node.js - How exactly does eval work with nodejs? -

let's do:

eval(  db_config = {                         host: 'localhost',                         user: 'root',                         database: 'forum',                         password: 'test'                     } );   var gamefunctions = require('gamefunctions.js'); 

i can use db_config anywhere inside gamefunctions.js without having pass through parameter. that's pretty neat. but, bad practice?

reason ask because if do:

 var db_config = {                         host: 'localhost',                         user: 'root',                         database: 'forum',                         password: 'test'                     }    var gamefunctions = require('gamefunctions.js'); 

db_config becomes undefined anytime use in gamefunctions.js. , have pass through parameter on each different function seems evaling first save time , code, downside this?

does eval define variables in global scope you, can used in file in nodejs?

you're doing 2 things wrong , there's more elegant solution this.

to explain you're doing wrong, first use of globals. second you're storing sensitive information in code - database password! , besides, won't portable. suppose want run on machine has other database credentials you'll end changing code unnecessarily.

you need store environment variables. , if end hosting environments automatically have set use them in app. example openshift have $openshift_mongodb_db_host tells use in app connect database.

and need create separate file store db_config can require other files.

so might create db_config.js this

var config = {}; config.host = process.env.host || 'localhost'; config.user = process.env.user || 'root'; config.password = process.env.password; module.exports = config; 

then can safely pass sensitive information password console

$ password=pass $ node index.js 

and having information in gamefunctions.js gotta require it

var db_config = require('./db_config');