gistfile1.js

var express = require("express"),
    nonAuthRouter = express.Router(),
    authRouter = express.Router(),
    app = express();

authRouter.use(function (req, res, next) {
    console.log("This is a routers");
    next();
});

nonAuthRouter.get("/foo", function (req, res) {
    console.log("foo");
    res.end();
});
authRouter.get("/bar", function (req, res) {
    console.log("bar");
    res.end();
});

app.use(nonAuthRouter);
app.use(authRouter);
app.listen(process.env.PORT);