public class ExceptionToJsonMiddleware
    {
        private readonly RequestDelegate _next;
        private ILogger<ExceptionToJsonMiddleware> _logger;

        public ExceptionToJsonMiddleware(RequestDelegate next)
        {
            this._next = next;
        }

        public async Task Invoke(HttpContext context, ILoggerFactory loggerFactory)
        {
            try
            {
                await _next(context);
            }
            catch (Exception ex)
            {
                _logger = loggerFactory.CreateLogger<ExceptionToJsonMiddleware>();

                _logger.LogError(JsonConvert.SerializeObject(new ExceptionProfilerModel
                {
                    Path = context.Request.Path.HasValue ? context.Request.Path.Value : string.Empty,
                    Request = request,
                    ExceptionMessage = ex.Message,
                    StackTrace = ex.StackTrace,
                    RequestTime = DateTimeOffset.Now
                }, Formatting.Indented));


                await HandleExceptionAsync(context, ex);
            }
        }



        private Task HandleExceptionAsync(HttpContext context, Exception exception)
        {
            var code = HttpStatusCode.InternalServerError; // 500 if unexpected
            switch (exception)
            {
                case FriendlyException ex:
                    code = HttpStatusCode.BadRequest;
                    break;
                case AccessDeniedException ex:
                    code = HttpStatusCode.Forbidden;
                    break;
                case EntityNotFoundException ex:
                    code = HttpStatusCode.NotFound;
                    break;
            }


            var result = JsonConvert.SerializeObject(new {error = exception.Message});
            context.Response.ContentType = "application/json";
            context.Response.StatusCode = (int) code;
            return context.Response.WriteAsync(result);
        }
    }