Bits of .NET

📐 REST = Architectural Style for APIs

REST APIs are everywhere. Understand REST principles — resources, HTTP methods, status codes.

📝 REST Principles

1. Resources (nouns, not verbs)
   /api/users        (users collection)
   /api/users/1      (single user)
   /api/orders       (orders collection)
   /api/orders/123   (single order)

2. HTTP Methods
   GET    → Read
   POST   → Create
   PUT    → Update (full)
   PATCH  → Update (partial)
   DELETE → Delete

3. Status Codes
   200 OK          → Success
   201 Created     → Created
   400 Bad Request → Invalid request
   401 Unauthorized → Need auth
   404 Not Found   → Resource not found
   500 Server Error → Server error

4. Stateless
   Each request contains all information needed

5. Representation
   JSON, XML, HTML — choose format

🎯 REST API Example

// Get all users
GET /api/users
Response: 200 OK [{ "id": 1, "name": "Alice" }]

// Get single user
GET /api/users/1
Response: 200 OK { "id": 1, "name": "Alice" }

// Create user
POST /api/users
Request: { "name": "Bob", "email": "bob@example.com" }
Response: 201 Created { "id": 2, "name": "Bob" }

// Update user
PUT /api/users/2
Request: { "name": "Robert" }
Response: 200 OK { "id": 2, "name": "Robert" }

// Delete user
DELETE /api/users/2
Response: 204 No Content

💡 Best Practices

• Use nouns for resource names
• Use plural forms (/users, /orders)
• Use nested resources (/users/1/orders)
• Use query parameters for filtering (/users?active=true)
• Version your API (/api/v1/users)