public ActionResult <IEnumerable <string> > PutCalendar(long calendarId, CalendarPost calendarPost)
        {
            if (model.GetCalendar(calendarId) == null)
            {
                return(NotFound());
            }

            if (!auth.CheckIfCalendarPermissions(calendarPost, calendarId))
            {
                return(Unauthorized());
            }

            if (model.PutCalendar(calendarPost, calendarId))
            {
                return(NoContent());
            }
            else
            {
                return(Conflict());
            }
        }