public async Task <IActionResult> PutRegistration(int id, PublicApi.v1.DTO.Registration registration)
        {
            if (id != registration.Id)
            {
                return(BadRequest());
            }

            _bll.Registration.Update(PublicApi.v1.Mappers.RegistrationMapper.MapFromExternal(registration));
            await _bll.SaveChangesAsync();

            return(NoContent());
        }
        public async Task <ActionResult <PublicApi.v1.DTO.Registration> > PostRegistration(PublicApi.v1.DTO.Registration registration)
        {
            await _bll.Registration.AddAsync(PublicApi.v1.Mappers.RegistrationMapper.MapFromExternal(registration));

            await _bll.SaveChangesAsync();

            return(CreatedAtAction("GetRegistration", new { id = registration.Id }, registration));
        }