Simple MVC Security in ASP.NET | Blog Security pt. 2: Permission and Display

Part 2 in a series on security for an MVC blog site. See Part 1 here

Step 3: Let yourself back in.

So your application is now so secure that even you can't get in.
Lets make a dataservice with a method that will call 2 other functions:

public class DataService
    {
        /* Any injected services go here!!
           Don't forget the constructor!! */

        public async Task ManageDataAsync()
        {
            //Task 1: Seed roles (create and enter into Authorization system
            await SeedRolesAsync();
            // Task 2 seed a few users into AspNetUsers
            await SeedUsersAsync();
        }

I used a dataservice to seed roles when there are none. (this is the first method in that service)

public async Task SeedRolesAsync()
        {
            //Are there roles in the system? 
            if (_context.Roles.Any())
            {
                return;
            }
            //Spin through enum and do stuff
            foreach (var role in Enum.GetNames(typeof(BlogRole)))
            {
                //create Role in system for each role
                await _roleManager.CreateAsync(new IdentityRole(role));
            }
        }

BlogRole is an enum with Administrator and Moderator are the options, so now we have 2 roles that exist in our database.

Lets then seed an adminUser

private async Task SeedUsersAsync()
        {
            if (_context.Users.Any())
            {
                return;
            }
            var adminUser = new BlogUser()
            {
                Email = "[e-mail]",
                UserName = "[e-mail]",
                FirstName = "Admin",
                LastName = "Istrator"
                //OTHER DATA FOR USER CLASS
            };
            await _userManager.CreateAsync(adminUser, _configuration["AdminPassword"]);
            await _userManager.AddToRoleAsync(adminUser, BlogRole.Administrator.ToString());


        }

Where my Admin Password is in my appSettings.json, to keep it private from github. You may also use IdentityUser where I used BlogUser to initialize a user.

The ManageDataAsync is called in your program.cs file
Where the contents of main look like:

        public static async Task Main(string[] args)
        {
            //CreateHostBuilder(args).Build().Run();
            var host = CreateHostBuilder(args).Build();
            var dataService = host.Services.CreateScope().ServiceProvider.GetRequiredService<DataService>();
            await dataService.ManageDataAsync();

            host.Run();
        }

Step 4: Hiding things from the unregistered masses

If a new unregistered user comes to my site, I don't want them to click on something that takes them to a page where access is denied. In my view, I'll add a simple if statement

@if (User.IsInRole("Administrator"))
                    {

                        <li class="nav-item">
                            <a class="nav-link" asp-area="" asp-controller="Blogs" asp-action="Index">Blogs</a>
                        </li>
                        <li class="nav-item">
                            <a class="nav-link" asp-area="" asp-controller="Posts" asp-action="Index">Posts</a>
                        </li>
                    }

The inner content will be whatever you want to display to users in the administrator role. Adding an || to your if can allow for multiple roles, and else statements can be used to display different data for different roles.

An interesting idea is to give the user a gray button that redirects to a purchase page if they aren't a premium user, showing them what they're missing and giving them an option to upgrade.