Add optimistic status to chainhead (#10842)

* Add optimistic status to chainhead

* Fix tests

Co-authored-by: prylabs-bulldozer[bot] <58059840+prylabs-bulldozer[bot]@users.noreply.github.com>

beacon-chain/rpc/prysm/v1alpha1/beacon/blocks.go

@@ -393,6 +393,10 @@ func (bs *Server) chainHeadRetrieval(ctx context.Context) (*ethpb.ChainHead, err
 	if err != nil {
 		return nil, status.Error(codes.Internal, "Could not get head block")
 	}
+	optimisticStatus, err := bs.OptimisticModeFetcher.IsOptimistic(ctx)
+	if err != nil {
+		return nil, status.Error(codes.Internal, "Could not get optimistic status")
+	}
 	if err := wrapper.BeaconBlockIsNil(headBlock); err != nil {
 		return nil, status.Errorf(codes.NotFound, "Head block of chain was nil: %v", err)
 	}
@@ -474,5 +478,6 @@ func (bs *Server) chainHeadRetrieval(ctx context.Context) (*ethpb.ChainHead, err
 		PreviousJustifiedSlot:      pjSlot,
 		PreviousJustifiedEpoch:     prevJustifiedCheckpoint.Epoch,
 		PreviousJustifiedBlockRoot: prevJustifiedCheckpoint.Root,
+		OptimisticStatus:           optimisticStatus,
 	}, nil
 }

beacon-chain/rpc/prysm/v1alpha1/beacon/blocks_test.go

@@ -426,6 +426,7 @@ func TestServer_GetChainHead_NoGenesis(t *testing.T) {
 				FinalizedCheckPoint:         s.FinalizedCheckpoint(),
 				CurrentJustifiedCheckPoint:  s.CurrentJustifiedCheckpoint(),
 				PreviousJustifiedCheckPoint: s.PreviousJustifiedCheckpoint()},
+			OptimisticModeFetcher: &chainMock.ChainService{},
 		}
 		_, err = bs.GetChainHead(context.Background(), nil)
 		require.ErrorContains(t, "Could not get genesis block", err)
@@ -461,6 +462,7 @@ func TestServer_GetChainHead_NoFinalizedBlock(t *testing.T) {
 			FinalizedCheckPoint:         s.FinalizedCheckpoint(),
 			CurrentJustifiedCheckPoint:  s.CurrentJustifiedCheckpoint(),
 			PreviousJustifiedCheckPoint: s.PreviousJustifiedCheckpoint()},
+		OptimisticModeFetcher: &chainMock.ChainService{},
 	}
 
 	_, err = bs.GetChainHead(context.Background(), nil)
@@ -470,6 +472,7 @@ func TestServer_GetChainHead_NoFinalizedBlock(t *testing.T) {
 func TestServer_GetChainHead_NoHeadBlock(t *testing.T) {
 	bs := &Server{
 		HeadFetcher:           &chainMock.ChainService{Block: nil},
+		OptimisticModeFetcher: &chainMock.ChainService{},
 	}
 	_, err := bs.GetChainHead(context.Background(), nil)
 	assert.ErrorContains(t, "Head block of chain was nil", err)
@@ -533,6 +536,7 @@ func TestServer_GetChainHead(t *testing.T) {
 	bs := &Server{
 		BeaconDB:              db,
 		HeadFetcher:           &chainMock.ChainService{Block: wsb, State: s},
+		OptimisticModeFetcher: &chainMock.ChainService{},
 		FinalizationFetcher: &chainMock.ChainService{
 			FinalizedCheckPoint:         s.FinalizedCheckpoint(),
 			CurrentJustifiedCheckPoint:  s.CurrentJustifiedCheckpoint(),
@@ -550,6 +554,7 @@ func TestServer_GetChainHead(t *testing.T) {
 	assert.DeepEqual(t, pjRoot[:], head.PreviousJustifiedBlockRoot, "Unexpected PreviousJustifiedBlockRoot")
 	assert.DeepEqual(t, jRoot[:], head.JustifiedBlockRoot, "Unexpected JustifiedBlockRoot")
 	assert.DeepEqual(t, fRoot[:], head.FinalizedBlockRoot, "Unexpected FinalizedBlockRoot")
+	assert.Equal(t, false, head.OptimisticStatus)
 }
 
 func TestServer_StreamChainHead_ContextCanceled(t *testing.T) {
@@ -645,6 +650,7 @@ func TestServer_StreamChainHead_OnHeadUpdated(t *testing.T) {
 			FinalizedCheckPoint:         s.FinalizedCheckpoint(),
 			CurrentJustifiedCheckPoint:  s.CurrentJustifiedCheckpoint(),
 			PreviousJustifiedCheckPoint: s.PreviousJustifiedCheckpoint()},
+		OptimisticModeFetcher: &chainMock.ChainService{},
 	}
 	exitRoutine := make(chan bool)
 	ctrl := gomock.NewController(t)

beacon-chain/rpc/prysm/v1alpha1/beacon/server.go

@@ -47,4 +47,5 @@ type Server struct {
 	SyncChecker                 sync.Checker
 	ReplayerBuilder             stategen.ReplayerBuilder
 	HeadUpdater                 blockchain.HeadUpdater
+	OptimisticModeFetcher       blockchain.OptimisticModeFetcher
 }

beacon-chain/rpc/service.go

@@ -268,6 +268,7 @@ func (s *Service) Start() {
 		AttestationsPool:            s.cfg.AttestationsPool,
 		SlashingsPool:               s.cfg.SlashingsPool,
 		HeadUpdater:                 s.cfg.HeadUpdater,
+		OptimisticModeFetcher:       s.cfg.OptimisticModeFetcher,
 		HeadFetcher:                 s.cfg.HeadFetcher,
 		FinalizationFetcher:         s.cfg.FinalizationFetcher,
 		CanonicalFetcher:            s.cfg.CanonicalFetcher,

proto/prysm/v1alpha1/beacon_chain.proto

@@ -474,6 +474,9 @@ message ChainHead {
 
     // Previous 32 byte justified block root.
     bytes previous_justified_block_root = 12 [(ethereum.eth.ext.ssz_size) = "32"];
+
+    // Optimistic status of the current head
+    bool optimistic_status = 13;
 }
 
 message ListCommitteesRequest {