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 are not exporting anything in the app.js file. At the end of app.js file, include following line.

module.exports = app;

See whether your problem goes away.

And one more addition: you have var app = express(); twice in your app.js.