@hyphen/openfeature-server-provider NPM

Hyphen Toggle OpenFeature Provider

The Hyphen Toggle OpenFeature Provider is an OpenFeature provider implementation for the Hyphen Toggle platform. It enables feature flag evaluation using the OpenFeature standard.

Getting Started

Installation

Install the provider and the OpenFeature server SDK:

npm install @openfeature/server-sdk @hyphen/openfeature-server-provider

Usage

Example: Basic Setup

To integrate the Hyphen Toggle provider into your application, follow these steps:

Set up the provider: Register the HyphenProvider with OpenFeature using your publicKey and provider options.
Evaluate a feature toggle: Use the client to evaluate a feature flag.

import { OpenFeature } from '@openfeature/server-sdk';
import { HyphenProvider, type HyphenProviderOptions } from '@hyphen/openfeature-server-provider';

const publicKey = "your-public-key-here";

// Example using an alternateId for environment
const options: HyphenProviderOptions = {
  application: 'your-application-name',
  environment: 'production', // Using alternateId format
};

// OR using a project environment ID
// const options: HyphenProviderOptions = {
//   application: 'your-application-name',
//   environment: 'pevr_abc123', // Using project environment ID format
// };

await OpenFeature.setProviderAndWait(new HyphenProvider(publicKey, options));

const client = OpenFeature.getClient();

const flagDetails = await client.getBooleanDetails('feature-flag-key', false);

console.log(flagDetails.value); // true or false

Example: Contextual Evaluation

To evaluate a feature flag with specific user or application context, define and pass an EvaluationContext:

const context: HyphenEvaluationContext = {
  targetingKey: 'user-123',
  // You can specify the environment in the context
  environment: 'production', // or 'pevr_abc123'
  ipAddress: '203.0.113.42',
  customAttributes: {
    subscriptionLevel: 'premium',
    region: 'us-east',
  },
  user: {
    id: 'user-123',
    email: 'user@example.com',
    name: 'John Doe',
    customAttributes: {
      role: 'admin',
    },
  },
};

// Evaluate the toggle with context
const flagDetailsWithContext = await client.getBooleanDetails(toggleKey, defaultValue, context);

console.log(flagDetailsWithContext.value); // true or false

Configuration

Options

Option	Type	Description
`application`	string	The application id or alternate id.
`environment`	string	The environment identifier for the Hyphen project (project environment ID or alternateId).
`horizonUrls`	string[]	An array of Hyphen Horizon URLs to use for fetching feature flags.
`enableToggleUsage`	boolean	Enable or disable the logging of toggle usage (telemetry).
`cache`	object	Configuration for caching feature flag evaluations.

Cache Configuration

The cache option accepts the following properties:

Property	Type	Default	Description
`ttlSeconds`	number	300	Time-to-live in seconds for cached flag evaluations.
`generateCacheKeyFn`	Function	-	Custom function to generate cache keys from evaluation context.

Example with cache configuration:

const options: HyphenProviderOptions = {
  application: 'your-application-name',
  // Using alternateId format:
  environment: 'production',
  // OR using project environment ID format:
  // environment: 'pevr_abc123',
  cache: {
    ttlSeconds: 600, // 10 minutes
    generateCacheKeyFn: (context: HyphenEvaluationContext) => {
      return `${context.targetingKey}-${context.user?.id}`;
    },
  },
};

Context

Provide an EvaluationContext to pass contextual data for feature evaluation.

Context Fields

Field	Type	Description
`targetingKey`	`string`	The key used for caching the evaluation response.
`environment`	`string`	The environment identifier for the Hyphen project (project environment ID or alternateId).
`ipAddress`	`string`	The IP address of the user making the request.
`customAttributes`	`Record<string, any>`	Custom attributes for additional contextual information.
`user`	`object`	An object containing user-specific information for the evaluation.
`user.id`	`string`	The unique identifier of the user.
`user.email`	`string`	The email address of the user.
`user.name`	`string`	The name of the user.
`user.customAttributes`	`Record<string, any>`	Custom attributes specific to the user.

Contributing

We welcome contributions to this project! If you'd like to contribute, please follow the guidelines outlined in CONTRIBUTING.md. Whether it's reporting issues, suggesting new features, or submitting pull requests, your help is greatly appreciated!