/// <exception cref="InvalidModelException"/>
        /// <exception cref="NotFoundException"/>
        public async Task <Guid> AddAsync(Dtos.Specialty dto)
        {
            var validator           = new Dtos.SpecialtyValidator();
            ValidationResult result = validator.Validate(dto);

            if (!result.IsValid)
            {
                string errMess = string.Empty;

                foreach (var failure in result.Errors)
                {
                    errMess += $"Property { failure.PropertyName } failed validation. Error was: { failure.ErrorMessage }\n";
                }

                throw new InvalidModelException(errMess);
            }

            var id  = Guid.NewGuid();
            var now = DateTime.UtcNow;

            var specialty = new Entities.Specialty
            {
                Id         = id,
                CreatedAt  = now,
                UpdatedAt  = now,
                Name       = dto.Name,
                Code       = dto.Code,
                Discipline = dto.Discipline,
                GroupsCode = dto.GroupsCode
            };

            await _context.AddAsync(specialty);

            await _context.SaveChangesAsync();

            return(id);
        }
        /// <exception cref="InvalidModelException"/>
        /// <exception cref="NotFoundException"/>
        public async Task UpdateAsync(Dtos.Specialty dto)
        {
            if (dto.Id.Equals(Guid.Empty))
            {
                throw new InvalidModelException("Property Id failed validation. Error was: Id is empty");
            }

            var validator           = new Dtos.SpecialtyValidator();
            ValidationResult result = validator.Validate(dto);

            if (!result.IsValid)
            {
                string errMess = string.Empty;

                foreach (var failure in result.Errors)
                {
                    errMess += $"Property { failure.PropertyName } failed validation. Error was: { failure.ErrorMessage }\n";
                }

                throw new InvalidModelException(errMess);
            }

            var specialty = await _context.FindAsync <Entities.Specialty>(dto.Id);

            if (specialty == null)
            {
                throw new NotFoundException($"Entity with id: {dto.Id} not found.");
            }

            specialty.UpdatedAt  = DateTime.UtcNow;
            specialty.Name       = dto.Name;
            specialty.Code       = dto.Code;
            specialty.Discipline = dto.Discipline;
            specialty.GroupsCode = dto.GroupsCode;

            await _context.SaveChangesAsync();
        }