Program.cs

using Microsoft.AspNetCore.Components.Authorization;
using Microsoft.AspNetCore.Identity;
using Microsoft.EntityFrameworkCore;
using SignalRSimpleChat.Components;
using SignalRSimpleChat.Components.Account;
using SignalRSimpleChat.Data;
using SignalRSimpleChat;

var builder = WebApplication.CreateBuilder( args );

// Add services to the container.
builder.Services.AddRazorComponents( )
    .AddInteractiveServerComponents( );

builder.Services.AddCascadingAuthenticationState( );
builder.Services.AddScoped<IdentityUserAccessor>( );
builder.Services.AddScoped<IdentityRedirectManager>( );
builder.Services.AddScoped<AuthenticationStateProvider, IdentityRevalidatingAuthenticationStateProvider>( );

builder.Services.AddAuthentication( options =>
    {
        options.DefaultScheme = IdentityConstants.ApplicationScheme;
        options.DefaultSignInScheme = IdentityConstants.ExternalScheme;
    } )
    .AddIdentityCookies( );

var connectionString = builder.Configuration.GetConnectionString( "DefaultConnection" ) ?? throw new InvalidOperationException( "Connection string 'DefaultConnection' not found." );
builder.Services.AddDbContext<ApplicationDbContext>( options =>
    options.UseSqlite( connectionString ) );
builder.Services.AddDatabaseDeveloperPageExceptionFilter( );

builder.Services.AddIdentityCore<ApplicationUser>( options => options.SignIn.RequireConfirmedAccount = true )
    .AddEntityFrameworkStores<ApplicationDbContext>( )
    .AddSignInManager( )
    .AddDefaultTokenProviders( );

builder.Services.AddSingleton<IEmailSender<ApplicationUser>, IdentityNoOpEmailSender>( );

// Add Chat service
builder.Services.AddScoped<ChatService>( );

var app = builder.Build( );

// Configure the HTTP request pipeline.
if ( app.Environment.IsDevelopment( ) )
{
    app.UseMigrationsEndPoint( );
}
else
{
    app.UseExceptionHandler( "/Error", createScopeForErrors: true );
    // The default HSTS value is 30 days. You may want to change this for production scenarios, see https://aka.ms/aspnetcore-hsts.
    app.UseHsts( );
}

app.UseHttpsRedirection( );

app.UseStaticFiles( );
app.UseAntiforgery( );

app.MapRazorComponents<App>( )
    .AddInteractiveServerRenderMode( );

// Add SignalR hub
app.MapHub<ChatHub>( ChatHub.HubUrl );

// Add additional endpoints required by the Identity /Account Razor components.
app.MapAdditionalIdentityEndpoints( );

app.Run( );