public async Task <IActionResult> Add([FromBody] CreatePathModel model)
        {
            try
            {
                await paths.AddAsync(model.FromCityId, model.ToCityId, model.SelectedPathLength);

                return(this.Ok());
            }
            catch (Exception e)
            {
                return(this.ValidationProblem(detail: e.Message));
            }
        }