C#•14mo ago

❔ How to configure an external provider in .Net8 Blazor with individual auth?

Hey guys, I'm having problems adding an external authentication provider to the basic Blazor WebApp template.

        services.AddAuthentication(IdentityConstants.ApplicationScheme).AddBattleNet(options =>
        {
            var bnSection = config.GetSection("Authentication:BattleNet");
            var clientId = bnSection["ClientId"];
            var clientSecret = bnSection["ClientSecret"];

            options.Region = BattleNetAuthenticationRegion.Europe;
            options.ClientId = clientId;
            options.ClientSecret = clientSecret;
            options.Scope.Add("oidc");
        }).AddCookie(IdentityConstants.ExternalScheme).AddApplicationCookie();

        services.AddAuthentication(IdentityConstants.ApplicationScheme).AddBattleNet(options =>
        {
            var bnSection = config.GetSection("Authentication:BattleNet");
            var clientId = bnSection["ClientId"];
            var clientSecret = bnSection["ClientSecret"];

            options.Region = BattleNetAuthenticationRegion.Europe;
            options.ClientId = clientId;
            options.ClientSecret = clientSecret;
            options.Scope.Add("oidc");
        }).AddCookie(IdentityConstants.ExternalScheme).AddApplicationCookie();

When doing it like this the oidc flow works fine, but now navigating to "Account/Manage" gives an "Error: Unable to load user with ID 'BattleNetId'". This seems to happen, because GetUserAsync(principal) in UserAccessor.cs tries to fetch a user with the BattleNetId from AspNetUsers instead of doing a lookup in AspNetUserLogins first. Is the way I registered that external provider even correct, because I don't entirely understand those AddCookie calls, but without that I get a runtime Error. How do I "correctly" fetch the user if he is logged in using an external provider?

34 Replies

JoschiOP•14mo ago

Adding options.SignInScheme = IdentityConstants.ExternalScheme; to the provider config now results in the new user being stored and fetched correctly.

JakenVeina•14mo ago

what Blazor framework is this?

JoschiOP•14mo ago

It's the .Net8 rc2 Blazor WebApp template created in Rider with individual authentication.

JakenVeina•14mo ago

okay what Blazor framework is this?

JoschiOP•14mo ago

Sorry I'm confused, what you want to know specifically. All the code I shared is from the template which uses EFCore and Identity. With a a Nugget for the additional provider. It all runs server side.

JakenVeina•14mo ago

so, Blazor Server?

JoschiOP•14mo ago

Yes, currently I haven't registered the WASM services and don't have anything running as WASM or Auto component.

JakenVeina•14mo ago

do you plan to? that's a weird thing to say if you're actually using Blazor Server

JoschiOP•14mo ago

I may want to try running mostly in auto. But that will prove difficult with database access. And I haven't thought about it that much

JakenVeina•14mo ago

auto?

JoschiOP•14mo ago

The new .NET 8 Auto InteractiveAuto mode that fetches the wasm runtime in the background and switches to wasm on reload

JakenVeina•14mo ago

that sounds horrifying the server-side pre-rendering option, basically anyway so

gives an "Error: Unable to load user with ID 'BattleNetId'"

what gives this error?

JoschiOP•14mo ago

UserAccessor redirects to the Error Page with this explicit string when it can't find the user.

JakenVeina•14mo ago

what is UserAccessor?

JoschiOP•14mo ago

A class in the template that is used to get the user from the db.

JakenVeina•14mo ago

let's see it

JoschiOP•14mo ago

Can't rn don't have my laptop

JakenVeina•14mo ago

mm-kay

JoschiOP•14mo ago

That's the method that's called from there. The rest of the class is just dependency injection

public async Task<User> GetRequiredUserAsync()
    {
        var principal = httpContextAccessor.HttpContext?.User ??
                        throw new InvalidOperationException(
                            $"{nameof(GetRequiredUserAsync)} requires access to an {nameof(HttpContext)}.");

        var user = await userManager.GetUserAsync(principal);

        if (user is null)
        {
            // Throws NavigationException, which is handled by the framework as a redirect.
            redirectManager.RedirectToWithStatus("/Account/InvalidUser",
                $"Error: Unable to load user with ID '{userManager.GetUserId(principal)}'.");
        }

        return user;
    }

public async Task<User> GetRequiredUserAsync()
    {
        var principal = httpContextAccessor.HttpContext?.User ??
                        throw new InvalidOperationException(
                            $"{nameof(GetRequiredUserAsync)} requires access to an {nameof(HttpContext)}.");

        var user = await userManager.GetUserAsync(principal);

        if (user is null)
        {
            // Throws NavigationException, which is handled by the framework as a redirect.
            redirectManager.RedirectToWithStatus("/Account/InvalidUser",
                $"Error: Unable to load user with ID '{userManager.GetUserId(principal)}'.");
        }

        return user;
    }

I just found that in a history I sadly can't share the rest rn.

JakenVeina•14mo ago

sure so, either the user doesn't exist in the database, or principal doesn't contain a user ID (or whatever userManager uses to lookup a user is BattleNetId the ID of a test user you created?

JoschiOP•14mo ago

The priciple contains a claim from the external provider that carries the id of that external provider. The BattleNetid (Sorry seems like that original question wasn't too clear)

JakenVeina•14mo ago

is BattleNetId the ID of a valid user? in the database?

JoschiOP•14mo ago

It does a lookup for this external id on the user table and doesn't find anything. Because the user itself has its own id. What should happen is, that it looks up in AspUserLogins (or however that table is called exactly). There a mapping of external provider+Id to internal userid is stored.

JakenVeina•14mo ago

okay so the principal is likely malformed let's look at it

JoschiOP•14mo ago

I will come back to you with this tomorrow if that's fine. I'm on a trip right now and as I mentioned can't really post or test any code. But thanks for trying to help!

JakenVeina•14mo ago

this is a chat app that's how it works respond when you can

JoschiOP•14mo ago

Still rude to be in a conversation and just stop responding imo .

JakenVeina•14mo ago

meh you already stated you don't have access to your code at the moment

Accord•14mo ago

Was this issue resolved? If so, run /close - otherwise I will mark this as stale and this post will be archived until there is new activity.

JoschiOP•14mo ago

JakenVeina•14mo ago

is one of those blacked-out values "BattleNetId"?

JoschiOP•14mo ago

In the first collapsed claim the nameidentifier is the id. The rest are the name

JakenVeina•14mo ago

but are any of them "BattleNetId"? presumably not so, I guess our assumption was wrong then principal seems to be fine, let's dig into GetUserAsync()

Accord•14mo ago

Was this issue resolved? If so, run /close - otherwise I will mark this as stale and this post will be archived until there is new activity.

Gaming

Programming

❔ How to configure an external provider in .Net8 Blazor with individual auth?