javascript - How to set process env variables in config fle in Node.js -

i need 1 help. need set common global variables in 1 config file , values required using node.js. here need implement process.env. explaining code below first.

var port=8989; var express=require('express'); var morgan = require('morgan'); var http=require('http'); var bodyparser= require('body-parser'); var methodoverride = require('method-override'); var mongo = require('mongojs'); var session = require('express-session'); var multer  = require('multer') var app=module.exports=express(); var server=http.server(app); var admin=require('./route/route.js'); app.use(express.static(__dirname + '/public'));     // set static files location /public/img /img users app.use(morgan('dev'));                     // log every request console app.use(bodyparser.urlencoded({ extended: false }))    // parse application/x-www-form-urlencoded app.use(bodyparser.json())    // parse application/json app.use(methodoverride());                  // simulate delete , put app.use(session({secret: 'fgdplexel',resave: true,saveuninitialized: true})); app.get('/',function(req,res){     res.sendfile(__dirname + '/index.html'); }) var storage =multer.diskstorage({   destination: function (req, file, callback) {     callback(null, './uploads');   },   filename: function (req, file, callback) {     callback(null, file.fieldname + '-' + date.now());   } }); server.listen(port); console.log("server running on port"+port); 

here assigning port=8989 here need create 1 config file , assign variable there. in server.js file include , user required values.please me.

you can use dotenv npm package. requires setup .env file key-value pairs in format key=value secret_key=megasecretkey.

const dotenv = require('dotenv');  dotenv.load({     path: '.env.globals' // example }); 

and can access variables process.env.secret_key