[flow] more logging around indexing during startup

Summary: Changelog: [internal]

Reviewed By: SamChou19815

Differential Revision:
D69668538

------------------------------------------------------------------------
(from 9d3940bf19943d301dcbcf29cd34b3ea8ead8ff8)

fbshipit-source-id: be098081701ef866fc17886182bee0f12efc7d3f

src/services/export/export_service.ml

@@ -333,6 +333,7 @@ let index ~workers ~reader parsed :
     (exports_to_add, exports_to_remove, imports_to_add, imports_to_remove, count)
   in
 
+  Hh_logger.info "Indexing files: creating index...";
   MonitorRPC.status_update
     ~event:ServerStatus.(Indexing_progress { finished = 0; total = Some total_count });
   (* each job returns two Export_index.t's. we cons them onto lists and merge them all
@@ -363,6 +364,7 @@ let index ~workers ~reader parsed :
         ))
       ~next:(MultiWorkerLwt.next workers parsed)
   in
+  Hh_logger.info "Indexing files: indexing post-process...";
   MonitorRPC.status_update ~event:ServerStatus.Indexing_post_process;
 
   let exports_to_add =
@@ -396,9 +398,12 @@ let init ~workers ~reader ~libs parsed =
   let%lwt (exports_to_add, _exports_to_remove, imports_to_add, _imports_to_remove) =
     index ~workers ~reader parsed
   in
+  Hh_logger.info "Indexing files: adding exports of builtins...";
   let exports_to_add = add_exports_of_builtins libs exports_to_add in
+  Hh_logger.info "Indexing files: merging exports-imports...";
   let final_export_index = Export_index.merge_export_import imports_to_add exports_to_add in
   (* TODO: assert that _exports_to_remove is empty? should be on init *)
+  Hh_logger.info "Indexing files: initing...";
   let search = Export_search.init final_export_index in
   MonitorRPC.status_update ~event:ServerStatus.Indexing_end;
   Lwt.return search

src/services/inference/types_js.ml

@@ -1828,6 +1828,7 @@ let init_with_initial_state
         Export_service.init ~workers ~reader ~libs:lib_exports parsed
     )
   in
+  Hh_logger.info "Finished indexing files";
 
   let connections =
     Base.Option.value_map
@@ -2226,7 +2227,7 @@ let init_from_scratch ~profiling ~workers options =
         Export_service.init ~workers ~reader ~libs:lib_exports parsed_set
     )
   in
-  Hh_logger.info "Done";
+  Hh_logger.info "Finished indexing files";
 
   let (collated_errors, _) =
     ErrorCollator.update_local_collated_errors