* This is to account for situations where a we know that a peer * exists but we do not know an address up-front. This may also be used in * situations where a known peer starts off in a different location and we * need to change it's address *
* Note that if the peerId does not match the list of peers passed to
* this actor during construction an IllegalStateException will be thrown.
*
* @param peerId
* @param peerAddress
*/
protected void setPeerAddress(String peerId, String peerAddress){
context.setPeerAddress(peerId, peerAddress);
}
/**
* The applyState method will be called by the RaftActor when some data
* needs to be applied to the actor's state
*
* @param clientActor A reference to the client who sent this message. This
* is the same reference that was passed to persistData
* by the derived actor. clientActor may be null when
* the RaftActor is behaving as a follower or during
* recovery.
* @param identifier The identifier of the persisted data. This is also
* the same identifier that was passed to persistData by
* the derived actor. identifier may be null when
* the RaftActor is behaving as a follower or during
* recovery
* @param data A piece of data that was persisted by the persistData call.
* This should NEVER be null.
*/
protected abstract void applyState(ActorRef clientActor, Identifier identifier, Object data);
/**
* Returns the RaftActorRecoveryCohort to participate in persistence recovery.
*/
@Nonnull
protected abstract RaftActorRecoveryCohort getRaftActorRecoveryCohort();
/**
* This method is called when recovery is complete.
*/
protected abstract void onRecoveryComplete();
/**
* Returns the RaftActorSnapshotCohort to participate in persistence recovery.
*/
@Nonnull
protected abstract RaftActorSnapshotCohort getRaftActorSnapshotCohort();
/**
* This method will be called by the RaftActor when the state of the
* RaftActor changes. The derived actor can then use methods like
* isLeader or getLeader to do something useful
*/
protected abstract void onStateChanged();
/**
* Notifier Actor for this RaftActor to notify when a role change happens
* @return ActorRef - ActorRef of the notifier or Optional.absent if none.
*/
protected abstract Optional
* The default implementation immediately runs the operation.
*
* @param operation the operation to run
*/
protected void pauseLeader(Runnable operation) {
operation.run();
}
protected void onLeaderChanged(String oldLeader, String newLeader) {
};
private String getLeaderAddress(){
if(isLeader()){
return getSelf().path().toString();
}
String leaderId = getLeaderId();
if (leaderId == null) {
return null;
}
String peerAddress = context.getPeerAddress(leaderId);
if(LOG.isDebugEnabled()) {
LOG.debug("{}: getLeaderAddress leaderId = {} peerAddress = {}",
persistenceId(), leaderId, peerAddress);
}
return peerAddress;
}
protected boolean hasFollowers(){
return getRaftActorContext().hasFollowers();
}
private void captureSnapshot() {
SnapshotManager snapshotManager = context.getSnapshotManager();
if (!snapshotManager.isCapturing()) {
final long idx = getCurrentBehavior().getReplicatedToAllIndex();
LOG.debug("Take a snapshot of current state. lastReplicatedLog is {} and replicatedToAllIndex is {}",
replicatedLog().last(), idx);
snapshotManager.capture(replicatedLog().last(), idx);
}
}
/**
* Switch this member to non-voting status. This is a no-op for all behaviors except when we are the leader,
* in which case we need to step down.
*/
void becomeNonVoting() {
if (isLeader()) {
initiateLeadershipTransfer(new RaftActorLeadershipTransferCohort.OnComplete() {
@Override
public void onSuccess(ActorRef raftActorRef) {
LOG.debug("{}: leader transfer succeeded after change to non-voting", persistenceId());
ensureFollowerState();
}
@Override
public void onFailure(ActorRef raftActorRef) {
LOG.debug("{}: leader transfer failed after change to non-voting", persistenceId());
ensureFollowerState();
}
private void ensureFollowerState() {
// Whether or not leadership transfer succeeded, we have to step down as leader and
// switch to Follower so ensure that.
if (getRaftState() != RaftState.Follower) {
initializeBehavior();
}
}
});
}
}
/**
* @deprecated Deprecated in favor of {@link org.opendaylight.controller.cluster.raft.base.messages.DeleteEntries}
* whose type for fromIndex is long instead of int. This class was kept for backwards
* compatibility with Helium.
*/
// Suppressing this warning as we can't set serialVersionUID to maintain backwards compatibility.
@SuppressWarnings("serial")
@Deprecated
static class DeleteEntries implements Serializable {
private final int fromIndex;
public DeleteEntries(int fromIndex) {
this.fromIndex = fromIndex;
}
public int getFromIndex() {
return fromIndex;
}
}
/**
* @deprecated Deprecated in favor of non-inner class {@link org.opendaylight.controller.cluster.raft.base.messages.UpdateElectionTerm}
* which has serialVersionUID set. This class was kept for backwards compatibility with Helium.
*/
// Suppressing this warning as we can't set serialVersionUID to maintain backwards compatibility.
@SuppressWarnings("serial")
@Deprecated
static class UpdateElectionTerm implements Serializable {
private final long currentTerm;
private final String votedFor;
public UpdateElectionTerm(long currentTerm, String votedFor) {
this.currentTerm = currentTerm;
this.votedFor = votedFor;
}
public long getCurrentTerm() {
return currentTerm;
}
public String getVotedFor() {
return votedFor;
}
}
/**
* A point-in-time capture of {@link RaftActorBehavior} state critical for transitioning between behaviors.
*/
private static abstract class BehaviorState implements Immutable {
@Nullable abstract RaftActorBehavior getBehavior();
@Nullable abstract String getLastValidLeaderId();
@Nullable abstract short getLeaderPayloadVersion();
}
/**
* A {@link BehaviorState} corresponding to non-null {@link RaftActorBehavior} state.
*/
private static final class SimpleBehaviorState extends BehaviorState {
private final RaftActorBehavior behavior;
private final String lastValidLeaderId;
private final short leaderPayloadVersion;
SimpleBehaviorState(final String lastValidLeaderId, final RaftActorBehavior behavior) {
this.lastValidLeaderId = lastValidLeaderId;
this.behavior = Preconditions.checkNotNull(behavior);
this.leaderPayloadVersion = behavior.getLeaderPayloadVersion();
}
@Override
RaftActorBehavior getBehavior() {
return behavior;
}
@Override
String getLastValidLeaderId() {
return lastValidLeaderId;
}
@Override
short getLeaderPayloadVersion() {
return leaderPayloadVersion;
}
}
/**
* Class tracking behavior-related information, which we need to keep around and pass across behavior switches.
* An instance is created for each RaftActor. It has two functions:
* - it keeps track of the last leader ID we have encountered since we have been created
* - it creates state capture needed to transition from one behavior to the next
*/
private static final class BehaviorStateTracker {
/**
* A {@link BehaviorState} corresponding to null {@link RaftActorBehavior} state. Since null behavior is only
* allowed before we receive the first message, we know the leader ID to be null.
*/
private static final BehaviorState NULL_BEHAVIOR_STATE = new BehaviorState() {
@Override
RaftActorBehavior getBehavior() {
return null;
}
@Override
String getLastValidLeaderId() {
return null;
}
@Override
short getLeaderPayloadVersion() {
return -1;
}
};
private String lastValidLeaderId;
BehaviorState capture(final RaftActorBehavior behavior) {
if (behavior == null) {
Verify.verify(lastValidLeaderId == null, "Null behavior with non-null last leader");
return NULL_BEHAVIOR_STATE;
}
final String leaderId = behavior.getLeaderId();
if (leaderId != null) {
lastValidLeaderId = leaderId;
}
return new SimpleBehaviorState(lastValidLeaderId, behavior);
}
}
}