Description

Files which will be required (all files can be defined as JSON and .js CommonJS module):

• If environment is undefined or 'development':
  1. /config/all
  2. /config/development
  3. /config/properties
• Else:
  1. /config/all
  2. /config/properties

The later required files overwrites the others. If an attribute is defined as array, the complete attribute will be overwritten.

Example

const config = require('mxd-config')();
// if the environment is later needed use 'config.environment' 

Configuration

The environment will be defined by NODE_ENV but can be overwritten:

const config = require('mxd-config')('development');

Additional filenames (located in the config directory) can be defined, which also will be loaded:

const config = require('mxd-config')(['lambda']);

If both (environment and additional filenames) are needed, use a config object:

const config = require('mxd-config')({ 
  environment: 'development',
  filenames: ['lambda'], 
});

dotenv

This module silently loads /.env.<NODE_ENV> configs in the project root, e.g. /.env.production if one is found. As a result, we can simply start the app using NODE_ENV=test node app.js which loads /.env.test into the config.

For development purposes, the module also silently loads a "generic" /.env, config regardless of the environment. The variables contained here override those in /.env.<NODE_ENV>.

Environment Getters

Using environment getters, we can get environment variables and cast a type and a default value on them:

const { getBool, getInt, getList, getStr } = require('mxd-config').util;

module.exports = {
  myBool: getBool('MY_BOOL', true),
  myInteger: getInt('MY_INT', 123),
  myString: getStr('MY_STRING', 'foo'),
  myList: getList('MY_LIST', ['foo', 'bar', 'baz'])
};

With no environment variables set, this outputs

{
  myBool: true,
  myInteger: 123,
  myString: 'foo',
  myList: ['foo', 'bar', 'baz']
}

Here's an example .env.development file:

MY_BOOL=off
MY_INT=456
MY_STRING=bar
MY_LIST=baz|bar|foo

This outputs

{
  myBool: false,
  myInteger: 456,
  myString: 'bar',
  myList: ['baz', 'bar', 'foo']
}