Implement slot fetching and caching from CL

beacon/goclient/attest.go

@@ -13,6 +13,7 @@ import (
 	"github.com/attestantio/go-eth2-client/spec"
 	"github.com/attestantio/go-eth2-client/spec/phase0"
 	"github.com/jellydator/ttlcache/v3"
+	"github.com/ssvlabs/ssv/logging/fields"
 	"go.uber.org/zap"
 )
 
@@ -299,19 +300,57 @@ func (gc *GoClient) scoreAttestationData(ctx context.Context,
 	// Initial score is based on height of source and target epochs.
 	score := float64(attestationData.Source.Epoch + attestationData.Target.Epoch)
 
-	//TODO: add slot values to equation. Implement cache
+	// Increase score based on the nearness of the head slot.
+	slot, err := gc.blockRootToSlot(ctx, attestationData.BeaconBlockRoot)
+	if err != nil {
+		gc.log.
+			With(zap.Error(err), fields.BlockRoot(attestationData.BeaconBlockRoot)).
+			Error("failed to obtain slot for block root")
+		slot = 0
+	} else {
+		score += float64(1) / float64(1+attestationData.Slot-slot)
+	}
 
 	gc.log.
 		With(zap.String("client_addr", addr)).
 		With(zap.Uint64("attestation_slot", uint64(attestationData.Slot))).
 		With(zap.Uint64("source_epoch", uint64(attestationData.Source.Epoch))).
 		With(zap.Uint64("target_epoch", uint64(attestationData.Target.Epoch))).
 		With(zap.Float64("score", score)).
-		Info("scored attestation data")
+		Debug("scored attestation data")
 
 	return score
 }
 
+func (gc *GoClient) blockRootToSlot(ctx context.Context, root phase0.Root) (phase0.Slot, error) {
+	gc.blockRootToSlotMu.RLock()
+	slot, exists := gc.blockRootToSlotCache[root]
+	gc.blockRootToSlotMu.RUnlock()
+	if exists {
+		gc.log.
+			With(fields.BlockRoot(root)).
+			With(fields.Slot(slot)).
+			Debug("obtained slot from cache")
+		return slot, nil
+	}
+
+	gc.log.Debug("slot was not found in cache. Fetching from Consensus Client")
+	blockResponse, err := gc.multiClient.BeaconBlockHeader(ctx, &api.BeaconBlockHeaderOpts{
+		Block: root.String(),
+	})
+	if err != nil {
+		return 0, errors.Join(err, errors.New("failed to obtain block header"))
+	}
+
+	gc.log.Debug("slot was fetched from Consensus Client")
+
+	gc.blockRootToSlotMu.Lock()
+	gc.blockRootToSlotCache[root] = blockResponse.Data.Header.Message.Slot
+	gc.blockRootToSlotMu.Unlock()
+
+	return blockResponse.Data.Header.Message.Slot, nil
+}
+
 // withCommitteeIndex returns a deep copy of the attestation data with the provided committee index set.
 func withCommitteeIndex(data *phase0.AttestationData, committeeIndex phase0.CommitteeIndex) (*phase0.AttestationData, error) {
 	// Marshal & unmarshal to make a deep copy. This is safer because it won't break silently if

beacon/goclient/goclient.go

@@ -100,6 +100,7 @@ type MultiClient interface {
 	eth2client.BeaconBlockRootProvider
 	eth2client.SyncCommitteeContributionProvider
 	eth2client.SyncCommitteeContributionsSubmitter
+	eth2client.BeaconBlockHeadersProvider
 	eth2client.ValidatorsProvider
 	eth2client.ProposalPreparationsSubmitter
 	eth2client.EventsProvider
@@ -126,6 +127,8 @@ type GoClient struct {
 	registrationLastSlot phase0.Slot
 	registrationCache    map[phase0.BLSPubKey]*api.VersionedSignedValidatorRegistration
 
+	blockRootToSlotMu    sync.RWMutex
+	blockRootToSlotCache map[phase0.Root]phase0.Slot
 	// attestationReqInflight helps prevent duplicate attestation data requests
 	// from running in parallel.
 	attestationReqInflight singleflight.Group[phase0.Slot, *phase0.AttestationData]