good-env

good-env

🚨 v7 requires Node version 18.20.4 or higher! 🚨

good-env provides a more intuitive way to interface with environment variables for node apps. Reasoning about raw strings is OK for some things but for non-trivial applications, booleans, numbers, lists or even the existence (or non-existence) of environment configurations can play a key role in how an application behaves. Lastly, good-env has no production dependencies.

$ npm install good-env --save

With normal process.env

$ export HOST=localhost
$ export SECRET=shhh
$ export FOO=10
$ export A_TRUE_VAL=true
$ export A_FALSE_VAL=false
$ export LIST=foo,bar,bang
$ export ENDPOINT=https://foo.com
$ node
> process.env.FOO
'10'
> process.env.A_TRUE_VAL
'true'
> process.env.A_FALSE_VAL
'false'
> process.env.LIST
'foo,bar,bang'
>

Using good-env

const env = require('good-env')
env.getNumber('FOO') // 10
env.getBool('A_TRUE_VAL') // true
env.getBool('A_FALSE_VAL') // false

Warning Checking the existence of a boolean value which resolves to false will return true because ok() doesn't give you a value.

export A_BOOL_VAL=false

env.ok('A_BOOL_VAL') // true

Specify defaults

env.get('NOT_SET', 'foo') // 'foo'

Batch Gets

env.getAll(['SECRET', 'HOST']) // ['shhh', 'localhost']

// defaults work here too
env.getAll({
  A_SECRET: 'lolz', 
  HOST: null // null means no default
}) // { A_SECRET: 'lolz', HOST: 'localhost' }

Use the first available environment variable

// old and busted
const host = process.env.THE_HOST || process.env.HOST // 'localhost'

// new hotness
const host = env.get(['THE_HOST', 'HOST']) // 'localhost'

// works with defaults
const host = env.get(['THE_HOST', 'A_HOST'], 'localhost') // 'localhost'

Lists

env.getList('LIST') // ['foo', 'bar', 'bang']
env.getList('LIST_NOT_SET') // []

Number Lists

$ export LIST=1,2,3

process.env.LIST // '1,2,3'
env.list('LIST', { cast: 'number' }) // [1, 2, 3]

Sometimes you just need to know if something exists

env.ok('NOT_SET') // false
env.ok('FOO') // true

// works with multiple arguments.
// Returns true if ALL keys exist
env.ok('FOO', 'BAR') // true
env.ok('FOO', 'BAR', 'NOT_SET') // false

Use .assert(item1, item2...) to check the existence and/or type of a few items at once Note: If any variable passed to assert() doesn't exist or is otherwise invalid, an error will be thrown.

env.assert(
    // Will ensure 'HOSTNAME' exists
    'HOSTNAME',
    
    // Will ensure 'PORT' both exists and is a number
    { 'PORT': { type: 'number' }},
    
    // Will ensure 'INTERVAL' exists, it's a number and its value is greater
    // than or equal to 1000
    { 'INTERVAL': { type: 'number', ok: s => s >= 1000 }}
    
    // ... any number of arguments
)

Fetch AWS Credentials

const {
  awsKeyId,
  awsSecretAccessKey,
  awsRegion,
} = env.getAWS();

// Use a default region
const {
  awsKeyId,
  awsSecretAccessKey,
  awsRegion,
} = env.getAWS({ region: 'region' });

Fetch URL objects from url strings

  env.getUrl('ENDPOINT')
  /*
  {
    httpOk: true,
    href: 'https://foo.com/',
    raw: URL {
      href: 'https://foo.com/',
      origin: 'https://foo.com',
      protocol: 'https:',
      username: '',
      password: '',
      host: 'foo.com',
      hostname: 'foo.com',
      port: '',
      pathname: '/',
      search: '',
      searchParams: URLSearchParams {},
      hash: ''
    }  
  }
  */

  env.getUrl('FAKE_ENDPOINT') // null

  // It works with defaults
  env.getUrl('FAKE_ENDPOINT', 'http://localhost:3000')
  /*
  {
    httpOk: true,
    href: 'http://localhost:3000/',
    raw: URL {
      href: 'http://localhost:3000/',
      origin: 'http://localhost:3000',
      protocol: 'http:',
      username: '',
      password: '',
      host: 'localhost:3000',
      hostname: 'localhost',
      port: '3000',
      pathname: '/',
      search: '',
      searchParams: URLSearchParams {},
      hash: ''
    }
  }
  */

About URLs

Why would one use env.getUrl() if one just wishes to grab the url string value? The best reason to use getUrl() and grab the href property is that env.get() doesn't care about the format of the value. Using getUrl() will ensure the url is properly formatted and return a null value if it isn't. In practice, having an invalid url is the same as having no value at all. Then again, it's your code. Do what you want!

As of now, http, redis and postgresql are the only supported protocols. Other protocols will return null. I'm not against adding new protocol support, but these are the ones that seemed most obvious to me. If you want other protocols supported, I'd recommend making a PR. You may create an issue, but I can't guarantee when I'll get around to implementation.

Shortcut Methods

env.num() ==> env.getNumber()
env.bool() ==> env.getBool()
env.list() ==> env.getList()
env.url() ==> env.getUrl()