consensus: log rejected hashes on CV

Close #4148.

Signed-off-by: Anna Shaleva <shaleva.ann@nspcc.ru>

Author: AnnaShaleva

pkg/consensus/change_view.go

@@ -3,13 +3,15 @@ package consensus
 import (
 	"github.com/nspcc-dev/dbft"
 	"github.com/nspcc-dev/neo-go/pkg/io"
+	"github.com/nspcc-dev/neo-go/pkg/util"
 )
 
 // changeView represents dBFT ChangeView message.
 type changeView struct {
-	newViewNumber byte
-	timestamp     uint64
-	reason        dbft.ChangeViewReason
+	newViewNumber  byte
+	timestamp      uint64
+	reason         dbft.ChangeViewReason
+	rejectedHashes []util.Uint256
 }
 
 var _ dbft.ChangeView = (*changeView)(nil)
@@ -18,12 +20,18 @@ var _ dbft.ChangeView = (*changeView)(nil)
 func (c *changeView) EncodeBinary(w *io.BinWriter) {
 	w.WriteU64LE(c.timestamp)
 	w.WriteB(byte(c.reason))
+	if c.reason == dbft.CVTxInvalid || c.reason == dbft.CVTxRejectedByPolicy {
+		w.WriteArray(c.rejectedHashes)
+	}
 }
 
 // DecodeBinary implements the io.Serializable interface.
 func (c *changeView) DecodeBinary(r *io.BinReader) {
 	c.timestamp = r.ReadU64LE()
 	c.reason = dbft.ChangeViewReason(r.ReadB())
+	if c.reason == dbft.CVTxInvalid || c.reason == dbft.CVTxRejectedByPolicy {
+		r.ReadArray(&c.rejectedHashes)
+	}
 }
 
 // NewViewNumber implements the payload.ChangeView interface.

pkg/consensus/consensus.go

@@ -4,6 +4,7 @@ import (
 	"errors"
 	"fmt"
 	"slices"
+	"strings"
 	"sync/atomic"
 	"time"
 
@@ -354,12 +355,14 @@ events:
 				zap.Uint("view", uint(v)))
 			s.dbft.OnTimeout(h, v)
 		case msg := <-s.messages:
+			log := s.log.Debug
 			fields := []zap.Field{
 				zap.Uint8("from", msg.message.ValidatorIndex),
 				zap.Stringer("type", msg.Type()),
 			}
 
-			if msg.Type() == dbft.RecoveryMessageType {
+			switch msg.Type() {
+			case dbft.RecoveryMessageType:
 				rec := msg.GetRecoveryMessage().(*recoveryMessage)
 				if rec.preparationHash == nil {
 					req := rec.GetPrepareRequest(&msg, s.dbft.Validators, uint16(s.dbft.PrimaryIndex))
@@ -375,9 +378,24 @@ events:
 					zap.Int("#changeview", len(rec.changeViewPayloads)),
 					zap.Bool("#request", rec.prepareRequest != nil),
 					zap.Bool("#hash", rec.preparationHash != nil))
+			case dbft.ChangeViewType:
+				cv := msg.GetChangeView().(*changeView)
+				if len(cv.rejectedHashes) > 0 {
+					const maxHashes = 10
+					var rejected strings.Builder
+					log = s.log.Warn
+					for _, h := range cv.rejectedHashes[:min(len(cv.rejectedHashes), maxHashes)] { // don't pollute logs with too many hashes.
+						fmt.Fprintf(&rejected, "%s ", h.StringLE())
+					}
+					if len(cv.rejectedHashes) > maxHashes {
+						rejected.WriteString("...")
+					}
+					fields = append(fields, zap.String("rejected", rejected.String()))
+				}
+			default:
 			}
 
-			s.log.Debug("received message", fields...)
+			log("received message", fields...)
 			s.dbft.OnReceive(&msg)
 		case tx := <-s.transactions:
 			s.dbft.OnTransaction(tx)