How to persist extended Identity(Authentication) fields. net CORE 5.0

Question

I have a project in ASP.NET MVC CORE 5.0 .

What I want to do:

• Retrieve the information dadAleatorio user logged in, in any controller to insert them in wheres and creates.
• For example I want to register an item, and in it I put this dadAleatorio (logged user information)

With stretched fields I mean:

• The Identity by default comes the predefined fields, but searching deep, I saw that it is possible to add more information to the logged in user

I created a basic authentication template using Identity:

public class AccountController : Controller
{
    private readonly UserManager<ApplicationUser> _userManager;
    private readonly SignInManager<ApplicationUser> _signInManager;


    public AccountController(UserManager<ApplicationUser> userManager,
                                SignInManager<ApplicationUser> signInManager)
    {
        _userManager = userManager;
        _signInManager = signInManager;
    }

    [HttpGet]
    public IActionResult Login(string returnUrl)
    {
        return View(new ViewModels.LoginViewModel()
        {
            ReturnUrl = returnUrl
        });
    }

    [HttpPost]
    public async Task<ActionResult> Login(ViewModels.LoginViewModel loginVM)
    {
        if (!ModelState.IsValid)
        {
            return View(loginVM);
        }

        var user = await _userManager.FindByNameAsync(loginVM.UserName);

        if (user != null)
        {
            var result = await _signInManager.PasswordSignInAsync(user, loginVM.Password, false, false);

            if (result.Succeeded)
            {
                //Verifica se a url é nula, e se ela é interna para evitar open redirect atacks
                if (!string.IsNullOrEmpty(loginVM.ReturnUrl) && Url.IsLocalUrl(loginVM.ReturnUrl))
                {
                    return LocalRedirect(loginVM.ReturnUrl);

                }
                
                return RedirectToAction("Index", "Home");
            }
        }
        ModelState.AddModelError("", "Usuário/Senha inválidos");
        return View(loginVM);
    }

    public IActionResult Register()
    {
        return View();
    }

    [HttpPost]
    [ValidateAntiForgeryToken]
    public async Task<IActionResult> Register(ViewModels.LoginViewModel registroVM)
    {
        if (ModelState.IsValid)
        {
            var user = new ApplicationUser() { UserName = registroVM.UserName };
            var result = await _userManager.CreateAsync(user, registroVM.Password);

            if (result.Succeeded)
            {
                return RedirectToAction("Index", "Home");
            }

            foreach (var error in result.Errors)
            {
                ModelState.AddModelError("", error.Description);
            }
        }
        return View(registroVM);
    }

    [HttpPost]
    public async Task<IActionResult> Logout()
    {
        await _signInManager.SignOutAsync();
        return RedirectToAction("Index", "Home");
    }
    [HttpGet]
    [AllowAnonymous]
    public IActionResult AccessDenied()
    {
        return View();
    }
}

I needed to add an extra column to the dbo.AspNetUsers. I inserted it via SQL because I am working with database first.

I also created a class to accomplish this:

    public class ApplicationUser : IdentityUser
{
    [PersonalData]
    public int? dadoaleatorio { get; set; }

}

When injecting Identity anywhere in the project I use that Applicationuser and everything works smoothly. But at certain points of the project I need to use this "dataAleatorio" field to pass as a parameter when creating certain objects, or show certain tables. How to proceed?

Edit:

I was able to recover user data on any controller using:

var user = await _userManager.GetUserAsync(HttpContext.User);

How do I persist with this data?

• Currently at each Reload or controller change there would be a query in the database
• I know that the default Identity data is saved in cookies. It’s like make an extension of that too?

Answer 1

To be able to persist the data customized (additional fields of the aspNetUser table) and use them anywhere in the code I did the following:

First I created a class that adds CLAIMS.

public class IdentityExtensions : UserClaimsPrincipalFactory<ApplicationUser>
{
    public IdentityExtensions(
        UserManager<ApplicationUser> userManager,
        IOptions<IdentityOptions> optionsAccessor)
            : base(userManager, optionsAccessor)
    {
    }

    protected override async Task<ClaimsIdentity> GenerateClaimsAsync(ApplicationUser user)
    {
        var identity = await base.GenerateClaimsAsync(user);
        identity.AddClaim(new Claim(type: "dadoAleatorio", value: user.dadoAleatorio.ToString()));

}

Once this is done, just go to Startup.Cs and add the class in configureServices:

services.AddIdentity<ApplicationUser, IdentityRole>()
         .AddEntityFrameworkStores<ApplicationContext>()
         .AddDefaultTokenProviders()
         .AddClaimsPrincipalFactory<IdentityExtensions>(); //ADICIONE ESSA LINHA

And finally just request this CLAIM where necessary

var LoggedUserDadoAleatorio = User.FindFirst("dadoAleatorio").Value;