Blazor WebAssembly - 页面刷新时未调用 GetAuthenticationStateAsync()

Question

I have custom AuthenticationStateProvider in my Blazor WebAssembly app and it's not calling GetAuthenticationStateAsync method on page refresh so if user is logged in and then they manually refresh page ClaimsPrincipal is AuthenticationState is not populated so user can't be Authorized. I'm using JWT which is saved in cookie for auth, and that cookie remains after page refresh, app just doesn't call GetAuthenticationStateAsync (which it should on page refresh if I learned blazor correctly).

Here's my custom AuthenticationStateProvider:

public class CustomAuthenticationStateProvider : AuthenticationStateProvider
{
    private readonly HttpClient _httpClient;
    public CustomAuthenticationStateProvider(
        IHttpClientFactory httpClientFactory)
    {
        _httpClient = httpClientFactory.CreateClient("APIClient");
    }

    public override async Task<AuthenticationState> GetAuthenticationStateAsync()
    {

        //TODO get token from cookie
        var savedToken = "";

        if (string.IsNullOrWhiteSpace(savedToken))
        {
            return new AuthenticationState(new ClaimsPrincipal(new ClaimsIdentity()));
        }

        return new AuthenticationState(new ClaimsPrincipal(new ClaimsIdentity(ParseClaimsFromJwt(savedToken), "jwt")));
    }

    public void MarkUserAsAuthenticated(string email)
    {
        var authenticatedUser = new ClaimsPrincipal(new ClaimsIdentity(new[] { new Claim(ClaimTypes.Name, email) }, "apiauth"));
        var authState = Task.FromResult(new AuthenticationState(authenticatedUser));
        NotifyAuthenticationStateChanged(authState);
    }

    public void MarkUserAsLoggedOut()
    {
        var anonymousUser = new ClaimsPrincipal(new ClaimsIdentity());
        var authState = Task.FromResult(new AuthenticationState(anonymousUser));
        NotifyAuthenticationStateChanged(authState);
    }
}

EDIT: It was calling GetAuthenticationStateAsync method the entire time, it was just confusing because I was in debugger and it never hit my breakpoint inside of that method, which is problem I saw other people (still not sure why is that).

Answer 1

It depends on where you call GetAuthenticationStateAsync .
ie in BlazorHero project this call is present in the MainLayout.razor :

</NotAuthorized>
    <Authorized>
        @(LoadDataAsync())
        <MudLayout RightToLeft="@_rightToLeft">

in MainLayout.razor.cs :

private async Task LoadDataAsync()
    {
        var state = await _stateProvider.GetAuthenticationStateAsync();
        var user = state.User;
        if (user == null) return;

so I think you need to check where it is called.

The MainLayout is rendered every time you load a page.

A better solution (cleaner) is to add this code in the AfterRender like:

protected override async Task OnAfterRenderAsync(bool firstRender)
{
    if (firstRender)
    {
        await LoadDataAsync();
    }
}