Building a RESTful API with Go and Clean Architecture

A RESTful API for user management built with Go (Golang) using Clean Architecture and MySQL as the database. This project focuses on writing clean, modular, and maintainable code without relying on heavyweight frameworks.

Tech Stack

| Technology | Description | |---|---| | Go | Backend language | | net/http | HTTP server (native) | | MySQL | Database | | godotenv | Load environment variables | | bcrypt | Password hashing |

Project Structure

restfull-api-go/
├── cmd/api/main.go                          # Entry point
├── config/config.go                         # Configuration
├── internal/
│   ├── domain/user.go                       # Entity & interface
│   ├── repository/user_repository.go        # Database layer
│   ├── usecase/user_usecase.go              # Business logic
│   └── delivery/http/
│       ├── handler/user_handler.go          # HTTP handlers
│       ├── middleware/logger.go             # Logger middleware
│       └── router/
│           ├── router.go                    # Main router
│           └── user_router.go              # User routes
├── pkg/
│   ├── database/mysql.go                    # DB connection
│   └── helper/response.go                  # Response helper
├── .env.example                             # Environment template
├── Makefile                                 # Build scripts
└── go.mod

Architecture

This project uses Clean Architecture with the following request/response flow:

Request → Router → Middleware → Handler → Usecase → Repository → Database
                                                                      ↓
Response ← Router ← Middleware ← Handler ← Usecase ← Repository ← Database

| Layer | Package | Responsibility | |---|---|---| | Domain | internal/domain | Entity & interface contract | | Repository | internal/repository | Database operations | | Usecase | internal/usecase | Business logic | | Handler | internal/delivery/http/handler | HTTP request/response | | Middleware | internal/delivery/http/middleware | Cross-cutting concerns | | Router | internal/delivery/http/router | Route definitions |

Quick Start

1. Clone & Install

git clone https://github.com/VoinzzZ/restfull-api-go.git
cd restfull-api-go
go mod tidy

2. Setup Environment

cp .env.example .env

Fill in your .env:

DB_HOST=localhost
DB_PORT=3306
DB_USER=root
DB_PASSWORD=your_password
DB_NAME=go_api_db
PORT=8080

3. Setup Database

CREATE DATABASE go_api_db;

USE go_api_db;

CREATE TABLE users (
    id INT AUTO_INCREMENT PRIMARY KEY,
    name VARCHAR(100) NOT NULL,
    email VARCHAR(100) NOT NULL UNIQUE,
    password VARCHAR(255) NOT NULL,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP
);

4. Run the Server

make run

Output:

2026/02/19 01:12:00 Database connected successfully
2026/02/19 01:12:00 Server starting on http://localhost:8080

API Endpoints

Base URL: http://localhost:8080

| Method | Endpoint | Description | |---|---|---| | POST | /api/v1/users | Create a new user | | GET | /api/v1/users | Get all users | | GET | /api/v1/users/{id} | Get user by ID | | PUT | /api/v1/users/{id} | Update user | | DELETE | /api/v1/users/{id} | Delete user |

API Reference

Create User

POST /api/v1/users

{
  "name": "John Doe",
  "email": "john@example.com",
  "password": "password123"
}

Response 201 Created:

{
  "status": 201,
  "message": "User created successfully",
  "data": {
    "id": 1,
    "name": "John Doe",
    "email": "john@example.com",
    "created_at": "2026-02-19T01:12:00Z",
    "updated_at": "2026-02-19T01:12:00Z"
  }
}

Get All Users

GET /api/v1/users

Response 200 OK:

{
  "status": 200,
  "message": "Users retrieved successfully",
  "data": [
    {
      "id": 1,
      "name": "John Doe",
      "email": "john@example.com",
      "created_at": "2026-02-19T01:12:00Z",
      "updated_at": "2026-02-19T01:12:00Z"
    }
  ]
}

Get User by ID

GET /api/v1/users/{id}

Response 200 OK:

{
  "status": 200,
  "message": "User found",
  "data": {
    "id": 1,
    "name": "John Doe",
    "email": "john@example.com"
  }
}

Response 404 Not Found:

{
  "status": 404,
  "message": "user not found"
}

Update User

PUT /api/v1/users/{id}

{
  "name": "John Updated",
  "email": "john.new@example.com"
}

Delete User

DELETE /api/v1/users/{id}

Response 200 OK:

{
  "status": 200,
  "message": "User deleted successfully"
}

Testing with cURL

# Create user
curl -X POST http://localhost:8080/api/v1/users \
  -H "Content-Type: application/json" \
  -d '{"name":"John Doe","email":"john@example.com","password":"password123"}'

# Get all users
curl http://localhost:8080/api/v1/users

# Get user by ID
curl http://localhost:8080/api/v1/users/1

# Update user
curl -X PUT http://localhost:8080/api/v1/users/1 \
  -H "Content-Type: application/json" \
  -d '{"name":"John Updated","email":"john.new@example.com"}'

# Delete user
curl -X DELETE http://localhost:8080/api/v1/users/1

Makefile Commands

make run    # Run the server (development)
make build  # Compile to binary
make start  # Run the compiled binary
make clean  # Remove binary

Source code available on GitHub.