Re: [PR] KAFKA-17642: PreVote response handling and ProspectiveState [kafka]

[via GitHub]

ahuang98 commented on code in PR #18240:
URL: https://github.com/apache/kafka/pull/18240#discussion_r1900583739


##########
raft/src/main/java/org/apache/kafka/raft/QuorumState.java:
##########
@@ -529,26 +592,54 @@ public void transitionToFollower(int epoch, int leaderId, 
Endpoints endpoints) {
         );
     }
 
-    public void transitionToCandidate() {
+    /**
+     * Transition to the "prospective" state. This means the replica 
experienced a fetch/election timeout or
+     * loss of election as candidate. Note, if the replica is transitioning 
from prospective to add voted state
+     * and there is no epoch change, it takes the route of 
prospectiveAddVotedState instead.
+     */
+    public void transitionToProspective() {
         if (isObserver()) {
             throw new IllegalStateException(
                 String.format(
-                    "Cannot transition to Candidate since the local id (%s) 
and directory id (%s) " +
+                    "Cannot transition to Prospective since the local id (%s) 
and directory id (%s) " +
                     "is not one of the voters %s",
                     localId,
                     localDirectoryId,
                     partitionState.lastVoterSet()
                 )
             );
-        } else if (isLeader()) {
-            throw new IllegalStateException("Cannot transition to Candidate 
since the local broker.id=" + localId +
-                " since this node is already a Leader with state " + state);
+        } else if (isLeader() || isProspective()) {
+            throw new IllegalStateException("Cannot transition to Prospective 
since the local broker.id=" + localId +
+                " is state " + state);
         }
 
         int retries = isCandidate() ? candidateStateOrThrow().retries() + 1 : 
1;
+
+        durableTransitionTo(

Review Comment:
   🧠 



##########
raft/src/main/java/org/apache/kafka/raft/QuorumState.java:
##########
@@ -529,26 +592,54 @@ public void transitionToFollower(int epoch, int leaderId, 
Endpoints endpoints) {
         );
     }
 
-    public void transitionToCandidate() {
+    /**
+     * Transition to the "prospective" state. This means the replica 
experienced a fetch/election timeout or
+     * loss of election as candidate. Note, if the replica is transitioning 
from prospective to add voted state
+     * and there is no epoch change, it takes the route of 
prospectiveAddVotedState instead.
+     */
+    public void transitionToProspective() {
         if (isObserver()) {
             throw new IllegalStateException(
                 String.format(
-                    "Cannot transition to Candidate since the local id (%s) 
and directory id (%s) " +
+                    "Cannot transition to Prospective since the local id (%s) 
and directory id (%s) " +
                     "is not one of the voters %s",
                     localId,
                     localDirectoryId,
                     partitionState.lastVoterSet()
                 )
             );
-        } else if (isLeader()) {
-            throw new IllegalStateException("Cannot transition to Candidate 
since the local broker.id=" + localId +
-                " since this node is already a Leader with state " + state);
+        } else if (isLeader() || isProspective()) {
+            throw new IllegalStateException("Cannot transition to Prospective 
since the local broker.id=" + localId +
+                " is state " + state);
         }
 
         int retries = isCandidate() ? candidateStateOrThrow().retries() + 1 : 
1;
+
+        durableTransitionTo(

Review Comment:
   🤯 



-- 
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

To unsubscribe, e-mail: jira-unsubscr...@kafka.apache.org

For queries about this service, please contact Infrastructure at:
us...@infra.apache.org