public ActionResult <IEnumerable <Greeting> > Get()
        {
            IEnumerable <Greeting> greetingList = _greetingService.GetAll();

            if (greetingList != null && greetingList.Count() > 0)
            {
                return(Ok(greetingList));
            }
            else
            {
                return(NoContent());
            }
        }