intercept and init nil [][]byte transaction slices

beacon-chain/powchain/execution_engine.go

@@ -168,10 +168,6 @@ func (s *Service) GetPayload(ctx context.Context, payloadID uint64) (*catalyst.E
 // Engine API definition:
 // 	https://github.com/ethereum/execution-apis/blob/main/src/engine/specification.md#engine_executepayloadv1
 func (s *Service) ExecutePayload(ctx context.Context, data *catalyst.ExecutableDataV1) ([]byte, error) {
-	// TODO: Fix this. Somehow transactions becomes nil with grpc call server->client
-	if data.Transactions == nil {
-		data.Transactions = [][]byte{}
-	}
 	reqBody := &EngineRequest{
 		JsonRPC: "2.0",
 		Method:  "engine_executePayloadV1",

beacon-chain/rpc/prysm/v1alpha1/validator/proposer.go

@@ -55,6 +55,8 @@ func (vs *Server) GetBeaconBlock(ctx context.Context, req *ethpb.BlockRequest) (
 		return nil, status.Errorf(codes.Internal, "Could not fetch Merge beacon block: %v", err)
 	}
 
+	log.Info("Sending block to client, transaction field is nil: ", blk.Body.ExecutionPayload.Transactions == nil)
+
 	return &ethpb.GenericBeaconBlock{Block: &ethpb.GenericBeaconBlock_Merge{Merge: blk}}, nil
 }
 

validator/client/propose.go

@@ -572,6 +572,8 @@ func (v *validator) proposeBlockMerge(ctx context.Context, slot types.Slot, pubK
 		RandaoReveal: randaoReveal,
 		Graffiti:     g,
 	})
+
+	log.Info("Received block from server, transaction field is nil: ", b.GetMerge().Body.ExecutionPayload.Transactions == nil)
 	if err != nil {
 		log.WithField("blockSlot", slot).WithError(err).Error("Failed to request block from beacon node")
 		if v.emitAccountMetrics {

validator/client/service.go

@@ -259,6 +259,29 @@ func (v *ValidatorService) recheckKeys(ctx context.Context) {
 	}
 }
 
+
+func fixNilTransactions(ctx context.Context, method string, req, reply interface{}, cc *grpc.ClientConn, invoker grpc.UnaryInvoker, opts ...grpc.CallOption) error {
+	err := invoker(ctx, method, req, reply, cc, opts...)
+	if err != nil {
+		return err
+	}
+	if method == "/ethereum.eth.v1alpha1.BeaconNodeValidator/GetBeaconBlock" {
+		rp := reply.(*ethpb.GenericBeaconBlock)
+		mb := rp.GetMerge()
+		// not a merge block
+		if mb == nil {
+			return nil
+		}
+		if mb.Body.ExecutionPayload.Transactions == nil {
+			mb.Body.ExecutionPayload.Transactions = make([][]byte, 0)
+			reply = ethpb.GenericBeaconBlock{
+				Block: &ethpb.GenericBeaconBlock_Merge{Merge: mb},
+			}
+		}
+	}
+	return nil
+}
+
 // ConstructDialOptions constructs a list of grpc dial options
 func ConstructDialOptions(
 	maxCallRecvMsgSize int,
@@ -299,6 +322,7 @@ func ConstructDialOptions(
 			grpc_prometheus.UnaryClientInterceptor,
 			grpc_retry.UnaryClientInterceptor(),
 			grpcutil.LogRequests,
+			fixNilTransactions,
 		)),
 		grpc.WithChainStreamInterceptor(
 			grpcutil.LogStream,