chore: adding syncing tracing (#2981)

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## Overview

Follow up which adds tracing to the block syncer

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Author: chatton

block/components.go

@@ -151,6 +151,10 @@ func NewSyncComponents(
 		errorCh,
 	)
 
+	if config.Instrumentation.IsTracingEnabled() {
+		syncer.SetBlockSyncer(syncing.WithTracingBlockSyncer(syncer))
+	}
+
 	// Create submitter for sync nodes (no signer, only DA inclusion processing)
 	daSubmitter := submitting.NewDASubmitter(daClient, config, genesis, blockOpts, metrics, logger)
 	submitter := submitting.NewSubmitter(

block/internal/syncing/block_syncer.go

@@ -0,0 +1,25 @@
+package syncing
+
+import (
+	"context"
+
+	"github.com/evstack/ev-node/block/internal/common"
+	"github.com/evstack/ev-node/types"
+)
+
+// BlockSyncer defines operations for block synchronization that can be traced.
+// The Syncer implements this interface, and a tracing decorator can wrap it
+// to add OpenTelemetry spans to each operation.
+type BlockSyncer interface {
+	// TrySyncNextBlock attempts to sync the next available block from DA or P2P.
+	TrySyncNextBlock(ctx context.Context, event *common.DAHeightEvent) error
+
+	// ApplyBlock executes block transactions and returns the new state.
+	ApplyBlock(ctx context.Context, header types.Header, data *types.Data, currentState types.State) (types.State, error)
+
+	// ValidateBlock validates block structure and state transitions.
+	ValidateBlock(ctx context.Context, currState types.State, data *types.Data, header *types.SignedHeader) error
+
+	// VerifyForcedInclusionTxs verifies that forced inclusion transactions are properly handled.
+	VerifyForcedInclusionTxs(ctx context.Context, currentState types.State, data *types.Data) error
+}

block/internal/syncing/syncer.go

@@ -28,6 +28,8 @@ import (
 	"github.com/evstack/ev-node/types"
 )
 
+var _ BlockSyncer = (*Syncer)(nil)
+
 // forcedInclusionGracePeriodConfig contains internal configuration for forced inclusion grace periods.
 type forcedInclusionGracePeriodConfig struct {
 	// basePeriod is the base number of additional epochs allowed for including forced inclusion transactions
@@ -118,6 +120,10 @@ type Syncer struct {
 
 	// P2P wait coordination
 	p2pWaitState atomic.Value // stores p2pWaitState
+
+	// blockSyncer is the interface used for block sync operations.
+	// defaults to self, but can be wrapped with tracing.
+	blockSyncer BlockSyncer
 }
 
 // pendingForcedInclusionTx represents a forced inclusion transaction that hasn't been included yet
@@ -155,7 +161,7 @@ func NewSyncer(
 	blockFullnessEMA := &atomic.Pointer[float64]{}
 	blockFullnessEMA.Store(&initialFullness)
 
-	return &Syncer{
+	s := &Syncer{
 		store:                 store,
 		exec:                  exec,
 		cache:                 cache,
@@ -175,6 +181,14 @@ func NewSyncer(
 		blockFullnessEMA:      blockFullnessEMA,
 		gracePeriodConfig:     newForcedInclusionGracePeriodConfig(),
 	}
+	s.blockSyncer = s
+	return s
+}
+
+// SetBlockSyncer sets the block syncer interface, allowing injection of
+// a tracing wrapper or other decorator.
+func (s *Syncer) SetBlockSyncer(bs BlockSyncer) {
+	s.blockSyncer = bs
 }
 
 // Start begins the syncing component
@@ -515,7 +529,7 @@ func (s *Syncer) processHeightEvent(event *common.DAHeightEvent) {
 	s.cancelP2PWait(height)
 
 	// Try to sync the next block
-	if err := s.trySyncNextBlock(event); err != nil {
+	if err := s.blockSyncer.TrySyncNextBlock(s.ctx, event); err != nil {
 		s.logger.Error().Err(err).Msg("failed to sync next block")
 		// If the error is not due to an validation error, re-store the event as pending
 		switch {
@@ -559,12 +573,12 @@ var (
 	errInvalidState = errors.New("invalid state")
 )
 
-// trySyncNextBlock attempts to sync the next available block
+// TrySyncNextBlock attempts to sync the next available block
 // the event is always the next block in sequence as processHeightEvent ensures it.
-func (s *Syncer) trySyncNextBlock(event *common.DAHeightEvent) error {
+func (s *Syncer) TrySyncNextBlock(ctx context.Context, event *common.DAHeightEvent) error {
 	select {
-	case <-s.ctx.Done():
-		return s.ctx.Err()
+	case <-ctx.Done():
+		return ctx.Err()
 	default:
 	}
 
@@ -579,7 +593,7 @@ func (s *Syncer) trySyncNextBlock(event *common.DAHeightEvent) error {
 	// Compared to the executor logic where the current block needs to be applied first,
 	// here only the previous block needs to be applied to proceed to the verification.
 	// The header validation must be done before applying the block to avoid executing gibberish
-	if err := s.validateBlock(currentState, data, header); err != nil {
+	if err := s.ValidateBlock(ctx, currentState, data, header); err != nil {
 		// remove header as da included (not per se needed, but keep cache clean)
 		s.cache.RemoveHeaderDAIncluded(headerHash)
 		if !errors.Is(err, errInvalidState) && !errors.Is(err, errInvalidBlock) {
@@ -590,7 +604,7 @@ func (s *Syncer) trySyncNextBlock(event *common.DAHeightEvent) error {
 
 	// Verify forced inclusion transactions if configured
 	if event.Source == common.SourceDA {
-		if err := s.verifyForcedInclusionTxs(currentState, data); err != nil {
+		if err := s.VerifyForcedInclusionTxs(ctx, currentState, data); err != nil {
 			s.logger.Error().Err(err).Uint64("height", nextHeight).Msg("forced inclusion verification failed")
 			if errors.Is(err, errMaliciousProposer) {
 				s.cache.RemoveHeaderDAIncluded(headerHash)
@@ -600,7 +614,7 @@ func (s *Syncer) trySyncNextBlock(event *common.DAHeightEvent) error {
 	}
 
 	// Apply block
-	newState, err := s.applyBlock(header.Header, data, currentState)
+	newState, err := s.ApplyBlock(ctx, header.Header, data, currentState)
 	if err != nil {
 		return fmt.Errorf("failed to apply block: %w", err)
 	}
@@ -650,16 +664,16 @@ func (s *Syncer) trySyncNextBlock(event *common.DAHeightEvent) error {
 	return nil
 }
 
-// applyBlock applies a block to get the new state
-func (s *Syncer) applyBlock(header types.Header, data *types.Data, currentState types.State) (types.State, error) {
+// ApplyBlock applies a block to get the new state
+func (s *Syncer) ApplyBlock(ctx context.Context, header types.Header, data *types.Data, currentState types.State) (types.State, error) {
 	// Prepare transactions
 	rawTxs := make([][]byte, len(data.Txs))
 	for i, tx := range data.Txs {
 		rawTxs[i] = []byte(tx)
 	}
 
 	// Execute transactions
-	ctx := context.WithValue(s.ctx, types.HeaderContextKey, header)
+	ctx = context.WithValue(ctx, types.HeaderContextKey, header)
 	newAppHash, err := s.executeTxsWithRetry(ctx, rawTxs, header, currentState)
 	if err != nil {
 		s.sendCriticalError(fmt.Errorf("failed to execute transactions: %w", err))
@@ -705,11 +719,11 @@ func (s *Syncer) executeTxsWithRetry(ctx context.Context, rawTxs [][]byte, heade
 	return nil, nil
 }
 
-// validateBlock validates a synced block
+// ValidateBlock validates a synced block
 // NOTE: if the header was gibberish and somehow passed all validation prior but the data was correct
 // or if the data was gibberish and somehow passed all validation prior but the header was correct
 // we are still losing both in the pending event. This should never happen.
-func (s *Syncer) validateBlock(currState types.State, data *types.Data, header *types.SignedHeader) error {
+func (s *Syncer) ValidateBlock(_ context.Context, currState types.State, data *types.Data, header *types.SignedHeader) error {
 	// Set custom verifier for aggregator node signature
 	header.SetCustomVerifierForSyncNode(s.options.SyncNodeSignatureBytesProvider)
 
@@ -804,11 +818,11 @@ func (s *Syncer) getEffectiveGracePeriod() uint64 {
 	return uint64(max(effectivePeriod, minPeriod))
 }
 
-// verifyForcedInclusionTxs verifies that forced inclusion transactions from DA are properly handled.
+// VerifyForcedInclusionTxs verifies that forced inclusion transactions from DA are properly handled.
 // Note: Due to block size constraints (MaxBytes), sequencers may defer forced inclusion transactions
 // to future blocks (smoothing). This is legitimate behavior within an epoch.
 // However, ALL forced inclusion txs from an epoch MUST be included before the next epoch begins or grace boundary (whichever comes later).
-func (s *Syncer) verifyForcedInclusionTxs(currentState types.State, data *types.Data) error {
+func (s *Syncer) VerifyForcedInclusionTxs(_ context.Context, currentState types.State, data *types.Data) error {
 	if s.fiRetriever == nil {
 		return nil
 	}

block/internal/syncing/syncer_forced_inclusion_test.go

@@ -410,7 +410,7 @@ func TestVerifyForcedInclusionTxs_AllTransactionsIncluded(t *testing.T) {
 	currentState.DAHeight = 0
 
 	// Verify - should pass since all forced txs are included
-	err = s.verifyForcedInclusionTxs(currentState, data)
+	err = s.VerifyForcedInclusionTxs(context.Background(), currentState, data)
 	require.NoError(t, err)
 }
 
@@ -486,7 +486,7 @@ func TestVerifyForcedInclusionTxs_MissingTransactions(t *testing.T) {
 	currentState.DAHeight = 0
 
 	// Verify - should pass since forced tx blob may be legitimately deferred within the epoch
-	err = s.verifyForcedInclusionTxs(currentState, data)
+	err = s.VerifyForcedInclusionTxs(context.Background(), currentState, data)
 	require.NoError(t, err)
 
 	// Mock DA for next epoch to return no forced inclusion transactions
@@ -499,7 +499,7 @@ func TestVerifyForcedInclusionTxs_MissingTransactions(t *testing.T) {
 	data2 := makeData(gen.ChainID, 2, 1)
 	data2.Txs[0] = []byte("regular_tx_3")
 
-	err = s.verifyForcedInclusionTxs(currentState, data2)
+	err = s.VerifyForcedInclusionTxs(context.Background(), currentState, data2)
 	require.NoError(t, err) // Should pass since DAHeight=1 equals grace boundary, not past it
 
 	// Mock DA for height 2 to return no forced inclusion transactions
@@ -512,7 +512,7 @@ func TestVerifyForcedInclusionTxs_MissingTransactions(t *testing.T) {
 	data3 := makeData(gen.ChainID, 3, 1)
 	data3.Txs[0] = types.Tx([]byte("regular_tx_4"))
 
-	err = s.verifyForcedInclusionTxs(currentState, data3)
+	err = s.VerifyForcedInclusionTxs(context.Background(), currentState, data3)
 	require.Error(t, err)
 	require.Contains(t, err.Error(), "sequencer is malicious")
 	require.Contains(t, err.Error(), "past grace boundary")
@@ -591,7 +591,7 @@ func TestVerifyForcedInclusionTxs_PartiallyIncluded(t *testing.T) {
 	currentState.DAHeight = 0
 
 	// Verify - should pass since dataBin2 may be legitimately deferred within the epoch
-	err = s.verifyForcedInclusionTxs(currentState, data)
+	err = s.VerifyForcedInclusionTxs(context.Background(), currentState, data)
 	require.NoError(t, err)
 
 	// Mock DA for next epoch to return no forced inclusion transactions
@@ -605,7 +605,7 @@ func TestVerifyForcedInclusionTxs_PartiallyIncluded(t *testing.T) {
 	data2.Txs[0] = types.Tx([]byte("regular_tx_3"))
 
 	// Verify - should pass since we're at the grace boundary, not past it
-	err = s.verifyForcedInclusionTxs(currentState, data2)
+	err = s.VerifyForcedInclusionTxs(context.Background(), currentState, data2)
 	require.NoError(t, err)
 
 	// Mock DA for height 2 (when we move to DAHeight 2)
@@ -620,7 +620,7 @@ func TestVerifyForcedInclusionTxs_PartiallyIncluded(t *testing.T) {
 	data3 := makeData(gen.ChainID, 3, 1)
 	data3.Txs[0] = types.Tx([]byte("regular_tx_4"))
 
-	err = s.verifyForcedInclusionTxs(currentState, data3)
+	err = s.VerifyForcedInclusionTxs(context.Background(), currentState, data3)
 	require.Error(t, err)
 	require.Contains(t, err.Error(), "sequencer is malicious")
 	require.Contains(t, err.Error(), "past grace boundary")
@@ -691,7 +691,7 @@ func TestVerifyForcedInclusionTxs_NoForcedTransactions(t *testing.T) {
 	currentState.DAHeight = 0
 
 	// Verify - should pass since no forced txs to verify
-	err = s.verifyForcedInclusionTxs(currentState, data)
+	err = s.VerifyForcedInclusionTxs(context.Background(), currentState, data)
 	require.NoError(t, err)
 }
 
@@ -754,7 +754,7 @@ func TestVerifyForcedInclusionTxs_NamespaceNotConfigured(t *testing.T) {
 	currentState.DAHeight = 0
 
 	// Verify - should pass since namespace not configured
-	err = s.verifyForcedInclusionTxs(currentState, data)
+	err = s.VerifyForcedInclusionTxs(context.Background(), currentState, data)
 	require.NoError(t, err)
 }
 
@@ -841,7 +841,7 @@ func TestVerifyForcedInclusionTxs_DeferralWithinEpoch(t *testing.T) {
 	currentState.DAHeight = 104
 
 	// Verify - should pass since dataBin2 can be deferred within epoch
-	err = s.verifyForcedInclusionTxs(currentState, data1)
+	err = s.VerifyForcedInclusionTxs(context.Background(), currentState, data1)
 	require.NoError(t, err)
 
 	// Verify that dataBin2 is now tracked as pending
@@ -870,7 +870,7 @@ func TestVerifyForcedInclusionTxs_DeferralWithinEpoch(t *testing.T) {
 	data2.Txs[1] = types.Tx(dataBin2) // The deferred one we're waiting for
 
 	// Verify - should pass since dataBin2 is now included and clears pending
-	err = s.verifyForcedInclusionTxs(currentState, data2)
+	err = s.VerifyForcedInclusionTxs(context.Background(), currentState, data2)
 	require.NoError(t, err)
 
 	// Verify that pending queue is now empty (dataBin2 was included)
@@ -965,7 +965,7 @@ func TestVerifyForcedInclusionTxs_MaliciousAfterEpochEnd(t *testing.T) {
 	currentState.DAHeight = 102
 
 	// Verify - should pass, tx can be deferred within epoch
-	err = s.verifyForcedInclusionTxs(currentState, data1)
+	err = s.VerifyForcedInclusionTxs(context.Background(), currentState, data1)
 	require.NoError(t, err)
 }
 
@@ -1059,6 +1059,6 @@ func TestVerifyForcedInclusionTxs_SmoothingExceedsEpoch(t *testing.T) {
 	currentState := s.getLastState()
 	currentState.DAHeight = 102 // At epoch end
 
-	err = s.verifyForcedInclusionTxs(currentState, data1)
+	err = s.VerifyForcedInclusionTxs(context.Background(), currentState, data1)
 	require.NoError(t, err, "smoothing within epoch should be allowed")
 }

block/internal/syncing/syncer_test.go

@@ -134,19 +134,19 @@ func TestSyncer_validateBlock_DataHashMismatch(t *testing.T) {
 	data := makeData(gen.ChainID, 1, 2) // non-empty
 	_, header := makeSignedHeaderBytes(t, gen.ChainID, 1, addr, pub, signer, nil, data, nil)
 
-	err = s.validateBlock(s.getLastState(), data, header)
+	err = s.ValidateBlock(context.Background(), s.getLastState(), data, header)
 	require.NoError(t, err)
 
 	// Create header and data with mismatched hash
 	data = makeData(gen.ChainID, 1, 2) // non-empty
 	_, header = makeSignedHeaderBytes(t, gen.ChainID, 1, addr, pub, signer, nil, nil, nil)
-	err = s.validateBlock(s.getLastState(), data, header)
+	err = s.ValidateBlock(context.Background(), s.getLastState(), data, header)
 	require.Error(t, err)
 
 	// Create header and empty data
 	data = makeData(gen.ChainID, 1, 0) // empty
 	_, header = makeSignedHeaderBytes(t, gen.ChainID, 2, addr, pub, signer, nil, nil, nil)
-	err = s.validateBlock(s.getLastState(), data, header)
+	err = s.ValidateBlock(context.Background(), s.getLastState(), data, header)
 	require.Error(t, err)
 }