ASP.NET Core 8 Web API endpoint does not contain my custom fields

Question

I created an entity ApplicationUser and successfully extended it to IdentityUser and migrations created it in the database.

But when I go to the register endpoint, it does not show my custom fields to be registered:

Entity ApplicationUser:

public class ApplicationUser : IdentityUser
{
    public string? FirstName { get; set; }
    public string? LastName { get; set; }
    public int FavoriteTeam { get; set; }
    public string? PhotoPath { get; set; }
    public string? FirstLast { get; set; }
}

DbContext:

public class ContextBase : IdentityDbContext<ApplicationUser>
{
    public ContextBase(DbContextOptions<ContextBase> options) : base(options)
    {
    }
}

Program

builder.Services.AddIdentityApiEndpoints<ApplicationUser>()
    .AddEntityFrameworkStores<ContextBase>();
     
-----

app.MapIdentityApi<ApplicationUser>();

Answer 1

There can be possible reason if the API endpoint that handles registration is not configured to accept the additional fields of your ApplicationUser. could you try this below code:

public class RegisterDto
{
    public string Email { get; set; }
    public string Password { get; set; }

    // Custom fields
    public string FirstName { get; set; }
    public string LastName { get; set; }
    public int FavoriteTeam { get; set; }
    public string PhotoPath { get; set; }
}

Update the registration endpoint

public async Task<IActionResult> Register(RegisterDto model)
{
    var user = new ApplicationUser
    {
        UserName = model.Email,
        Email = model.Email,
        FirstName = model.FirstName,
        LastName = model.LastName,
        FavoriteTeam = model.FavoriteTeam,
        PhotoPath = model.PhotoPath
    };

    // other registration process
}

Answer 2

Here is one way to write a custom identity register endpoint. This endpoint takes a RegisterDTO and maps it to a User object.

[HttpPost("CustomRegister")]
public async Task<Results<Ok, ValidationProblem>> PostNew (RegisterDTO registration,  [FromServices] IServiceProvider sp) {

    var userManager = sp.GetRequiredService<UserManager<User>>();

    if (!userManager.SupportsUserEmail)
    {
        throw new NotSupportedException($"User store with email support required.");
    }

    var userStore = sp.GetRequiredService<IUserStore<User>>();
    var emailStore = (IUserEmailStore<User>)userStore;
    var email = registration.Email;

       if (string.IsNullOrEmpty(email) || !_emailAddressAttribute.IsValid(email))
          {
                    return CreateValidationProblem(IdentityResult.Failed(userManager.ErrorDescriber.InvalidEmail(email)));
          }

     var user = new User();
     user.Contact = new Contact
         {
                    FirstName = registration.Firstname,
                    MiddleName = registration.Middlename,
                    LastName = registration.Lastname,
                    PhoneNumbers = new List<PhoneNumber> { new PhoneNumber
                {
                    Number = registration.Phonenumber
                } },
                    Selfie= registration.Profilephoto,
                    IDImage = registration.Idimage

            };

     await userStore.SetUserNameAsync(user, registration.Username, CancellationToken.None);
     await emailStore.SetEmailAsync(user, email, CancellationToken.None);
     var result = await userManager.CreateAsync(user, registration.Password);

       if (!result.Succeeded)
            {
                return CreateValidationProblem(result);
            }

 //   await SendConfirmationEmailAsync(user, userManager, context, email);
      return TypedResults.Ok();
    }

I wrote this using code from microsoft identityApiEndpointRouteBuilderExtensions so it should be work flawlessly with other identity features. You can find the actual code on https://github.com/dotnet/aspnetcore/blob/main/src/Identity/Core/src/IdentityApiEndpointRouteBuilderExtensions.cs.