timer: move Timer inteface to dbft package

Store Timer interface along with other dBFT interfaces and provide
default timer implementation in `timer` package. Create `dbft.HV`
interface and configuration for its customisation. Provide default
implementation of `dbft.HV` in `timer` package.

A part of #84.

Signed-off-by: Anna Shaleva <[email protected]>

config.go

@@ -5,7 +5,6 @@ import (
 	"errors"
 	"time"
 
-	"github.com/nspcc-dev/dbft/timer"
 	"go.uber.org/zap"
 )
 
@@ -14,7 +13,9 @@ type Config[H Hash] struct {
 	// Logger
 	Logger *zap.Logger
 	// Timer
-	Timer timer.Timer
+	Timer Timer
+	// NewHeightView is a constructor for [dbft.HV] object.
+	NewHeightView func(height uint32, view byte) HV
 	// SecondsPerBlock is the number of seconds that
 	// need to pass before another block will be accepted.
 	SecondsPerBlock time.Duration
@@ -85,7 +86,6 @@ func defaultConfig[H Hash]() *Config[H] {
 	// fields which are set to nil must be provided from client
 	return &Config[H]{
 		Logger:             zap.NewNop(),
-		Timer:              timer.New(),
 		SecondsPerBlock:    defaultSecondsPerBlock,
 		TimestampIncrement: defaultTimestampIncrement,
 		GetKeyPair:         nil,
@@ -110,6 +110,10 @@ func defaultConfig[H Hash]() *Config[H] {
 func checkConfig[H Hash](cfg *Config[H]) error {
 	if cfg.GetKeyPair == nil {
 		return errors.New("private key is nil")
+	} else if cfg.Timer == nil {
+		return errors.New("Timer is nil")
+	} else if cfg.NewHeightView == nil {
+		return errors.New("NewHeightView is nil")
 	} else if cfg.CurrentHeight == nil {
 		return errors.New("CurrentHeight is nil")
 	} else if cfg.CurrentBlockHash == nil {
@@ -176,12 +180,19 @@ func WithLogger[H Hash](log *zap.Logger) func(config *Config[H]) {
 }
 
 // WithTimer sets Timer.
-func WithTimer[H Hash](t timer.Timer) func(config *Config[H]) {
+func WithTimer[H Hash](t Timer) func(config *Config[H]) {
 	return func(cfg *Config[H]) {
 		cfg.Timer = t
 	}
 }
 
+// WithNewHeightView sets NewHeightView constructor.
+func WithNewHeightView[H Hash](f func(height uint32, view byte) HV) func(config *Config[H]) {
+	return func(cfg *Config[H]) {
+		cfg.NewHeightView = f
+	}
+}
+
 // WithSecondsPerBlock sets SecondsPerBlock.
 func WithSecondsPerBlock[H Hash](d time.Duration) func(config *Config[H]) {
 	return func(cfg *Config[H]) {

context.go

@@ -4,8 +4,6 @@ import (
 	"crypto/rand"
 	"encoding/binary"
 	"time"
-
-	"github.com/nspcc-dev/dbft/timer"
 )
 
 // Context is a main dBFT structure which
@@ -67,7 +65,7 @@ type Context[H Hash] struct {
 	LastChangeViewPayloads []ConsensusPayload[H]
 	// LastSeenMessage array stores the height of the last seen message, for each validator.
 	// if this node never heard from validator i, LastSeenMessage[i] will be -1.
-	LastSeenMessage []*timer.HV
+	LastSeenMessage []*HV
 
 	lastBlockTimestamp uint64    // ns-precision timestamp from the last header (used for the next block timestamp calculations).
 	lastBlockTime      time.Time // Wall clock time of when the last block was first seen (used for timer adjustments).
@@ -120,7 +118,7 @@ func (c *Context[H]) CountCommitted() (count int) {
 // for this view and that hasn't sent the Commit message at the previous views.
 func (c *Context[H]) CountFailed() (count int) {
 	for i, hv := range c.LastSeenMessage {
-		if c.CommitPayloads[i] == nil && (hv == nil || hv.Height < c.BlockIndex || hv.View < c.ViewNumber) {
+		if c.CommitPayloads[i] == nil && (hv == nil || (*hv).Height() < c.BlockIndex || (*hv).View() < c.ViewNumber) {
 			count++
 		}
 	}
@@ -200,7 +198,7 @@ func (c *Context[H]) reset(view byte, ts uint64) {
 		c.LastChangeViewPayloads = make([]ConsensusPayload[H], n)
 
 		if c.LastSeenMessage == nil {
-			c.LastSeenMessage = make([]*timer.HV, n)
+			c.LastSeenMessage = make([]*HV, n)
 		}
 		c.blockProcessed = false
 	} else {
@@ -233,10 +231,8 @@ func (c *Context[H]) reset(view byte, ts uint64) {
 	c.ViewNumber = view
 
 	if c.MyIndex >= 0 {
-		c.LastSeenMessage[c.MyIndex] = &timer.HV{
-			Height: c.BlockIndex,
-			View:   c.ViewNumber,
-		}
+		hv := c.Config.NewHeightView(c.BlockIndex, c.ViewNumber)
+		c.LastSeenMessage[c.MyIndex] = &hv
 	}
 }
 

dbft.go

@@ -4,7 +4,6 @@ import (
 	"sync"
 	"time"
 
-	"github.com/nspcc-dev/dbft/timer"
 	"go.uber.org/zap"
 )
 
@@ -169,22 +168,22 @@ func (d *DBFT[H]) OnTransaction(tx Transaction[H]) {
 }
 
 // OnTimeout advances state machine as if timeout was fired.
-func (d *DBFT[H]) OnTimeout(hv timer.HV) {
+func (d *DBFT[H]) OnTimeout(hv HV) {
 	if d.Context.WatchOnly() || d.BlockSent() {
 		return
 	}
 
-	if hv.Height != d.BlockIndex || hv.View != d.ViewNumber {
+	if hv.Height() != d.BlockIndex || hv.View() != d.ViewNumber {
 		d.Logger.Debug("timeout: ignore old timer",
-			zap.Uint32("height", hv.Height),
-			zap.Uint("view", uint(hv.View)))
+			zap.Uint32("height", hv.Height()),
+			zap.Uint("view", uint(hv.View())))
 
 		return
 	}
 
 	d.Logger.Debug("timeout",
-		zap.Uint32("height", hv.Height),
-		zap.Uint("view", uint(hv.View)))
+		zap.Uint32("height", hv.Height()),
+		zap.Uint("view", uint(hv.View())))
 
 	if d.IsPrimary() && !d.RequestSentOrReceived() {
 		d.sendPrepareRequest()
@@ -237,11 +236,9 @@ func (d *DBFT[H]) OnReceive(msg ConsensusPayload[H]) {
 	}
 
 	hv := d.LastSeenMessage[msg.ValidatorIndex()]
-	if hv == nil || hv.Height < msg.Height() || hv.View < msg.ViewNumber() {
-		d.LastSeenMessage[msg.ValidatorIndex()] = &timer.HV{
-			Height: msg.Height(),
-			View:   msg.ViewNumber(),
-		}
+	if hv == nil || (*hv).Height() < msg.Height() || (*hv).View() < msg.ViewNumber() {
+		hv := d.Config.NewHeightView(msg.Height(), msg.ViewNumber())
+		d.LastSeenMessage[msg.ValidatorIndex()] = &hv
 	}
 
 	if d.BlockSent() && msg.Type() != RecoveryRequestType {
@@ -612,7 +609,7 @@ func (d *DBFT[H]) changeTimer(delay time.Duration) {
 		zap.Uint32("h", d.BlockIndex),
 		zap.Int("v", int(d.ViewNumber)),
 		zap.Duration("delay", delay))
-	d.Timer.Reset(timer.HV{Height: d.BlockIndex, View: d.ViewNumber}, delay)
+	d.Timer.Reset(d.Config.NewHeightView(d.BlockIndex, d.ViewNumber), delay)
 }
 
 func (d *DBFT[H]) extendTimer(count time.Duration) {

dbft_test.go

@@ -63,7 +63,7 @@ func TestDBFT_OnStartPrimarySendPrepareRequest(t *testing.T) {
 		require.EqualValues(t, 2, p.ValidatorIndex())
 
 		t.Run("primary send ChangeView on timeout", func(t *testing.T) {
-			service.OnTimeout(timer.HV{Height: s.currHeight + 1})
+			service.OnTimeout(timer.HV{H: s.currHeight + 1})
 
 			// if there are many faulty must send RecoveryRequest
 			cv := s.tryRecv()
@@ -73,9 +73,10 @@ func TestDBFT_OnStartPrimarySendPrepareRequest(t *testing.T) {
 
 			// if all nodes are up must send ChangeView
 			for i := range service.LastSeenMessage {
-				service.LastSeenMessage[i] = &timer.HV{Height: s.currHeight + 1}
+				var hv dbft.HV = timer.HV{H: s.currHeight + 1}
+				service.LastSeenMessage[i] = &hv
 			}
-			service.OnTimeout(timer.HV{Height: s.currHeight + 1})
+			service.OnTimeout(timer.HV{H: s.currHeight + 1})
 
 			cv = s.tryRecv()
 			require.NotNil(t, cv)
@@ -166,7 +167,8 @@ func TestDBFT_OnReceiveRequestSendResponse(t *testing.T) {
 		service.Start(0)
 
 		for i := range service.LastSeenMessage {
-			service.LastSeenMessage[i] = &timer.HV{Height: s.currHeight + 1}
+			var hv dbft.HV = timer.HV{H: s.currHeight + 1}
+			service.LastSeenMessage[i] = &hv
 		}
 
 		p := s.getPrepareRequest(5, txs[0].Hash())
@@ -303,10 +305,10 @@ func TestDBFT_OnReceiveCommit(t *testing.T) {
 		require.NoError(t, service.Header().Verify(pub, cm.GetCommit().Signature()))
 
 		t.Run("send recovery message on timeout", func(t *testing.T) {
-			service.OnTimeout(timer.HV{Height: 1})
+			service.OnTimeout(timer.HV{H: 1})
 			require.Nil(t, s.tryRecv())
 
-			service.OnTimeout(timer.HV{Height: s.currHeight + 1})
+			service.OnTimeout(timer.HV{H: s.currHeight + 1})
 
 			r := s.tryRecv()
 			require.NotNil(t, r)
@@ -394,13 +396,13 @@ func TestDBFT_OnReceiveChangeView(t *testing.T) {
 		service.OnReceive(resp)
 		require.Nil(t, s.tryRecv())
 
-		service.OnTimeout(timer.HV{Height: s.currHeight + 1})
+		service.OnTimeout(timer.HV{H: s.currHeight + 1})
 		cv := s.tryRecv()
 		require.NotNil(t, cv)
 		require.Equal(t, dbft.ChangeViewType, cv.Type())
 
 		t.Run("primary sends prepare request after timeout", func(t *testing.T) {
-			service.OnTimeout(timer.HV{Height: s.currHeight + 1, View: 1})
+			service.OnTimeout(timer.HV{H: s.currHeight + 1, V: 1})
 			pr := s.tryRecv()
 			require.NotNil(t, pr)
 			require.Equal(t, dbft.PrepareRequestType, pr.Type())
@@ -418,6 +420,16 @@ func TestDBFT_Invalid(t *testing.T) {
 	require.NotNil(t, pub)
 
 	opts := []func(*dbft.Config[crypto.Uint256]){dbft.WithKeyPair[crypto.Uint256](priv, pub)}
+	t.Run("without Timer", func(t *testing.T) {
+		require.Nil(t, dbft.New(opts...))
+	})
+
+	opts = append(opts, dbft.WithTimer[crypto.Uint256](timer.New()))
+	t.Run("without NewHeightView", func(t *testing.T) {
+		require.Nil(t, dbft.New(opts...))
+	})
+
+	opts = append(opts, dbft.WithNewHeightView[crypto.Uint256](timer.NewHV))
 	t.Run("without CurrentHeight", func(t *testing.T) {
 		require.Nil(t, dbft.New(opts...))
 	})
@@ -570,7 +582,7 @@ func TestDBFT_FourGoodNodesDeadlock(t *testing.T) {
 	// (possible on timeout) and sends the ChangeView message.
 	s3.OnReceive(resp0V0)
 	s3.OnReceive(resp2V0)
-	s3.OnTimeout(timer.HV{Height: r3.currHeight + 1, View: 0})
+	s3.OnTimeout(timer.HV{H: r3.currHeight + 1, V: 0})
 	cv3V0 := r3.tryRecv()
 	require.NotNil(t, cv3V0)
 	require.Equal(t, dbft.ChangeViewType, cv3V0.Type())
@@ -580,7 +592,7 @@ func TestDBFT_FourGoodNodesDeadlock(t *testing.T) {
 	// current view) and sends the ChangeView message.
 	s1.OnReceive(resp0V0)
 	s1.OnReceive(cv3V0)
-	s1.OnTimeout(timer.HV{Height: r1.currHeight + 1, View: 0})
+	s1.OnTimeout(timer.HV{H: r1.currHeight + 1, V: 0})
 	cv1V0 := r1.tryRecv()
 	require.NotNil(t, cv1V0)
 	require.Equal(t, dbft.ChangeViewType, cv1V0.Type())
@@ -589,7 +601,7 @@ func TestDBFT_FourGoodNodesDeadlock(t *testing.T) {
 	// (possible on timeout after receiving at least M non-commit messages from the
 	// current view) and sends the ChangeView message.
 	s0.OnReceive(cv3V0)
-	s0.OnTimeout(timer.HV{Height: r0.currHeight + 1, View: 0})
+	s0.OnTimeout(timer.HV{H: r0.currHeight + 1, V: 0})
 	cv0V0 := r0.tryRecv()
 	require.NotNil(t, cv0V0)
 	require.Equal(t, dbft.ChangeViewType, cv0V0.Type())
@@ -605,7 +617,7 @@ func TestDBFT_FourGoodNodesDeadlock(t *testing.T) {
 	require.Equal(t, uint8(1), s0.ViewNumber)
 
 	// Step 10. The primary (at view 1) replica 0 sends the PrepareRequest message.
-	s0.OnTimeout(timer.HV{Height: r0.currHeight + 1, View: 1})
+	s0.OnTimeout(timer.HV{H: r0.currHeight + 1, V: 1})
 	reqV1 := r0.tryRecv()
 	require.NotNil(t, reqV1)
 	require.Equal(t, dbft.PrepareRequestType, reqV1.Type())
@@ -628,7 +640,7 @@ func TestDBFT_FourGoodNodesDeadlock(t *testing.T) {
 	// Intermediate step A. It is added to make step 14 possible. The backup (at
 	// view 1) replica 3 doesn't receive anything for a long time and sends
 	// RecoveryRequest.
-	s3.OnTimeout(timer.HV{Height: r3.currHeight + 1, View: 1})
+	s3.OnTimeout(timer.HV{H: r3.currHeight + 1, V: 1})
 	rcvr3V1 := r3.tryRecv()
 	require.NotNil(t, rcvr3V1)
 	require.Equal(t, dbft.RecoveryRequestType, rcvr3V1.Type())
@@ -663,15 +675,15 @@ func TestDBFT_FourGoodNodesDeadlock(t *testing.T) {
 	// of "lost" nodes. That's why we'he added Intermediate steps A and B.
 	//
 	// After that replica 1 is allowed to send the CV message.
-	s1.OnTimeout(timer.HV{Height: r1.currHeight + 1, View: 1})
+	s1.OnTimeout(timer.HV{H: r1.currHeight + 1, V: 1})
 	cv1V1 := r1.tryRecv()
 	require.NotNil(t, cv1V1)
 	require.Equal(t, dbft.ChangeViewType, cv1V1.Type())
 
 	// Step 13. The primary (at view 1) replica 0 decides to change its view
 	// (possible on timeout) and sends the ChangeView message.
 	s0.OnReceive(resp1V1)
-	s0.OnTimeout(timer.HV{Height: r0.currHeight + 1, View: 1})
+	s0.OnTimeout(timer.HV{H: r0.currHeight + 1, V: 1})
 	cv0V1 := r0.tryRecv()
 	require.NotNil(t, cv0V1)
 	require.Equal(t, dbft.ChangeViewType, cv0V1.Type())
@@ -806,6 +818,8 @@ func (s testState) copyWithIndex(myIndex int) *testState {
 
 func (s *testState) getOptions() []func(*dbft.Config[crypto.Uint256]) {
 	opts := []func(*dbft.Config[crypto.Uint256]){
+		dbft.WithTimer[crypto.Uint256](timer.New()),
+		dbft.WithNewHeightView[crypto.Uint256](timer.NewHV),
 		dbft.WithCurrentHeight[crypto.Uint256](func() uint32 { return s.currHeight }),
 		dbft.WithCurrentBlockHash[crypto.Uint256](func() crypto.Uint256 { return s.currHash }),
 		dbft.WithGetValidators[crypto.Uint256](func(...dbft.Transaction[crypto.Uint256]) []dbft.PublicKey { return s.pubs }),

internal/consensus/consensus.go

@@ -5,6 +5,7 @@ import (
 
 	"github.com/nspcc-dev/dbft"
 	"github.com/nspcc-dev/dbft/internal/crypto"
+	"github.com/nspcc-dev/dbft/timer"
 	"go.uber.org/zap"
 )
 
@@ -18,6 +19,8 @@ func New(logger *zap.Logger, key dbft.PrivateKey, pub dbft.PublicKey,
 	getValidators func(...dbft.Transaction[crypto.Uint256]) []dbft.PublicKey,
 	verifyPayload func(consensusPayload dbft.ConsensusPayload[crypto.Uint256]) error) *dbft.DBFT[crypto.Uint256] {
 	return dbft.New[crypto.Uint256](
+		dbft.WithTimer[crypto.Uint256](timer.New()),
+		dbft.WithNewHeightView[crypto.Uint256](timer.NewHV),
 		dbft.WithLogger[crypto.Uint256](logger),
 		dbft.WithSecondsPerBlock[crypto.Uint256](time.Second*5),
 		dbft.WithKeyPair[crypto.Uint256](key, pub),

timer.go

@@ -0,0 +1,30 @@
+package dbft
+
+import (
+	"time"
+)
+
+// Timer is an interface which implements all time-related
+// functions. It can be mocked for testing.
+type Timer interface {
+	// Now returns current time.
+	Now() time.Time
+	// Reset resets timer to the specified block height and view.
+	Reset(hv HV, d time.Duration)
+	// Sleep stops execution for duration d.
+	Sleep(d time.Duration)
+	// Extend extends current timer with duration d.
+	Extend(d time.Duration)
+	// Stop stops timer.
+	Stop()
+	// HV returns current height and view set for the timer.
+	HV() HV
+	// C returns channel for timer events.
+	C() <-chan time.Time
+}
+
+// HV is an abstraction for pair of a Height and a View.
+type HV interface {
+	Height() uint32
+	View() byte
+}