dotconfig

Config helper to (magically) override application settings with environment variables.

Comes packaged with a dotenv file loader.

Works with dotenvx encrypted .env files and its .env.keys file. Uses same secp256k1 encryption.

Comes bundled with a helper CLI to encryt and decrypt environment variables more easily. See Encryption

Install

Add to your project:

npm i @commenthol/dotconfig

Usage

File: ./config.js

import { dotconfig } from '@commenthol/dotconfig'

// loads process env vars from .env file and process env-vars
export const config = dotconfig({
  port: 8080,
  http: {
    proxy: undefined,
  },
  https: {
    cert: '',
    key: ''
  },
  sso: {
    serverUrl: 'https://my.sso',
    clientId: 'myClientId',
    clientSecret: undefined,
  },
  isProd: false,
  names: [], // arrays must be defined!
  user: { 
    __group: true // groups env vars into object
                  // Here env-var MUST have min 3 parts with min 2 dashes!
  },
  // if loading from file default config var must contain at least `file://`
  loadFile: 'file://',
})

with file: ./.env

export PORT=3000
export HTTP_PROXY=my-proxy:1234
export SSO_SERVER_URL=https://other.sso/path
export SSO_CLIENT_SECRET=ƚɘɿƆɘƧ
export NAMES_0=Alice
export NAMES_1=Bob
export NAMES_2=Charlie
export USER_0_USERNAME=Alice
export USER_0_PASSWORD="correct horse battery staple"
export USER_1_USERNAME=Bob
export USER_1_PASSWORD=ʇǝɹɔǝs
export IS_PROD=true
export ANY_OTHER_VALUE=1234
# Multi line values are supported (set them in quotes!)
export HTTPS_KEY="-----BEGIN PRIVATE KEY-----
MIIE...
-----END PRIVATE KEY-----"
export HTTPS_CERT='-----BEGIN CERTIFICATE-----
MIID...
-----END CERTIFICATE-----'
# loads content from file relative: `file://./relative` absolute: `file:///absolute`
export LOAD_FILE='file://./cert.key'
# use encrypted values together with a .env.keys file containing DOTENV_PRIVATE_KEY
DOTENV_PUBLIC_KEY="03d599cf2e4febf5e149ab727132117314a640e560f0d5c2395742e8219e9dbeee"
HELLO="encrypted:BOyGm1Oug6X4b+...wtJ2/j7+PtP1nThQ6YCw"

results in config being exported as

const config = {
  http: {
    proxy: 'my-proxy:1234',
  },
  https: {
    key: '-----BEGIN PRIVATE KEY-----\nMIIE...\n-----END PRIVATE KEY-----',
    cert: '-----BEGIN CERTIFICATE-----\nMIID...\n-----END CERTIFICATE-----'
  },
  port: 3000,
  sso: {
    serverUrl: 'https://other.sso/path',
    clientId: 'myClientId',
    clientSecret: 'ƚɘɿƆɘƧ',
  },
  names: ['Alice', 'Bob', 'Charlie'],
  user: {
    0: {
      username: 'Alice',
      password: 'correct horse battery staple'
    },
    1: {
      username: 'Bob',
      password: 'ʇǝɹɔǝs'
    }
  },
  isProd: true,
  anyOtherValue: '1234',
  // the content from `LOAD_FILE`
  loadFile: '-----BEGIN PRIVATE KEY-----\nMIIE...\n-----END PRIVATE KEY-----',
  // decrypted values nor private keys show up in `process.env` object
  hello: 'world'
}

Encryption

Can work with dotenvx encrypted .env files for handling value encryption.

Comes bundled with own CLI to handle encryption of values in .env files:

# add package to your project first
npm i @commenthol/dotconfig
# get some help
npx dotconfig --help
# create a new .env file with encrypted value "foo"
npx dotconfig encrypt foo bar
# lookup decrypted value on stdout
npx dotconfig decrypt foo --stdout

ℹ️ NOTE: Never commit your .env.keys file. Keep it in a save place.

To use a different .env.keys file you may use DOTENV_PRIVATE_KEYS_PATH env-var.

Decrypted values only appear in the config object but never in process.env. Private keys are also only used internally for decryption and are deleted if they appear in process.env.

API

dotconfig

dotconfig calls dotenv.config() first before passing the parsed process.env variables through getConfig().

Types

function dotconfig(
    /**
     * The default configuration object
     */
    defaultConfig: object, 
    /**
     * optional configuration options.
     */
    options?: DotConfigOptions
): Record<string, any> | {};

type DotConfigOptions = {
    /**
     * The path to the dotenv file. Default is '.env' in the current working 
     * directory. May be set via DOTENV_CONFIG_PATH env var.
     */
    path?: string | URL | undefined;
    /**
     * The encoding of the dotenv file. 
     * May be set via DOTENV_CONFIG_ENCODING env var.
     */
    encoding?: BufferEncoding | undefined;
    /**
     * Whether to override existing process environment variables. 
     * Default is false. May be set with DOTENV_CONFIG_OVERRIDE=true env var.
     */
    override?: boolean | undefined;
    /**
     * The process environment object to update. Default is `process.env`.
     */
    processEnv?: NodeJS.ProcessEnv | object;
    /**
     * if `false` do not add additional props on top-level not part of defaultConfig
     */
    additionalProps?: boolean | undefined;
    /**
     * if `false` do not add any additional props that are not part of defaultConfig
     */
    additionalPropsAll?: boolean | undefined;
    /**
     * default=true; Throw on decryption error
     */
    throwOnDecryptionError?: boolean | undefined;
};

dotenv

dotenv comes with two methods parse() and config().

dotenv.config() returns the parsed .env file (if found).

Usage

import { dotenv } from '@commenthol/dotconfig'

// loads `.env` in current working directory
dotenv.config()

// loads `.env-local` relative to file
dotenv.config({ 
  path: new URL('./.env-local', import.meta.url)
})

Types

function config (
  /**
   * optional configuration options.
   * see types above at dotconfig.
   */
  options?: DotenvConfigOptions
): ConfigResult;

type DotenvConfigOptions = {
    /**
     * The path to the dotenv file. Default is '.env' in the current working directory. May be set via DOTENV_CONFIG_PATH env var.
     */
    path?: string | URL | undefined;
    /**
     * The encoding of the dotenv file. May be set via DOTENV_CONFIG_ENCODING env var.
     */
    encoding?: BufferEncoding | undefined;
    /**
     * Whether to override existing process environment variables. Default is false. May be set by DOTENV_CONFIG_OVERRIDE env var.
     */
    override?: boolean | undefined;
    /**
     * The process environment object to update. Default is `process.env`.
     */
    processEnv?: NodeJS.ProcessEnv | object;
};

export type ConfigResult = {
    /** parsed .env file */
    parsed: Record<string, string | number | boolean> | {};
};

getConfig

Applies the lower camel-cased process.env variables onto the default configuration.

Usage

import { getConfig } from '@commenthol/dotconfig'

process.env.HTTP_PORT = '8080'
process.env.HTTPS_PORT = '8443'

const config = getConfig({
  http: { port: 80 },
  https: { port: 443 }
})
//> config = {
//>  http: { port: 8080 },
//>  https: { port: 8443 }
//> }

License

MIT licensed