🌐 Realtime Translator API

A high-performance, production-ready REST API built with NestJS. This project provides a robust foundation with enterprise-grade features including security hardening, rate limiting, structured logging, and comprehensive API documentation.

🚀 Features

Core Capabilities

• ⚡ High Performance - Optimized for low-latency responses with response compression
• 🔒 Security First - Helmet.js integration with API-focused security headers
• 📊 Structured Logging - Pino.js for high-performance JSON logging
• 📖 API Documentation - Auto-generated Swagger/OpenAPI documentation
• 🎯 API Versioning - URI-based versioning (/v1, /v2, etc.)
• ✅ Request Validation - Class-validator powered DTO validation
• 🛡️ Rate Limiting - Multi-tier throttling protection (short/medium/long)

Developer Experience

• 🐳 Docker Ready - Containerized with optimized multi-stage builds
• 🔄 Hot Reload - Fast development iteration with watch mode
• 📝 Conventional Commits - Enforced via Commitlint
• 🎨 Code Quality - ESLint, Prettier, and CSpell integration
• 🧪 Testing Ready - Jest configuration for unit and e2e tests
• 📦 Path Aliases - Clean imports with @app/* aliases

Production Features

• 🔄 Graceful Shutdown - Proper container lifecycle management
• 📈 Auto Versioning - Semantic versioning based on commits
• 🔧 Environment Config - Flexible configuration via environment variables
• 🚦 HSTS Support - Strict Transport Security in production

📋 Prerequisites

• Node.js >= 24
• npm or yarn
• Docker & Docker Compose (optional)

🛠️ Installation

# Clone the repository
git clone <repository-url>
cd realtime-translator-api

# Install dependencies
npm install

# Copy environment variables
cp .env.sample .env

⚙️ Configuration

Configure the application via environment variables:

Variable	Description	Default
APP_NAME	Application name	nestjs-api
APP_ENV	Environment (development, production)	development
HTTP_PORT	Server port	3003
HTTP_VERSION	API version number	1
HTTP_VERSIONING_ENABLE	Enable API versioning	false

🚀 Running the Application

Development Mode

# Start with hot-reload
npm run start:dev

# Start with debug mode
npm run start:debug

Using Docker

# Build and run with Docker Compose
docker compose up --build

# Run in detached mode
docker compose up -d --build

Production

# Build the application
npm run build:prod

# Start production server
npm run start:prod

📖 API Documentation

Once the application is running, access the Swagger documentation at:

http://localhost:3003/docs

🧪 Testing

# Run unit tests
npm run test

# Run tests in watch mode
npm run test:watch

# Run e2e tests
npm run test:e2e

📁 Project Structure

src/
├── config/           # Configuration modules
│   ├── app.config.ts # Application settings
│   └── doc.config.ts # Swagger documentation config
├── helpers/          # Utility functions and interceptors
├── main.module.ts    # Root application module
├── main.ts           # Application entry point
└── swagger.ts        # Swagger setup

🔒 Security Features

This API implements several security best practices:

• Helmet.js - Sets various HTTP headers for security
• HSTS - Enforces HTTPS in production (1-year max-age)
• Rate Limiting - Three-tier protection:
  • Short: 3 requests/second
  • Medium: 20 requests/10 seconds
  • Long: 100 requests/minute
• Input Validation - Whitelist-based DTO validation
• No MIME Sniffing - Prevents content-type attacks

📝 Logging

The application uses Pino for high-performance structured logging:

// In your service
import { Logger } from '@nestjs/common';

private readonly logger = new Logger(YourService.name);

// Log messages
this.logger.log('Operation completed', 'context');
this.logger.error('Something went wrong', error.stack);

🔄 Generating Resources

Use the NestJS CLI to scaffold new resources:

# Generate a complete CRUD resource
nest g resource modules/your-resource

# Generate individual components
nest g controller modules/your-resource
nest g service modules/your-resource
nest g module modules/your-resource

📌 Conventional Commits

This project enforces Conventional Commits. Common prefixes:

Prefix	Description	Version Bump
feat:	New feature	Minor
fix:	Bug fix	Patch
docs:	Documentation only	-
refactor:	Code refactoring	-
test:	Adding tests	-
chore:	Maintenance	-
feat!: / fix!:	Breaking change	Major

🤝 Contributing

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

📄 License

This project is licensed under the MIT License - see the LICENSE file for details.

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