API Mock Server

Create configurable mock API responses (path, method, status, JSON body, optional delay) stored in Workers KV. Any matching request to /mock/:slug returns the configured response.

Features

• POST /configs - create a mock and receive a slug
• GET /configs - list all mocks
• GET /mock/:slug - serve the configured response
• DELETE /configs/:slug - remove a mock

API Reference

POST /configs

Create a mock endpoint configuration.

path string (required) - Mock path (must start with /).

method string (required) - HTTP method.

status number (required) - Response status (100–599).

body object (required) - JSON response body.

delayMs number (optional) - Artificial delay (0–30000 ms).

GET /mock/:slug

Serve the mock when the request method matches the stored config.

DELETE /configs/:slug

Delete a mock by slug.

Error Codes

• 400 - INVALID_BODY, validation errors
• 404 - NOT_FOUND

Use Cases

• Stub third-party APIs during frontend development
• Demo API integrations without standing up a full backend
• Test client retry and timeout behavior with configurable delays

Limitations

• Requires a KV namespace binding
• No authentication on config endpoints
• Mocks are global to the namespace; not multi-tenant

Deployment

Local Development

cd apps/experiments/api-mock-server
npm install
npm run dev

Configuration

Create a KV namespace and set its id in wrangler.json under MOCKS.

Cloudflare Features Used

• Workers
• Workers KV