private IQueryable <League> FilterLeagues(IQueryable <League> query, LeagueFilter filter)
        {
            if (filter != null)
            {
                query = filter.FilterLeagues(query);
            }

            return(query);
        }
 public async Task <IEnumerable <League> > GetAllWithFilter(LeagueFilter filter)
 {
     return(await this.FilterLeagues(this.db.Leagues, filter)
            .OrderBy(l => l.Name)
            .ToListAsync());
 }