How to Update SWR Library in React

This article provides a straightforward guide on how to update the SWR (Stale-While-Revalidate) library in your React applications. You will learn the terminal commands required to upgrade the package, how to verify the installation, and key considerations for handling potential breaking changes between major SWR versions.

Step 1: Update the Package Using Your Package Manager

To update SWR to the latest version, run the appropriate command in your project’s root directory depending on the package manager you use:

Using npm:

npm install swr@latest

Using Yarn:

yarn add swr@latest

Using pnpm:

pnpm add swr@latest

If you need to update to a specific version instead of the latest, replace @latest with the desired version number (for example, swr@2.2.0).

Step 2: Verify the Update

After the installation process completes, confirm that the library has updated successfully by checking your project’s package.json file. Look for the "swr" entry under dependencies:

"dependencies": {
  "react": "^18.0.0",
  "swr": "^2.2.5" 
}

You can also run the following command in your terminal to verify the currently installed version of SWR in your node_modules:

npm list swr

Step 3: Handle Major Version Migrations

If you are upgrading between major versions (for example, from SWR 1.x to SWR 2.x), you may need to update your codebase to accommodate breaking changes.

Key Changes in SWR 2.x to Keep in Mind:

Mutate Arguments: The global mutate function and the bound mutate returned by useSWR accept different argument structures. Ensure your custom mutator functions align with the new signature.
SWRConfig Provider: Some default configurations, such as suspense mode behavior and error handling retries, have been refined. If you use a global <SWRConfig> provider, review your configuration options.
New Features: SWR 2.x introduced new APIs like useSWRMutation for handling manual mutations (like POST/PUT requests). You can refactor old useSWR hacks into this new hook for cleaner code.

Step 4: Test Your Application

Run your development server to ensure there are no compilation errors or runtime warnings:

npm run dev

Test critical paths in your application that rely on data fetching to ensure that caching, revalidation, and loading states still function as expected.