How to use Roles in ASP.NET Core 2.1?

Question

I've created a test project using:

dotnet new razor --auth Individual --output Test

This creates a Startup.cs that contains:

public void ConfigureServices(IServiceCollection services)
{
    services.Configure<CookiePolicyOptions>(options =>
    {
        // This lambda determines whether user consent for non-essential cookies is needed for a given request.
        options.CheckConsentNeeded = context => true;
        options.MinimumSameSitePolicy = SameSiteMode.None;
    });

    services.AddDbContext<ApplicationDbContext>(options =>
        options.UseSqlite(
            Configuration.GetConnectionString("DefaultConnection")));

    services.AddDefaultIdentity<IdentityUser>()
        .AddEntityFrameworkStores<ApplicationDbContext>();

    services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_1);
}

I want to seed some users and roles. Both users and roles will use the same store (SQLite). I'm using a static class for seeding which it's called from Program.

I can seed users, but not roles, since the above does not seem to inject a RoleManager.

In ASP.NET Core 2.0 the following is used:

services.AddIdentity<IdentityUser, IdentityRole>()

I'm guessing AddDefaultIdentity is new in 2.1 but the problem is that it does not inject a RoleMnager, so what should I do?

Answer 1

It seems that finally Microsoft understood that not every application needs roles and separated them.

Notice that AddDefaultIdentity is declared as:

public static IdentityBuilder AddDefaultIdentity<TUser>(this IServiceCollection services) where TUser : class;

So, you can continue to configure Identity options through that IdentityBuilder. What you want to do is:

services.AddDefaultIdentity<IdentityUser>().AddRoles<IdentityRole>();

Fortunately, they also removed the IUser and IRole constrains, so now you can use models in a completely separate assembly without having to install hundreds of NuGet packages.

Answer 2

Might help someone else: If you add asp.net identity through scaffolding to an existing project, you'll need to edit the IdentityHostingStartup.cs and change the services there instead of in your startup class:

services.AddIdentity<AppUser, IdentityRole>()
                .AddDefaultUI()
                .AddRoles<IdentityRole>()
                .AddRoleManager<RoleManager<IdentityRole>>()
                .AddDefaultTokenProviders()
                .AddEntityFrameworkStores<authContext>();

And then you can use the role manager in your seeding.