source: TFP-WebServer/WebServer/src/UrlHandlers/RewriteHandler.cs@ 486

namespace Webserver.UrlHandlers {
        public class RewriteHandler : AbsHandler {
                private readonly string target;
                private readonly bool fixedTarget;

                public RewriteHandler (string _target, bool _fixedTarget = false) : base (null) {
                        target = _target;
                        fixedTarget = _fixedTarget;
                }

                public override void HandleRequest (RequestContext _context) {
                        _context.RequestPath = fixedTarget ? target : $"{target}{_context.RequestPath.Remove (0, urlBasePath.Length)}";
                        parent.ApplyPathHandler (_context);
                }
        }
}