Node.js-Express Help: why do the changes I make in the code don't take effect when I run it?

1

This is very odd. Any idea why that could happen?
I save the files (Atom) and do ‘npm start’ again.

2

I think we’d really need to see the code, and what the expected behavior is versus what you are coding.

I assume you are testing endpoints? Is is possible you have more than one server running and you are testing the old one?

3

I’ll try to paste only the relevant parts and not the trivial code:

app.js:

var shortenerRouter = require('./routes/index');
var app = express();
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'jade');

app.use(logger('dev'));
app.use(express.json());
app.use(express.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));

app.use('/', shortenerRouter);

routes/index.js:

const shortenerRouter = express.Router();

shortenerRouter.use(bodyParser.json());

shortenerRouter.route('/')
.get(function(req, res, next) {
  console.log(".get")
  //res.render('index', { title: 'Express' });
  res.json({user: "moi"})
})

It should return “moi” but instead it displays the static index page.

4

OK, I wasn’t able to get what you have working. When I initialize an npm package, change your files to:

App.js

const express = require('express');
const path = require('path');
const logger = require('morgan');
const cookieParser = require('cookie-parser');

var shortenerRouter = require('./routes/index');
var app = express();
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'jade');

app.use(logger('dev'));
app.use(express.json());
app.use(express.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));

app.use('/', shortenerRouter);

const PORT = 8080;

app.listen(PORT)
  .on('listening', () => {
    console.clear();
    console.log('server listening on port:', PORT);
  })
  .on('error', (err) => {
    console.error('### error opening port:', PORT);
    console.error(err);
  });

and index.js

const express = require('express');
const bodyParser = require('body-parser');
const shortenerRouter = express.Router();

shortenerRouter.route('/')
.get(function(req, res, next) {
  res.json({user: "hey"})
})

module.exports = shortenerRouter;

and install the relevant packages with something like:
npm i -S express body-parser morgan cookie-parser

then it works. I can change the return value in the route, restart the server, and get the new data by putting http://localhost:8080/ in the browser address.

You were missing some of the package imports. I had to guess which logger you were using, and I had to export your router - but with that it works.

Instead of using node to run your server, I might suggest installing the very common and helpful nodemon:

npm install -g nodemon

Then you run your app:

nodemon App.js

and it will restart the server for you when you make changes.

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