chained rolldpos scheme

Author: envestcc

consensus/consensusfsm/chainedfsm.go

@@ -0,0 +1,182 @@
+package consensusfsm
+
+import (
+	"github.com/facebookgo/clock"
+	fsm "github.com/iotexproject/go-fsm"
+	"github.com/pkg/errors"
+)
+
+const (
+	// consensus states
+	SFinalized fsm.State = "S_FINALIZED"
+	SInvalid   fsm.State = "S_INVALID"
+)
+
+type ChainedConsensusFSM struct {
+	*ConsensusFSM
+}
+
+func NewChainedConsensusFSM(ctx Context, clock clock.Clock) (*ChainedConsensusFSM, error) {
+	mm := &ConsensusFSM{
+		evtq:  make(chan *ConsensusEvent, ctx.EventChanSize()),
+		close: make(chan interface{}),
+		ctx:   ctx,
+		clock: clock,
+	}
+	cm := &ChainedConsensusFSM{
+		ConsensusFSM: mm,
+	}
+	b := fsm.NewBuilder().
+		AddInitialState(sPrepare).
+		AddStates(
+			sAcceptBlockProposal,
+			sAcceptProposalEndorsement,
+			sAcceptLockEndorsement,
+			sAcceptPreCommitEndorsement,
+			SInvalid,
+			SFinalized,
+		).
+		AddTransition(sPrepare, ePrepare, cm.prepare, []fsm.State{
+			sPrepare,
+			sAcceptBlockProposal,
+			sAcceptPreCommitEndorsement,
+		}).
+		AddTransition(
+			sAcceptBlockProposal,
+			eReceiveBlock,
+			cm.onReceiveBlock,
+			[]fsm.State{
+				sAcceptBlockProposal,       // proposed block invalid
+				sAcceptProposalEndorsement, // receive valid block, jump to next step
+			}).
+		AddTransition(
+			sAcceptBlockProposal,
+			eFailedToReceiveBlock,
+			cm.onFailedToReceiveBlock,
+			[]fsm.State{
+				sAcceptProposalEndorsement, // no valid block, jump to next step
+			}).
+		AddTransition(
+			sAcceptProposalEndorsement,
+			eReceiveProposalEndorsement,
+			cm.onReceiveProposalEndorsementInAcceptProposalEndorsementState,
+			[]fsm.State{
+				sAcceptProposalEndorsement, // not enough endorsements
+				sAcceptLockEndorsement,     // enough endorsements
+			}).
+		AddTransition(
+			sAcceptProposalEndorsement,
+			eReceivePreCommitEndorsement,
+			cm.onReceiveProposalEndorsementInAcceptProposalEndorsementState,
+			[]fsm.State{
+				sAcceptProposalEndorsement, // not enough endorsements
+				sAcceptLockEndorsement,     // enough endorsements
+			}).
+		AddTransition(
+			sAcceptProposalEndorsement,
+			eStopReceivingProposalEndorsement,
+			cm.onStopReceivingProposalEndorsement,
+			[]fsm.State{
+				sAcceptLockEndorsement, // timeout, jump to next step
+			}).
+		AddTransition(
+			sAcceptLockEndorsement,
+			eReceiveProposalEndorsement,
+			cm.onReceiveProposalEndorsementInAcceptLockEndorsementState,
+			[]fsm.State{
+				sAcceptLockEndorsement,
+			},
+		).
+		AddTransition(
+			sAcceptLockEndorsement,
+			eReceiveLockEndorsement,
+			cm.onReceiveLockEndorsement,
+			[]fsm.State{
+				sAcceptLockEndorsement,      // not enough endorsements
+				sAcceptPreCommitEndorsement, // reach commit agreement, jump to next step
+			}).
+		AddTransition(
+			sAcceptLockEndorsement,
+			eReceivePreCommitEndorsement,
+			cm.onReceiveLockEndorsement,
+			[]fsm.State{
+				sAcceptLockEndorsement,      // not enough endorsements
+				sAcceptPreCommitEndorsement, // reach commit agreement, jump to next step
+			}).
+		AddTransition(
+			sAcceptLockEndorsement,
+			eStopReceivingLockEndorsement,
+			cm.onStopReceivingLockEndorsement,
+			[]fsm.State{
+				SInvalid, // timeout, invalid
+			}).
+		AddTransition(
+			sAcceptPreCommitEndorsement,
+			eBroadcastPreCommitEndorsement,
+			cm.onBroadcastPreCommitEndorsement,
+			[]fsm.State{
+				sAcceptPreCommitEndorsement,
+			}).
+		AddTransition(
+			sAcceptPreCommitEndorsement,
+			eStopReceivingPreCommitEndorsement,
+			cm.onStopReceivingPreCommitEndorsement,
+			[]fsm.State{
+				SInvalid,
+			}).
+		AddTransition(
+			sAcceptPreCommitEndorsement,
+			eReceivePreCommitEndorsement,
+			cm.onReceivePreCommitEndorsement,
+			[]fsm.State{
+				sAcceptPreCommitEndorsement,
+				SFinalized, // reach consensus, start next epoch
+			})
+	// Add the backdoor transition so that we could unit test the transition from any given state
+	for _, state := range consensusStates {
+		b = b.AddTransition(state, BackdoorEvent, cm.handleBackdoorEvt, consensusStates)
+		if state != sPrepare {
+			b = b.AddTransition(state, eCalibrate, cm.calibrate, []fsm.State{sPrepare, state})
+		}
+	}
+	m, err := b.Build()
+	if err != nil {
+		return nil, errors.Wrap(err, "error when building the FSM")
+	}
+	cm.fsm = m
+	return cm, nil
+}
+
+func (m *ChainedConsensusFSM) onStopReceivingLockEndorsement(evt fsm.Event) (fsm.State, error) {
+	m.ctx.Logger().Warn("Not enough lock endorsements")
+
+	return m.Invalid()
+}
+
+func (m *ChainedConsensusFSM) onStopReceivingPreCommitEndorsement(evt fsm.Event) (fsm.State, error) {
+	m.ctx.Logger().Warn("Not enough pre-commit endorsements")
+
+	return m.Invalid()
+}
+
+func (m *ChainedConsensusFSM) onReceivePreCommitEndorsement(evt fsm.Event) (fsm.State, error) {
+	cEvt, ok := evt.(*ConsensusEvent)
+	if !ok {
+		return sAcceptPreCommitEndorsement, errors.Wrap(ErrEvtCast, "failed to cast to consensus event")
+	}
+	committed, err := m.ctx.Commit(cEvt.Data())
+	if err != nil || !committed {
+		return sAcceptPreCommitEndorsement, err
+	}
+	return SFinalized, nil
+}
+
+func (m *ChainedConsensusFSM) Finalize() (fsm.State, error) {
+	m.ctx.Logger().Warn("Finalized")
+	return SFinalized, nil
+}
+
+func (m *ChainedConsensusFSM) Invalid() (fsm.State, error) {
+	m.ctx.Logger().Warn("Invalid")
+	return SInvalid, nil
+}

consensus/consensusfsm/context.go

@@ -25,6 +25,7 @@ type Context interface {
 
 	Logger() *zap.Logger
 	Height() uint64
+	Number() uint32
 
 	NewConsensusEvent(fsm.EventType, interface{}) *ConsensusEvent
 	NewBackdoorEvt(fsm.State) *ConsensusEvent

consensus/consensusfsm/fsm.go

@@ -305,6 +305,7 @@ func (m *ConsensusFSM) produce(evt *ConsensusEvent, delay time.Duration) {
 	if evt == nil {
 		return
 	}
+	// m.ctx.Logger().Debug("produce event", zap.Any("event", evt.Type()), zap.Stack("stack"))
 	_consensusEvtsMtc.WithLabelValues(string(evt.Type()), "produced").Inc()
 	if delay > 0 {
 		m.wg.Add(1)
@@ -328,7 +329,7 @@ func (m *ConsensusFSM) handle(evt *ConsensusEvent) error {
 		return nil
 	}
 	if m.ctx.IsFutureEvent(evt) {
-		m.ctx.Logger().Debug("future event", zap.Any("event", evt.Type()))
+		m.ctx.Logger().Debug("future event", zap.Any("event", evt.Type()), zap.Any("eventHeight", evt.Height()), zap.Any("eventRount", evt.Round()))
 		// TODO: find a more appropriate delay
 		m.produce(evt, m.ctx.UnmatchedEventInterval(evt.Height()))
 		_consensusEvtsMtc.WithLabelValues(string(evt.Type()), "backoff").Inc()
@@ -397,10 +398,10 @@ func (m *ConsensusFSM) calibrate(evt fsm.Event) (fsm.State, error) {
 
 func (m *ConsensusFSM) prepare(evt fsm.Event) (fsm.State, error) {
 	if err := m.ctx.Prepare(); err != nil {
-		m.ctx.Logger().Error("Error during prepare", zap.Error(err))
+		m.ctx.Logger().Error("Error during prepare", zap.Error(err), zap.Stack("stack"))
 		return m.BackToPrepare(0)
 	}
-	m.ctx.Logger().Debug("Start a new round")
+	m.ctx.Logger().Debug("Start a new round", zap.Stack("stack"))
 	proposal, err := m.ctx.Proposal()
 	if err != nil {
 		m.ctx.Logger().Error("failed to generate block proposal", zap.Error(err))