[NOD-1417] Implement reachability (#964)

* [NOD-1417] Implement reachability

* [NOD-1417] Rename package name

* [NOD-1417] Add UpdateReindexRoot to interface api

* [NOD-1417] Remove redundant type

* [NOD-1417] Rename reachabilityTreeManager/reachabilityTree to reachabilityManager

* [NOD-1417] Fix typo

* [NOD-1417] Remove redundant copyright message

* [NOD-1417] Fix comment

domain/consensus/factory.go

@@ -25,7 +25,7 @@ import (
 	"github.com/kaspanet/kaspad/domain/consensus/processes/ghostdagmanager"
 	"github.com/kaspanet/kaspad/domain/consensus/processes/pastmediantimemanager"
 	"github.com/kaspanet/kaspad/domain/consensus/processes/pruningmanager"
-	"github.com/kaspanet/kaspad/domain/consensus/processes/reachabilitytree"
+	"github.com/kaspanet/kaspad/domain/consensus/processes/reachabilitymanager"
 	"github.com/kaspanet/kaspad/domain/consensus/processes/transactionvalidator"
 	"github.com/kaspanet/kaspad/domain/dagconfig"
 	"github.com/kaspanet/kaspad/infrastructure/db/database"
@@ -56,12 +56,14 @@ func (f *factory) NewConsensus(dagParams *dagconfig.Params, db database.Database
 	dbManager := dbmanager.New(db)
 
 	// Processes
-	reachabilityTree := reachabilitytree.New(
+	reachabilityManager := reachabilitymanager.New(
+		dbManager,
+		ghostdagDataStore,
 		blockRelationStore,
 		reachabilityDataStore)
 	dagTopologyManager := dagtopologymanager.New(
 		dbManager,
-		reachabilityTree,
+		reachabilityManager,
 		blockRelationStore)
 	ghostdagManager := ghostdagmanager.New(
 		dbManager,
@@ -137,7 +139,7 @@ func (f *factory) NewConsensus(dagParams *dagconfig.Params, db database.Database
 		pruningManager,
 		blockValidator,
 		dagTopologyManager,
-		reachabilityTree,
+		reachabilityManager,
 		difficultyManager,
 		pastMedianTimeManager,
 		ghostdagManager,

domain/consensus/model/interface_processes_reachabilitytree.go

@@ -8,4 +8,5 @@ type ReachabilityTree interface {
 	AddBlock(blockHash *externalapi.DomainHash) error
 	IsReachabilityTreeAncestorOf(blockHashA *externalapi.DomainHash, blockHashB *externalapi.DomainHash) (bool, error)
 	IsDAGAncestorOf(blockHashA *externalapi.DomainHash, blockHashB *externalapi.DomainHash) (bool, error)
+	UpdateReindexRoot(selectedTip *externalapi.DomainHash) error
 }

domain/consensus/model/reachabilitydata.go

@@ -1,5 +1,7 @@
 package model
 
+import "github.com/kaspanet/kaspad/domain/consensus/model/externalapi"
+
 // ReachabilityData holds the set of data required to answer
 // reachability queries
 type ReachabilityData struct {
@@ -23,8 +25,8 @@ type ReachabilityData struct {
 // case, and so reindexing should always succeed unless more than
 // 2^64 blocks are added to the DAG/tree.
 type ReachabilityTreeNode struct {
-	Children []*ReachabilityTreeNode
-	Parent   *ReachabilityTreeNode
+	Children []*externalapi.DomainHash
+	Parent   *externalapi.DomainHash
 
 	// interval is the index interval containing all intervals of
 	// blocks in this node's subtree
@@ -39,12 +41,6 @@ type ReachabilityInterval struct {
 	End   uint64
 }
 
-// OrderedTreeNodeSet is an ordered set of reachabilityTreeNodes
-// Note that this type does not validate order validity. It's the
-// responsibility of the caller to construct instances of this
-// type properly.
-type OrderedTreeNodeSet []*ReachabilityTreeNode
-
 // FutureCoveringTreeNodeSet represents a collection of blocks in the future of
 // a certain block. Once a block B is added to the DAG, every block A_i in
 // B's selected parent anticone must register B in its FutureCoveringTreeNodeSet. This allows
@@ -58,4 +54,4 @@ type OrderedTreeNodeSet []*ReachabilityTreeNode
 //
 // See insertNode, hasAncestorOf, and reachabilityTree.isInPast for further
 // details.
-type FutureCoveringTreeNodeSet OrderedTreeNodeSet
+type FutureCoveringTreeNodeSet []*externalapi.DomainHash

domain/consensus/processes/reachabilitymanager/fetch.go

@@ -0,0 +1,59 @@
+package reachabilitymanager
+
+import (
+	"github.com/kaspanet/kaspad/domain/consensus/model"
+	"github.com/kaspanet/kaspad/domain/consensus/model/externalapi"
+)
+
+func (rt *reachabilityManager) data(blockHash *externalapi.DomainHash) (*model.ReachabilityData, error) {
+	return rt.reachabilityDataStore.ReachabilityData(rt.databaseContext, blockHash)
+}
+
+func (rt *reachabilityManager) futureCoveringSet(blockHash *externalapi.DomainHash) ([]*externalapi.DomainHash, error) {
+	data, err := rt.data(blockHash)
+	if err != nil {
+		return nil, err
+	}
+
+	return data.FutureCoveringSet, nil
+}
+
+func (rt *reachabilityManager) treeNode(blockHash *externalapi.DomainHash) (*model.ReachabilityTreeNode, error) {
+	data, err := rt.data(blockHash)
+	if err != nil {
+		return nil, err
+	}
+
+	return data.TreeNode, nil
+}
+
+func (rt *reachabilityManager) interval(blockHash *externalapi.DomainHash) (*model.ReachabilityInterval, error) {
+	treeNode, err := rt.treeNode(blockHash)
+	if err != nil {
+		return nil, err
+	}
+
+	return treeNode.Interval, nil
+}
+
+func (rt *reachabilityManager) children(blockHash *externalapi.DomainHash) ([]*externalapi.DomainHash, error) {
+	data, err := rt.data(blockHash)
+	if err != nil {
+		return nil, err
+	}
+
+	return data.TreeNode.Children, nil
+}
+
+func (rt *reachabilityManager) parent(blockHash *externalapi.DomainHash) (*externalapi.DomainHash, error) {
+	data, err := rt.data(blockHash)
+	if err != nil {
+		return nil, err
+	}
+
+	return data.TreeNode.Parent, nil
+}
+
+func (rt *reachabilityManager) reindexRoot() (*externalapi.DomainHash, error) {
+	return rt.reachabilityDataStore.ReachabilityReindexRoot(rt.databaseContext)
+}

domain/consensus/processes/reachabilitymanager/future_covering_set.go

@@ -0,0 +1,132 @@
+package reachabilitymanager
+
+import (
+	"github.com/kaspanet/kaspad/domain/consensus/model/externalapi"
+)
+
+// futureCoveringTreeNodeSet represents a collection of blocks in the future of
+// a certain block. Once a block B is added to the DAG, every block A_i in
+// B's selected parent anticone must register B in its futureCoveringTreeNodeSet. This allows
+// to relatively quickly (O(log(|futureCoveringTreeNodeSet|))) query whether B
+// is a descendent (is in the "future") of any block that previously
+// registered it.
+//
+// Note that futureCoveringTreeNodeSet is meant to be queried only if B is not
+// a reachability tree descendant of the block in question, as reachability
+// tree queries are always O(1).
+//
+// See insertNode, hasAncestorOf, and reachabilityTree.isInPast for further
+// details.
+type futureCoveringTreeNodeSet orderedTreeNodeSet
+
+// insertToFutureCoveringSet inserts the given block into this node's FutureCoveringSet
+// while keeping it ordered by interval.
+// If a block B ∈ node.FutureCoveringSet exists such that its interval
+// contains block's interval, block need not be added. If block's
+// interval contains B's interval, it replaces it.
+//
+// Notes:
+// * Intervals never intersect unless one contains the other
+//   (this follows from the tree structure and the indexing rule).
+// * Since node.FutureCoveringSet is kept ordered, a binary search can be
+//   used for insertion/queries.
+// * Although reindexing may change a block's interval, the
+//   is-superset relation will by definition
+//   be always preserved.
+func (rt *reachabilityManager) insertToFutureCoveringSet(node, futureNode *externalapi.DomainHash) error {
+	futureCoveringSet, err := rt.futureCoveringSet(node)
+	if err != nil {
+		return err
+	}
+
+	ancestorIndex, ok, err := rt.findAncestorIndexOfNode(futureCoveringSet, futureNode)
+	if err != nil {
+		return err
+	}
+
+	if !ok {
+		newSet := append([]*externalapi.DomainHash{futureNode}, futureCoveringSet...)
+		err := rt.stageFutureCoveringSet(node, newSet)
+		if err != nil {
+			return err
+		}
+
+		return nil
+	}
+
+	candidate := futureCoveringSet[ancestorIndex]
+	candidateIsAncestorOfFutureNode, err := rt.IsReachabilityTreeAncestorOf(candidate, futureNode)
+	if err != nil {
+		return err
+	}
+
+	if candidateIsAncestorOfFutureNode {
+		// candidate is an ancestor of futureNode, no need to insert
+		return nil
+	}
+
+	futureNodeIsAncestorOfCandidate, err := rt.IsReachabilityTreeAncestorOf(futureNode, candidate)
+	if err != nil {
+		return err
+	}
+
+	if futureNodeIsAncestorOfCandidate {
+		// futureNode is an ancestor of candidate, and can thus replace it
+		newSet := make([]*externalapi.DomainHash, len(futureCoveringSet))
+		copy(newSet, futureCoveringSet)
+		newSet[ancestorIndex] = futureNode
+
+		return rt.stageFutureCoveringSet(node, newSet)
+	}
+
+	// Insert futureNode in the correct index to maintain futureCoveringTreeNodeSet as
+	// a sorted-by-interval list.
+	// Note that ancestorIndex might be equal to len(futureCoveringTreeNodeSet)
+	left := futureCoveringSet[:ancestorIndex+1]
+	right := append([]*externalapi.DomainHash{futureNode}, futureCoveringSet[ancestorIndex+1:]...)
+	newSet := append(left, right...)
+	return rt.stageFutureCoveringSet(node, newSet)
+
+}
+
+// futureCoveringSetHasAncestorOf resolves whether the given node `other` is in the subtree of
+// any node in this.FutureCoveringSet.
+// See insertNode method for the complementary insertion behavior.
+//
+// Like the insert method, this method also relies on the fact that
+// this.FutureCoveringSet is kept ordered by interval to efficiently perform a
+// binary search over this.FutureCoveringSet and answer the query in
+// O(log(|futureCoveringTreeNodeSet|)).
+func (rt *reachabilityManager) futureCoveringSetHasAncestorOf(this, other *externalapi.DomainHash) (bool, error) {
+	futureCoveringSet, err := rt.futureCoveringSet(this)
+	if err != nil {
+		return false, err
+	}
+
+	ancestorIndex, ok, err := rt.findAncestorIndexOfNode(futureCoveringSet, other)
+	if err != nil {
+		return false, err
+	}
+
+	if !ok {
+		// No candidate to contain other
+		return false, nil
+	}
+
+	candidate := futureCoveringSet[ancestorIndex]
+	return rt.IsReachabilityTreeAncestorOf(candidate, other)
+}
+
+// futureCoveringSetString returns a string representation of the intervals in this futureCoveringSet.
+func (rt *reachabilityManager) futureCoveringSetString(futureCoveringSet []*externalapi.DomainHash) (string, error) {
+	intervalsString := ""
+	for _, node := range futureCoveringSet {
+		nodeInterval, err := rt.interval(node)
+		if err != nil {
+			return "", err
+		}
+
+		intervalsString += intervalString(nodeInterval)
+	}
+	return intervalsString, nil
+}

domain/consensus/processes/reachabilitymanager/interval.go

@@ -0,0 +1,123 @@
+package reachabilitymanager
+
+import (
+	"fmt"
+	"github.com/kaspanet/kaspad/domain/consensus/model"
+	"github.com/pkg/errors"
+	"math"
+)
+
+func newReachabilityInterval(start uint64, end uint64) *model.ReachabilityInterval {
+	return &model.ReachabilityInterval{Start: start, End: end}
+}
+
+// intervalSize returns the size of this interval. Note that intervals are
+// inclusive from both sides.
+func intervalSize(ri *model.ReachabilityInterval) uint64 {
+	return ri.End - ri.Start + 1
+}
+
+// intervalSplitInHalf splits this interval by a fraction of 0.5.
+// See splitFraction for further details.
+func intervalSplitInHalf(ri *model.ReachabilityInterval) (
+	left *model.ReachabilityInterval, right *model.ReachabilityInterval, err error) {
+
+	return intervalSplitFraction(ri, 0.5)
+}
+
+// intervalSplitFraction splits this interval to two parts such that their
+// union is equal to the original interval and the first (left) part
+// contains the given fraction of the original interval's size.
+// Note: if the split results in fractional parts, this method rounds
+// the first part up and the last part down.
+func intervalSplitFraction(ri *model.ReachabilityInterval, fraction float64) (
+	left *model.ReachabilityInterval, right *model.ReachabilityInterval, err error) {
+
+	if fraction < 0 || fraction > 1 {
+		return nil, nil, errors.Errorf("fraction must be between 0 and 1")
+	}
+	if intervalSize(ri) == 0 {
+		return nil, nil, errors.Errorf("cannot split an empty interval")
+	}
+
+	allocationSize := uint64(math.Ceil(float64(intervalSize(ri)) * fraction))
+	left = newReachabilityInterval(ri.Start, ri.Start+allocationSize-1)
+	right = newReachabilityInterval(ri.Start+allocationSize, ri.End)
+	return left, right, nil
+}
+
+// intervalSplitExact splits this interval to exactly |sizes| parts where
+// |part_i| = sizes[i]. This method expects sum(sizes) to be exactly
+// equal to the interval's size.
+func intervalSplitExact(ri *model.ReachabilityInterval, sizes []uint64) ([]*model.ReachabilityInterval, error) {
+	sizesSum := uint64(0)
+	for _, size := range sizes {
+		sizesSum += size
+	}
+	if sizesSum != intervalSize(ri) {
+		return nil, errors.Errorf("sum of sizes must be equal to the interval's size")
+	}
+
+	intervals := make([]*model.ReachabilityInterval, len(sizes))
+	start := ri.Start
+	for i, size := range sizes {
+		intervals[i] = newReachabilityInterval(start, start+size-1)
+		start += size
+	}
+	return intervals, nil
+}
+
+// intervalSplitWithExponentialBias splits this interval to |sizes| parts
+// by the allocation rule described below. This method expects sum(sizes)
+// to be smaller or equal to the interval's size. Every part_i is
+// allocated at least sizes[i] capacity. The remaining budget is
+// split by an exponentially biased rule described below.
+//
+// This rule follows the GHOSTDAG protocol behavior where the child
+// with the largest subtree is expected to dominate the competition
+// for new blocks and thus grow the most. However, we may need to
+// add slack for non-largest subtrees in order to make CPU reindexing
+// attacks unworthy.
+func intervalSplitWithExponentialBias(ri *model.ReachabilityInterval, sizes []uint64) ([]*model.ReachabilityInterval, error) {
+	intervalSize := intervalSize(ri)
+	sizesSum := uint64(0)
+	for _, size := range sizes {
+		sizesSum += size
+	}
+	if sizesSum > intervalSize {
+		return nil, errors.Errorf("sum of sizes must be less than or equal to the interval's size")
+	}
+	if sizesSum == intervalSize {
+		return intervalSplitExact(ri, sizes)
+	}
+
+	// Add a fractional bias to every size in the given sizes
+	totalBias := intervalSize - sizesSum
+	remainingBias := totalBias
+	biasedSizes := make([]uint64, len(sizes))
+	fractions := exponentialFractions(sizes)
+	for i, fraction := range fractions {
+		var bias uint64
+		if i == len(fractions)-1 {
+			bias = remainingBias
+		} else {
+			bias = uint64(math.Round(float64(totalBias) * fraction))
+			if bias > remainingBias {
+				bias = remainingBias
+			}
+		}
+		biasedSizes[i] = sizes[i] + bias
+		remainingBias -= bias
+	}
+	return intervalSplitExact(ri, biasedSizes)
+}
+
+// intervalContains returns true if ri contains other.
+func intervalContains(ri *model.ReachabilityInterval, other *model.ReachabilityInterval) bool {
+	return ri.Start <= other.Start && other.End <= ri.End
+}
+
+// intervalString returns a string representation of the interval.
+func intervalString(ri *model.ReachabilityInterval) string {
+	return fmt.Sprintf("[%d,%d]", ri.Start, ri.End)
+}

domain/consensus/processes/reachabilitymanager/log.go

@@ -0,0 +1,7 @@
+package reachabilitymanager
+
+import (
+	"github.com/kaspanet/kaspad/infrastructure/logger"
+)
+
+var log, _ = logger.Get(logger.SubsystemTags.REAC)

domain/consensus/processes/reachabilitymanager/ordered_tree_node_set.go

@@ -0,0 +1,79 @@
+package reachabilitymanager
+
+import (
+	"github.com/kaspanet/kaspad/domain/consensus/model"
+	"github.com/kaspanet/kaspad/domain/consensus/model/externalapi"
+)
+
+// orderedTreeNodeSet is an ordered set of model.ReachabilityTreeNodes
+// Note that this type does not validate order validity. It's the
+// responsibility of the caller to construct instances of this
+// type properly.
+type orderedTreeNodeSet []*externalapi.DomainHash
+
+// findAncestorOfNode finds the reachability tree ancestor of `node`
+// among the nodes in `tns`.
+func (rt *reachabilityManager) findAncestorOfNode(tns orderedTreeNodeSet, node *externalapi.DomainHash) (*externalapi.DomainHash, bool) {
+	ancestorIndex, ok, err := rt.findAncestorIndexOfNode(tns, node)
+	if err != nil {
+		return nil, false
+	}
+
+	if !ok {
+		return nil, false
+	}
+
+	return tns[ancestorIndex], true
+}
+
+// findAncestorIndexOfNode finds the index of the reachability tree
+// ancestor of `node` among the nodes in `tns`. It does so by finding
+// the index of the block with the maximum start that is below the
+// given block.
+func (rt *reachabilityManager) findAncestorIndexOfNode(tns orderedTreeNodeSet, node *externalapi.DomainHash) (int, bool, error) {
+	treeNode, err := rt.treeNode(node)
+	if err != nil {
+		return 0, false, err
+	}
+
+	blockInterval := treeNode.Interval
+	end := blockInterval.End
+
+	low := 0
+	high := len(tns)
+	for low < high {
+		middle := (low + high) / 2
+		middleInterval, err := rt.interval(tns[middle])
+		if err != nil {
+			return 0, false, err
+		}
+
+		if end < middleInterval.Start {
+			high = middle
+		} else {
+			low = middle + 1
+		}
+	}
+
+	if low == 0 {
+		return 0, false, nil
+	}
+	return low - 1, true, nil
+}
+
+func (rt *reachabilityManager) propagateIntervals(tns orderedTreeNodeSet, intervals []*model.ReachabilityInterval,
+	subtreeSizeMaps []map[externalapi.DomainHash]uint64) error {
+
+	for i, node := range tns {
+		err := rt.stageInterval(node, intervals[i])
+		if err != nil {
+			return err
+		}
+		subtreeSizeMap := subtreeSizeMaps[i]
+		err = rt.propagateInterval(node, subtreeSizeMap)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}

domain/consensus/processes/reachabilitymanager/reachability.go

@@ -0,0 +1,30 @@
+package reachabilitymanager
+
+import (
+	"github.com/kaspanet/kaspad/domain/consensus/model/externalapi"
+)
+
+// IsDAGAncestorOf returns true if blockHashA is an ancestor of
+// blockHashB in the DAG.
+//
+// Note: this method will return true if blockHashA == blockHashB
+// The complexity of this method is O(log(|this.futureCoveringTreeNodeSet|))
+func (rt *reachabilityManager) IsDAGAncestorOf(blockHashA, blockHashB *externalapi.DomainHash) (bool, error) {
+	// Check if this node is a reachability tree ancestor of the
+	// other node
+	isReachabilityTreeAncestor, err := rt.IsReachabilityTreeAncestorOf(blockHashA, blockHashB)
+	if err != nil {
+		return false, err
+	}
+	if isReachabilityTreeAncestor {
+		return true, nil
+	}
+
+	// Otherwise, use previously registered future blocks to complete the
+	// reachability test
+	return rt.futureCoveringSetHasAncestorOf(blockHashA, blockHashB)
+}
+
+func (rt *reachabilityManager) UpdateReindexRoot(selectedTip *externalapi.DomainHash) error {
+	return rt.updateReindexRoot(selectedTip)
+}

domain/consensus/processes/reachabilitymanager/reachabilitymanager.go

@@ -0,0 +1,77 @@
+package reachabilitymanager
+
+import (
+	"github.com/kaspanet/kaspad/domain/consensus/model"
+	"github.com/kaspanet/kaspad/domain/consensus/model/externalapi"
+)
+
+// reachabilityManager maintains a structure that allows to answer
+// reachability queries in sub-linear time
+type reachabilityManager struct {
+	databaseContext       model.DBReader
+	blockRelationStore    model.BlockRelationStore
+	reachabilityDataStore model.ReachabilityDataStore
+	ghostdagDataStore     model.GHOSTDAGDataStore
+}
+
+// New instantiates a new reachabilityManager
+func New(
+	databaseContext model.DBReader,
+	ghostdagDataStore model.GHOSTDAGDataStore,
+	blockRelationStore model.BlockRelationStore,
+	reachabilityDataStore model.ReachabilityDataStore,
+) model.ReachabilityTree {
+	return &reachabilityManager{
+		databaseContext:       databaseContext,
+		ghostdagDataStore:     ghostdagDataStore,
+		blockRelationStore:    blockRelationStore,
+		reachabilityDataStore: reachabilityDataStore,
+	}
+}
+
+// AddBlock adds the block with the given blockHash into the reachability tree.
+func (rt *reachabilityManager) AddBlock(blockHash *externalapi.DomainHash) error {
+	// Allocate a new reachability tree node
+	newTreeNode := newReachabilityTreeNode()
+	err := rt.stageTreeNode(blockHash, newTreeNode)
+	if err != nil {
+		return err
+	}
+
+	ghostdagData, err := rt.ghostdagDataStore.Get(rt.databaseContext, blockHash)
+	if err != nil {
+		return err
+	}
+
+	// If this is the genesis node, simply initialize it and return
+	if ghostdagData.SelectedParent == nil {
+		rt.stageReindexRoot(blockHash)
+		return nil
+	}
+
+	reindexRoot, err := rt.reindexRoot()
+	if err != nil {
+		return err
+	}
+
+	// Insert the node into the selected parent's reachability tree
+	err = rt.addChild(ghostdagData.SelectedParent, blockHash, reindexRoot)
+	if err != nil {
+		return err
+	}
+
+	// Add the block to the futureCoveringSets of all the blocks
+	// in the merget set
+	mergeSet := make([]*externalapi.DomainHash, len(ghostdagData.MergeSetBlues)+len(ghostdagData.MergeSetReds))
+	copy(mergeSet, ghostdagData.MergeSetBlues)
+	copy(mergeSet[len(ghostdagData.MergeSetBlues):], ghostdagData.MergeSetReds)
+
+	for _, current := range mergeSet {
+		err = rt.insertToFutureCoveringSet(current, blockHash)
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}

domain/consensus/processes/reachabilitymanager/stage.go

@@ -0,0 +1,66 @@
+package reachabilitymanager
+
+import (
+	"github.com/kaspanet/kaspad/domain/consensus/model"
+	"github.com/kaspanet/kaspad/domain/consensus/model/externalapi"
+)
+
+func (rt *reachabilityManager) stageData(blockHash *externalapi.DomainHash, data *model.ReachabilityData) {
+	rt.reachabilityDataStore.StageReachabilityData(blockHash, data)
+}
+
+func (rt *reachabilityManager) stageFutureCoveringSet(blockHash *externalapi.DomainHash, set model.FutureCoveringTreeNodeSet) error {
+	data, err := rt.data(blockHash)
+	if err != nil {
+		return err
+	}
+
+	data.FutureCoveringSet = set
+	rt.reachabilityDataStore.StageReachabilityData(blockHash, data)
+	return nil
+}
+
+func (rt *reachabilityManager) stageTreeNode(blockHash *externalapi.DomainHash, node *model.ReachabilityTreeNode) error {
+	data, err := rt.data(blockHash)
+	if err != nil {
+		return err
+	}
+
+	data.TreeNode = node
+	rt.reachabilityDataStore.StageReachabilityData(blockHash, data)
+	return nil
+}
+
+func (rt *reachabilityManager) stageReindexRoot(blockHash *externalapi.DomainHash) {
+	rt.reachabilityDataStore.StageReachabilityReindexRoot(blockHash)
+}
+
+func (rt *reachabilityManager) addChildAndStage(node, child *externalapi.DomainHash) error {
+	nodeData, err := rt.data(node)
+	if err != nil {
+		return err
+	}
+
+	nodeData.TreeNode.Children = append(nodeData.TreeNode.Children, child)
+	return rt.stageTreeNode(node, nodeData.TreeNode)
+}
+
+func (rt *reachabilityManager) stageParent(node, parent *externalapi.DomainHash) error {
+	treeNode, err := rt.treeNode(node)
+	if err != nil {
+		return err
+	}
+
+	treeNode.Parent = parent
+	return rt.stageTreeNode(node, treeNode)
+}
+
+func (rt *reachabilityManager) stageInterval(node *externalapi.DomainHash, interval *model.ReachabilityInterval) error {
+	treeNode, err := rt.treeNode(node)
+	if err != nil {
+		return err
+	}
+
+	treeNode.Interval = interval
+	return rt.stageTreeNode(node, treeNode)
+}

domain/consensus/processes/reachabilitytree/reachabilitytree.go

@@ -1,41 +0,0 @@
-package reachabilitytree
-
-import (
-	"github.com/kaspanet/kaspad/domain/consensus/model"
-	"github.com/kaspanet/kaspad/domain/consensus/model/externalapi"
-)
-
-// reachabilityTree maintains a structure that allows to answer
-// reachability queries in sub-linear time
-type reachabilityTree struct {
-	blockRelationStore    model.BlockRelationStore
-	reachabilityDataStore model.ReachabilityDataStore
-}
-
-// New instantiates a new ReachabilityTree
-func New(
-	blockRelationStore model.BlockRelationStore,
-	reachabilityDataStore model.ReachabilityDataStore) model.ReachabilityTree {
-	return &reachabilityTree{
-		blockRelationStore:    blockRelationStore,
-		reachabilityDataStore: reachabilityDataStore,
-	}
-}
-
-// AddBlock adds the block with the given blockHash into the reachability tree.
-func (rt *reachabilityTree) AddBlock(blockHash *externalapi.DomainHash) error {
-	return nil
-}
-
-// IsReachabilityTreeAncestorOf returns true if blockHashA is an
-// ancestor of blockHashB in the reachability tree. Note that this
-// does not necessarily mean that it isn't its ancestor in the DAG.
-func (rt *reachabilityTree) IsReachabilityTreeAncestorOf(blockHashA *externalapi.DomainHash, blockHashB *externalapi.DomainHash) (bool, error) {
-	return false, nil
-}
-
-// IsDAGAncestorOf returns true if blockHashA is an ancestor of
-// blockHashB in the DAG.
-func (rt *reachabilityTree) IsDAGAncestorOf(blockHashA *externalapi.DomainHash, blockHashB *externalapi.DomainHash) (bool, error) {
-	return false, nil
-}

infrastructure/logger/logger.go

@@ -54,6 +54,7 @@ var (
 	snvrLog = BackendLog.Logger("SNVR")
 	ibdsLog = BackendLog.Logger("IBDS")
 	wsvcLog = BackendLog.Logger("WSVC")
+	reacLog = BackendLog.Logger("REAC")
 )
 
 // SubsystemTags is an enum of all sub system tags
@@ -85,7 +86,8 @@ var SubsystemTags = struct {
 	DNSS,
 	SNVR,
 	IBDS,
-	WSVC string
+	WSVC,
+	REAC string
 }{
 	ADXR: "ADXR",
 	AMGR: "AMGR",
@@ -115,6 +117,7 @@ var SubsystemTags = struct {
 	SNVR: "SNVR",
 	IBDS: "IBDS",
 	WSVC: "WSVC",
+	REAC: "REAC",
 }
 
 // subsystemLoggers maps each subsystem identifier to its associated logger.
@@ -147,6 +150,7 @@ var subsystemLoggers = map[string]*Logger{
 	SubsystemTags.SNVR: snvrLog,
 	SubsystemTags.IBDS: ibdsLog,
 	SubsystemTags.WSVC: wsvcLog,
+	SubsystemTags.REAC: reacLog,
 }
 
 // InitLog attaches log file and error log file to the backend log.