Mock Service Worker
API mocking at the network level for browser and Node.js
Visit mswjs.io FreeOpen source
Mock Service Worker (MSW) intercepts outgoing requests at the network level and returns mocked responses, using a Service Worker in the browser and request interception in Node.js. The same REST, GraphQL, and WebSocket handlers can be reused across unit tests, end-to-end tests, Storybook, and local development.
Key features
- Network-level request interception
- REST, GraphQL, and WebSocket handlers
- Same mocks in browser and Node.js
- Framework- and client-agnostic
Try it on DevTools Daily
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