[viewchange] only rotate leader among harmony nodes

Signed-off-by: Leo Chen <leo@harmony.one>

consensus/quorum/quorum.go

@@ -10,6 +10,7 @@ import (
 	bls_core "github.com/harmony-one/bls/ffi/go/bls"
 	"github.com/harmony-one/harmony/consensus/votepower"
 	bls_cosi "github.com/harmony-one/harmony/crypto/bls"
+	shardingconfig "github.com/harmony-one/harmony/internal/configs/sharding"
 	"github.com/harmony-one/harmony/multibls"
 	"github.com/harmony-one/harmony/numeric"
 	"github.com/harmony-one/harmony/shard"
@@ -73,6 +74,7 @@ type ParticipantTracker interface {
 	IndexOf(bls.SerializedPublicKey) int
 	ParticipantsCount() int64
 	NthNext(*bls.PublicKeyWrapper, int) (bool, *bls.PublicKeyWrapper)
+	NthNextHmy(shardingconfig.Instance, *bls.PublicKeyWrapper, int) (bool, *bls.PublicKeyWrapper)
 	UpdateParticipants(pubKeys []bls.PublicKeyWrapper)
 }
 
@@ -214,7 +216,29 @@ func (s *cIdentities) NthNext(pubKey *bls.PublicKeyWrapper, next int) (bool, *bl
 	if idx != -1 {
 		found = true
 	}
-	idx = (idx + next) % int(s.ParticipantsCount())
+	numNodes := int(s.ParticipantsCount())
+	// sanity check to avoid out of bound access
+	if numNodes <= 0 || numNodes > len(s.publicKeys) {
+		numNodes = len(s.publicKeys)
+	}
+	idx = (idx + next) % numNodes
+	return found, &s.publicKeys[idx]
+}
+
+// NthNextHmy return the Nth next pubkey of Harmony nodes, next can be negative number
+func (s *cIdentities) NthNextHmy(instance shardingconfig.Instance, pubKey *bls.PublicKeyWrapper, next int) (bool, *bls.PublicKeyWrapper) {
+	found := false
+
+	idx := s.IndexOf(pubKey.Bytes)
+	if idx != -1 {
+		found = true
+	}
+	numNodes := instance.NumHarmonyOperatedNodesPerShard()
+	// sanity check to avoid out of bound access
+	if numNodes <= 0 || numNodes > len(s.publicKeys) {
+		numNodes = len(s.publicKeys)
+	}
+	idx = (idx + next) % numNodes
 	return found, &s.publicKeys[idx]
 }
 

consensus/view_change.go

@@ -1,6 +1,7 @@
 package consensus
 
 import (
+	"math/big"
 	"sync"
 	"time"
 
@@ -13,6 +14,7 @@ import (
 	nodeconfig "github.com/harmony-one/harmony/internal/configs/node"
 	"github.com/harmony-one/harmony/internal/utils"
 	"github.com/harmony-one/harmony/p2p"
+	"github.com/harmony-one/harmony/shard"
 	"github.com/pkg/errors"
 )
 
@@ -159,6 +161,7 @@ func (consensus *Consensus) getNextLeaderKey(viewID uint64) *bls.PublicKeyWrappe
 	}
 	var lastLeaderPubKey *bls.PublicKeyWrapper
 	var err error
+	epoch := big.NewInt(0)
 	if consensus.ChainReader == nil {
 		consensus.getLogger().Error().Msg("[getNextLeaderKey] ChainReader is nil. Use consensus.LeaderPubKey")
 		lastLeaderPubKey = consensus.LeaderPubKey
@@ -175,6 +178,7 @@ func (consensus *Consensus) getNextLeaderKey(viewID uint64) *bls.PublicKeyWrappe
 					Msg("[getNextLeaderKey] Unable to get leaderPubKey from coinbase. Set it to consensus.LeaderPubKey")
 				lastLeaderPubKey = consensus.LeaderPubKey
 			}
+			epoch = curHeader.Epoch()
 			// viewchange happened at the first block of new epoch
 			// use the LeaderPubKey as the base of the next leader
 			// as we shouldn't use lastLeader from coinbase as the base.
@@ -192,7 +196,12 @@ func (consensus *Consensus) getNextLeaderKey(viewID uint64) *bls.PublicKeyWrappe
 		Uint64("newViewID", viewID).
 		Uint64("myCurBlockViewID", consensus.GetCurBlockViewID()).
 		Msg("[getNextLeaderKey] got leaderPubKey from coinbase")
-	wasFound, next := consensus.Decider.NthNext(lastLeaderPubKey, gap)
+	// wasFound, next := consensus.Decider.NthNext(lastLeaderPubKey, gap)
+	// FIXME: rotate leader on harmony nodes only before fully externalization
+	wasFound, next := consensus.Decider.NthNextHmy(
+		shard.Schedule.InstanceForEpoch(epoch),
+		lastLeaderPubKey,
+		gap)
 	if !wasFound {
 		consensus.getLogger().Warn().
 			Str("key", consensus.LeaderPubKey.Bytes.Hex()).