public IResponse?Handle(IRequest request) { string?sitemapUrl = null; if (Sitemap != null) { if (!Sitemap.StartsWith("http")) { var protocol = request.Client.Protocol.ToString().ToLower(); var normalized = Sitemap.StartsWith("/") ? Sitemap.Substring(1) : Sitemap; sitemapUrl = $"{protocol}://{request.Host}/{normalized}"; } else { sitemapUrl = Sitemap; } } return(request.Respond() .Type(ContentType.TextPlain) .Content(new RobotsContent(Directives, sitemapUrl)) .Build()); }