bestest

  middleware = fn(req) → next(req).

  type mw = (req: Request, next: () => Response) => Response;
  
  const logger: mw = (req, next) => {
  console.log(req.url);
  return next();

  const auth: mw = (req, next) => {
    if (!req.headers.get("x-auth")) return new   Response("forbidden", { status: 403 });
    return next();
  };
  
  function chain(mws: mw[]) {
    return (req: Request) =>
      mws.reduceRight((next, mw) => () => mw(req, next), () => new Response("ok"))();
  }
  
  export function middleware(req: Request) {
    return chain([logger, auth])(req);
  }