How to get current userId in asp.net core

Question

I use Identity in core.

in startup.

services.AddSingleton<ICurrentUserService, CurrentUserService>();
services.AddHttpContextAccessor();

and in accountcontroller

[ApiController]
[Route("api/[controller]")]
public class AccountController : Controller
{
 private readonly IApplicationUserManager _userManager;
 private readonly SignInManager<ApplicationUser> _signInManager;
 public AccountController
 (IApplicationUserManager userManager,
 SignInManager<ApplicationUser> signInManager)
 {
 _userManager = userManager;
 //_roleManager = roleManager;
 _signInManager = signInManager;
 }
 [HttpPost("Login")]
 [AllowAnonymous]
 public async Task<IActionResult> Login(LoginViewModel model)
 {
 try
 {
 await _signInManager.SignOutAsync();
 var result = await _signInManager.PasswordSignInAsync(model.email, model.password, true, false);
 if (result.Succeeded)
 {
 return Json(new { success = true});
 }
 var message = string.Join("; ", ModelState.Values
 .SelectMany(x => x.Errors)
 .Select(x => x.ErrorMessage));
 return Json(new
 {
 success = false,
 Message = message
 });
 }
 catch (Exception e)
 {
 return Json(new
 {
 success = false,
 Message = e.Message
 });
 }
 }
 [HttpPost("logout")]
 public IActionResult LogOut()
 {
 try
 {
 _signInManager.SignOutAsync();
 return Ok(new { success = true });
 }
 catch (Exception e)
 {
 return Ok(new { success = false, Message = e.Message });
 }
 }
}

}

and in CurrentUserService

public class CurrentUserService : ICurrentUserService
{
private readonly IHttpContextAccessor _httpContextAccessor;
public CurrentUserService(IHttpContextAccessor httpContextAccessor)
{
 _httpContextAccessor = httpContextAccessor;
}
public Guid? UserId => Guid.Parse(_httpContextAccessor.HttpContext?.User?.FindFirstValue(ClaimTypes.NameIdentifier) ?? string.Empty);
public string FullName => _httpContextAccessor.HttpContext?.User?.FindFirstValue("FullName") != null
 ? _httpContextAccessor.HttpContext?.User?.FindFirstValue("FullName")
 : _httpContextAccessor.HttpContext?.User?.FindFirstValue(ClaimTypes.Name);
public string Avatar => _httpContextAccessor.HttpContext?.User?.FindFirstValue("Avatar") != null
 ? _httpContextAccessor.HttpContext?.User?.FindFirstValue("Avatar")
 : "/Themes/img/no_avatar.png";

}

but _httpContextAccessor.HttpContext?.User?.FindFirstValue(ClaimTypes.NameIdentifier) is null always.

Update :

I add this to startup. it is ok.

 app.UseAuthorization();
 app.UseAuthentication();

• Mohammad Aghazadeh: Show exactly where you request them and it is null, also Put the controller and startup.cs or program.cs file code
• Dimitris Maragkos: What does _httpContextAccessor.HttpContext?.User?.Identity.IsAuthenticated return?
• ar.gorgin: @DimitrisMaragkos it is false
• Dimitris Maragkos: Have you added [Authorize] attribute to the Controller you are calling?
• ar.gorgin: Please see the new edition

Answer 1

If you want to access the IHttpContextAccessor in your DbContext class and its overridden SavingChanges method, don't do it! Instead create a SaveChangesInterceptor and then inject your services as usual:

public class AuditableEntitiesInterceptor : SaveChangesInterceptor
{
 private readonly IHttpContextAccessor _httpContextAccessor;
 private readonly ILogger<AuditableEntitiesInterceptor> _logger;
 public AuditableEntitiesInterceptor(
 IHttpContextAccessor httpContextAccessor,
 ILogger<AuditableEntitiesInterceptor> logger)
 {
 _httpContextAccessor = httpContextAccessor ?? throw new ArgumentNullException(nameof(httpContextAccessor));
 _logger = logger ?? throw new ArgumentNullException(nameof(logger));
 }

Then you should register your new interceptor:

services.AddSingleton<AuditableEntitiesInterceptor>();

And finally add it/introduce it to EF-Core this way:

services.AddDbContextPool<ApplicationDbContext>((serviceProvider, optionsBuilder) => 
optionsBuilder.AddInterceptors(serviceProvider.GetRequiredService<AuditableEntitiesInterceptor>());