* terms of the Eclipse Public License v1.0 which accompanies this distribution,
* and is available at http://www.eclipse.org/legal/epl-v10.html
*/
-
package org.opendaylight.controller.cluster.raft.behaviors;
+import static java.util.Objects.requireNonNull;
+
import akka.actor.ActorRef;
import akka.actor.Cancellable;
-import com.google.common.base.Preconditions;
+import akka.cluster.Cluster;
+import akka.cluster.Member;
+import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
+import java.util.Optional;
import java.util.Random;
+import java.util.Set;
import java.util.concurrent.TimeUnit;
-import org.opendaylight.controller.cluster.raft.ClientRequestTracker;
import org.opendaylight.controller.cluster.raft.RaftActorContext;
import org.opendaylight.controller.cluster.raft.RaftState;
import org.opendaylight.controller.cluster.raft.ReplicatedLogEntry;
import org.opendaylight.controller.cluster.raft.base.messages.ElectionTimeout;
import org.opendaylight.controller.cluster.raft.messages.AppendEntries;
import org.opendaylight.controller.cluster.raft.messages.AppendEntriesReply;
+import org.opendaylight.controller.cluster.raft.messages.RaftRPC;
import org.opendaylight.controller.cluster.raft.messages.RequestVote;
import org.opendaylight.controller.cluster.raft.messages.RequestVoteReply;
import org.opendaylight.controller.cluster.raft.persisted.ApplyJournalEntries;
/**
* Used for message logging.
*/
+ @SuppressFBWarnings("SLF4J_LOGGER_SHOULD_BE_PRIVATE")
protected final Logger log;
/**
private long replicatedToAllIndex = -1;
AbstractRaftActorBehavior(final RaftActorContext context, final RaftState state) {
- this.context = Preconditions.checkNotNull(context);
- this.state = Preconditions.checkNotNull(state);
+ this.context = requireNonNull(context);
+ this.state = requireNonNull(state);
this.log = context.getLogger();
logName = String.format("%s (%s)", context.getId(), state);
}
@Override
- public void setReplicatedToAllIndex(long replicatedToAllIndex) {
+ public void setReplicatedToAllIndex(final long replicatedToAllIndex) {
this.replicatedToAllIndex = replicatedToAllIndex;
}
* @param appendEntries the message
* @return a new behavior if it was changed or the current behavior
*/
- protected RaftActorBehavior appendEntries(ActorRef sender, AppendEntries appendEntries) {
+ protected RaftActorBehavior appendEntries(final ActorRef sender, final AppendEntries appendEntries) {
// 1. Reply false if term < currentTerm (§5.1)
if (appendEntries.getTerm() < currentTerm()) {
- log.debug("{}: Cannot append entries because sender term {} is less than {}", logName(),
+ log.info("{}: Cannot append entries because sender's term {} is less than {}", logName(),
appendEntries.getTerm(), currentTerm());
sender.tell(new AppendEntriesReply(context.getId(), currentTerm(), false, lastIndex(), lastTerm(),
- context.getPayloadVersion()), actor());
+ context.getPayloadVersion(), false, false, appendEntries.getLeaderRaftVersion()), actor());
return this;
}
* @param requestVote the message
* @return a new behavior if it was changed or the current behavior
*/
- protected RaftActorBehavior requestVote(ActorRef sender, RequestVote requestVote) {
+ protected RaftActorBehavior requestVote(final ActorRef sender, final RequestVote requestVote) {
- log.debug("{}: In requestVote: {}", logName(), requestVote);
+ log.debug("{}: In requestVote: {} - currentTerm: {}, votedFor: {}, lastIndex: {}, lastTerm: {}", logName(),
+ requestVote, currentTerm(), votedFor(), lastIndex(), lastTerm());
boolean grantVote = canGrantVote(requestVote);
return this;
}
- protected boolean canGrantVote(RequestVote requestVote) {
+ protected boolean canGrantVote(final RequestVote requestVote) {
boolean grantVote = false;
// Reply false if term < currentTerm (§5.1)
*
* @param interval the duration after which we should trigger a new election
*/
- protected void scheduleElection(FiniteDuration interval) {
+ protected void scheduleElection(final FiniteDuration interval) {
stopElection();
// Schedule an election. When the scheduler triggers an ElectionTimeout message is sent to itself
return context.getReplicatedLog().lastIndex();
}
- /**
- * Removes and returns the ClientRequestTracker for the specified log index.
- * @param logIndex the log index
- * @return the ClientRequestTracker or null if none available
- */
- protected ClientRequestTracker removeClientRequestTracker(long logIndex) {
- return null;
- }
-
/**
* Returns the actual index of the entry in replicated log for the given index or -1 if not found.
*
* @return the log entry index or -1 if not found
*/
- protected long getLogEntryIndex(long index) {
+ protected long getLogEntryIndex(final long index) {
if (index == context.getReplicatedLog().getSnapshotIndex()) {
return context.getReplicatedLog().getSnapshotIndex();
}
}
/**
- * Returns the actual term of the entry in replicated log for the given index or -1 if not found.
+ * Returns the actual term of the entry in the replicated log for the given index or -1 if not found.
*
* @return the log entry term or -1 if not found
*/
- protected long getLogEntryTerm(long index) {
+ protected long getLogEntryTerm(final long index) {
if (index == context.getReplicatedLog().getSnapshotIndex()) {
return context.getReplicatedLog().getSnapshotTerm();
}
return -1;
}
+ /**
+ * Returns the actual term of the entry in the replicated log for the given index or, if not present, returns the
+ * snapshot term if the given index is in the snapshot or -1 otherwise.
+ *
+ * @return the term or -1 otherwise
+ */
+ protected long getLogEntryOrSnapshotTerm(final long index) {
+ if (context.getReplicatedLog().isInSnapshot(index)) {
+ return context.getReplicatedLog().getSnapshotTerm();
+ }
+
+ return getLogEntryTerm(index);
+ }
+
/**
* Applies the log entries up to the specified index that is known to be committed to the state machine.
*
* @param index the log index
*/
protected void applyLogToStateMachine(final long index) {
- long newLastApplied = context.getLastApplied();
// Now maybe we apply to the state machine
for (long i = context.getLastApplied() + 1; i < index + 1; i++) {
// Send a local message to the local RaftActor (it's derived class to be
// specific to apply the log to it's index)
- final ApplyState msg;
- final ClientRequestTracker tracker = removeClientRequestTracker(i);
- if (tracker != null) {
- msg = new ApplyState(tracker.getClientActor(), tracker.getIdentifier(), replicatedLogEntry);
- } else {
- msg = new ApplyState(null, null, replicatedLogEntry);
- }
+ final ApplyState applyState = getApplyStateFor(replicatedLogEntry);
- actor().tell(msg, actor());
- newLastApplied = i;
+ log.debug("{}: Setting last applied to {}", logName(), i);
+
+ context.setLastApplied(i);
+ context.getApplyStateConsumer().accept(applyState);
} else {
//if one index is not present in the log, no point in looping
// around as the rest wont be present either
}
}
- log.debug("{}: Setting last applied to {}", logName(), newLastApplied);
-
- context.setLastApplied(newLastApplied);
-
// send a message to persist a ApplyLogEntries marker message into akka's persistent journal
// will be used during recovery
//in case if the above code throws an error and this message is not sent, it would be fine
actor().tell(new ApplyJournalEntries(context.getLastApplied()), actor());
}
+ /**
+ * Create an ApplyState message for a particular log entry so we can determine how to apply this entry.
+ *
+ * @param entry the log entry
+ * @return ApplyState for this entry
+ */
+ abstract ApplyState getApplyStateFor(ReplicatedLogEntry entry);
+
@Override
- public RaftActorBehavior handleMessage(ActorRef sender, Object message) {
+ public RaftActorBehavior handleMessage(final ActorRef sender, final Object message) {
if (message instanceof AppendEntries) {
return appendEntries(sender, (AppendEntries) message);
} else if (message instanceof AppendEntriesReply) {
}
@Override
- public RaftActorBehavior switchBehavior(RaftActorBehavior behavior) {
+ public RaftActorBehavior switchBehavior(final RaftActorBehavior behavior) {
return internalSwitchBehavior(behavior);
}
- protected RaftActorBehavior internalSwitchBehavior(RaftState newState) {
+ protected RaftActorBehavior internalSwitchBehavior(final RaftState newState) {
return internalSwitchBehavior(createBehavior(context, newState));
}
@SuppressWarnings("checkstyle:IllegalCatch")
- protected RaftActorBehavior internalSwitchBehavior(RaftActorBehavior newBehavior) {
+ protected RaftActorBehavior internalSwitchBehavior(final RaftActorBehavior newBehavior) {
if (!context.getRaftPolicy().automaticElectionsEnabled()) {
return this;
}
- log.info("{} :- Switching from behavior {} to {}", logName(), this.state(), newBehavior.state());
+ log.info("{} :- Switching from behavior {} to {}, election term: {}", logName(), this.state(),
+ newBehavior.state(), context.getTermInformation().getCurrentTerm());
try {
close();
} catch (RuntimeException e) {
}
- protected int getMajorityVoteCount(int numPeers) {
+ protected int getMajorityVoteCount(final int numPeers) {
// Votes are required from a majority of the peers including self.
// The numMajority field therefore stores a calculated value
// of the number of votes required for this candidate to win an
protected String getId() {
return context.getId();
}
+
+ // Check whether we should update the term. In case of half-connected nodes, we want to ignore RequestVote
+ // messages, as the candidate is not able to receive our response.
+ protected boolean shouldUpdateTerm(final RaftRPC rpc) {
+ if (!(rpc instanceof RequestVote)) {
+ return true;
+ }
+
+ final RequestVote requestVote = (RequestVote) rpc;
+ log.debug("{}: Found higher term in RequestVote rpc, verifying whether it's safe to update term.", logName());
+ final Optional<Cluster> maybeCluster = context.getCluster();
+ if (!maybeCluster.isPresent()) {
+ return true;
+ }
+
+ final Cluster cluster = maybeCluster.get();
+
+ final Set<Member> unreachable = cluster.state().getUnreachable();
+ log.debug("{}: Cluster state: {}", logName(), unreachable);
+
+ for (Member member : unreachable) {
+ for (String role : member.getRoles()) {
+ if (requestVote.getCandidateId().startsWith(role)) {
+ log.debug("{}: Unreachable member: {}, matches candidateId in: {}, not updating term", logName(),
+ member, requestVote);
+ return false;
+ }
+ }
+ }
+
+ log.debug("{}: Candidate in requestVote:{} with higher term appears reachable, updating term.", logName(),
+ requestVote);
+ return true;
+ }
}