illustrate handling middleware

handling-middleware.js

const context = { rq: {}, rp: {} };
const md1 = async ({ rq, rp }, next, args) => {
  console.log("md1 rq", rq);
  console.log("md1 next", next);
  rq.a = 1;
  console.log("md1 args", args);
  await next();
};

const md2 = async ({ rq, rp }, next, args) => {
  console.log("md2 rq", rq);
  console.log("md2 next", next);
  rq.b = 2;
  console.log("md2 args", args);
  await next();
};

const md3 = async ({ rq, rp }, next, args) => {
  console.log("md3 rq", rq);
  console.log("md3 next", next);
  rq.c = 4;
  console.log("md3 args", args);
  await next();
};

const mds = [md1, md2, md3];
(async function () {
  try {
    const mdsRS = mds.reverse();
    mdsRS.forEach((middleWareHandler, index) => {
      if (!index) {
        mdsRS[index] = middleWareHandler.bind(null, context, (context) => {});
      } else {
        mdsRS[index] = middleWareHandler.bind(null, context, mds[index - 1]);
      }
    });

    // Call the first middleware
    if (mdsRS[mdsRS.length - 1]) {
      mdsRS[mdsRS.length - 1]();
    }
    console.log("context change after proccess middleware", context);
    // Process router
    //   await routerHandler(context);
  } catch (err) {
    console.log("err", err);
  }
})();