Feat: factored out eviction

pkg/protocol/chainmanagerv1/chain.go

@@ -1,6 +1,8 @@
 package chainmanagerv1
 
 import (
+	"fmt"
+
 	"github.com/iotaledger/hive.go/ds/reactive"
 	"github.com/iotaledger/hive.go/ds/shrinkingmap"
 	"github.com/iotaledger/hive.go/lo"
@@ -34,6 +36,8 @@ type Chain struct {
 	// warpSyncThreshold defines a lower bound for where the warp sync process starts (to not requests slots that we are
 	// about to commit ourselves once we are in sync).
 	warpSyncThreshold reactive.Variable[iotago.SlotIndex]
+
+	cumulativeWeight reactive.Variable[uint64]
 }
 
 func NewChain(forkingPoint *CommitmentMetadata) *Chain {
@@ -55,9 +59,25 @@ func NewChain(forkingPoint *CommitmentMetadata) *Chain {
 		return latestCommitmentIndex - WarpSyncOffset
 	}, c.latestCommitmentIndex)
 
+	c.cumulativeWeight = reactive.NewDerivedVariable[uint64](func(latestCommitmentIndex iotago.SlotIndex) uint64 {
+		if latestCommitment, exists := c.commitments.Get(latestCommitmentIndex); exists {
+			return latestCommitment.CumulativeWeight()
+		} else {
+			panic(fmt.Sprintf("latest commitment with index %d does not exist", latestCommitmentIndex))
+		}
+	}, c.latestCommitmentIndex)
+
 	return c
 }
 
+func (c *Chain) ForkingPoint() reactive.Variable[*CommitmentMetadata] {
+	return c.forkingPoint
+}
+
+func (c *Chain) LatestCommitmentIndex() reactive.Variable[iotago.SlotIndex] {
+	return c.latestCommitmentIndex
+}
+
 func (c *Chain) LatestVerifiedCommitmentIndex() reactive.Variable[iotago.SlotIndex] {
 	return c.latestVerifiedCommitmentIndex
 }

pkg/protocol/chainmanagerv1/chainmanager.go

@@ -23,22 +23,34 @@ type ChainManager struct {
 
 	commitmentRequester *eventticker.EventTicker[iotago.SlotIndex, iotago.CommitmentID]
 
-	slotEvictionEvents *shrinkingmap.ShrinkingMap[iotago.SlotIndex, reactive.Event]
-
-	lastEvictedSlotIndex reactive.Variable[iotago.SlotIndex]
+	*SlotEviction
 }
 
 func NewChainManager() *ChainManager {
 	return &ChainManager{
-		rootCommitment:       reactive.NewVariable[*CommitmentMetadata](),
-		commitmentCreated:    event.New1[*CommitmentMetadata](),
-		cachedCommitments:    shrinkingmap.New[iotago.CommitmentID, *promise.Promise[*CommitmentMetadata]](),
-		commitmentRequester:  eventticker.New[iotago.SlotIndex, iotago.CommitmentID](),
-		slotEvictionEvents:   shrinkingmap.New[iotago.SlotIndex, reactive.Event](),
-		lastEvictedSlotIndex: reactive.NewVariable[iotago.SlotIndex](),
+		rootCommitment:      reactive.NewVariable[*CommitmentMetadata](),
+		commitmentCreated:   event.New1[*CommitmentMetadata](),
+		cachedCommitments:   shrinkingmap.New[iotago.CommitmentID, *promise.Promise[*CommitmentMetadata]](),
+		commitmentRequester: eventticker.New[iotago.SlotIndex, iotago.CommitmentID](),
+
+		SlotEviction: NewSlotEviction(),
 	}
 }
 
+func (c *ChainManager) ProcessCommitment(commitment *model.Commitment) (commitmentMetadata *CommitmentMetadata) {
+	if commitmentRequest, _ := c.requestCommitment(commitment.ID(), commitment.Index(), false, func(resolvedMetadata *CommitmentMetadata) {
+		commitmentMetadata = resolvedMetadata
+	}); commitmentRequest != nil {
+		commitmentRequest.Resolve(NewCommitmentMetadata(commitment))
+	}
+
+	return commitmentMetadata
+}
+
+func (c *ChainManager) OnCommitmentCreated(callback func(commitment *CommitmentMetadata)) (unsubscribe func()) {
+	return c.commitmentCreated.Hook(callback).Unhook
+}
+
 func (c *ChainManager) SetRootCommitment(commitment *model.Commitment) (commitmentMetadata *CommitmentMetadata, err error) {
 	c.rootCommitment.Compute(func(currentRoot *CommitmentMetadata) *CommitmentMetadata {
 		if currentRoot != nil {
@@ -74,58 +86,6 @@ func (c *ChainManager) SetRootCommitment(commitment *model.Commitment) (commitme
 	return commitmentMetadata, nil
 }
 
-func (c *ChainManager) ProcessCommitment(commitment *model.Commitment) (commitmentMetadata *CommitmentMetadata) {
-	if commitmentRequest, _ := c.requestCommitment(commitment.ID(), commitment.Index(), false, func(resolvedMetadata *CommitmentMetadata) {
-		commitmentMetadata = resolvedMetadata
-	}); commitmentRequest != nil {
-		commitmentRequest.Resolve(NewCommitmentMetadata(commitment))
-	}
-
-	return commitmentMetadata
-}
-
-func (c *ChainManager) OnCommitmentCreated(callback func(commitment *CommitmentMetadata)) (unsubscribe func()) {
-	return c.commitmentCreated.Hook(callback).Unhook
-}
-
-func (c *ChainManager) SlotEvictedEvent(index iotago.SlotIndex) reactive.Event {
-	var slotEvictedEvent reactive.Event
-
-	c.lastEvictedSlotIndex.Compute(func(lastEvictedSlotIndex iotago.SlotIndex) iotago.SlotIndex {
-		if index > lastEvictedSlotIndex {
-			slotEvictedEvent, _ = c.slotEvictionEvents.GetOrCreate(index, reactive.NewEvent)
-		} else {
-			slotEvictedEvent = defaultTriggeredEvent
-		}
-
-		return lastEvictedSlotIndex
-	})
-
-	return slotEvictedEvent
-}
-
-func (c *ChainManager) Evict(slotIndex iotago.SlotIndex) {
-	slotEvictedEventsToTrigger := make([]reactive.Event, 0)
-
-	c.lastEvictedSlotIndex.Compute(func(lastEvictedSlotIndex iotago.SlotIndex) iotago.SlotIndex {
-		if slotIndex <= lastEvictedSlotIndex {
-			return lastEvictedSlotIndex
-		}
-
-		for i := lastEvictedSlotIndex + 1; i <= slotIndex; i++ {
-			if slotEvictedEvent, exists := c.slotEvictionEvents.Get(i); exists {
-				slotEvictedEventsToTrigger = append(slotEvictedEventsToTrigger, slotEvictedEvent)
-			}
-		}
-
-		return slotIndex
-	})
-
-	for _, slotEvictedEvent := range slotEvictedEventsToTrigger {
-		slotEvictedEvent.Trigger()
-	}
-}
-
 func (c *ChainManager) setupCommitment(commitment *CommitmentMetadata, slotEvictedEvent reactive.Event) {
 	c.requestCommitment(commitment.PrevID(), commitment.Index()-1, true, commitment.registerParent)
 
@@ -135,8 +95,8 @@ func (c *ChainManager) setupCommitment(commitment *CommitmentMetadata, slotEvict
 }
 
 func (c *ChainManager) requestCommitment(id iotago.CommitmentID, index iotago.SlotIndex, requestIfMissing bool, optSuccessCallbacks ...func(metadata *CommitmentMetadata)) (commitmentRequest *promise.Promise[*CommitmentMetadata], requestCreated bool) {
-	slotEvictedEvent := c.SlotEvictedEvent(index)
-	if slotEvictedEvent.WasTriggered() {
+	slotEvicted := c.EvictedEvent(index)
+	if slotEvicted.WasTriggered() {
 		if rootCommitment := c.rootCommitment.Get(); rootCommitment != nil && id == rootCommitment.ID() {
 			for _, successCallback := range optSuccessCallbacks {
 				successCallback(rootCommitment)
@@ -158,10 +118,10 @@ func (c *ChainManager) requestCommitment(id iotago.CommitmentID, index iotago.Sl
 				c.commitmentRequester.StopTicker(commitment.ID())
 			}
 
-			c.setupCommitment(commitment, slotEvictedEvent)
+			c.setupCommitment(commitment, slotEvicted)
 		})
 
-		slotEvictedEvent.OnTrigger(func() { c.cachedCommitments.Delete(id) })
+		slotEvicted.OnTrigger(func() { c.cachedCommitments.Delete(id) })
 	}
 
 	for _, successCallback := range optSuccessCallbacks {
@@ -170,9 +130,3 @@ func (c *ChainManager) requestCommitment(id iotago.CommitmentID, index iotago.Sl
 
 	return commitmentRequest, requestCreated
 }
-
-var defaultTriggeredEvent = reactive.NewEvent()
-
-func init() {
-	defaultTriggeredEvent.Trigger()
-}

pkg/protocol/chainmanagerv1/chainmanager_test.go

@@ -37,7 +37,7 @@ func TestChainManager(t *testing.T) {
 		commitment2.Index()+1,
 		commitment2.ID(),
 		commitment2.RootsID(),
-		2,
+		3,
 		2,
 	), testAPI)))
 
@@ -56,4 +56,5 @@ func TestChainManager(t *testing.T) {
 	require.True(t, commitment3Metadata.BelowSyncThreshold().Get())
 
 	require.Equal(t, iotago.SlotIndex(3), commitment3Metadata.Chain().Get().latestCommitmentIndex.Get())
+	require.Equal(t, uint64(3), commitment3Metadata.Chain().Get().cumulativeWeight.Get())
 }

pkg/protocol/chainmanagerv1/commitment_metadata.go

@@ -151,10 +151,6 @@ func (c *CommitmentMetadata) registerChild(newChild *CommitmentMetadata, onSucce
 	c.evicted.OnTrigger(c.chainSuccessor.OnUpdate(onSuccessorUpdated))
 }
 
-// inheritChain returns a function that implements the chain inheritance rules.
-//
-// It must be called whenever the successor of the parent changes as we spawn a new chain for each child that is not the
-// direct successor of a parent, and we inherit its chain otherwise.
 func (c *CommitmentMetadata) inheritChain(parent *CommitmentMetadata) func(*CommitmentMetadata, *CommitmentMetadata) {
 	var spawnedChain *Chain
 	spawnChain := func() {

pkg/protocol/chainmanagerv1/eviction.go

@@ -0,0 +1,66 @@
+package chainmanagerv1
+
+import (
+	"github.com/iotaledger/hive.go/ds/reactive"
+	"github.com/iotaledger/hive.go/ds/shrinkingmap"
+	iotago "github.com/iotaledger/iota.go/v4"
+)
+
+type SlotEviction struct {
+	evictionEvents *shrinkingmap.ShrinkingMap[iotago.SlotIndex, reactive.Event]
+
+	lastEvictedSlotIndex reactive.Variable[iotago.SlotIndex]
+}
+
+func NewSlotEviction() *SlotEviction {
+	return &SlotEviction{
+		evictionEvents:       shrinkingmap.New[iotago.SlotIndex, reactive.Event](),
+		lastEvictedSlotIndex: reactive.NewVariable[iotago.SlotIndex](),
+	}
+}
+
+func (c *SlotEviction) LastEvictedSlotIndex() reactive.Variable[iotago.SlotIndex] {
+	return c.lastEvictedSlotIndex
+}
+
+func (c *SlotEviction) EvictedEvent(index iotago.SlotIndex) reactive.Event {
+	slotEvictedEvent := defaultTriggeredEvent
+
+	c.lastEvictedSlotIndex.Compute(func(lastEvictedSlotIndex iotago.SlotIndex) iotago.SlotIndex {
+		if index > lastEvictedSlotIndex {
+			slotEvictedEvent, _ = c.evictionEvents.GetOrCreate(index, reactive.NewEvent)
+		}
+
+		return lastEvictedSlotIndex
+	})
+
+	return slotEvictedEvent
+}
+
+func (c *SlotEviction) Evict(slotIndex iotago.SlotIndex) {
+	slotEvictedEventsToTrigger := make([]reactive.Event, 0)
+
+	c.lastEvictedSlotIndex.Compute(func(lastEvictedSlotIndex iotago.SlotIndex) iotago.SlotIndex {
+		if slotIndex <= lastEvictedSlotIndex {
+			return lastEvictedSlotIndex
+		}
+
+		for i := lastEvictedSlotIndex + 1; i <= slotIndex; i++ {
+			if slotEvictedEvent, exists := c.evictionEvents.Get(i); exists {
+				slotEvictedEventsToTrigger = append(slotEvictedEventsToTrigger, slotEvictedEvent)
+			}
+		}
+
+		return slotIndex
+	})
+
+	for _, slotEvictedEvent := range slotEvictedEventsToTrigger {
+		slotEvictedEvent.Trigger()
+	}
+}
+
+var defaultTriggeredEvent = reactive.NewEvent()
+
+func init() {
+	defaultTriggeredEvent.Trigger()
+}