Node.js setting up environment specific configs to be used with everyauth

Question

My solution,

load the app using

NODE_ENV=production node app.js

Then setup config.js as a function rather than an object

module.exports = function(){
    switch(process.env.NODE_ENV){
        case 'development':
            return {dev setting};

        case 'production':
            return {prod settings};

        default:
            return {error or other settings};
    }
};

Then as per Jans solution load the file and create a new instance which we could pass in a value if needed, in this case process.env.NODE_ENV is global so not needed.

var Config = require('./conf'),
    conf = new Config();

Then we can access the config object properties exactly as before

conf.twitter.consumerKey

You could also have a JSON file with NODE_ENV as the top level. IMO, this is a better way to express configuration settings (as opposed to using a script that returns settings).

var config = require('./env.json')[process.env.NODE_ENV || 'development'];

Example for env.json:

{
    "development": {
        "MONGO_URI": "mongodb://localhost/test",
        "MONGO_OPTIONS": { "db": { "safe": true } }
    },
    "production": {
        "MONGO_URI": "mongodb://localhost/production",
        "MONGO_OPTIONS": { "db": { "safe": true } }
    }
}

A very useful solution is use the config module.

after install the module:

$ npm install config

You could create a default.json configuration file. (you could use JSON or JS object using extension .json5 )

For example

$ vi config/default.json

{
  "name": "My App Name",
  "configPath": "/my/default/path",
  "port": 3000
}

This default configuration could be override by environment config file or a local config file for a local develop environment:

production.json could be:

{
  "configPath": "/my/production/path",
  "port": 8080
}

development.json could be:

{
  "configPath": "/my/development/path",
  "port": 8081
}

In your local PC you could have a local.json that override all environment, or you could have a specific local configuration as local-production.json or local-development.json.

The full list of load order.

Inside your App

In your app you only need to require config and the needed attribute.

var conf = require('config'); // it loads the right file
var login = require('./lib/everyauthLogin', {configPath: conf.get('configPath'));

Load the App

load the app using:

NODE_ENV=production node app.js

or setting the correct environment with forever or pm2

Forever:

NODE_ENV=production forever [flags] start app.js [app_flags]

PM2 (via shell):

export NODE_ENV=staging
pm2 start app.js

PM2 (via .json):

process.json

{
   "apps" : [{
    "name": "My App",
    "script": "worker.js",
    "env": {
      "NODE_ENV": "development",
    },
    "env_production" : {
       "NODE_ENV": "production"
    }
  }]
}

And then

$ pm2 start process.json --env production

This solution is very clean and it makes easy set different config files for Production/Staging/Development environment and for local setting too.

In brief

This kind of a setup is simple and elegant :

env.json

{
  "development": {
      "facebook_app_id": "facebook_dummy_dev_app_id",
      "facebook_app_secret": "facebook_dummy_dev_app_secret",
  }, 
  "production": {
      "facebook_app_id": "facebook_dummy_prod_app_id",
      "facebook_app_secret": "facebook_dummy_prod_app_secret",
  }
}

common.js

var env = require('env.json');

exports.config = function() {
  var node_env = process.env.NODE_ENV || 'development';
  return env[node_env];
};

app.js

var common = require('./routes/common')
var config = common.config();

var facebook_app_id = config.facebook_app_id;
// do something with facebook_app_id

---

To run in production mode : $ NODE_ENV=production node app.js

---

In detail

This solution is from : http://himanshu.gilani.info/blog/2012/09/26/bootstraping-a-node-dot-js-app-for-dev-slash-prod-environment/, check it out for more detail.

The way we do this is by passing an argument in when starting the app with the environment. For instance:

node app.js -c dev

In app.js we then load dev.js as our configuration file. You can parse these options with optparse-js.

Now you have some core modules that are depending on this config file. When you write them as such:

var Workspace = module.exports = function(config) {
    if (config) {
         // do something;
    }
}

(function () {
    this.methodOnWorkspace = function () {

    };
}).call(Workspace.prototype);

And you can call it then in app.js like:

var Workspace = require("workspace");
this.workspace = new Workspace(config);

An elegant way is to use .env file to locally override production settings. No need for command line switches. No need for all those commas and brackets in a config.json file. See my answer here

Example: on my machine the .env file is this:

NODE_ENV=dev
TWITTER_AUTH_TOKEN=something-needed-for-api-calls

My local .env overrides any environment variables. But on the staging or production servers (maybe they're on heroku.com) the environment variables are pre-set to stage NODE_ENV=stage or production NODE_ENV=prod.