FeatureFlagClient

Allows you to use feature flags in your code, works with any JSON feature flag service.

Features:

• Stops you from littering your code with if statements.
• Extremely light-weight ( < 60 lines of code, 1 dependency ).
• Feature flag service agnostic.
• Serverless runtime support (NodeJS 6.10 compliant, will work on AWS Lambda)

Awesome API means you don't use if statements in your code:

featureflagclient.when( "newFeature" )
	.is( true, () => {
		// do the new stuff
	});

But will let you use if statements if you want to:

if ( featureflagclient.get( "newFeature" ) ) {
	// do some stuff
}

Created by featureflag.tech.

Install

npm install featureflagclient --save

Usage

const Featureflagclient = require( "featureflagclient-node" );

const featureflagclient = new Featureflagclient( "http://featureflag.tech/node/exampleflag.json" );

featureflagclient.getSourceFile().then( () => {

	featureflagclient.when( "newFeature" )
		.is( true, () => {
			// do the new stuff
		})
		.is( false, () => {
			// do the old stuff
		})
		.else( () => {
			// do default stuff
		});

	if ( f2t.get( "newFeature" ) ) {
		// do some stuff
	}

}).catch( console.log );

if ( featureflagclient.get( "newFeature" ) ) {
	// do some stuff
}

A great way to use feature flags is to use the values from your flag source but override them in specific contexts. For example with a web application, you can have a feature disabled by default in your live production, but then override the value using a cookie or parameter in the request.

For example:

const Featureflagclient = require( "featureflagclient-node" );

const featureflagclient = 
	new Featureflagclient(
		"http://featureflag.tech/node/exampleflag.json",
		{
			"falseBoolean": req.param( "falseBooleanOverride" ) || null
		}
	);

featureflagclient.getSourceFile().then( () => {

	featureflagclient.get( "falseBoolean" ) // returns true

});

Develop

Check the project out:

git clone git@github.com:tmaslen/featureflagclient-node.git

Install deps:

npm install

Run the unit tests:

npm test

Run the integration tests:

node test/integrationTests.js