AutoMapper ignores MaxDepth when foreign key entity is of the same type

Question

I am trying to get AutoMapper to only map the first level of an Entity, so I set MaxDepth(1), which works great, except for my Menu entity which has a property called ParentMenu that is also of type Menu.

Startup.cs

public IServiceProvider ConfigureServices(IServiceCollection services)
{
    services
      ...
      ...
      .AddAutoMapper(config =>
      {
        config.AddProfiles(typeof(Startup).Assembly);
        config.ForAllMaps((cfg, expr) =>
        {
           if (typeof(Entity).IsAssignableFrom(cfg.DestinationType))
           {
              expr.MaxDepth(1);
           }
        });
        config.CreateMissingTypeMaps = true;
        config.ValidateInlineMaps = false;
      });
   ...
   ...
}

Menu.cs

public class Menu : Entity
{
  int Id {get; set;}
  string Name {get; set;}
  int ParentMenuId {get; set;}
  Menu ParentMenu {get; set;}
  int ModuleId {get; set;}
  Module Module {get; set;}
}

MenuViewModel.cs

public class MenuViewModel
{
  int Id {get; set;}
  string Name {get; set;}
  int ParentMenuId {get; set;}
  string ParentMenuName {get; set;}
  int ModuleId {get; set;}
  string ModuleName {get; set;}
}

MenuController.cs

public IActionResult Edit(MenuViewModel viewModel)
{
  var model = EditGetModel(id); // returns the Menu Entity
  Mapper.Map(viewModel, model);
  // model.ParentMenuId is set properly
  // model.ParentMenu set to a new instance of Menu ignoring MaxDepth(1)
  // model.ModuleId is set properly
  // model.Module is properly left null
  ...
  ...
}

I can't figure out why MaxDepth(1) is ignored when an Entity has a property of the same type, any help would be greatly appreciated.

Answer 1

This doesn't seem to have anything to do with depth or recursion. It's also not clear what the exact problem is. The code you have is mapping a view model onto an entity. If I had to guess, I'd imagine the issue is that AutoMapper is creating a new Menu instance and replacing the existing ParentMenu property on your entity with that. The reason is that you're projecting ParentMenuName , which will map to ParentMenu.Name on the entity. You should ignore ParentMenu in the mapping:

CreateMap<MenuViewModel, Menu>()
    ...
    .ForMember(dest => dest.ParentMenu, opts => opts.Ignore());