install.js

var mongoose = require('mongoose'),
    User = require('./models/user'),
    utils = require('./utils/function'),
    config = require('./config'),

    EMAIL,
    PASSWORD,
    stdin = process.stdin, 
    stdout = process.stdout,

    env = process.argv.slice(2)[0] || 'development';

mongoose.connect(config.db[env].uri);

function ask(param) {
 
    var question = param.question,
        validate = param.validate,
        errorMsg = param.errorMsg,
        callback = param.callback;

    stdin.resume();
    stdout.write(question + ": ");

    stdin.once('data', function (data) {
        data = data.toString().trim();

        if ( !validate(data) ){
            stdout.write(errorMsg + "\n");
            ask(param);
        } else {
            callback(data);
        }
    });
}

stdout.write('Welcome to Bookmarks! ' + "\n");
stdout.write('Before to continue, you need to create your account ' + "\n");

ask({
    question: 'Enter your email',
    errorMsg: 'Please, enter a valid email',
    validate: function (email) {
        return utils.isEmail(email);
    },
    callback: function (data) {
        EMAIL = data;
        //ask password
        ask({
            question: 'Enter your password',
            validate: function () {
                return true
            },
            callback: function (data) {
                PASSWORD = data;

                User.remove({},function (err) {
    
                    if (err) {
                        console.log('Error: ' + err);
                    }

                    //Create the admin user
                    var admin = new User({
                        email: EMAIL,
                        password: PASSWORD,
                        passwordConfirm: PASSWORD
                    });

                    admin.save(function (error, user) {
                        stdout.write('Your account has been created ' + "\n");
                        stdout.write('Email: ' + user.email + "\n");
                        stdout.write('Password: ' + PASSWORD);
                        process.exit(1);
                    });
                });
            }
        })
    }
});