Configulator

Handles building a config object based on the environment in which the program is running and allows you to override config properties by passing arguments over the command line.

Overview

Does your app run in multiple environments? If so, you more than likely have different settings per environment. This module was created to ease the creation of configuration properties within multiple environments. The common properties that do not change exist within the default property while the environment specific values live within their respective environment property. Now, you can easily load the appropriate configuration based on your environment with a single line of code.

Usage

Getting the environment specific configiuration is simple. Follow these steps:

• Set the node environment variable, NODE_ENV to be the environment your program will be working in. While you are developing, this will most likely be the development environment.
• Define your default and environment specific configurations in your config file. The name of the file is not important as you should use dependency injection to inject the configuration file to your modules. Here is an example configuration:

config.js
/*jshint node: true*/
'use strict';

exports.wiretree = function configModule(configulator) {
  var config = {
    default: {
      status: {
        SUCCESS: 200,
        CREATED: 201,
        BAD_REQUEST: 400,
        NOT_FOUND: 404,
        INTERNAL_SERVER_ERROR: 500
      },
      methods: {
        GET: 'GET',
        PUT: 'PUT',
        POST: 'POST',
        DELETE: 'DELETE',
        PATCH: 'PATCH'
      },
      standardHeaders: {
        'Content-Type': 'application/json'
      },
      port: 8888,
    },
    development: {
      port: 8000
    },
    production: {
      port: 8001
    }
  };

  return configulator(config);
};

Note that in the above example I am using wiretree to inject configulator. You could require it as a dependency if you choose, but I recommend using a dependency injection framework, such as wiretree. It's simple to setup. Just update your tree as follows:

var Wiretree = require('wiretree');
var wireTree = new Wiretree(__dirname);
var configulator = require('configulator');
wireTree.add(configulator, 'configulator');

In the example above, if you set NODE_ENV to be development, it will overwrite the port to be 8000 instead of 8888.

Overwriting values using arguments

You can also overwrite values using arguments. To do this, simply set your specified argument on overrides. For example:

	node myProgram.js --overrides.port=5827

This will override your environment settings and set the port to 5827, regardless of the environment you are running in.