temp.cs

var appOptions = _conf.GetSection("AppOptions");
var purposes = appOptions.GetSection("CookieAadPurposes")
    .GetChildren();

services.AddCors(options =>
{
    options.AddPolicy(CorsPolicyName,
        //.AllowCredentials()
        builder => builder.AllowAnyHeader()
            .AllowAnyMethod()
            .AllowAnyOrigin()
            .Build()
    );
});

services.AddAuthentication(IdentityServerAuthenticationDefaults.AuthenticationScheme)
    .AddIdentityServerAuthentication();

services.AddDataProtection()
    .PersistKeysToFileSystem(new DirectoryInfo(@$"{appOptions["CookieKeyPath"]}"))
    .SetApplicationName($"{purposes.FirstOrDefault()}")
    .UseCryptographicAlgorithms(new AuthenticatedEncryptorConfiguration()
    {
        EncryptionAlgorithm = EncryptionAlgorithm.AES_256_CBC,
        ValidationAlgorithm = ValidationAlgorithm.HMACSHA256
    });

services.AddControllers()
    .AddNewtonsoftJson(options =>
    {
        options.SerializerSettings
            .ReferenceLoopHandling = ReferenceLoopHandling.Ignore;
        options.SerializerSettings
            .PreserveReferencesHandling = PreserveReferencesHandling.Objects;
    });

services.AddInfrastructure();

services.AddSingleton<ICookieDataProtector, CookieDataProtector>();
services.AddSingleton<IHelper, Helper>();

services.Configure<AppOptions>(options =>
{
    appOptions.Bind(options);
});
services.Configure<ForwardedHeadersOptions>(options => {
    options.ForwardedHeaders =
        ForwardedHeaders.XForwardedFor | ForwardedHeaders.XForwardedProto;
    options.KnownNetworks
        .Clear();
    options.KnownProxies
        .Clear();
    options.RequireHeaderSymmetry = false;
});

services.ConfigureOptions<CustomIdentityServerOptions>();