FeatBit OpenFeature provider for Node.js SDK

Introduction

This is the OpenFeature provider for the Node.js Server-Side SDK for the 100% open-source feature flags management platform FeatBit.

The FeatBit OpenFeature provider is designed primarily for use in multi-user systems such as web servers and applications. It is not intended for use in desktop and embedded systems applications.

Tracking

After registering and initializing the provider, use the OpenFeature client to track events:

const client = OpenFeature.getClient();
const context = { targetingKey: 'user-123' };

client.track('page-view', context);
client.track('purchase', context, { value: 99.9 });

Tracking uses the same context-to-user mapping as flag evaluations, including targetingKey (or the legacy key), name, and custom user attributes. OpenFeature merges context before passing it to the provider, so a user key set on the client or global context can also be used. The optional value is passed to FeatBit as the numeric metric value; when omitted, the FeatBit SDK defaults it to 1. A value of 0 is preserved. Other tracking event details are ignored because the FeatBit SDK only supports a numeric metric value.

track returns void and does not need to be awaited. Events are delivered by the FeatBit SDK's event processor. Call await OpenFeature.close() at application shutdown to flush pending events and release resources.

Supported Node versions

This version of the FeatBit OpenFeature provider is compatible with Node.js versions 16 and above.

Getting started

Installation

npm install @openfeature/server-sdk
npm install @featbit/node-server-sdk
npm install @featbit/openfeature-provider-node-server

Quick start

import { OpenFeature, ProviderEvents } from '@openfeature/server-sdk';
import { FbProvider } from '@featbit/openfeature-provider-node-server';

const provider = new FbProvider({
    sdkKey: '<your-sdk-key>',
    streamingUri: '<your-streaming-uri>',
    eventsUri: '<your-events-uri>'
});

OpenFeature.setProvider(provider);

// If you need access to the FbClient, then you can use provider.getClient()

// Evaluations before the provider indicates it is ready may get default values with a
// CLIENT_NOT_READY reason.
OpenFeature.addHandler(ProviderEvents.Ready, (eventDetails) => {
    console.log(`Changed ${eventDetails.flagsChanged}`);
});


// The FeatBit provider supports the ProviderEvents.ConfigurationChanged event.
// The provider will emit this event for any flag key that may have changed (each event will contain
// a single key in the `flagsChanged` field).
OpenFeature.addHandler(ProviderEvents.ConfigurationChanged, async (eventDetails) => {
    const client = OpenFeature.getClient();
    const value = await client.getBooleanValue('ff1', false, {targetingKey: 'my-key'});
    console.log({...eventDetails, value});
});

// (async () => {
//     // When the FeatBit provider is closed it will flush the events on the FbClient instance.
//     // This can be useful for short lived processes.
//     await OpenFeature.close();
// })();