I was looking through some code in an ASP.NET Core application and I noticed the repository services are added with AddScope, while in mine i am using addTransient. I have looked about the difference but i still do not understand how would this change my actual applicationn.
this is the code i am using and the services i use on pages for Get / Post actions.
services.AddHttpContextAccessor(); services.AddSingleton<IFileProvider>(new PhysicalFileProvider(Path.Combine(Directory.GetCurrentDirectory(), "wwwroot/files"))); services.AddTransient<IAuthorizationHandler, HasArranqueActivoHandler>(); services.AddTransient<IAuthorizationHandler, HasArranqueInactivoHandler>(); services.AddTransient<IAuthorizationHandler, IsParagemNotOnGoingHandler>(); services.AddTransient<IAuthorizationHandler, IsParagemOnGoingHandler>(); services.AddTransient<Services.Interfaces.IUserService, Services.UserService>(); #region AreaProduction services.AddTransient<Production.Interfaces.IComponenteService, Production.ComponenteService>(); services.AddTransient<Production.Interfaces.IReferenciaService, Production.ReferenciaService>(); services.AddTransient<Production.Interfaces.IProducaoRegistoService, Production.ProducaoRegistoService>(); services.AddTransient<Production.Interfaces.IParagemService, Production.ParagemService>(); services.AddTransient<Production.Interfaces.ICelulaService, Production.CelulaService>(); services.AddTransient<Production.Interfaces.IUapService, Production.UapService>(); services.AddTransient<Production.Interfaces.ICelulaTipoService, CelulaTipoService>(); services.AddTransient<Production.Interfaces.IMatrizService, MatrizService>(); services.AddTransient<Production.Interfaces.IOperadorService, Production.OperadorService>(); services.AddTransient<Production.Interfaces.IEtiquetaService, Production.EtiquetaService>(); services.AddTransient<Production.Interfaces.IPokayokeService, Production.PokayokeService>(); services.AddTransient<Production.Interfaces.IGeometriaService, Production.GeometriaService>(); services.AddTransient<Production.Interfaces.IEmpregadoService, Production.EmpregadoService>(); services.AddTransient<Production.Interfaces.IPecaService, Production.PecaService>(); services.AddTransient<Production.Interfaces.IDefeitoService, Production.DefeitoService>(); #endregion #region AreaRobotics services.AddTransient<Robotics.Interfaces.ITurnoService, Robotics.TurnoService>(); services.AddTransient<Robotics.Interfaces.ICelulaService, Robotics.CelulaService>(); services.AddTransient<Robotics.Interfaces.ICheckListService, Robotics.CheckListService>(); services.AddTransient<Robotics.Interfaces.IProducaoService, Robotics.ProducaoService>(); services.AddTransient<Robotics.Interfaces.IReferenciaService, Robotics.ReferenciaService>(); services.AddTransient<Robotics.Interfaces.IDefeitoService, Robotics.DefeitoService>(); services.AddTransient<Robotics.Interfaces.IDefeitoCodigoService, Robotics.DefeitoCodigoService>(); services.AddTransient<Robotics.Interfaces.IParagemService, Robotics.ParagemService>(); services.AddTransient<Robotics.Interfaces.IParagemCodigoService, Robotics.ParagemCodigoService>(); services.AddTransient<Robotics.Interfaces.IPecaService, Robotics.PecaService>(); services.AddTransient<Robotics.Interfaces.IUapService, Robotics.UapService>(); services.AddTransient<Robotics.Interfaces.IOperadorService, Robotics.OperadorService>(); #endregion #region AreaRobotics services.AddTransient<Areas.Robotics.Services.Interfaces.ITurnoService, Areas.Robotics.Services.TurnoService>(); services.AddTransient<Areas.Robotics.Services.Interfaces.ICelulaService, Areas.Robotics.Services.CelulaService>(); services.AddTransient<Areas.Robotics.Services.Interfaces.ICheckListService, Areas.Robotics.Services.CheckListService>(); services.AddTransient<Areas.Robotics.Services.Interfaces.IProducaoService, Areas.Robotics.Services.ProducaoService>(); services.AddTransient<Areas.Robotics.Services.Interfaces.IReferenciaService, Areas.Robotics.Services.ReferenciaService>(); services.AddTransient<Areas.Robotics.Services.Interfaces.IDefeitoService, Areas.Robotics.Services.DefeitoService>(); services.AddTransient<Areas.Robotics.Services.Interfaces.IDefeitoCodigoService, Areas.Robotics.Services.DefeitoCodigoService>(); services.AddTransient<Areas.Robotics.Services.Interfaces.IParagemService, Areas.Robotics.Services.ParagemService>(); services.AddTransient<Areas.Robotics.Services.Interfaces.IParagemCodigoService, Areas.Robotics.Services.ParagemCodigoService>(); services.AddTransient<Areas.Robotics.Services.Interfaces.IPecaService, Areas.Robotics.Services.PecaService>(); services.AddTransient<Areas.Robotics.Services.Interfaces.IUapService, Areas.Robotics.Services.UapService>(); services.AddTransient<Areas.Robotics.Services.Interfaces.IOperadorService, Areas.Robotics.Services.OperadorService>(); #endregion I would like to know what the impact of changing from AddTransient to AddScoped for my services in my application
Here is a simple Create page with many transient Services to populate select lists
public class CreateModel : PageModel { private readonly IMatrizService _matrizService; private readonly IReferenciaService _referenciaService; private readonly IUapService _uapService; private readonly ICelulaTipoService _celulaTipoService; private readonly ICelulaService _celulaService; private readonly IToastNotification _toastNotification; private readonly ILogger<CreateModel> _logger; public CreateModel(IToastNotification toastNotification, ICelulaTipoService celulaTipoService, ICelulaService celulaService, IUapService uapService, IReferenciaService referenciaService, IMatrizService matrizService, ILogger<CreateModel> logger) { _matrizService = matrizService; _referenciaService = referenciaService; _uapService = uapService; _celulaTipoService = celulaTipoService; _celulaService = celulaService; _toastNotification = toastNotification; _logger = logger; } [BindProperty] public Matriz Matriz { get; set; } public void OnGet() { ViewData["CelulaId"] = new SelectList(_celulaService.GetAllFromCache(), "Id", "Nome"); ViewData["UAPId"] = new SelectList(_uapService.GetAllFromCache(), "Id", "Nome"); ViewData["ReferenciaId"] = new SelectList(_referenciaService.GetAllFromCache(), "Id", "Nome"); } public async Task<IActionResult> OnPostAsync() { if (!ModelState.IsValid) { ViewData["CelulaId"] = new SelectList(_celulaService.GetAllFromCache(), "Id", "Nome"); ViewData["UAPId"] = new SelectList(_uapService.GetAllFromCache(), "Id", "Nome"); ViewData["ReferenciaId"] = new SelectList(_referenciaService.GetAllFromCache(), "Id", "Nome"); _toastNotification.AddErrorToastMessage("Falha ao criar Matriz. Verifique os dados novamente."); return Page(); } _matrizService.Add(Matriz); try { await _matrizService.SaveChangesAsync(); } catch (DbUpdateException e) { //This either returns a error string, or null if it can’t handle that error _logger.LogError($@"Falha ao Adicionar Referência Area: Administration Page: Account/Robotics/Referencias/Create Error: {e.InnerException}"); _toastNotification.AddErrorToastMessage($"A Matriz com a Referência {Matriz.Referencia.Nome} já existe"); return Page(); } _toastNotification.AddSuccessToastMessage("Matriz criada com sucesso."); return RedirectToPage("./Index"); } } Most of my services are usually the same with crud methods
public interface IUserService { IQueryable<User> GetAll(); User GetById(int id); void Add(User user); void Update(User user); int AddAndSave(User user); int SaveChanges(); int UpdateDateAndSave(User user); User GetByUsername(string username); } public class UserService : IUserService { private readonly DatabaseContext _context; public UserService(DatabaseContext context) { _context = context; } public void Add(User user) { _context.Users.Add(user); } public int AddAndSave(User user) { _context.Users.Add(user); return _context.SaveChanges(); } public IQueryable<User> GetAll() { return _context.Users.AsNoTracking(); } public User GetById(int id) { return _context.Users.Find(id); } public User GetByUsername(string username) { return _context.Users .Include(u => u.Colaborador) .Include(u => u.UserRoles) .ThenInclude(ur => ur.Role) .AsNoTracking() .FirstOrDefault(u => u.Username == username); } public int SaveChanges() { return _context.SaveChanges(); } public void Update(User user) { _context.Users.Update(user); } public int UpdateDateAndSave(User user) { user.DataSessao = DateTime.Now; _context.Users.Attach(user); _context.Entry(user).Property(u => u.DataSessao).IsModified = true; return _context.SaveChanges(); } } 
AddScoped) are created once per client request (connection). Transient lifetime services (AddTransient) are created each time they're requested from the service container. What is your actual question?using Areas.Robotics.Services;to this file, it would make the code a little more readable :)