Express-subdomain simple setup not working

问题:

I made a few modifications to the example 'Divide and Conquer' section on the npm docs: https://www.npmjs.com/package/express-subdomain

const subdomain = require('express-subdomain');
const express = require('express');
const app = express();
var router = express.Router(); //main api router
var v1Routes = express.Router();

v1Routes.get('/test', function(req, res) {
    res.send('API - version 1');
});

router.use(subdomain('api', v1Routes));

//basic routing..
router.get('/', function(req, res) {
    res.send('Welcome to the API!');
});

//attach the api
app.use(subdomain('api', router));
app.listen(8000);

console.log("listening on 8000")

Basically, I got rid of the v2 routes and changed the subdomain on the v1 routes to just api. I also got rid of the middleware and changed the v1 route to /test just to differentiate it from the basic routing.

Also my /etc/hosts file looks like this:

127.0.0.1       myapp.dev
127.0.0.1       api.myapp.dev
255.255.255.255 broadcasthost
::1             localhost

The only thing I did there is change localhost to myapp.dev and added api.myapp.dev, which I found here: https://github.com/bmullan91/express-subdomain#developing-locally

Any ideas?