rework iterator state stuff

builder.go

@@ -148,9 +148,9 @@ func (sdb *builder) WriteStateDiff(
 		func(subdiv uint) {
 			g.Go(func() error {
 				a, b := subitersA[subdiv], subitersB[subdiv]
-				it, aux := utils.NewSymmetricDifferenceIterator(a, b)
+				it := utils.NewSymmetricDifferenceIterator(a, b)
 				return sdb.processAccounts(ctx,
-					it, aux,
+					it, &it.SymmDiffState,
 					params.watchedAddressesLeafPaths,
 					nodeSink, ipldSink, logger,
 				)
@@ -165,7 +165,7 @@ func (sdb *builder) WriteStateDiffTracked(
 	args Args, params Params,
 	nodeSink sdtypes.StateNodeSink,
 	ipldSink sdtypes.IPLDSink,
-	tracker tracker.Tracker,
+	tracker tracker.IteratorTracker,
 ) error {
 	defer metrics.UpdateDuration(time.Now(), metrics.IndexerMetrics.WriteStateDiffTimer)
 	// Load tries for old and new states
@@ -178,18 +178,14 @@ func (sdb *builder) WriteStateDiffTracked(
 		return fmt.Errorf("error opening new state trie: %w", err)
 	}
 
-	var subiters []trie.NodeIterator
-	var auxes []*utils.SymmDiffAux
+	var subiters, bases []trie.NodeIterator
 	// Constructor for difference iterator at a specific (recovered) path
 	makeIterator := func(key []byte) trie.NodeIterator {
 		a := triea.NodeIterator(key)
 		b := trieb.NodeIterator(key)
-		diffit, aux := utils.NewSymmetricDifferenceIterator(a, b)
-		// iterators are constructed in-order, so these will align
-		auxes = append(auxes, aux)
-		return diffit
+		return utils.NewSymmetricDifferenceIterator(a, b)
 	}
-	subiters, err = tracker.Restore(makeIterator)
+	subiters, bases, err = tracker.Restore(makeIterator)
 	if err != nil {
 		return fmt.Errorf("error restoring iterators: %w", err)
 	}
@@ -214,7 +210,7 @@ func (sdb *builder) WriteStateDiffTracked(
 		func(subdiv uint) {
 			g.Go(func() error {
 				return sdb.processAccounts(ctx,
-					subiters[subdiv], auxes[subdiv],
+					subiters[subdiv], &bases[subdiv].(*utils.SymmDiffIterator).SymmDiffState,
 					params.watchedAddressesLeafPaths,
 					nodeSink, ipldSink, logger,
 				)
@@ -225,9 +221,10 @@ func (sdb *builder) WriteStateDiffTracked(
 }
 
 // processAccounts processes account creations, deletions, and updates
+// the NodeIterator and SymmDiffIterator instances should refer to the same object, will only be used
 func (sdb *builder) processAccounts(
 	ctx context.Context,
-	it trie.NodeIterator, aux *utils.SymmDiffAux,
+	it trie.NodeIterator, symdiff *utils.SymmDiffState,
 	watchedAddressesLeafPaths [][]byte,
 	nodeSink sdtypes.StateNodeSink, ipldSink sdtypes.IPLDSink,
 	logger log.Logger,
@@ -250,7 +247,7 @@ func (sdb *builder) processAccounts(
 		if !isWatchedPathPrefix(watchedAddressesLeafPaths, it.Path()) {
 			continue
 		}
-		if aux.FromA() { // Node exists in the old trie
+		if symdiff.FromA() { // Node exists in the old trie
 			if it.Leaf() {
 				var account types.StateAccount
 				if err := rlp.DecodeBytes(it.LeafBlob(), &account); err != nil {
@@ -259,7 +256,7 @@ func (sdb *builder) processAccounts(
 				leafKey := make([]byte, len(it.LeafKey()))
 				copy(leafKey, it.LeafKey())
 
-				if aux.CommonPath() {
+				if symdiff.CommonPath() {
 					// If B also contains this leaf node, this is the old state of an updated account.
 					if update, ok := updates[string(leafKey)]; ok {
 						update.oldRoot = account.Root
@@ -284,7 +281,7 @@ func (sdb *builder) processAccounts(
 				return err
 			}
 
-			if aux.CommonPath() {
+			if symdiff.CommonPath() {
 				// If A also contains this leaf node, this is the new state of an updated account.
 				if update, ok := updates[string(accountW.LeafKey)]; ok {
 					update.new = *accountW
@@ -354,7 +351,7 @@ func (sdb *builder) processAccounts(
 		}
 	}
 
-	metrics.IndexerMetrics.DifferenceIteratorCounter.Inc(int64(aux.Count()))
+	metrics.IndexerMetrics.DifferenceIteratorCounter.Inc(int64(symdiff.Count()))
 	return it.Error()
 }
 
@@ -482,10 +479,10 @@ func (sdb *builder) processStorageUpdates(
 
 	var prevBlob []byte
 	a, b := oldTrie.NodeIterator(nil), newTrie.NodeIterator(nil)
-	it, aux := utils.NewSymmetricDifferenceIterator(a, b)
+	it := utils.NewSymmetricDifferenceIterator(a, b)
 	for it.Next(true) {
-		if aux.FromA() {
-			if it.Leaf() && !aux.CommonPath() {
+		if it.FromA() {
+			if it.Leaf() && !it.CommonPath() {
 				// If this node's leaf key is absent from B, the storage slot was vacated.
 				// In that case, emit an empty "removed" storage node record.
 				if err := storageSink(sdtypes.StorageLeafNode{

go.mod

@@ -124,7 +124,7 @@ require (
 )
 
 replace (
-	github.com/cerc-io/eth-iterator-utils => git.vdb.to/cerc-io/eth-iterator-utils v0.1.2-0.20230925184550-062eb329435f
+	github.com/cerc-io/eth-iterator-utils => git.vdb.to/cerc-io/eth-iterator-utils v0.1.2-0.20230926100620-802551012643
 	github.com/cerc-io/eth-testing => git.vdb.to/cerc-io/eth-testing v0.3.1-0.20230925181540-2ea71042e7e0
 	github.com/ethereum/go-ethereum => git.vdb.to/cerc-io/plugeth v0.0.0-20230808125822-691dc334fab1
 	github.com/openrelayxyz/plugeth-utils => git.vdb.to/cerc-io/plugeth-utils v0.0.0-20230706160122-cd41de354c46

go.sum

@@ -1,6 +1,6 @@
 cloud.google.com/go v0.26.0/go.mod h1:aQUYkXzVsufM+DwF1aE+0xfcU+56JwCaLick0ClmMTw=
-git.vdb.to/cerc-io/eth-iterator-utils v0.1.2-0.20230925184550-062eb329435f h1:sIuSkD6U7uYD/FGfvWOBViIuaHd+YhLM0Hln+4BQM10=
-git.vdb.to/cerc-io/eth-iterator-utils v0.1.2-0.20230925184550-062eb329435f/go.mod h1:Xv+d7Q11qGJcggcfxoj2JEvJJBKj0C66I6PyG5/lz9o=
+git.vdb.to/cerc-io/eth-iterator-utils v0.1.2-0.20230926100620-802551012643 h1:yJFyJgGVy1RMEJqPrTYyaB7fF1wpfx0Df5Bsunb+Lyg=
+git.vdb.to/cerc-io/eth-iterator-utils v0.1.2-0.20230926100620-802551012643/go.mod h1:Xv+d7Q11qGJcggcfxoj2JEvJJBKj0C66I6PyG5/lz9o=
 git.vdb.to/cerc-io/eth-testing v0.3.1-0.20230925181540-2ea71042e7e0 h1:fWAvsSiuDqveuxwnfc8psInfLZhMqHlQnmOpOHsd8Tk=
 git.vdb.to/cerc-io/eth-testing v0.3.1-0.20230925181540-2ea71042e7e0/go.mod h1:qdvpc/W1xvf2MKx3rMOqvFvYaYIHG77Z1g0lwsmw0Uk=
 git.vdb.to/cerc-io/plugeth v0.0.0-20230808125822-691dc334fab1 h1:KLjxHwp9Zp7xhECccmJS00RiL+VwTuUGLU7qeIctg8g=

utils/iterator.go

@@ -7,9 +7,9 @@ import (
 	"github.com/ethereum/go-ethereum/trie"
 )
 
-type symmDiffIterator struct {
+type SymmDiffIterator struct {
 	a, b iterState // Nodes returned are those in b - a and a - b (keys only)
-	SymmDiffAux
+	SymmDiffState
 }
 
 // pairs an iterator with a cache of its valid status
@@ -18,10 +18,10 @@ type iterState struct {
 	valid bool
 }
 
-// SymmDiffAux exposes state specific to symmetric difference iteration, which is not accessible
+// SymmDiffState exposes state specific to symmetric difference iteration, which is not accessible
 // from the NodeIterator interface. This includes the number of nodes seen, whether the current key
 // is common to both A and B, and whether the current node is sourced from A or B.
-type SymmDiffAux struct {
+type SymmDiffState struct {
 	yieldFromA  bool // Whether next node comes from a
 	count       int  // Number of nodes scanned on either trie
 	eqPathIndex int  // Count index of last pair of equal paths, to detect an updated key
@@ -30,14 +30,14 @@ type SymmDiffAux struct {
 // NewSymmetricDifferenceIterator constructs a trie.NodeIterator that iterates over the symmetric difference
 // of elements in a and b, i.e., the elements in a that are not in b, and vice versa.
 // Returns the iterator, and a pointer to an auxiliary object for accessing the state not exposed by the NodeIterator interface recording the number of nodes seen.
-func NewSymmetricDifferenceIterator(a, b trie.NodeIterator) (trie.NodeIterator, *SymmDiffAux) {
-	it := &symmDiffIterator{
+func NewSymmetricDifferenceIterator(a, b trie.NodeIterator) *SymmDiffIterator {
+	it := &SymmDiffIterator{
 		a: iterState{a, true},
 		b: iterState{b, true},
 		// common paths are detected by a distance <=1 between count and this index, so we start at -2
-		SymmDiffAux: SymmDiffAux{eqPathIndex: -2},
+		SymmDiffState: SymmDiffState{eqPathIndex: -2},
 	}
-	return it, &it.SymmDiffAux
+	return it
 }
 
 func (st *iterState) Next(descend bool) bool {
@@ -46,65 +46,65 @@ func (st *iterState) Next(descend bool) bool {
 }
 
 // FromA returns true if the current node is sourced from A.
-func (it *SymmDiffAux) FromA() bool {
+func (it *SymmDiffState) FromA() bool {
 	return it.yieldFromA
 }
 
 // CommonPath returns true if a node with the current path exists in each sub-iterator - i.e. it
 // represents an updated node.
-func (it *SymmDiffAux) CommonPath() bool {
+func (it *SymmDiffState) CommonPath() bool {
 	return it.count-it.eqPathIndex <= 1
 }
 
 // Count returns the number of nodes seen.
-func (it *SymmDiffAux) Count() int {
+func (it *SymmDiffState) Count() int {
 	return it.count
 }
 
-func (it *symmDiffIterator) curr() *iterState {
+func (it *SymmDiffIterator) curr() *iterState {
 	if it.yieldFromA {
 		return &it.a
 	}
 	return &it.b
 }
 
-func (it *symmDiffIterator) Hash() common.Hash {
+func (it *SymmDiffIterator) Hash() common.Hash {
 	return it.curr().Hash()
 }
 
-func (it *symmDiffIterator) Parent() common.Hash {
+func (it *SymmDiffIterator) Parent() common.Hash {
 	return it.curr().Parent()
 }
 
-func (it *symmDiffIterator) Leaf() bool {
+func (it *SymmDiffIterator) Leaf() bool {
 	return it.curr().Leaf()
 }
 
-func (it *symmDiffIterator) LeafKey() []byte {
+func (it *SymmDiffIterator) LeafKey() []byte {
 	return it.curr().LeafKey()
 }
 
-func (it *symmDiffIterator) LeafBlob() []byte {
+func (it *SymmDiffIterator) LeafBlob() []byte {
 	return it.curr().LeafBlob()
 }
 
-func (it *symmDiffIterator) LeafProof() [][]byte {
+func (it *SymmDiffIterator) LeafProof() [][]byte {
 	return it.curr().LeafProof()
 }
 
-func (it *symmDiffIterator) Path() []byte {
+func (it *SymmDiffIterator) Path() []byte {
 	return it.curr().Path()
 }
 
-func (it *symmDiffIterator) NodeBlob() []byte {
+func (it *SymmDiffIterator) NodeBlob() []byte {
 	return it.curr().NodeBlob()
 }
 
-func (it *symmDiffIterator) AddResolver(resolver trie.NodeResolver) {
+func (it *SymmDiffIterator) AddResolver(resolver trie.NodeResolver) {
 	panic("not implemented")
 }
 
-func (it *symmDiffIterator) Next(bool) bool {
+func (it *SymmDiffIterator) Next(bool) bool {
 	// NodeIterators start in a "pre-valid" state, so the first Next advances to a valid node.
 	if it.count == 0 {
 		if it.a.Next(true) {
@@ -122,7 +122,7 @@ func (it *symmDiffIterator) Next(bool) bool {
 	return it.a.valid || it.b.valid
 }
 
-func (it *symmDiffIterator) seek() {
+func (it *SymmDiffIterator) seek() {
 	// Invariants:
 	// - At the end of the function, the sub-iterator with the lexically lesser path
 	// points to the next element
@@ -163,7 +163,7 @@ func (it *symmDiffIterator) seek() {
 	}
 }
 
-func (it *symmDiffIterator) Error() error {
+func (it *SymmDiffIterator) Error() error {
 	if err := it.a.Error(); err != nil {
 		return err
 	}