public DataSourceResult GetRateList([ModelBinder(typeof(WebApiDataSourceRequestModelBinder))]DataSourceRequest request, short code, string curr)
 {
    curr = curr ?? "";
    using (var ctx = new ModelerContext())
    {
       IEnumerable<ListRateVM> rates = ctx.getRateList(code, curr);
       return rates.ToDataSourceResult(request);
    }
 }