* set currentTerm = T, convert to follower (§5.1)
*/
public abstract class AbstractRaftActorBehavior implements RaftActorBehavior {
-
- protected static final ElectionTimeout ELECTION_TIMEOUT = new ElectionTimeout();
-
/**
* Information about the RaftActor whose behavior this class represents
*/
*/
protected String leaderId = null;
+ private short leaderPayloadVersion = -1;
+
private long replicatedToAllIndex = -1;
private final String logName;
*
* @param sender The actor that sent this message
* @param appendEntries The AppendEntries message
- * @return
+ * @return a new behavior if it was changed or the current behavior
*/
protected abstract RaftActorBehavior handleAppendEntries(ActorRef sender,
AppendEntries appendEntries);
*
* @param sender
* @param appendEntries
- * @return
+ * @return a new behavior if it was changed or the current behavior
*/
protected RaftActorBehavior appendEntries(ActorRef sender,
AppendEntries appendEntries) {
sender.tell(
new AppendEntriesReply(context.getId(), currentTerm(), false,
- lastIndex(), lastTerm()), actor()
+ lastIndex(), lastTerm(), context.getPayloadVersion()), actor()
);
return this;
}
*
* @param sender The actor that sent this message
* @param appendEntriesReply The AppendEntriesReply message
- * @return
+ * @return a new behavior if it was changed or the current behavior
*/
protected abstract RaftActorBehavior handleAppendEntriesReply(ActorRef sender,
AppendEntriesReply appendEntriesReply);
*
* @param sender
* @param requestVote
- * @return
+ * @return a new behavior if it was changed or the current behavior
*/
protected RaftActorBehavior requestVote(ActorRef sender, RequestVote requestVote) {
LOG.debug("{}: In requestVote: {}", logName(), requestVote);
+ boolean grantVote = canGrantVote(requestVote);
+
+ if(grantVote) {
+ context.getTermInformation().updateAndPersist(requestVote.getTerm(), requestVote.getCandidateId());
+ }
+
+ RequestVoteReply reply = new RequestVoteReply(currentTerm(), grantVote);
+
+ LOG.debug("{}: requestVote returning: {}", logName(), reply);
+
+ sender.tell(reply, actor());
+
+ return this;
+ }
+
+ protected boolean canGrantVote(RequestVote requestVote){
boolean grantVote = false;
// Reply false if term < currentTerm (§5.1)
// If votedFor is null or candidateId, and candidate’s log is at
// least as up-to-date as receiver’s log, grant vote (§5.2, §5.4)
} else if (votedFor() == null || votedFor()
- .equals(requestVote.getCandidateId())) {
+ .equals(requestVote.getCandidateId())) {
boolean candidateLatest = false;
if (requestVote.getLastLogTerm() > lastTerm()) {
candidateLatest = true;
} else if ((requestVote.getLastLogTerm() == lastTerm())
- && requestVote.getLastLogIndex() >= lastIndex()) {
+ && requestVote.getLastLogIndex() >= lastIndex()) {
candidateLatest = true;
}
if (candidateLatest) {
grantVote = true;
- context.getTermInformation().updateAndPersist(requestVote.getTerm(),
- requestVote.getCandidateId());
}
}
-
- RequestVoteReply reply = new RequestVoteReply(currentTerm(), grantVote);
-
- LOG.debug("{}: requestVote returning: {}", logName(), reply);
-
- sender.tell(reply, actor());
-
- return this;
+ return grantVote;
}
/**
*
* @param sender The actor that sent this message
* @param requestVoteReply The RequestVoteReply message
- * @return
+ * @return a new behavior if it was changed or the current behavior
*/
protected abstract RaftActorBehavior handleRequestVoteReply(ActorRef sender,
RequestVoteReply requestVoteReply);
/**
- * Creates a random election duration
*
- * @return
+ * @return a random election duration
*/
protected FiniteDuration electionDuration() {
long variance = new Random().nextInt(context.getConfigParams().getElectionTimeVariance());
}
}
+ protected boolean canStartElection() {
+ return context.getRaftPolicy().automaticElectionsEnabled() && context.isVotingMember();
+ }
+
/**
* schedule a new election
*
- * @param interval
+ * @param interval the duration after which we should trigger a new election
*/
protected void scheduleElection(FiniteDuration interval) {
stopElection();
- // Schedule an election. When the scheduler triggers an ElectionTimeout
- // message is sent to itself
- electionCancel =
- context.getActorSystem().scheduler().scheduleOnce(interval,
- context.getActor(), ELECTION_TIMEOUT,
- context.getActorSystem().dispatcher(), context.getActor());
+ if(canStartElection()) {
+ // Schedule an election. When the scheduler triggers an ElectionTimeout message is sent to itself
+ electionCancel = context.getActorSystem().scheduler().scheduleOnce(interval, context.getActor(),
+ ElectionTimeout.INSTANCE, context.getActorSystem().dispatcher(), context.getActor());
+ }
}
/**
- * Get the current term
- * @return
+ * @return the current term
*/
protected long currentTerm() {
return context.getTermInformation().getCurrentTerm();
}
/**
- * Get the candidate for whom we voted in the current term
- * @return
+ * @return the candidate for whom we voted in the current term
*/
protected String votedFor() {
return context.getTermInformation().getVotedFor();
}
/**
- * Get the actor associated with this behavior
- * @return
+ * @return the actor associated with this behavior
*/
protected ActorRef actor() {
return context.getActor();
}
/**
- * Get the term from the last entry in the log
*
- * @return
+ * @return the term from the last entry in the log
*/
protected long lastTerm() {
return context.getReplicatedLog().lastTerm();
}
/**
- * Get the index from the last entry in the log
- *
- * @return
+ * @return the index from the last entry in the log
*/
protected long lastIndex() {
return context.getReplicatedLog().lastIndex();
}
/**
- * Find the client request tracker for a specific logIndex
- *
* @param logIndex
- * @return
+ * @return the client request tracker for the specified logIndex
*/
protected ClientRequestTracker findClientRequestTracker(long logIndex) {
return null;
}
/**
- * Find the client request tracker for a specific logIndex
- *
* @param logIndex
- * @return
+ * @return the client request tracker for the specified logIndex
*/
protected ClientRequestTracker removeClientRequestTracker(long logIndex) {
return null;
/**
- * Find the log index from the previous to last entry in the log
*
- * @return
+ * @return log index from the previous to last entry in the log
*/
protected long prevLogIndex(long index){
ReplicatedLogEntry prevEntry =
}
/**
- * Find the log term from the previous to last entry in the log
- * @return
+ * @return log term from the previous to last entry in the log
*/
protected long prevLogTerm(long index){
ReplicatedLogEntry prevEntry =
return leaderId;
}
- protected RaftActorBehavior switchBehavior(RaftActorBehavior behavior) {
- LOG.info("{} :- Switching from behavior {} to {}", logName(), this.state(), behavior.state());
+ @Override
+ public short getLeaderPayloadVersion() {
+ return leaderPayloadVersion;
+ }
+
+ public void setLeaderPayloadVersion(short leaderPayloadVersion) {
+ this.leaderPayloadVersion = leaderPayloadVersion;
+ }
+
+ @Override
+ public RaftActorBehavior switchBehavior(RaftActorBehavior behavior) {
+ return internalSwitchBehavior(behavior);
+ }
+
+ protected RaftActorBehavior internalSwitchBehavior(RaftState newState) {
+ if(context.getRaftPolicy().automaticElectionsEnabled()){
+ return internalSwitchBehavior(newState.createBehavior(context));
+ }
+ return this;
+ }
+
+ private RaftActorBehavior internalSwitchBehavior(RaftActorBehavior newBehavior) {
+ LOG.info("{} :- Switching from behavior {} to {}", logName(), this.state(), newBehavior.state());
try {
close();
} catch (Exception e) {
LOG.error("{}: Failed to close behavior : {}", logName(), this.state(), e);
}
-
- return behavior;
+ return newBehavior;
}
+
protected int getMajorityVoteCount(int numPeers) {
// Votes are required from a majority of the peers including self.
// The numMajority field therefore stores a calculated value
protected String getId(){
return context.getId();
}
-
}