/// <summary>
/// https://duo.com/docs/authapi#/auth
/// </summary>
/// <param name="user_id">Permanent, unique identifier for the user as generated by Duo upon user creation (e.g. DUYHV6TJBC3O4RITS1WC). Exactly one of user_id and username must be specified.</param>
/// <param name="ipaddr">The IP address of the user to be authenticated, in dotted quad format. This will cause an "allow" response to be sent if appropriate for requests from a trusted network.</param>
public async Task <DuoResponse <AuthResult> > AuthAutoByUserIdAsync(string user_id, string ipaddr = null)
{
var request = builder.AuthRequest(user_id, null, "auto", ipaddr, null, "auto", null);
var response = await client.SendAsync(request).ConfigureAwait(false);
return(await DuoResponse.ParseAsync <AuthResultModel, AuthResult>(response));
}
