package org.opendaylight.controller.cluster.raft.behaviors;
import akka.actor.ActorRef;
+import akka.japi.Procedure;
import com.google.common.annotations.VisibleForTesting;
+import com.google.common.base.Preconditions;
import java.util.ArrayList;
import org.opendaylight.controller.cluster.raft.RaftActorContext;
import org.opendaylight.controller.cluster.raft.RaftState;
* </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;
+ private String leaderId;
+ private short leaderPayloadVersion;
public Follower(RaftActorContext context) {
- this(context, null);
+ this(context, null, (short)-1);
}
- public Follower(RaftActorContext context, String initialLeaderId) {
+ public Follower(RaftActorContext context, String initialLeaderId, short initialLeaderPayloadVersion) {
super(context, RaftState.Follower);
- leaderId = initialLeaderId;
+ this.leaderId = initialLeaderId;
+ this.leaderPayloadVersion = initialLeaderPayloadVersion;
initialSyncStatusTracker = new SyncStatusTracker(context.getActor(), getId(), SYNC_THRESHOLD);
if(canStartElection()) {
if (context.getPeerIds().isEmpty() && getLeaderId() == null) {
- actor().tell(ELECTION_TIMEOUT, actor());
+ actor().tell(ElectionTimeout.INSTANCE, actor());
} else {
scheduleElection(electionDuration());
}
}
+ }
+ @Override
+ public final String getLeaderId() {
+ return leaderId;
+ }
+
+ @VisibleForTesting
+ protected final void setLeaderId(final String leaderId) {
+ this.leaderId = Preconditions.checkNotNull(leaderId);
+ }
+
+ @Override
+ public short getLeaderPayloadVersion() {
+ return leaderPayloadVersion;
+ }
+
+ @VisibleForTesting
+ protected final void setLeaderPayloadVersion(short leaderPayloadVersion) {
+ this.leaderPayloadVersion = leaderPayloadVersion;
}
private boolean isLogEntryPresent(long index){
initialSyncStatusTracker.update(leaderId, currentLeaderCommit, context.getCommitIndex());
}
- @Override protected RaftActorBehavior handleAppendEntries(ActorRef sender,
- AppendEntries appendEntries) {
+ @Override
+ protected RaftActorBehavior handleAppendEntries(ActorRef sender, AppendEntries appendEntries) {
int numLogEntries = appendEntries.getEntries() != null ? appendEntries.getEntries().size() : 0;
if(LOG.isTraceEnabled()) {
// If we got here then we do appear to be talking to the leader
leaderId = appendEntries.getLeaderId();
-
- setLeaderPayloadVersion(appendEntries.getPayloadVersion());
+ leaderPayloadVersion = appendEntries.getPayloadVersion();
updateInitialSyncStatus(appendEntries.getLeaderCommit(), appendEntries.getLeaderId());
// First check if the logs are in sync or not
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());
// The follower's log is out of sync because the Leader's
// prevLogIndex entry was not found in it's log
- LOG.debug("{}: The log is not empty but the prevLogIndex {} was not found in it",
- logName(), appendEntries.getPrevLogIndex());
+ LOG.debug("{}: The log is not empty but the prevLogIndex {} was not found in it - lastIndex: {}, snapshotIndex: {}",
+ logName(), appendEntries.getPrevLogIndex(), lastIndex, context.getReplicatedLog().getSnapshotIndex());
} else if (lastIndex > -1 && prevEntryPresent && prevLogTerm != appendEntries.getPrevLogTerm()) {
// The follower's log is out of sync because the Leader's
return outOfSync;
}
- @Override protected RaftActorBehavior handleAppendEntriesReply(ActorRef sender,
+ @Override
+ protected RaftActorBehavior handleAppendEntriesReply(ActorRef sender,
AppendEntriesReply appendEntriesReply) {
return this;
}
- @Override protected RaftActorBehavior handleRequestVoteReply(ActorRef sender,
+ @Override
+ protected RaftActorBehavior handleRequestVoteReply(ActorRef sender,
RequestVoteReply requestVoteReply) {
return this;
}
- @Override public RaftActorBehavior handleMessage(ActorRef sender, Object originalMessage) {
-
- Object message = fromSerializableMessage(originalMessage);
-
- if (message instanceof RaftRPC) {
- RaftRPC rpc = (RaftRPC) message;
- // If RPC request or response contains term T > currentTerm:
- // set currentTerm = T, convert to follower (§5.1)
- // This applies to all RPC messages and responses
- if (rpc.getTerm() > context.getTermInformation().getCurrentTerm()) {
- LOG.debug("{}: Term {} in \"{}\" message is greater than follower's term {} - updating term",
- logName(), rpc.getTerm(), rpc, context.getTermInformation().getCurrentTerm());
-
- context.getTermInformation().updateAndPersist(rpc.getTerm(), null);
- }
- }
-
- if (message instanceof ElectionTimeout) {
- if(canStartElection()) {
+ @Override
+ public RaftActorBehavior handleMessage(ActorRef sender, Object originalMessage) {
+ if (originalMessage instanceof ElectionTimeout) {
+ if (canStartElection()) {
LOG.debug("{}: Received ElectionTimeout - switching to Candidate", logName());
return internalSwitchBehavior(RaftState.Candidate);
} else {
return this;
}
+ }
+
+ final Object message = fromSerializableMessage(originalMessage);
+ if (!(message instanceof RaftRPC)) {
+ // The rest of the processing requires the message to be a RaftRPC
+ return null;
+ }
+
+ final RaftRPC rpc = (RaftRPC) message;
+ // If RPC request or response contains term T > currentTerm:
+ // set currentTerm = T, convert to follower (§5.1)
+ // This applies to all RPC messages and responses
+ if (rpc.getTerm() > context.getTermInformation().getCurrentTerm()) {
+ LOG.debug("{}: Term {} in \"{}\" message is greater than follower's term {} - updating term",
+ logName(), rpc.getTerm(), rpc, context.getTermInformation().getCurrentTerm());
- } else if (message instanceof InstallSnapshot) {
- InstallSnapshot installSnapshot = (InstallSnapshot) message;
+ context.getTermInformation().updateAndPersist(rpc.getTerm(), null);
+ }
+
+ if (rpc instanceof InstallSnapshot) {
+ InstallSnapshot installSnapshot = (InstallSnapshot) rpc;
handleInstallSnapshot(sender, installSnapshot);
+ scheduleElection(electionDuration());
+ return this;
}
- if(message instanceof RaftRPC && (!(message instanceof RequestVote) || (canGrantVote((RequestVote) message)))){
+ if (!(rpc instanceof RequestVote) || canGrantVote((RequestVote) rpc)) {
scheduleElection(electionDuration());
}
- return super.handleMessage(sender, message);
+ return super.handleMessage(sender, rpc);
}
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();
}
@Override
- public void close() throws Exception {
+ public void close() {
stopElection();
}