dotnet new -i Piranha.Templates

dotnet new piranha.razor -o custom-identity

<div class="container mt-5 col-lg-6 col-md-9">

    <form method="post">

        <div class="form-group">
            <label class="col-form-label">Username</label>
            <input class="form-control" type="text" asp-for="Username" autofocus />
        </div>

        <div class="form-group">
            <label class="col-form-label">Password</label>
            <input class="form-control" type="password" asp-for="Password" />
        </div>

        <div>
            <button class="btn btn-primary">Login</button>
        </div>
    </form>
</div>

    // Login.cshtml.cs

    [BindProperties]
    public class LoginModel : PageModel
    {
        public string Username { get; set; }
        public string Password { get; set; }
        public void OnGet()
        {
        }
    }

// Startup.cs - ConfigureServices
 services
    .AddAuthentication(CookieAuthenticationDefaults.AuthenticationScheme)
    .AddCookie(CookieAuthenticationDefaults.AuthenticationScheme,
        options =>
        {
            options.LoginPath = new PathString("/Login");
        });

    // SecurityService.cs
    public class SecurityService : ISecurity
    {
        public async Task<bool> SignIn(object context, string username, string password)
        {
            if (username == "demo" && password == "demo")
            {
                var claims = new List<Claim>();
                claims.Add(new Claim(ClaimTypes.Name, username));

                var identity = new ClaimsIdentity(claims, "demo");
                var principal = new ClaimsPrincipal(identity);

                await ((HttpContext) context).SignInAsync(
                    CookieAuthenticationDefaults.AuthenticationScheme,
                    principal);

                return true;
            }

            return false;
        }

        public async Task SignOut(object context)
        {
            await((HttpContext)context).SignOutAsync(
                CookieAuthenticationDefaults.AuthenticationScheme);
        }
    }

    // Login.cshtml.cs
    private readonly ISecurity security;
    public LoginModel(ISecurity security)
    {
        this.security = security;
    }

    // Startup.cs - ConfigureServices
    services.AddScoped<ISecurity, SecurityService>();

claims.Add(new Claim("PiranhaAdmin", "PiranhaAdmin"));
claims.Add(new Claim("PiranhaAliases", "PiranhaAliases"));