API: Add support for retrieving user names for all layers

(cherry picked from commit 3514d130cb)

Co-authored-by: Jon Evans <[email protected]>

pcbnew/api/api_handler_pcb.cpp

@@ -97,6 +97,7 @@ API_HANDLER_PCB::API_HANDLER_PCB( PCB_EDIT_FRAME* aFrame ) :
             &API_HANDLER_PCB::handleExpandTextVariables );
     registerHandler<GetBoardOrigin, types::Vector2>( &API_HANDLER_PCB::handleGetBoardOrigin );
     registerHandler<SetBoardOrigin, Empty>( &API_HANDLER_PCB::handleSetBoardOrigin );
+    registerHandler<GetBoardLayerName, BoardLayerNameResponse>( &API_HANDLER_PCB::handleGetBoardLayerName );
 
     registerHandler<InteractiveMoveItems, Empty>( &API_HANDLER_PCB::handleInteractiveMoveItems );
     registerHandler<GetNets, NetsResponse>( &API_HANDLER_PCB::handleGetNets );
@@ -1172,6 +1173,25 @@ HANDLER_RESULT<Empty> API_HANDLER_PCB::handleSetBoardOrigin(
 }
 
 
+HANDLER_RESULT<BoardLayerNameResponse> API_HANDLER_PCB::handleGetBoardLayerName(
+            const HANDLER_CONTEXT<GetBoardLayerName>& aCtx )
+{
+    if( HANDLER_RESULT<bool> documentValidation = validateDocument( aCtx.Request.board() );
+        !documentValidation )
+    {
+        return tl::unexpected( documentValidation.error() );
+    }
+
+    BoardLayerNameResponse response;
+
+    PCB_LAYER_ID id = FromProtoEnum<PCB_LAYER_ID>( aCtx.Request.layer() );
+
+    response.set_name( frame()->GetBoard()->GetLayerName( id ) );
+
+    return response;
+}
+
+
 HANDLER_RESULT<GetBoundingBoxResponse> API_HANDLER_PCB::handleGetBoundingBox(
         const HANDLER_CONTEXT<GetBoundingBox>& aCtx )
 {