public async Task<bool> CheckRepresentationExistsAsync(
            Controller controller,
            string representationId)
        {
            if (controller == null)
            {
                throw new ArgumentNullException(nameof(controller));
            }

            if (string.IsNullOrWhiteSpace(representationId))
            {
                throw new ArgumentNullException(nameof(representationId));
            }

            var concatenatedEtags = controller.GetIfMatch();
            var unmodifiedSince = controller.GetUnmodifiedSince();
            var checkDateCallback = new Func<DateTime, ConcurrentObject, bool>((d, c) =>
            {
                return c.DateTime <= d;
            });
            var checkEtagCorrectCallback = new Func<ConcurrentObject, List<EntityTagHeaderValue>, bool>((c, etags) =>
            {
                return etags.Any(e =>
                {
                    if (e.IsWeak)
                    {
                        // Weak etag
                        if (c.Etag.Contains(e.Tag))
                        {
                            return true;
                        }
                    }
                    else
                    {
                        if (e.Tag == c.Etag)
                        {
                            return true;
                        }
                    }

                    return false;
                });
            });
            return await ContinueExecution(concatenatedEtags, unmodifiedSince, representationId, checkDateCallback, checkEtagCorrectCallback);
        }