Handle genesis case for blocks/states at slot index

beacon-chain/blockchain/process_block.go

@@ -5,13 +5,13 @@ import (
 	"encoding/hex"
 	"fmt"
 
-	"github.com/prysmaticlabs/prysm/beacon-chain/state/stateutil"
 	"github.com/pkg/errors"
 	ethpb "github.com/prysmaticlabs/ethereumapis/eth/v1alpha1"
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/helpers"
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/state"
 	"github.com/prysmaticlabs/prysm/beacon-chain/flags"
 	stateTrie "github.com/prysmaticlabs/prysm/beacon-chain/state"
+	"github.com/prysmaticlabs/prysm/beacon-chain/state/stateutil"
 	"github.com/prysmaticlabs/prysm/shared/attestationutil"
 	"github.com/prysmaticlabs/prysm/shared/bytesutil"
 	"github.com/prysmaticlabs/prysm/shared/featureconfig"

beacon-chain/blockchain/receive_block.go

@@ -5,7 +5,6 @@ import (
 	"context"
 	"encoding/hex"
 
-	"github.com/prysmaticlabs/prysm/beacon-chain/state/stateutil"
 	"github.com/pkg/errors"
 	ethpb "github.com/prysmaticlabs/ethereumapis/eth/v1alpha1"
 	"github.com/prysmaticlabs/go-ssz"
@@ -14,6 +13,7 @@ import (
 	statefeed "github.com/prysmaticlabs/prysm/beacon-chain/core/feed/state"
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/helpers"
 	stateTrie "github.com/prysmaticlabs/prysm/beacon-chain/state"
+	"github.com/prysmaticlabs/prysm/beacon-chain/state/stateutil"
 	"github.com/prysmaticlabs/prysm/shared/featureconfig"
 	"github.com/prysmaticlabs/prysm/shared/traceutil"
 	"github.com/sirupsen/logrus"

beacon-chain/db/kv/blocks.go

@@ -360,6 +360,15 @@ func (k *Store) blocksAtSlotBitfieldIndex(ctx context.Context, tx *bolt.Tx, inde
 
 	highestSlot := index - 1
 	highestSlot = int(math.Max(0, float64(highestSlot)))
+
+	if highestSlot == 0 {
+		gBlock, err := k.GenesisBlock(ctx)
+		if err != nil {
+			return nil, err
+		}
+		return []*ethpb.SignedBeaconBlock{gBlock}, nil
+	}
+
 	f := filters.NewFilter().SetStartSlot(uint64(highestSlot)).SetEndSlot(uint64(highestSlot))
 
 	keys, err := getBlockRootsByFilter(ctx, tx, f)

beacon-chain/db/kv/blocks_test.go

@@ -508,6 +508,41 @@ func TestStore_SaveBlock_CanGetHighestAt(t *testing.T) {
 	}
 }
 
+func TestStore_GenesisBlock_CanGetHighestAt(t *testing.T) {
+	db := setupDB(t)
+	defer teardownDB(t, db)
+	ctx := context.Background()
+
+	genesisBlock := &ethpb.SignedBeaconBlock{Block: &ethpb.BeaconBlock{}}
+	genesisRoot, _ := ssz.HashTreeRoot(genesisBlock.Block)
+	db.SaveGenesisBlockRoot(ctx, genesisRoot)
+	db.SaveBlock(ctx, genesisBlock)
+	block1 := &ethpb.SignedBeaconBlock{Block: &ethpb.BeaconBlock{Slot: 1}}
+	db.SaveBlock(ctx, block1)
+
+	highestAt, err := db.HighestSlotBlocksBelow(ctx, 2)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !proto.Equal(block1, highestAt[0]) {
+		t.Errorf("Wanted %v, received %v", block1, highestAt)
+	}
+	highestAt, err = db.HighestSlotBlocksBelow(ctx, 1)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !proto.Equal(genesisBlock, highestAt[0]) {
+		t.Errorf("Wanted %v, received %v", genesisBlock, highestAt)
+	}
+	highestAt, err = db.HighestSlotBlocksBelow(ctx, 0)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !proto.Equal(genesisBlock, highestAt[0]) {
+		t.Errorf("Wanted %v, received %v", genesisBlock, highestAt)
+	}
+}
+
 func TestStore_SaveBlocks_CanGetHighest(t *testing.T) {
 	db := setupDB(t)
 	defer teardownDB(t, db)

beacon-chain/db/kv/state.go

@@ -392,6 +392,15 @@ func (k *Store) statesAtSlotBitfieldIndex(ctx context.Context, tx *bolt.Tx, inde
 
 	highestSlot := index - 1
 	highestSlot = int(math.Max(0, float64(highestSlot)))
+
+	if highestSlot == 0 {
+		gState, err := k.GenesisState(ctx)
+		if err != nil {
+			return nil, err
+		}
+		return []*state.BeaconState{gState}, nil
+	}
+
 	f := filters.NewFilter().SetStartSlot(uint64(highestSlot)).SetEndSlot(uint64(highestSlot))
 
 	keys, err := getBlockRootsByFilter(ctx, tx, f)

beacon-chain/db/kv/state_test.go

@@ -447,3 +447,54 @@ func TestStore_SaveDeleteState_CanGetHighestBelow(t *testing.T) {
 		t.Errorf("Did not retrieve saved state: %v != %v", highest, s2)
 	}
 }
+
+func TestStore_GenesisState_CanGetHighestBelow(t *testing.T) {
+	db := setupDB(t)
+	defer teardownDB(t, db)
+
+	s := &pb.BeaconState{}
+	genesisState, err := state.InitializeFromProto(s)
+	if err != nil {
+		t.Fatal(err)
+	}
+	genesisRoot := [32]byte{'a'}
+	db.SaveGenesisBlockRoot(context.Background(), genesisRoot)
+	db.SaveState(context.Background(), genesisState, genesisRoot)
+
+	s0 := &pb.BeaconState{Slot: 1}
+	b := &ethpb.SignedBeaconBlock{Block: &ethpb.BeaconBlock{Slot: 1}}
+	r, _ := ssz.HashTreeRoot(b.Block)
+	if err := db.SaveBlock(context.Background(), b); err != nil {
+		t.Fatal(err)
+	}
+	st, err := state.InitializeFromProto(s0)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := db.SaveState(context.Background(), st, r); err != nil {
+		t.Fatal(err)
+	}
+
+	highest, err := db.HighestSlotStatesBelow(context.Background(), 2)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !proto.Equal(highest[0].InnerStateUnsafe(), s0) {
+		t.Errorf("Did not retrieve saved state: %v != %v", highest, s0)
+	}
+
+	highest, err = db.HighestSlotStatesBelow(context.Background(), 1)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !proto.Equal(highest[0].InnerStateUnsafe(), genesisState.InnerStateUnsafe()) {
+		t.Errorf("Did not retrieve saved state: %v != %v", highest, s0)
+	}
+	highest, err = db.HighestSlotStatesBelow(context.Background(), 0)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !proto.Equal(highest[0].InnerStateUnsafe(), genesisState.InnerStateUnsafe()) {
+		t.Errorf("Did not retrieve saved state: %v != %v", highest, s0)
+	}
+}

beacon-chain/rpc/beacon/blocks.go

@@ -4,7 +4,6 @@ import (
 	"context"
 	"strconv"
 
-	"github.com/prysmaticlabs/prysm/beacon-chain/state/stateutil"
 	ptypes "github.com/gogo/protobuf/types"
 	ethpb "github.com/prysmaticlabs/ethereumapis/eth/v1alpha1"
 	"github.com/prysmaticlabs/go-ssz"
@@ -14,6 +13,7 @@ import (
 	"github.com/prysmaticlabs/prysm/beacon-chain/core/helpers"
 	"github.com/prysmaticlabs/prysm/beacon-chain/db/filters"
 	"github.com/prysmaticlabs/prysm/beacon-chain/flags"
+	"github.com/prysmaticlabs/prysm/beacon-chain/state/stateutil"
 	"github.com/prysmaticlabs/prysm/shared/bytesutil"
 	"github.com/prysmaticlabs/prysm/shared/pagination"
 	"google.golang.org/grpc/codes"

slasher/rpc/server.go

@@ -3,12 +3,12 @@ package rpc
 import (
 	"context"
 
-	"github.com/prysmaticlabs/prysm/slasher/db"
-	log "github.com/sirupsen/logrus"
 	"github.com/pkg/errors"
 	ethpb "github.com/prysmaticlabs/ethereumapis/eth/v1alpha1"
 	slashpb "github.com/prysmaticlabs/prysm/proto/slashing"
+	"github.com/prysmaticlabs/prysm/slasher/db"
 	"github.com/prysmaticlabs/prysm/slasher/detection"
+	log "github.com/sirupsen/logrus"
 	"go.opencensus.io/trace"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/status"

slasher/rpc/service.go

@@ -5,13 +5,13 @@ import (
 	"fmt"
 	"net"
 
-	"github.com/prysmaticlabs/prysm/slasher/db"
 	middleware "github.com/grpc-ecosystem/go-grpc-middleware"
 	recovery "github.com/grpc-ecosystem/go-grpc-middleware/recovery"
 	grpc_opentracing "github.com/grpc-ecosystem/go-grpc-middleware/tracing/opentracing"
 	grpc_prometheus "github.com/grpc-ecosystem/go-grpc-prometheus"
 	slashpb "github.com/prysmaticlabs/prysm/proto/slashing"
 	"github.com/prysmaticlabs/prysm/shared/traceutil"
+	"github.com/prysmaticlabs/prysm/slasher/db"
 	"github.com/prysmaticlabs/prysm/slasher/detection"
 	log "github.com/sirupsen/logrus"
 	"go.opencensus.io/plugin/ocgrpc"