marechai/Marechai/Areas/Identity/Pages/Account/Manage/Disable2fa.cshtml.cs

using System;
using System.Threading.Tasks;
using Marechai.Database.Models;
using Microsoft.AspNetCore.Identity;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.RazorPages;
using Microsoft.Extensions.Logging;

namespace Marechai.Areas.Identity.Pages.Account.Manage
{
    public class Disable2faModel : PageModel
    {
        readonly ILogger<Disable2faModel>     _logger;
        readonly UserManager<ApplicationUser> _userManager;

        public Disable2faModel(UserManager<ApplicationUser> userManager, ILogger<Disable2faModel> logger)
        {
            _userManager = userManager;
            _logger      = logger;
        }

        [TempData]
        public string StatusMessage { get; set; }

        public async Task<IActionResult> OnGet()
        {
            ApplicationUser user = await _userManager.GetUserAsync(User);

            if(user == null)
            {
                return NotFound($"Unable to load user with ID '{_userManager.GetUserId(User)}'.");
            }

            if(!await _userManager.GetTwoFactorEnabledAsync(user))
            {
                throw new
                    InvalidOperationException($"Cannot disable 2FA for user with ID '{_userManager.GetUserId(User)}' as it's not currently enabled.");
            }

            return Page();
        }

        public async Task<IActionResult> OnPostAsync()
        {
            ApplicationUser user = await _userManager.GetUserAsync(User);

            if(user == null)
            {
                return NotFound($"Unable to load user with ID '{_userManager.GetUserId(User)}'.");
            }

            IdentityResult disable2faResult = await _userManager.SetTwoFactorEnabledAsync(user, false);

            if(!disable2faResult.Succeeded)
            {
                throw new
                    InvalidOperationException($"Unexpected error occurred disabling 2FA for user with ID '{_userManager.GetUserId(User)}'.");
            }

            _logger.LogInformation("User with ID '{UserId}' has disabled 2fa.", _userManager.GetUserId(User));
            StatusMessage = "2fa has been disabled. You can reenable 2fa when you setup an authenticator app";

            return RedirectToPage("./TwoFactorAuthentication");
        }
    }
}