App.set('port', Port) 'typeerror: Undefined Is Not A Function'. Beginner, Need Ideas

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: C:\node\

Solution 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.

Solution 2:

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);

Solution 3:

Intaned of calling export please use module.export end the end of your script.

exports = app;module.exports = app;

Solution 4:

At the bottom of your app.js:

app.set('port', process.env.PORT || 26398); //<--- replace with your port number// Servervar server = http.createServer(app);
server.listen(app.get('port'), function(){
    console.log('Express server listening on port ' + app.get('port'));
});

module.exports = app;

Solution 5:

In my case I simply moved the normalizePort function before the function was called. This was in coffeescript but I've converted it to javascript here.

normalizePort = function(val) {
  var port;
  var port;
  port = parseInt(val, 10);
  if (isNaN(port)) {
    returnval;
  }
  if (port >= 0) {
    return port;
  }
  returnfalse;
};

port = normalizePort(process.env.PORT || '4000');