public async Task <ActionResult <Attribute> > PostAttribute(Attribute attribute)
        {
            _context.Attributes.Add(attribute);
            await _context.SaveChangesAsync();

            return(CreatedAtAction("GetAttribute", new { id = attribute.AttributeId }, attribute));
        }
        public async Task <IActionResult> PutAttribute(int id, Attribute attribute)
        {
            if (id != attribute.AttributeId)
            {
                return(StatusCode(StatusCodes.Status500InternalServerError, new Response {
                    Status = "Error", Message = "This attribute id does not exist!"
                }));
            }

            _context.Entry(attribute).State = EntityState.Modified;

            try
            {
                await _context.SaveChangesAsync();
            }
            catch (DbUpdateConcurrencyException)
            {
                if (!AttributeExists(id))
                {
                    return(StatusCode(StatusCodes.Status500InternalServerError, new Response {
                        Status = "Error", Message = "This attribute id does not exist!"
                    }));
                }
                else
                {
                    throw;
                }
            }

            return(NoContent());
        }