Amar Pathagar Backend

A trust-based book sharing platform backend built with Clean Architecture and Domain-Driven Design.

Architecture

This backend follows eventrizo-backend's clean architecture pattern with:

• Domain Layer - Pure business entities with no dependencies
• Service Layer - Business logic with port interfaces
• Repository Layer - Data access implementations
• REST Layer - HTTP delivery (handlers, middleware, responses)
• Infrastructure Layer - External dependencies (database, logger)

Tech Stack

Category	Technology
Language	Go 1.23
Framework	Gin
Database	PostgreSQL 15
DB Driver	lib/pq
Logging	Zap (structured)
Auth	JWT
Hot Reload	Air
Container	Docker

Quick Start

# 1. Copy environment file
cp .env.example .env

# 2. (Optional) Edit .env to set admin credentials
# ADMIN_USERNAME=admin
# ADMIN_EMAIL=admin@amarpathagar.com
# ADMIN_PASSWORD=admin123
# ADMIN_FULL_NAME=System Administrator

# 3. Start development (with hot reload)
make dev

# 4. Run migrations
make migrate-up

# 5. Create admin user
make seed

# 6. Test the API
curl http://localhost:8080/health

# 7. View API Documentation
open http://localhost:8080/docs

Or use the quick-start command:

make quick-start  # Runs dev + migrate + seed + logs

Default Admin Credentials

After running make seed, you can login with:

• Username: admin (or value from ADMIN_USERNAME in .env)
• Email: admin@amarpathagar.com (or value from ADMIN_EMAIL in .env)
• Password: admin123 (or value from ADMIN_PASSWORD in .env)

⚠️ IMPORTANT: Change the admin password immediately after first login in production!

API Documentation

The API documentation is automatically served at /docs when the application starts.

• Swagger UI: http://localhost:8080/docs
• OpenAPI Spec: http://localhost:8080/docs/swagger.yaml

The documentation includes:

• All API endpoints with request/response examples
• Authentication requirements
• Request/response schemas
• Interactive API testing interface

You can also view the raw OpenAPI 3.0 specification in docs/swagger.yaml.

Project Structure

backend/
├── cmd/
│   ├── main.go              # Bootstrap
│   └── server.go            # Dependency injection
├── internal/
│   ├── domain/              # Domain entities (8 files)
│   │   ├── error.go
│   │   ├── user.go
│   │   ├── book.go
│   │   ├── idea.go
│   │   ├── review.go
│   │   ├── donation.go
│   │   ├── bookmark.go
│   │   └── notification.go
│   ├── auth/                # Auth service
│   ├── book/                # Book service
│   ├── user/                # User service
│   ├── idea/                # Idea service
│   ├── review/              # Review service
│   ├── donation/            # Donation service
│   ├── bookmark/            # Bookmark service
│   ├── successscore/        # Success score service
│   ├── notification/        # Notification service
│   ├── repository/          # Data access layer
│   ├── rest/
│   │   ├── handler/         # HTTP handlers
│   │   ├── middleware/      # Auth, CORS, Logger
│   │   └── response/        # Response helpers
│   ├── infrastructure/
│   │   ├── db/postgres/     # Database connection
│   │   └── logger/          # Zap logger
│   └── config/              # Configuration
├── .air.toml                # Hot reload config
├── docker-compose.yml       # Production
├── docker-compose.dev.yml   # Development
├── Dockerfile               # Multi-stage build
└── Makefile                 # Commands

API Endpoints

Authentication

• POST /api/v1/auth/register - Register user
• POST /api/v1/auth/login - Login user
• GET /api/v1/me - Get current user (protected)

Books

• GET /api/v1/books - List books
• GET /api/v1/books/:id - Get book
• POST /api/v1/books - Create book (protected)
• PATCH /api/v1/books/:id - Update book (protected)
• DELETE /api/v1/books/:id - Delete book (protected)

Users

• GET /api/v1/users/:id/profile - Get user profile
• GET /api/v1/leaderboard - Get leaderboard

Reading Ideas

• POST /api/v1/ideas - Create idea (protected)
• GET /api/v1/books/:bookId/ideas - Get ideas for book
• POST /api/v1/ideas/:id/vote - Vote on idea (protected)

Reviews

• POST /api/v1/reviews - Create review (protected)
• GET /api/v1/users/:id/reviews - Get user reviews

Donations

• POST /api/v1/donations - Create donation (protected)
• GET /api/v1/donations - List donations

Bookmarks

• POST /api/v1/bookmarks - Create bookmark (protected)
• DELETE /api/v1/bookmarks/:bookId - Delete bookmark (protected)
• GET /api/v1/bookmarks - Get user bookmarks (protected)

Development Commands

make dev          # Start with hot reload
make up           # Start production mode
make down         # Stop containers
make restart      # Restart backend
make logs         # View logs
make db-shell     # Access database
make migrate-up   # Run migrations
make seed         # Create admin user
make test         # Run tests
make lint         # Run linter
make build        # Build binary
make clean        # Clean up
make help         # Show all commands

Environment Variables

See .env.example for all configuration options:

# Database
DB_HOST=postgres
DB_PORT=5432
DB_USER=library_user
DB_PASSWORD=library_pass
DB_NAME=online_library

# Server
PORT=8080
GIN_MODE=debug

# JWT
JWT_SECRET=your-secret-key-change-in-production

Success Score System

Users earn/lose points based on actions:

Action	Points
Return book on time	+10
Return book late	-15
Positive review (4-5 stars)	+5
Negative review (<3 stars)	-10
Post reading idea	+3
Idea upvoted	+1
Idea downvoted	-1
Lost book	-50
Donate book	+20
Money donation	+10

Architecture Benefits

✅ Clean Architecture - Clear separation of concerns
✅ Testability - Easy to mock via port interfaces
✅ Maintainability - Domain logic isolated
✅ Scalability - Easy to add new domains
✅ Type Safety - UUID types, domain entities
✅ Structured Logging - Production-ready with Zap
✅ Graceful Shutdown - Context-based cancellation

Testing

# Run tests
make test

# Run with coverage
make test-cover

# Run specific package
go test ./internal/auth/...

Deployment

Docker Production

# Build and start
make up

# Check status
docker ps

# View logs
docker logs amar-pathagar-backend

Standalone Binary

# Build
make build-binary

# Run
./amar-pathagar-api

Contributing

1. Fork the repository
2. Create feature branch (git checkout -b feature/amazing-feature)
3. Commit changes (git commit -m 'Add amazing feature')
4. Push to branch (git push origin feature/amazing-feature)
5. Open Pull Request

License

MIT License

---

Built with Clean Architecture principles 🏗️