fleg
v0.0.3
Published
🎌 A simple but powerful feature flag handling solution in less than 1Kb (min+gz). Browser + NodeJS.
Downloads
19
Readme
Fleg (https://en.wiktionary.org/wiki/fleg)
🎌 A simple but powerful feature flag handling solution.
- Control through Cookies.
- Control through Query String.
- Automatic value conversion.
- Browser support.
- NodeJS support.
- 0 dependency.
- Less than 1Kb (min+gz).
Installation
npm i fleg
Usage
Fleg is meant to be initialized ONLY ONCE!
During bootstrap stage (at the very beginning) of your application, import Fleg and define your initial flags.
import { Fleg } from 'fleg'
new Fleg({
enableFoo: true,
enableBar: false,
stringFlag: 'string'
})
Further on at any other part of the application use the default import. It will be the Fleg instance you created previously.
import fleg from 'fleg'
fleg.enableFoo // true
API
Fleg is extending Map
which means all Map APIs are available. https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map
fleg.get('enableFoo')
fleg.set('enableFoo', false)
// ...
set(key: string|array|object, value: any, writeCookie?: boolean)
Fleg overrides the default set
method of Map
to extend its functionality.
// Passing true will write this flag to cookies
fleg.set('key', 'value', true)
// You may pass an "entries shaped" array
fleg.set([
['key', 'value'],
['foo', 'bar']
])
// Pass object
fleg.set({
enableFoo: 1,
enableBar: 2
})
delete(key: string)
Delete a flag. It'll also remove associated cookies.
fleg.delete('enableFoo')
reset()
Reset flags back to initial state (what was passed to the constructor).
resetFleg
Query String option
For convenience, you can add resetFleg
query string to your URL to remove all cookie flags.
e.g. yourdomain.com?resetFleg
Globals
For convenience, the created Fleg instance can be accessed on the global scope both in NodeJS and the Browser.
global.__fleg
window.__fleg
Layered control
Fleg has 3 layers in the following order of loading:
- Initial flags: what is passed to the constructor.
- Cookie flags: cookie flags will override initial flags.
- Query String flags: will override all other flags AND will also set it as cookie, so it'll remain on next reload.
Contributing
Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change.
Please make sure to update tests as appropriate.