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Expo (with prebuild)

Beta release

Beta release

The Sauce Mobile Beta SDK is in beta. The artifact names and the API are final; this documentation can still change. Share feedback with your Sauce Labs representative.

Sauce Mobile Beta for React Native (@saucelabs/mobile-beta-react-native) is a bridge to the Sauce Mobile Beta SDK and is supported for Expo (with prebuild): Expo projects whose native ios and android directories are generated with npx expo prebuild. Integrating the SDK into your app shows you how your app performs on real devices. It shows when and how people use your app and provides any metrics you may need to optimize your user experience and code.

Requirements​

The package contains native iOS and Android code, so it does not run in Expo Go. Your project needs generated ios and android directories before you install it. Generate them with npx expo prebuild, which Expo calls Continuous Native Generation. See the Expo prebuild docs.

The SDK does not install a crash handler. Crash reporting is provided by Backtrace (Sauce Labs Error Reporting), and the two SDKs are designed to run in the same app. Start the SDK with beginWithoutCrashHandler. See Crash Ownership.

Steps​

From your project root, run the following commands:

npx expo prebuild
npm install @saucelabs/mobile-beta-react-native

cd ios
pod install

On Android, the package registers its Maven repositories on every Gradle project, so a standard Expo project needs no repository change. If your android/settings.gradle restricts repositories with RepositoriesMode.FAIL_ON_PROJECT_REPOS, add the Sauce Mobile Beta Maven repository as shown in Android, and re-apply that change (or apply it with a config plugin) after every npx expo prebuild --clean, which regenerates the native directories.

The snippet below uses two values, <sauce-mobile-beta-token> and <server-endpoint>. Both values are in Organization Settings > SDK Settings on your Mobile App Distribution dashboard, under the organization that owns the app. Only Account Owners and Org Admins can open that page. See Organization Settings.

  • SDK App Token: the organization-wide token your app starts sessions with. Regenerating it invalidates the previous token for every build that still carries it.
  • Server Endpoint: the URL the SDK sends session data to, in the form https://<host>/services/. It is specific to your region or private instance, so copy it exactly. If it reads Not configured, contact Sauce Labs support before you ship a build.

Pass the endpoint to setServerEndpoint before beginWithoutCrashHandler. The SDK's built-in default server is no longer in service: an app that skips this call starts no sessions.

Then set the endpoint and start the SDK once per app launch from your root component:

import React, { useEffect } from 'react';
import TestFairy from '@saucelabs/mobile-beta-react-native';

export default function App() {
  useEffect(() => {
    TestFairy.setServerEndpoint('<server-endpoint>');
    TestFairy.beginWithoutCrashHandler('<sauce-mobile-beta-token>');
  }, []);

  return <YourApp />; // your root component tree
}

Notes​

Since all Expo apps are React Native apps behind the scenes, everything on the Integrating the React Native SDK page also applies to Expo: the API notes and the Using With Backtrace summary. If you use Backtrace in the same app, initialize Backtrace first and use @backtrace/react-native 0.2.3 or later (until it is published as stable, npm install @backtrace/react-native@rc), so that the SDK can hand the sauce.correlation_id it generates for every session to Backtrace, as described in Using Sauce Mobile Beta with Backtrace.