gui: vote slot message

Author: jherrera-jump

book/api/websocket.md

@@ -293,6 +293,14 @@ The largest slot for which the validator sent out a repair request.
 This slot has the same problem as `summary.turbine_slot` (it might
 sporadically become unboundedly large) and provides the same guarantees.
 
+#### `summary.vote_slot`
+| frequency       | type           | example |
+|-----------------|----------------|---------|
+| *Once* + *Live* | `number\|null` | `100`   |
+
+The most recent replayed slot this node was in the process of voting on.
+May be `null` at startup if voting has not started.
+
 #### `summary.caught_up_slot`
 | frequency       | type           | example |
 |-----------------|----------------|---------|

src/disco/gui/fd_gui.c

@@ -300,6 +300,7 @@ fd_gui_ws_open( fd_gui_t * gui,
     fd_gui_printf_optimistically_confirmed_slot,
     fd_gui_printf_completed_slot,
     fd_gui_printf_estimated_slot,
+    fd_gui_printf_vote_slot,
     fd_gui_printf_live_tile_timers,
     fd_gui_printf_catch_up_history,
   };
@@ -1834,6 +1835,12 @@ fd_gui_handle_reset_slot_legacy( fd_gui_t * gui,
     }
   }
 
+  if( FD_LIKELY( last_landed_vote!=ULONG_MAX && gui->summary.slot_voted!=last_landed_vote ) ) {
+    gui->summary.slot_voted = last_landed_vote;
+    fd_gui_printf_vote_slot( gui );
+    fd_http_server_ws_broadcast( gui->http );
+  }
+
   if( FD_UNLIKELY( gui->summary.vote_distance!=_slot-last_landed_vote ) ) {
     gui->summary.vote_distance = _slot-last_landed_vote;
     fd_gui_printf_vote_distance( gui );
@@ -2540,6 +2547,12 @@ fd_gui_handle_tower_update( fd_gui_t *                   gui,
                             long                         now ) {
   (void)now;
 
+  if( FD_LIKELY( tower->vote_slot!=ULONG_MAX && gui->summary.slot_voted!=tower->vote_slot ) ) {
+    gui->summary.slot_voted = tower->vote_slot;
+    fd_gui_printf_vote_slot( gui );
+    fd_http_server_ws_broadcast( gui->http );
+  }
+
   /* handle new root */
   if( FD_LIKELY( tower->root_slot!=ULONG_MAX && gui->summary.slot_rooted!=tower->root_slot ) ) {
     fd_gui_handle_rooted_slot( gui, tower->root_slot );

src/disco/gui/fd_gui.h

@@ -611,6 +611,7 @@ struct fd_gui {
     ulong bank_tile_cnt;
     ulong shred_tile_cnt;
 
+    ulong slot_voted;
     ulong slot_rooted;
     ulong slot_optimistically_confirmed;
     ulong slot_completed;

src/disco/gui/fd_gui_printf.c

@@ -242,6 +242,14 @@ fd_gui_printf_repair_slot( fd_gui_t * gui ) {
   jsonp_close_envelope( gui->http );
 }
 
+void
+fd_gui_printf_vote_slot( fd_gui_t * gui ) {
+  jsonp_open_envelope( gui->http, "summary", "vote_slot" );
+    if( FD_LIKELY( gui->summary.slot_voted!=ULONG_MAX  ) ) jsonp_ulong( gui->http, "value", gui->summary.slot_voted );
+    else                                                   jsonp_null ( gui->http, "value" );
+  jsonp_close_envelope( gui->http );
+}
+
 void
 fd_gui_printf_turbine_slot( fd_gui_t * gui ) {
   jsonp_open_envelope( gui->http, "summary", "turbine_slot" );

src/disco/gui/fd_gui_printf.h

@@ -17,6 +17,7 @@ void fd_gui_printf_vote_state( fd_gui_t * gui );
 void fd_gui_printf_vote_distance( fd_gui_t * gui );
 void fd_gui_printf_turbine_slot( fd_gui_t * gui );
 void fd_gui_printf_repair_slot( fd_gui_t * gui );
+void fd_gui_printf_vote_slot( fd_gui_t * gui );
 void fd_gui_printf_slot_caught_up( fd_gui_t * gui );
 void fd_gui_printf_skipped_history( fd_gui_t * gui );
 void fd_gui_printf_skipped_history_cluster( fd_gui_t * gui );