public async Task Execute(HttpContext httpContext, string genericContentName, string id)
        {
            if (httpContext == null)
            {
                throw new ArgumentNullException(nameof(httpContext));
            }

            if (!ContentTypes.IsValid(genericContentName))
            {
                _Logger.LogError($"Invalid generic content type - {id}.");
                httpContext.Response.StatusCode    = 400;
                httpContext.Response.ContentLength = 0;
            }

            if (!_PublishingId.Validate(id))
            {
                _Logger.LogError($"Invalid content id - {id}.");
                httpContext.Response.StatusCode    = 400;
                httpContext.Response.ContentLength = 0;
            }

            //This looked like a bug?
            if (!httpContext.Request.Headers.TryGetValue("if-none-match", out var etagValue))
            {
                _Logger.LogError($"Required request header missing - if-none-match.");
                httpContext.Response.ContentLength = 0;
                httpContext.Response.StatusCode    = 400; //TODO!
            }

            var content = await _DbContext.SafeGetContent(genericContentName, id);

            if (content == null)
            {
                //TODO tell CDN to ignore hunting?
                _Logger.LogError($"Content not found - {id}.");
                httpContext.Response.StatusCode    = 404;
                httpContext.Response.ContentLength = 0;
                return;
            }

            if (etagValue == content.PublishingId)
            {
                _Logger.LogWarning($"Matching etag found, responding with 304 - {id}.");
                httpContext.Response.StatusCode    = 304;
                httpContext.Response.ContentLength = 0;
                return;
            }

            //var accepts = httpContext.Request.Headers["accept"].ToHashSet();
            //var signedResponse = content.SignedContentTypeName != null && accepts.Contains(content.SignedContentTypeName);

            //if (!signedResponse && !accepts.Contains(content.ContentTypeName))
            //{
            //    _Logger.LogWarning($"Cannot give acceptable response, responding with 406 - {id}.");
            //    httpContext.Response.StatusCode = 406;
            //    httpContext.Response.ContentLength = 0;
            //    return;
            //}

            httpContext.Response.Headers.Add("etag", content.PublishingId);
            httpContext.Response.Headers.Add("last-modified", content.Release.ToUniversalTime().ToString("r"));
            httpContext.Response.Headers.Add("content-type", content.ContentTypeName);
            httpContext.Response.Headers.Add("cache-control", _HttpResponseHeaderConfig.ImmutableContentCacheControl);
            httpContext.Response.StatusCode    = 200;
            httpContext.Response.ContentLength = content.Content?.Length ?? throw new InvalidOperationException("SignedContent empty.");
            await httpContext.Response.Body.WriteAsync(content.Content);
        }