@unleash/proxy-client-react

What is @unleash/proxy-client-react?

@unleash/proxy-client-react is a React client for the Unleash feature management system. It allows developers to easily integrate feature toggles into their React applications, enabling dynamic feature management and experimentation.

What are @unleash/proxy-client-react's main functionalities?

Initialize Unleash Client

This code initializes the Unleash client with the necessary configuration, including the URL of the Unleash API, the client key, and the application name. The `start` method is called to begin fetching feature toggles.

import { UnleashClient } from '@unleash/proxy-client-react';

const client = new UnleashClient({
  url: 'https://app.unleash-hosted.com/demo/api/',
  clientKey: 'proxy-client-key',
  appName: 'my-react-app'
});

client.start();

Use Feature Toggles in Components

This code demonstrates how to use the `useFlag` hook to check the status of a feature toggle within a React component. Depending on whether the feature toggle is enabled or disabled, different content is rendered.

import { useFlag } from '@unleash/proxy-client-react';

const MyComponent = () => {
  const isEnabled = useFlag('my-feature-toggle');

  return (
    <div>
      {isEnabled ? <p>Feature is enabled</p> : <p>Feature is disabled</p>}
    </div>
  );
};

Custom Context Provider

This code shows how to wrap your application with the `UnleashProvider` to provide the Unleash client configuration context to all components within the application. This makes it easier to use feature toggles throughout the app.

import { UnleashProvider } from '@unleash/proxy-client-react';

const App = () => (
  <UnleashProvider
    config={{
      url: 'https://app.unleash-hosted.com/demo/api/',
      clientKey: 'proxy-client-key',
      appName: 'my-react-app'
    }}
  >
    <MyComponent />
  </UnleashProvider>
);

Other packages similar to @unleash/proxy-client-react

react-feature-toggles

react-feature-toggles is a lightweight library for managing feature toggles in React applications. It provides a simple API for defining and using feature toggles, but it does not offer the same level of integration with a feature management system like Unleash.

launchdarkly-react-client-sdk

launchdarkly-react-client-sdk is the official React SDK for LaunchDarkly, a feature management platform. It offers similar functionality to @unleash/proxy-client-react, including feature flag evaluation and context management, but it is tied to the LaunchDarkly service.

react-ab-test

react-ab-test is a library for A/B testing in React applications. It allows developers to define experiments and variants, and track user interactions. While it focuses on A/B testing rather than feature toggles, it provides similar capabilities for experimentation.

README

DISCLAIMER:

This library is meant to be used with the unleash-proxy. The proxy application layer will sit between your unleash instance and your client applications, and provides performance and security benefits. DO NOT TRY to connect this library directly to the unleash instance, as the datasets follow different formats because the proxy only returns evaluated toggle information.

Installation

npm install @unleash/proxy-client-react
// or
yarn add @unleash/proxy-client-react

Import the provider like this in your entrypoint file (typically index.js/ts):

import FlagProvider from '@unleash/proxy-client-react';

const config = {
  url: 'https://HOSTNAME/proxy',
  clientKey: 'PROXYKEY',
  refreshInterval: 15,
  appName: 'your-app-name',
  environment: 'dev',
};

ReactDOM.render(
  <React.StrictMode>
    <FlagProvider config={config}>
      <App />
    </FlagProvider>
  </React.StrictMode>,
  document.getElementById('root')
);

To check if a feature is enabled:

import { useFlag } from '@unleash/proxy-client-react';

const TestComponent = () => {
  const enabled = useFlag('travel.landing');

  if (enabled) {
    return <SomeComponent />
  }
  return <AnotherComponent />
};

export default TestComponent;

To check variants:

import { useVariant } from '@unleash/proxy-client-react';

const TestComponent = () => {
  const variant = useVariant('travel.landing');

  if (variant.enabled && variant.name === "SomeComponent") {
    return <SomeComponent />
  } else if (variant.enabled && variant.name === "AnotherComponent") {
    return <AnotherComponent />
  }
  return <DefaultComponent />
};

export default TestComponent;

Defer rendering until flags fetched

useFlagsStatus retrieves the ready state and error events. Follow the following steps in order to delay rendering until the flags have been fetched.

import { useFlagsStatus } from '@unleash/proxy-client-react'

const MyApp = () => {
  const { flagsReady, flagsError } = useFlagsStatus();

  if (!flagsReady) {
    return <Loading />
  }
  return <MyComponent error={flagsError}/>
}

Updating context

Follow the following steps in order to update the unleash context:

import { useUnleashContext, useFlag } from '@unleash/proxy-client-react'

const MyComponent = ({ userId }) => {
  const variant = useFlag("my-toggle");
  const updateContext = useUnleashContext();

  useEffect(() => {
    // context is updated with userId
    updateContext({ userId })
  }, [])
}