public IActionResult GetSupermarketCollection([ModelBinder(BinderType = typeof(ArrayModelBinder))] IEnumerable <int> ids)
        {
            // check ids were passed in
            if (ids == null)
            {
                return(BadRequest());
            }

            // get all supermarkets with matching ID's
            var supermarketEntities = _supermarketRepository.GetSupermarketsByIds(ids);

            // check there is a supermarket for each id passed in
            if (ids.Count() != supermarketEntities.Count())
            {
                return(NotFound());
            }

            // map and return data
            var supermarketsToReturn = Mapper.Map <IEnumerable <SupermarketDTO> >(supermarketEntities);

            return(Ok(supermarketsToReturn));
        }