Hi! My name is [Artem](https://kettanaito.com), and in this course I will teach you how to mock WebSocket APIs with [Mock Service Worker](https://mswjs.io). You and I are going to build a chat application mock-first, and you will learn how to intercept WebSocket connections, handle client and server events, and also test the code that relies on WebSocket in Vitest and Playwright. Let's go!

Introduction to Mocking WebSocket APIs with Mock Service Worker

Install Mock Service Worker (MSW)

Set up Mock Service Worker in the browser, (1) generate a worker script via the `npx msw init` command; (2) create `mocks/borwser.ts` and use `setupWorker()` to create a worker instance; (3) defer your application's rendering in `entry.client.tsx` by introducing an `enableMocking()` function that calls `await worker.start()`.

## Resources

- [Browser integration of MSW](https://mswjs.io/docs/integrations/browser)
- [`setupWorker()`](https://mswjs.io/docs/api/setup-worker)
- [ `worker.start()`](https://mswjs.io/docs/api/setup-worker/start)


Mocking WebSocket APIs with Mock Service Worker

Zac Jones

Course Content