Rainbow Config

YAML config files made simple for TypeScript and JavaScript using ESM.

Changelog

Version 3.x

• The path is now passed to the load() method instead of the constructor
• The load() method has now one argument: the path
• The library was re-implemented using TypeScript and exports types
• The library can still be used using JavaScript

Example config file

The DBs host and password are loaded either from a secrets file or from environment variables.

config/development.yml

db:
    main
        port: 5432
        host: ${DB_HOST}
        password: ${MAIN_DB_PASS}
myKey: myValue
anArray
    - itemOne
    - itemTwo

secrets.development.yml

DB_HOST: l.dns.porn
MAIN_DB_PASS: soSecureICantBelieveIt

Environments

The config loader decides based on the environment which config file to load. The following default environments are available (alternative names):

• development (dev)
• testing (test)
• integration (int)
• production (prod)

The environment can either be set by passing it as parameter to the application (e.g. --develpment) or by defining it in the RAINBOW_ENV or NODE_ENV environment variable.

Based on the configured environment the config file is loaded. If the development environment is active, the loader tries to load the config/development.yml file.

Example

It is based on the example config above.

import RainbowConfig from '@rainbow-config/RainbowConfig';
import { URL } from 'url';
import path from 'path';

const config = new RainbowConfig();

// you may add custom environments
config.addEnvironment('extra-env');

// you may load the config from a custom directory, default is config
config.setConfigDir('conf');

// get the directory where the config filder is located in
const rootdir = path.join(path.dirname(new URL(import.meta.url).pathname, '../');

// load the config file (the secrets dir parameter is optional)
await config.load(rootdir, secretsDir);

// get the full config object
const allKeys = config.get();

// get the db password
const dbPassword = config.get('db.main.password');

// prints: soSecureICantBelieveIt
console.log(dbPassword);

API

Constructor: instantiate the config class

The constructor accepts optionaly the environment name asparameter 1

const config = new RainbowConfig();

Add an environment: config.addEnvironment(name: string)

You may optionally add an environment. You may also specify an alternative name that maps to the environment name i.e. int for integration.

The follwoing envormnents are available (alternative names):

• development (dev)
• testing (test)
• integration (int)
• production (prod)

config.addEnvironment('extra-env', 'alternative-name-for-extra-env');

Change the config directory: config.setConfigDir(relativePath: string)

You may change the directory the config files are located in. This defaults to config.

config.setConfigDir('conf');

Load the confguration: config.load(rootDir: string, secretsDir?: string)

In order to load the config, you have to call the load method. This will load the config from the ${rootPath}/config directory. This will load the config file an fill all variables that are either set in the environment or the secrets file. If a variable is not found in an env variable, it is assumed, that it shall be loaded from the secrets file, which is located in the rootPath passed to the load(rootPath: string) method. The secrets file has the name secrets.${environment}.yaml. If the secretsDir is passed to the load method, that directory will be used to load the secrets.

const rootdir = path.join(path.dirname(new URL(import.meta.url).pathname, '../');
await config.load(rootdir);

Get a config value: config.get(path: string | undefined)

Get the complete config object.

const configData = config.get(undefined);

Get the a partial config object

const configData = config.get(`db.main`);

Get the a specific key

const configData = config.get(`db.main.password`);