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JavaScript (Browser)

Client-side JavaScript SDK for evaluating Toggle feature flags in web browsers.

The @hyphen/browser-sdk is Hyphen's native client-side JavaScript SDK for web browsers. It's optimized for evaluating Toggle feature flags in the browser with a minimal bundle size.

Table of Contents

Installation

npm install @hyphen/browser-sdk

Authentication

The SDK authenticates with your project public key (it starts with public_) and your application id. See Get a Project's Public Key for where to find these in the Hyphen dashboard.

Initialization

Provide a defaultContext describing the current user so flags can be targeted correctly:

import { Toggle } from '@hyphen/browser-sdk';

const toggle = new Toggle({
  publicApiKey: 'public_your-api-key-here',
  applicationId: 'your-app-id',
  environment: 'production',
  defaultContext: {
    targetingKey: 'user-123',
    user: {
      id: 'user-123',
      email: '[email protected]',
      name: 'John Doe',
    },
  },
});

Usage

const isEnabled = await toggle.getBoolean('feature-flag', false);

if (isEnabled) {
  console.log('Feature is enabled!');
}

See also