express app server . listen all interfaces instead of localhost only

Question

I\'m very new for this stuff, and trying to make some express app

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

app.listen(3000, function(err) {
         


        

Answer 1

document: app.listen([port[, host[, backlog]]][, callback])

example:

const express = require('express');
const app = express();
app.listen('9000','0.0.0.0',()=>{
      console.log("server is listening on 9000 port");
})

Note: 0.0.0.0 to be given as host in order to access from outside interface

Answer 2

From the documentation: app.listen(port, [hostname], [backlog], [callback])

Binds and listens for connections on the specified host and port. This method is identical to Node’s http.Server.listen().

var express = require('express');
var app = express();
app.listen(3000, '0.0.0.0');

Answer 3

If you use don't specify host while calling app.listen, server will run on all interfaces available i.e on 0.0.0.0

You can bind the IP address using the following code

app.listen(3000, '127.0.0.1');