Simplify isolated leader check

[controller.git] / opendaylight / md-sal / sal-akka-raft / src / main / java / org / opendaylight / controller / cluster / raft / behaviors / Follower.java

diff --git a/opendaylight/md-sal/sal-akka-raft/src/main/java/org/opendaylight/controller/cluster/raft/behaviors/Follower.java b/opendaylight/md-sal/sal-akka-raft/src/main/java/org/opendaylight/controller/cluster/raft/behaviors/Follower.java
index 3b1e69d0ac5c3270c0bdf761b653c974efe9de7e..33ed3357d85eab27441c7eafdd6d494974d667eb 100644 (file)
--- a/opendaylight/md-sal/sal-akka-raft/src/main/java/org/opendaylight/controller/cluster/raft/behaviors/Follower.java
+++ b/opendaylight/md-sal/sal-akka-raft/src/main/java/org/opendaylight/controller/cluster/raft/behaviors/Follower.java
@@ -9,6 +9,7 @@
 package org.opendaylight.controller.cluster.raft.behaviors;
 
 import akka.actor.ActorRef;
+import akka.japi.Procedure;
 import com.google.common.annotations.VisibleForTesting;
 import java.util.ArrayList;
 import org.opendaylight.controller.cluster.raft.RaftActorContext;
@@ -37,21 +38,33 @@ import org.opendaylight.controller.cluster.raft.messages.RequestVoteReply;
  * </ul>
  */
 public class Follower extends AbstractRaftActorBehavior {
-
-    private SnapshotTracker snapshotTracker = null;
+    private static final int SYNC_THRESHOLD = 10;
 
     private final SyncStatusTracker initialSyncStatusTracker;
 
-    private static final int SYNC_THRESHOLD = 10;
+    private final Procedure<ReplicatedLogEntry> appendAndPersistCallback = new Procedure<ReplicatedLogEntry>() {
+        @Override
+        public void apply(ReplicatedLogEntry logEntry) {
+            context.getReplicatedLog().captureSnapshotIfReady(logEntry);
+        }
+    };
+
+    private SnapshotTracker snapshotTracker = null;
 
     public Follower(RaftActorContext context) {
+        this(context, null, (short)-1);
+    }
+
+    public Follower(RaftActorContext context, String initialLeaderId, short initialLeaderPayloadVersion) {
         super(context, RaftState.Follower);
+        leaderId = initialLeaderId;
+        setLeaderPayloadVersion(initialLeaderPayloadVersion);
 
         initialSyncStatusTracker = new SyncStatusTracker(context.getActor(), getId(), SYNC_THRESHOLD);
 
-        if(context.getRaftPolicy().automaticElectionsEnabled()) {
-            if (context.getPeerIds().isEmpty()) {
-                actor().tell(ELECTION_TIMEOUT, actor());
+        if(canStartElection()) {
+            if (context.getPeerIds().isEmpty() && getLeaderId() == null) {
+                actor().tell(ElectionTimeout.INSTANCE, actor());
             } else {
                 scheduleElection(electionDuration());
             }
@@ -189,7 +202,7 @@ public class Follower extends AbstractRaftActorBehavior {
 
                 LOG.debug("{}: Append entry to log {}", logName(), entry.getData());
 
-                context.getReplicatedLog().appendAndPersist(entry);
+                context.getReplicatedLog().appendAndPersist(entry, appendAndPersistCallback);
 
                 if(entry.getData() instanceof ServerConfigurationPayload) {
                     context.updatePeerIds((ServerConfigurationPayload)entry.getData());
@@ -278,7 +291,8 @@ public class Follower extends AbstractRaftActorBehavior {
                     logName(), prevLogTerm, appendEntries.getPrevLogTerm());
         } else if(appendEntries.getPrevLogIndex() == -1 && appendEntries.getPrevLogTerm() == -1
                 && appendEntries.getReplicatedToAllIndex() != -1
-                && !isLogEntryPresent(appendEntries.getReplicatedToAllIndex())) {
+                && !isLogEntryPresent(appendEntries.getReplicatedToAllIndex())
+                && !context.getReplicatedLog().isInSnapshot(appendEntries.getReplicatedToAllIndex())) {
             // This append entry comes from a leader who has it's log aggressively trimmed and so does not have
             // the previous entry in it's in-memory journal
 
@@ -286,8 +300,9 @@ public class Follower extends AbstractRaftActorBehavior {
                     "{}: Cannot append entries because the replicatedToAllIndex {} does not appear to be in the in-memory journal",
                     logName(), appendEntries.getReplicatedToAllIndex());
         } else if(appendEntries.getPrevLogIndex() == -1 && appendEntries.getPrevLogTerm() == -1
-                && appendEntries.getReplicatedToAllIndex() != -1 && numLogEntries > 0 &&
-                !isLogEntryPresent(appendEntries.getEntries().get(0).getIndex() - 1)){
+                && appendEntries.getReplicatedToAllIndex() != -1 && numLogEntries > 0
+                && !isLogEntryPresent(appendEntries.getEntries().get(0).getIndex() - 1)
+                && !context.getReplicatedLog().isInSnapshot(appendEntries.getEntries().get(0).getIndex() - 1)) {
             LOG.debug(
                     "{}: Cannot append entries because the calculated previousIndex {} was not found in the in-memory journal",
                     logName(), appendEntries.getEntries().get(0).getIndex() - 1);
@@ -325,8 +340,12 @@ public class Follower extends AbstractRaftActorBehavior {
         }
 
         if (message instanceof ElectionTimeout) {
-            LOG.debug("{}: Received ElectionTimeout - switching to Candidate", logName());
-            return internalSwitchBehavior(RaftState.Candidate);
+            if(canStartElection()) {
+                LOG.debug("{}: Received ElectionTimeout - switching to Candidate", logName());
+                return internalSwitchBehavior(RaftState.Candidate);
+            } else {
+                return this;
+            }
 
         } else if (message instanceof InstallSnapshot) {
             InstallSnapshot installSnapshot = (InstallSnapshot) message;
@@ -342,9 +361,9 @@ public class Follower extends AbstractRaftActorBehavior {
 
     private void handleInstallSnapshot(final ActorRef sender, InstallSnapshot installSnapshot) {
 
-        LOG.debug("{}: InstallSnapshot received from leader {}, datasize: {} , Chunk: {}/{}",
-                    logName(), installSnapshot.getLeaderId(), installSnapshot.getData().size(),
-                    installSnapshot.getChunkIndex(), installSnapshot.getTotalChunks());
+        LOG.debug("{}: handleInstallSnapshot: {}", logName(), installSnapshot);
+
+        leaderId = installSnapshot.getLeaderId();
 
         if(snapshotTracker == null){
             snapshotTracker = new SnapshotTracker(LOG, installSnapshot.getTotalChunks());
@@ -366,7 +385,7 @@ public class Follower extends AbstractRaftActorBehavior {
                         installSnapshot.getLastIncludedTerm(),
                         context.getTermInformation().getCurrentTerm(),
                         context.getTermInformation().getVotedFor(),
-                        context.getPeerServerInfo());
+                        context.getPeerServerInfo(true));
 
                 ApplySnapshot.Callback applySnapshotCallback = new ApplySnapshot.Callback() {
                     @Override