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Load YAML configs based on current node environment.


Let's say you have this kind of config setup:

  config.yml              // Shared configuration          // Extended dev configuration
  config.production.yml   // Extended production configuration

Then ConfigLoader can help you load these based on current environment. Let's say you are running node in a development environment by setting NODE_ENV:

$ NODE_ENV=dev node yourapp.js

ConfigLoader would then load up config.yml and extend it with

Your config.yml might look like this:

  title: My Awesome Site
  port: 80

And your might look like this:

  port: 1337
  user: root
  pass: IAMMEGAHAxx00r

The loaded configuration would then be:

{ site: { title: "My Awesome Site" },
  http: { port: 1337 },
  database: { user: 'root', pass: 'IAMMEGAHAxx00r' }


ConfigLoader is one single function that behaves a bit differently depending on what arguments you give it.

Loading configurations synchronously

If you do not give ConfigLoader a callback function it will do the loading synchronously.

var configloader = require('configloader');
var config = configloader('path/to/configs');

If path/to/configs does not contain any files matching the requirements an error will be thrown if loading is done synchronously.

Loading configurations asynchronously

If you do give ConfigLoader a callback function it will return the loaded configuration to that function.

var configloader = require('condigloader');
configloader('path/to/configs', function (err, config) {
  if (err) {
    console.log('had an error :(');

If any of the configuration files contains YAML errors the err argument will be the error from js-yaml.

If no configurations files were found in path/to/configs I think you will get undefined as the second argument. :P

Forcing environment

If you want to force a certain environent to be used you can pass

{ env: 'other-env' }

as a second argument to configloader().


By convention ConfigLoader requires you to name your configuration files using this pattern: config(\.environment)?\.yml

If you'd like to change this pull requests making more use of the options argument are very much welcome!

If ConfigLoader can't find any configured environment it will fall back on dev.


Install with npm: $ npm install configloader


Tests are written using mocha.