Mock Service Worker

Mock Service Worker

Mock Service Worker (MSW) is an open-source library for mocking REST, GraphQL, WebSocket, and Server-Sent Events APIs at the network level. It provides setupWorker for browser environments and setupServer for Node.js, with handlers (http, graphql, ws, sse) that allow developers to declare mocked responses without modifying application code.

GitHub

Documentation

📖
Documentation
https://mswjs.io/docs/
📖
GettingStarted
https://mswjs.io/docs/quick-start

Other Resources

🔗
HTTP Handler
https://mswjs.io/docs/network-behavior/rest
🔗
GraphQL Handler
https://mswjs.io/docs/network-behavior/graphql
🔗
WebSocket Handler
https://mswjs.io/docs/network-behavior/websocket
🔗
GitHub
https://github.com/mswjs/msw
🔗
Examples
https://github.com/mswjs/examples
🔗
NPM
https://www.npmjs.com/package/msw
🔗
License
https://github.com/mswjs/msw/blob/main/LICENSE.md
🔗
GraphQL
https://raw.githubusercontent.com/api-evangelist/mock-service-worker/refs/heads/main/graphql/mock-service-worker-graphql.md
🔗
APIsJSON
https://raw.githubusercontent.com/api-evangelist/mock-service-worker/refs/heads/main/apis.yml

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API entry from apis.yml

apis.yml Raw ↑ 
aid: mock-service-worker:msw
name: Mock Service Worker
description: Mock Service Worker (MSW) is an open-source library for mocking REST, GraphQL, WebSocket,
  and Server-Sent Events APIs at the network level. It provides setupWorker for browser environments and
  setupServer for Node.js, with handlers (http, graphql, ws, sse) that allow developers to declare mocked
  responses without modifying application code.
image: https://mswjs.io/static/logos/msw-logo.svg
humanURL: https://mswjs.io/
baseURL: https://mswjs.io/
tags:
- API Mocking
- GraphQL
- HTTP
- Mocking
- Service Worker
- Testing
- WebSocket
properties:
- type: Documentation
  url: https://mswjs.io/docs/
- type: GettingStarted
  url: https://mswjs.io/docs/quick-start
- type: HTTP Handler
  url: https://mswjs.io/docs/network-behavior/rest
- type: GraphQL Handler
  url: https://mswjs.io/docs/network-behavior/graphql
- type: WebSocket Handler
  url: https://mswjs.io/docs/network-behavior/websocket
- type: GitHub
  url: https://github.com/mswjs/msw
- type: Examples
  url: https://github.com/mswjs/examples
- type: NPM
  url: https://www.npmjs.com/package/msw
- type: License
  url: https://github.com/mswjs/msw/blob/main/LICENSE.md
- url: graphql/mock-service-worker-graphql.md
  type: GraphQL
contact:
- FN: MSW Maintainers
  url: https://github.com/mswjs/msw