ServiceStack Credentials AuthProvider return custom exception

Question

Using ServiceStack 8.~ with .NET 6.

We've implemented a custom credentials AuthProvider. When authentication fails, we would like to throw our own error message, not just invalid username/password; we have several conditions (user active, locked out etc.) we'd like to tell the user about.

Our authentication logic resides in the method

public override bool TryAuthenticate(IServiceBase authService, string userName, string password)

This method returns a bool, so none of our custom errors are returned. If we return false, ServiceStack returns "invalid user".

Where and how can we implement our custom checks and add a more specific error?

public override bool TryAuthenticate(IServiceBase authService, string userName, string password)
{
    try
    {
        ServiceInterface.UsersCredentialsService usersCredentialsService = new ServiceInterface.UsersCredentialsService();

        // this method will throw the error
        _user = usersCredentialsService.Authenticate(new ServiceModel.Authenticate
                {
                    User = userName,
                    Password = password
                });

        return true;
    }
    catch (Exception ex)
    {
        Log.Error(ex);
        Log.Error(ex.Message);
        return false;
    }
}

Answer 1

You would also need to override the Authenticate() method where you can catch any exceptions, inspect the session and throw your own custom exception, e.g:

public override object Authenticate(
    IServiceBase authService, IAuthSession session, Authenticate request)
{
    try
    {
        return base.Authenticate(authService,session,request);
    }
    catch (Exception e)
    {
        // throw custom Exception
        throw HttpError.Unauthorized(customMessage);
    }
}