env-to-object

Environment Variables

Maps environment variables to a configuration object.

Installation

$ npm install env-to-object

Usage

var env = require( 'env-to-object' );

env( map )

Maps environment variables to a configuration object.

var map = {
	'NODE_ENV': {
		'keypath': 'env',
		'type': 'string'
	},
	'PORT': {
		'keypath': 'server.port',
		'type': 'number'
	},
	'SSL': {
		'keypath': 'server.ssl',
		'type': 'boolean'
	},
	'LOGLEVEL': {
		'keypath': 'logger.level',
		'type': 'string'
	}
};

var out = env( map );
/*
	{
		'env': <string>,
		'server': {
			'port': <number>,
			'ssl': <boolean>
		},
		'logger': {
			'level': <string>
		}
	}
*/

An environment variable mapping must include a keypath, which is a dot-delimited object path. By default, this module parses an environment variable value as a string. The following types are supported:

• string: coerce an environment variable value to a string (default).
• number: coerce an environment variable value to a number.
• boolean: coerce an environment variable value to a boolean. The following values are supported:
  • TRUE
  • True
  • true
  • T
  • t
  • FALSE
  • False
  • false
  • F
  • f
• object: parse an environment variable value as a JSON object. Note that a value must be valid JSON.

If an environment variable does not exist, the corresponding configuration keypath will not exist in the output object.

var map = {
	'UNSET_ENV_VAR': {
		'keypath': 'a.b.c'
	}
};

var out = env( map );
// returns {}

Examples

var env = require( 'env-to-object' );

var map = {
	'DEFAULT': {
		'keypath': 'default'
	},
	'STR': {
		'keypath': 'str',
		'type': 'string'
	},
	'NUM': {
		'keypath': 'num',
		'type': 'number'
	},
	'BOOL': {
		'keypath': 'bool',
		'type': 'boolean'
	},
	'ARR': {
		'keypath': 'arr',
		'type': 'object'
	},
	'NESTED': {
		'keypath': 'a.b.c.d',
		'type': 'object'
	}
};

process.env[ 'DEFAULT' ] = 'beep';
process.env[ 'STR' ] = 'boop';
process.env[ 'NUM' ] = '1234.5';
process.env[ 'BOOL' ] = 'true';
process.env[ 'ARR' ] = '[1,2,3,4]';
process.env[ 'NESTED' ] = '{"hello":"world"}';

var out = env( map );
/*
	{
		'default': 'beep',
		'str': 'boop',
		'num': 1234.5,
		'bool': true,
		'arr': [1,2,3,4],
		'a': {
			'b': {
				'c': {
					'd': {
						'hello': 'world'
					}
				}
			}
		}
	}
*/

To run the example code from the top-level application directory,

$ node ./examples/index.js

or, alternatively,

$ DEFAULT=boop STR=beep NUM='5432.1' BOOL='FALSE' ARR='[4,3,2,1]' NESTED='{"world":"hello"}' node ./examples/index.js

Tests

Unit

Unit tests use the Mocha test framework with Chai assertions. To run the tests, execute the following command in the top-level application directory:

$ make test

All new feature development should have corresponding unit tests to validate correct functionality.

Test Coverage

This repository uses Istanbul as its code coverage tool. To generate a test coverage report, execute the following command in the top-level application directory:

$ make test-cov

Istanbul creates a ./reports/coverage directory. To access an HTML version of the report,

$ make view-cov

---

License

MIT license.

Copyright

Copyright © 2015. Athan Reines.