Creature Features

  

!creature features

Dead simple feature flags

Creature-Features allows feature flags based on json configuration files and supports true/false, custom rules, and weighted checks.

$3

``bash

npm install creature-features --save
`

$3

#### directory and files

`

- features
-- default.json (default settings)
-- development.json (settings for development environment)
-- development.{named}.json (settings for individual development environment)
-- test.json (settings for test)
-- production.json (settigns for production)
-- {any other environment}.json
`

#### Example File

`json

{
"FeatureOne": true,
"FeatureTwo": true,
"FeatureThree": false
}
`

$3

`javascript

const features = require('creature-features')();
// Default behavior
if (features.FeatureOne) {
// do something new
} else {
// do the old thing
}
`
#### Rules Based
`json

{
"FeatureOne": true,
"FeatureTwo": true,
"RuleForEmailFeature": {
"parameters": "email",
"check": "email.indexOf('test') > -1"
},
"RuleForEmailAndRoleFeature": {
"parameters": "email,role",
"check": "email.indexOf('test') > -1 && role ==='admin'"
}
}
`

`javascript

const features = require('creature-features')();
// Default behavior
if (features.RuleForEmailFeature(user.email)) {
// do something new
} else {
// do the old thing
}
if (features.RuleForEmailAndRoleFeature({ email: user.email, role: user.account.role })) {
// do something new
} else {
// do the old thing
}
`

#### Weight Based

`json

{
"FeatureOne": true,
"FeatureTwo": true,
"PercentBasedFiftyFifty": {
"range": [50, 50]
},
"PercentBasedOneThird": {
"range": [33, 67]
},
}
`

`javascript

const features = require('creature-features')();
// Roughly 50% of the the time this will be true
if (features.PercentBasedFiftyFifty) {
// do something new
}
// Roughly 33% of the the time this will be true
if (features.PercentBasedOneThird) {
// do something new
}

`

$3

`javascript

const features = require('creature-features')();
const webpack = require('webpack');

const featureFlags = new webpack.DefinePlugin({
FEATURES: features
});

module.exports = {
plugins: [featureFlags],
...

// in a ui file
if (FEATURES.FeatureOne) { }
`

$3

* What are they?
* How are they useful
* More info

$3

`javascript
const creature = require('creature-features');
const prodFeatures = creature('production');
const locationFeatures = creature({location: './my-location/for-features'});
const bothFeatures = creature({location: './my-location/for-features', env: 'staging'});

``