//JAVA TO C# CONVERTER WARNING: Method 'throws' clauses are not available in C#:
//ORIGINAL LINE: public org.neo4j.causalclustering.core.consensus.outcome.Outcome handle(org.neo4j.causalclustering.core.consensus.RaftMessages_AppendEntries_Response response) throws java.io.IOException
public override Outcome Handle(Org.Neo4j.causalclustering.core.consensus.RaftMessages_AppendEntries_Response response)
{
if (response.Term() < Ctx.term())
{
/* Ignore responses from old terms! */
return(Outcome);
}
else if (response.Term() > Ctx.term())
{
Outcome.NextTerm = response.Term();
StepDownToFollower(Outcome, Ctx);
Log.info("Moving to FOLLOWER state after receiving append response at term %d (my term is " + "%d) from %s", response.Term(), Ctx.term(), response.From());
Outcome.replaceFollowerStates(new FollowerStates <MemberId>());
return(Outcome);
}
FollowerState follower = Ctx.followerStates().get(response.From());
if (response.Success())
{
Debug.Assert(response.MatchIndex() <= Ctx.entryLog().appendIndex());
bool followerProgressed = response.MatchIndex() > follower.MatchIndex;
Outcome.replaceFollowerStates(Outcome.FollowerStates.onSuccessResponse(response.From(), max(response.MatchIndex(), follower.MatchIndex)));
Outcome.addShipCommand(new ShipCommand.Match(response.MatchIndex(), response.From()));
/*
* Matches from older terms can in complicated leadership change / log truncation scenarios
* be overwritten, even if they were replicated to a majority of instances. Thus we must only
* consider matches from this leader's term when figuring out which have been safely replicated
* and are ready for commit.
* This is explained nicely in Figure 3.7 of the thesis
*/
bool matchInCurrentTerm = Ctx.entryLog().readEntryTerm(response.MatchIndex()) == Ctx.term();
/*
* The quorum situation may have changed only if the follower actually progressed.
*/
if (followerProgressed && matchInCurrentTerm)
{
// TODO: Test that mismatch between voting and participating members affects commit outcome
long quorumAppendIndex = Followers.quorumAppendIndex(Ctx.votingMembers(), Outcome.FollowerStates);
if (quorumAppendIndex > Ctx.commitIndex())
{
Outcome.LeaderCommit = quorumAppendIndex;
Outcome.CommitIndex = quorumAppendIndex;
Outcome.addShipCommand(new ShipCommand.CommitUpdate());
}
}
}
else // Response indicated failure.
{
if (response.AppendIndex() > -1 && response.AppendIndex() >= Ctx.entryLog().prevIndex())
{
// Signal a mismatch to the log shipper, which will serve an earlier entry.
Outcome.addShipCommand(new ShipCommand.Mismatch(response.AppendIndex(), response.From()));
}
else
{
// There are no earlier entries, message the follower that we have compacted so that
// it can take appropriate action.
RaftMessages_LogCompactionInfo compactionInfo = new RaftMessages_LogCompactionInfo(Ctx.myself(), Ctx.term(), Ctx.entryLog().prevIndex());
Org.Neo4j.causalclustering.core.consensus.RaftMessages_Directed directedCompactionInfo = new Org.Neo4j.causalclustering.core.consensus.RaftMessages_Directed(response.From(), compactionInfo);
Outcome.addOutgoingMessage(directedCompactionInfo);
}
}
return(Outcome);
}