public IActionResult Add([FromBody] Purchase request)
        {
            var identity = User.Identity as ClaimsIdentity;
            var userId = (from c in identity.Claims
                where c.Type == "Id"
                select c.Value).First();
            var user = _userRepository.GetById(userId);
            request.Author = new RequestUser()
            {
                Id = user.Id,
                Name = user.Name,
                LastName = user.LastName,
                SecondName = user.SecondName,
                Position = user.Position
            };
            request.Products = new List<PurchaseProduct>();
            request.Status = new RequestStatus() {Id = "draft", Title = "Черновик"};
            var task = _requestRepository.Add(request);
            return new JsonResult(new {id = task.Result});
        }

_requestRepository.User = User.Identity

[HttpPost("{id:int}/approval")]
        public IActionResult AddApproval(int id)
        {
            _requestRepository.User = User.Identity as ClaimsIdentity;
            var task = _requestRepository.AddApproval(id);
            return new ObjectResult(new {id = task.Result});
        }