app.set('port', port) 'TypeError: undefined is not a function'. Beginner, need ideas

Question

I\'m an amateur learning to build with node.js. I\'ve been following a tutorial to create my first node.js app. It worked perfectly until I entered \'npm start\'. The log is:

Answer 1

You don't have declared any function called set inside the app.js file. Create that function and export it like this:

exports.set = function(...) { ... };

If this app is the express app yo especify a port like this:

var express = require('express'),
    http = require('http');

var app = express();

http.createServer(app).listen(port);

instead of

app.set('port', port);
 /**
 * Create HTTP server.
 */

var server = http.createServer(app);

This is because the port is a property of the http server and not of the express app

You can use also

var express = require('express'),
    app = express();

app.listen(port);