User Management API

A RESTful API built in Go for managing users with name and date of birth. Age is calculated dynamically on read operations.

Features

• Full CRUD operations for users
• Dynamic age calculation based on date of birth
• Pagination support for listing users
• Input validation with custom date format checking
• Structured logging with request ID and duration tracking
• Type-safe database access using SQLC
• Containerized with Docker Compose

Tech Stack

• Go with Fiber framework
• PostgreSQL
• SQLC for query generation
• go-playground/validator for validation
• Uber Zap for logging
• pgx PostgreSQL driver

Project Structure

/cmd/server              # Application entry point
/db/migrations           # Database schema migrations
/db/query                # SQLC query definitions
/db/sqlc                 # Generated SQLC code
/internal
  ├── dto                # Request/response DTOs
  ├── handler            # HTTP handlers
  ├── middleware         # Request ID and logging middleware
  ├── models             # Application models
  ├── repository         # Data access layer
  ├── service            # Business logic
  ├── logger             # Zap logger configuration
  └── db                 # Database connection

Setup and Run

Using Docker Compose (Recommended)

# Build and start the services
docker compose up --build

# Subsequent runs
docker compose up

The API will be available at http://localhost:3000
PostgreSQL will be available at localhost:5432

Manual Run (Development)

1. Start PostgreSQL (e.g., via Docker):

docker run --name user-api-postgres \
  -e POSTGRES_PASSWORD=password \
  -e POSTGRES_USER=postgres \
  -e POSTGRES_DB=userdb \
  -p 5432:5432 \
  -v pgdata:/var/lib/postgresql/data \
  -d postgres:15

2. Apply the migration:

docker exec -i user-api-postgres psql -U postgres -d userdb < db/migrations/001_create_users_table.sql

3. Run the application:

go run cmd/server/main.go

API Endpoints

Method	Endpoint	Description
POST	/users	Create a user
GET	/users	List users (with pagination)
GET	/users/:id	Get a user by ID
PUT	/users/:id	Update a user
DELETE	/users/:id	Delete a user

Pagination

GET /users supports:

• limit — number of results per page (default: 20, max: 100)
• offset — number of results to skip (default: 0)

Example: /users?limit=10&offset=20

Example Requests

# Create a user
curl -X POST http://localhost:3000/users \
  -H "Content-Type: application/json" \
  -d '{"name": "Parth", "dob": "2004-05-10"}'

# Get a user by ID
curl http://localhost:3000/users/1

# List users (with pagination)
curl "http://localhost:3000/users?limit=5&offset=0"

# Update a user
curl -X PUT http://localhost:3000/users/1 \
  -H "Content-Type: application/json" \
  -d '{"name": "Parth Kalani", "dob": "2004-08-10"}'

# Delete a user
curl -X DELETE http://localhost:3000/users/1

Observability

• Each request includes an X-Request-ID response header
• Logs contain request method, path, status, duration, and request ID