Building REST APIs
Create professional APIs! Learn the principles of REST and build a complete CRUD API with Express.
Create professional APIs! Learn the principles of REST and build a complete CRUD API with Express. This hands-on tutorial focuses on practical implementation of building rest apis concepts.
Building REST APIs
REST (Representational State Transfer) is a set of rules for building APIs. It's how the Frontend (React) talks to the Backend (Node.js).
1. The CRUD Operations 🛠️
Most apps do 4 things with data:
- Create
- Read
- Update
- Delete
In REST, we map these to HTTP Methods:
| Action | HTTP Method | URL Example |
| :--- | :--- | :--- |
| Create | POST | /api/users |
| Read | GET | /api/users (All) or /api/users/1 (One) |
| Update | PUT / PATCH | /api/users/1 |
| Delete | DELETE | /api/users/1 |
2. Building a Todo API 📝
Let's build a full API using an array as a "database".
3. HTTP Status Codes 🚦
Your API should tell the client what happened using status codes.
- 200 OK: Success.
- 201 Created: Success (and something was created).
- 204 No Content: Success (but no data to send back, e.g., after Delete).
- 400 Bad Request: User sent invalid data.
- 401 Unauthorized: User needs to log in.
- 404 Not Found: Resource doesn't exist.
- 500 Internal Server Error: The server crashed.
4. Testing APIs 🧪
You can't test POST/PUT requests easily in the browser address bar. You need tools:
- Postman (Popular desktop app).
- Thunder Client (VS Code extension).
- cURL (Terminal).
AI Mentor
Confused about "REST API design, CRUD operations, HTTP methods, and status codes"? Ask our AI mentor for a simplified explanation.
Quiz
Quiz
Question 1 of 4Which HTTP method is used to create data?
Key Takeaways
✅ REST maps URLs to Resources (Users, Todos).
✅ CRUD maps to HTTP Methods (POST, GET, PUT, DELETE).
✅ Status Codes communicate success or failure.
✅ JSON is the language of APIs.
What's Next?
Our data disappears when the server restarts! We need a database. Next up: Database Integration (MongoDB).
Keep coding! 🚀