REST API Design

Design RESTful APIs with proper conventions and developer experience.

Resource Naming

# Good - nouns, plural, hierarchical
GET    /api/users
GET    /api/users/123
GET    /api/users/123/orders
POST   /api/users
PATCH  /api/users/123
DELETE /api/users/123

# Bad - verbs, actions in URL
GET    /api/getUsers
POST   /api/createUser
POST   /api/users/123/delete

HTTP Methods

Method	Purpose	Idempotent
GET	Read resource	Yes
POST	Create resource	No
PUT	Replace resource	Yes
PATCH	Partial update	Yes
DELETE	Remove resource	Yes

Status Codes

Code	Meaning	Use For
200	OK	Successful GET, PATCH
201	Created	Successful POST
204	No Content	Successful DELETE
400	Bad Request	Validation errors
401	Unauthorized	Missing auth
403	Forbidden	Insufficient permissions
404	Not Found	Resource doesn't exist
429	Too Many Requests	Rate limited

Response Format

{
  "data": {
    "id": "123",
    "type": "user",
    "attributes": {
      "name": "John",
      "email": "john@example.com"
    }
  },
  "meta": {
    "requestId": "req_abc123"
  }
}

Collection Response

{
  "data": [...],
  "pagination": {
    "page": 1,
    "limit": 20,
    "total": 150,
    "totalPages": 8
  },
  "links": {
    "self": "/api/users?page=1",
    "next": "/api/users?page=2"
  }
}

Query Parameters

GET /api/products?category=electronics    # Filtering
GET /api/products?sort=-price,name        # Sorting
GET /api/products?page=2&limit=20         # Pagination
GET /api/products?fields=id,name,price    # Field selection

Best Practices

• Use nouns for resources, not verbs
• Version API via URL path (/api/v1/)
• Return appropriate status codes
• Include pagination for collections
• Document with OpenAPI/Swagger