OpenFeature provider

The @westyx-nexus/openfeature-provider-react package bridges the Nexus React SDK into the OpenFeature Web SDK. It wraps an existing NexusClient and emits ConfigurationChanged on every cache update so OpenFeature clients re-evaluate flags automatically.

Installation

npm install @westyx-nexus/sdk-react @westyx-nexus/openfeature-provider-react @openfeature/react-sdk

Configure the npm registry for the Westyx Nexus scope - see Installation.

Quick start

import { OpenFeature, useBooleanFlagValue } from '@openfeature/react-sdk';
import { NexusClient } from '@westyx-nexus/sdk-react';
import { createOpenFeatureProvider } from '@westyx-nexus/openfeature-provider-react';

// Bootstrap - call once before rendering your React tree.
const client = await NexusClient.create({
  baseUrl: 'https://blue-ocean-a5rx7.westyx.dev',
  apiKey:  'wxp_...',
});
await OpenFeature.setProviderAndWait(createOpenFeatureProvider(client));

// In a component - standard OpenFeature hooks.
function Checkout() {
  const showBanner = useBooleanFlagValue('banner.enabled', false);
  return (
    <div>
      {showBanner && <Banner />}
      <CheckoutForm />
    </div>
  );
}

Evaluation mapping

OpenFeature method	Nexus source	Error codes
`resolveBooleanEvaluation`	`client.getFlag(key, default)`	None - `getFlag` always returns a value
`resolveStringEvaluation`	`client.getConfig(key)`	`FLAG_NOT_FOUND` if absent; `TYPE_MISMATCH` if not a string
`resolveNumberEvaluation`	`client.getConfig(key)`	`FLAG_NOT_FOUND` if absent; `TYPE_MISMATCH` if not coercible to a number
`resolveObjectEvaluation`	`client.getConfig(key)`	`FLAG_NOT_FOUND` if absent; `TYPE_MISMATCH` if not an object or array

All evaluations use the STATIC resolution reason. The provider does not perform per-user targeting - use client.evaluateAB() directly for that.

Live updates

The provider subscribes to the Nexus client on initialize(). Each time the client’s cache refreshes - via SSE push or TTL poll - the provider emits ProviderEvents.ConfigurationChanged. OpenFeature’s React bindings pick this up and trigger re-renders in components that consume the changed flags.

API reference

`NexusReactProvider`

class NexusReactProvider implements Provider {
  constructor(client: NexusClient);
  readonly runsOn: 'client';
  initialize(context?: EvaluationContext): Promise<void>;
  onClose(): Promise<void>;
  resolveBooleanEvaluation(flagKey: string, defaultValue: boolean, ...): ResolutionDetails<boolean>;
  resolveStringEvaluation(flagKey: string, defaultValue: string, ...): ResolutionDetails<string>;
  resolveNumberEvaluation(flagKey: string, defaultValue: number, ...): ResolutionDetails<number>;
  resolveObjectEvaluation<T extends JsonValue>(flagKey: string, defaultValue: T, ...): ResolutionDetails<T>;
}

`createOpenFeatureProvider`

function createOpenFeatureProvider(client: NexusClient): NexusReactProvider;

Convenience factory equivalent to new NexusReactProvider(client).

Browser SDKs must use a wxp_... (public) key. Never embed secret keys (wxs_...) in browser code.

Overview

Backend SDKs

Browser SDKs