upgrade-guide.md

Upgrade from ReactFire v3 to v4

As announced in Discussion 402, ReactFire v4 contains breaking changes. This guide details how to upgrade from v3 to v4.

1. Get the latest version of ReactFire and Firebase

npm i firebase@latest reactfire@latest

# or

yarn add firebase@latest reactfire@latest

2. Initialize product SDKs and register them with ReactFire

You'll need to explicitly initialize each Firebase product you use and pass the initialized SDK into a provider component. For example, if you use the useUser hook in a component, make sure a parent sets up Firebase Auth with the AuthProvider component. Here's a code sample.

If you need to connect to the Local Emulator Suite, check out this code sample.

For times when you need to asynchronously initialize a product, like accessing Firestore data offline or activating Remote Config, you can use hooks like useInitFirestore and useInitRemoteConfig. These hooks replace the preload functions.

3. Update your Firebase code

You'll need to refactor to the modular style of the new Firebase SDK. You can find per-product examples of using ReactFire with the new Firebase SDK here.

Need some samples? Check out the diffs between v3 and v4 for code in the examples directory of the ReactFire repo:

• Authentication
• Firestore
• Realtime Database
• Remote Config
• Storage