Custom AuthenticationStateProvider returns "empty user"

in our application I'd like to use the user management of our fat client. For this I have written a custom AuthenticationStateProvider:

public class MyAuthenticationStateProvider : ServerAuthenticationStateProvider, IAuthentorizationService, IDisposable
{
    public MyAuthenticationStateProvider (IPermissionManager permissionManager)
    {
         //User management service of the fat client
        _permissionManager = permissionManager;
    }

    public override Task<AuthenticationState> GetAuthenticationStateAsync()
    {
        if (_permissionManager.PermissionUser == null)
        {
            var emptyUser = new ClaimsPrincipal(new ClaimsIdentity(new Claim[0]));
            return Task.FromResult(new AuthenticationState(emptyUser));
        }
        var identity = new ClaimsIdentity(new[]
        {
            new Claim(ClaimTypes.Name, _permissionManager.PermissionUser.User.GetName())
        }, "FatClientAuthentication");
        var user = new ClaimsPrincipal(identity);
        return Task.FromResult(new AuthenticationState(user));
    }

    public async Task<bool> LoginUser(string userName, string password)
    {
        //Login via WCF connection
        var response = await _clientProxy.Login(new LoginRequest
        {
            LoginUserName = userName,
            Password = password

        });
        response.LogExceptionIfFaulted(_logger);
        if (response.Ok)
        {
            _permissionManager.Initialize(response.LoggedInUser);
            NotifyAuthenticationStateChanged(GetAuthenticationStateAsync());
        }
        return response.Ok;
    }

The login works fine. For testing purposes I always log in with fixed user credentials. After the successful login I fire the NotifyAuthenticationStateChanged event, which results in a correct call of the GetAuthenticationStateAsync method. The now logged in user is correctly wrapped inside the AuthenticationState. When debugging the code I can see that the Identity with the name claim is the correct user and the IsAuthenticated property is true.

However, when using the "AuthorizeView" component, I always get an "empty user" (no name claim, no user name, IsAuthenticated is false)

I now have a small component just for testing:

<AuthorizeView>
<Authorized>
    <h2>User @context.User.Identity.Name</h2> is logged in!
    Claims:
    <ul>
        @foreach (var claim in context.User.Claims)
        {
            <li>[email protected]; [email protected]</li>
        }
    </ul>
    @context.User.Claims
    <p>Current count: @currentCount</p>

    <button class="btn btn-primary" @onclick="IncrementCount">Click me</button>
</Authorized>
<NotAuthorized>
    <h2>User @context.User.Identity.Name</h2> @*this is an empty string*@
    <h2>Authentication Type: @context.User.Identity.AuthenticationType</h2> @*empty*@
    <h2>Authenticated: @context.User.Identity.IsAuthenticated</h2>@*false*@
    No user is logged in!
</NotAuthorized>

Im using the AuthorizeRouteView and the CascadingAuthenticationState in the App.razor like in the official sample displayed in https://learn.microsoft.com/en-us/aspnet/core/security/blazor/?view=aspnetcore-3.1

Accessing the AuthenticationState via an CascadingParameter also results in the same "empty user".

Appreciate any help,

tilt32

EDIT 1

So I looked into the login behaviour again, making sure that the event is called. I then figured out, that my AuthenticationStateChanged event has no subscribers (is null). My impression was, that something in the framework attaches to this event at startup. Maybe I did forget some configuration method call in the startup ? This is what I do in the configure services:

    services.AddScoped<AuthenticationStateProvider, MyAuthenticationStateProvider>();
            services.AddScoped<ServerAuthenticationStateProvider, MyAuthenticationStateProvider>();
//Interface which I use in my LoginCompontent and at Startup to log in with the default user or some real user credentials
            services.AddScoped<IAuthenticationService, MyAuthenticationStateProvider>();

I also tried the approach suggested by user enet. Sadly with no success, the result was the same. During the login a call to NotifyAuthenticationStateChanged and hence to the event with no subscribers is done.

The WCF service we use in the background requires a logged in user. Hence i made a guest user with limited rights to solve this issue. So the app steps into the GetAuthenticationStateAsync and tries to fire the AuthenticationStateEvent directly after startup (during a loading screen).

EDIT 2

So I now tried some additional setup steps, from which Microsoft wrote in the Blazor documentation, that they should not be necessary for server-side blazor:

The ConfigureServices now looks like this

//Authentication & Authorization setup
services.AddOptions();
services.AddAuthenticationCore();
services.AddAuthorizationCore();
services.AddScoped<IPermissionManager, SingleUserPermissionManager>();
services.AddScoped<AuthenticationStateProvider, MyAuthenticationStateProvider>();
services.AddScoped<ServerAuthenticationStateProvider, MyAuthenticationStateProvider>();
services.AddScoped<IAuthenticationService, MyAuthenticationStateProvider>();

In the Configure(IApplicationBuilder app, IWebHostEnvironment env) Method, I added the following calls:

app.UseAuthentication();
app.UseAuthorization();

This did also have no effect.