG.debug("{}: leader transfer failed - sending PoisonPill", persistenceId());
raftActorRef.tell(PoisonPill.getInstance(), raftActorRef);
}
- });
+ }, null, TimeUnit.MILLISECONDS.convert(2, TimeUnit.SECONDS));
} else {
pauseLeader(new TimedRunnable(context.getConfigParams().getElectionTimeOutInterval(), this) {
@Override
}
final RaftActorBehavior currentBehavior = context.getCurrentBehavior();
- OnDemandRaftState.Builder builder = OnDemandRaftState.builder()
+ OnDemandRaftState.AbstractBuilder<?> builder = newOnDemandRaftStateBuilder()
.commitIndex(context.getCommitIndex())
.currentTerm(context.getTermInformation().getCurrentTerm())
.inMemoryJournalDataSize(replicatedLog().dataSize())
}
+ protected OnDemandRaftState.AbstractBuilder<?> newOnDemandRaftStateBuilder() {
+ return OnDemandRaftState.builder();
+ }
+
private void handleBehaviorChange(BehaviorState oldBehaviorState, RaftActorBehavior currentBehavior) {
RaftActorBehavior oldBehavior = oldBehaviorState.getBehavior();
onLeaderChanged(lastValidLeaderId, currentBehavior.getLeaderId());
+ RaftActorLeadershipTransferCohort leadershipTransferInProgress =
+ context.getRaftActorLeadershipTransferCohort();
if (leadershipTransferInProgress != null) {
leadershipTransferInProgress.onNewLeader(currentBehavior.getLeaderId());
}
&& !shuttingDown && !isLeadershipTransferInProgress();
}
- private boolean isLeadershipTransferInProgress() {
+ protected boolean isLeadershipTransferInProgress() {
+ RaftActorLeadershipTransferCohort leadershipTransferInProgress = context.getRaftActorLeadershipTransferCohort();
return leadershipTransferInProgress != null && leadershipTransferInProgress.isTransferring();
}
operation.run();
}
+ /**
+ * This method is invoked when the actions hooked to the leader becoming paused failed to execute and the leader
+ * should resume normal operations.
+ *
+ * <p>
+ * Note this method can be invoked even before the operation supplied to {@link #pauseLeader(Runnable)} is invoked.
+ */
+ protected void unpauseLeader() {
+
+ }
+
protected void onLeaderChanged(String oldLeader, String newLeader) {
}
initializeBehavior();
}
}
- });
+ }, null, RaftActorLeadershipTransferCohort.USE_DEFAULT_LEADER_TIMEOUT);
}
}