Question

How do i set a variable in app.js and have it be available in all the routes, atleast in the index.js file located in routes. using the express framework and node.js

Answer 1

To make a global variable, just declare it without the var keyword. (Generally speaking this isn’t best practice, but in some cases it can be useful – just be careful as it will make the variable available everywhere.)

Here’s an example from visionmedia/screenshot-app

file app.js:

/**
 * Module dependencies.
 */

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

app = express();

//... require() route files

file routes/main.js

//we can now access 'app' without redeclaring it or passing it in...

/*
 * GET home page.
 */

app.get('/', function(req, res, next){
  res.render('index');
});

//...