ExpressJS strict routing workaround

strict-routing.js

/*
Enforcing strict routing

https://github.com/expressjs/express/issues/2281

Use cases:

GET /strict -> noslash
GET /strict/ -> noslash (expect slash)
GET /strict// -> noslash (expect 404)
GET /strictslash -> noslash (expect 404)
GET /strictslash/ -> noslash
GET /strictslash// -> noslash (expect 404 or slash - not sure)
GET /strictslash/// -> noslash (expect 404)
//*/
const express = require("express");

const app = express();
app.set("strict routing", true);

const router = express.Router({ strict: true });

//  Middleware to enforce strict URLs
router.use(function strict(req, res, next) {
  if (req.app.get("strict routing")) {
    req.url = req.originalUrl.substring(req.baseUrl.length);
  }
  next();
});

//  Note: using .use() will not work:
//  router.use("", function (req, res, next) {
router.all("", function (req, res, next) {
  res.send("noslash");
});

//  Note: using .use() will not work:
//  router.use("", function (req, res, next) {
router.all("/", function(req, res) {
    res.send("slash");
});

app.use("/strict", router);
app.use("/strictslash/", router);

app.listen(4000);