@chengyixu/mockapi

Instantly spin up a mock REST API from a JSON file. Zero-config CRUD endpoints with hot reload, request recording, and OpenAPI spec generation.

Install

npm install -g @chengyixu/mockapi

Quick Start

Create a db.json file:

{
  "users": [
    { "id": 1, "name": "Alice", "email": "[email protected]" },
    { "id": 2, "name": "Bob", "email": "[email protected]" }
  ],
  "posts": [
    { "id": 1, "title": "Hello World", "userId": 1 }
  ]
}

Start the server:

mockapi serve db.json

You now have a full REST API:

GET    /users        # List all users
GET    /users/1      # Get user by ID
POST   /users        # Create a new user
PUT    /users/1      # Update a user
DELETE /users/1      # Delete a user

Features

• Auto CRUD - Endpoints auto-generated from JSON keys
• Hot Reload - Server reloads when the JSON file changes
• Query Filtering - GET /users?name=Alice
• Sorting - GET /users?_sort=name&_order=desc
• Pagination - GET /users?_page=1&_limit=10
• Custom Routes - Define custom endpoints via config
• Artificial Latency - Simulate slow APIs with --delay
• CORS Enabled - Works with any frontend out of the box
• Colored Logging - Method-colored request logs
• Record Mode - Proxy a real API and save responses
• OpenAPI Spec - Auto-generate OpenAPI 3.0 from your data
• Zero External Deps - Server uses native Node.js http module

Commands

mockapi serve <file>

Start a mock REST API server.

mockapi serve db.json
mockapi serve db.json --port 8080
mockapi serve db.json --delay 500        # 500ms latency
mockapi serve db.json --routes routes.json
mockapi serve db.json --no-watch         # Disable hot reload

Options:

• -p, --port <number> - Port (default: 3000)
• -H, --host <string> - Host (default: localhost)
• -d, --delay <ms> - Artificial latency in ms (default: 0)
• -r, --routes <file> - Custom routes JSON file
• --no-watch - Disable hot reload

mockapi record <url>

Proxy requests to a real API and record responses.

mockapi record https://jsonplaceholder.typicode.com
mockapi record https://api.example.com -o api-data.json -p 8080

Options:

• -p, --port <number> - Local proxy port (default: 3000)
• -H, --host <string> - Host (default: localhost)
• -o, --output <file> - Output file (default: recorded.json)

mockapi openapi <file>

Generate an OpenAPI 3.0 specification from your data file.

mockapi openapi db.json                  # Print to stdout
mockapi openapi db.json -o spec.json     # Write to file

Custom Routes

Create a routes.json:

[
  {
    "method": "GET",
    "path": "/health",
    "status": 200,
    "body": { "status": "ok" }
  },
  {
    "method": "POST",
    "path": "/login",
    "status": 200,
    "body": { "token": "mock-jwt-token" }
  }
]

mockapi serve db.json --routes routes.json

License

MIT