feat: Add Docker Compose setup for local development

[LeSoviet]

🐳 Docker Setup Implementation

Adds complete Docker Compose configuration for easy local development without manual PostgreSQL installation.

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📋 Changes

New Files

• ✅ docker-compose.yml - Orchestrates PostgreSQL, backend, and frontend services
• ✅ apps/backend/Dockerfile - Multi-stage build with Node 18 Alpine, pnpm, and Prisma
• ✅ apps/frontend/Dockerfile - Vite dev server with hot module replacement
• ✅ apps/backend/.dockerignore - Optimizes build context for backend
• ✅ apps/frontend/.dockerignore - Optimizes build context for frontend

Modified Files

• ✅ README.md - Added "Quick Start with Docker" section at the top

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✨ Features

Services

• PostgreSQL 14 Alpine - Database with health check
• Backend (Node 18 Alpine) - Auto-migrates and seeds on first run
• Frontend (Node 18 Alpine) - Vite dev server with HMR enabled

Developer Experience

• ✅ Zero Configuration - No need to install PostgreSQL, Node.js, or pnpm
• ✅ One Command Start - docker compose up --build
• ✅ Hot Reload - Changes to source code automatically reload services
• ✅ Persistent Data - PostgreSQL data persists in Docker volume
• ✅ Health Checks - Backend waits for PostgreSQL to be healthy
• ✅ Isolated Environment - Clean, reproducible development setup

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🚀 Quick Start

With Docker (Recommended)

# Start all services
docker compose up --build

# Application will be available at:
# - Frontend: http://localhost:5173
# - Backend: http://localhost:3000
# - PostgreSQL: localhost:5432

Useful Commands

# Start in background
docker compose up -d

# View logs
docker compose logs -f backend
docker compose logs -f frontend

# Stop services
docker compose down

# Reset database (remove volume)
docker compose down -v

# Run tests in Docker
docker compose exec backend pnpm --filter backend test
docker compose exec frontend pnpm --filter frontend test --run

# Open Prisma Studio
docker compose exec backend pnpm --filter backend prisma:studio

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🧪 Testing

Tested Scenarios

• ✅ Fresh installation (clean database)
• ✅ Hot reload for backend code changes
• ✅ Hot reload for frontend code changes
• ✅ Hot reload for shared types changes
• ✅ Database persistence across restarts
• ✅ Auto-migration on first run
• ✅ Auto-seeding with 10 sample orders
• ✅ All 15 tests passing (10 backend + 5 frontend)

Test Results

# Backend Tests
docker compose exec backend pnpm --filter backend test
# ✅ 10 tests passing

# Frontend Tests
docker compose exec frontend pnpm --filter frontend test --run
# ✅ 5 tests passing

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📊 Docker Image Sizes

Service	Base Image	Final Size (approx)
PostgreSQL	postgres:14-alpine	~230MB
Backend	node:18-alpine	~450MB
Frontend	node:18-alpine	~450MB
Total		~1.1GB

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🎯 Requirements Checklist

This PR completes the final bonus point from the original requirements:

Core Requirements

• ✅ Backend CRUD with TypeScript + Express + PostgreSQL
• ✅ Frontend with React 19 + TypeScript
• ✅ Pagination and filtering
• ✅ All required endpoints implemented
• ✅ Proper TypeScript types everywhere

Bonus Points

• ✅ Status filtering (backend + frontend)
• ✅ Comprehensive testing (15 tests)
• ✅ Shared types monorepo setup
• ✅ Comprehensive documentation
• ✅ ESLint + Prettier configuration
• ✅ Professional error handling
• ✅ Toast notifications
• ✅ Postman collection
• ✅ Docker setup for easy local development 🐳 ← THIS PR

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📹 Video Walkthrough

[Add YouTube/Loom link here - 5 min max]

Video includes:

1. Project architecture overview
2. Code walkthrough (monorepo, shared types, controllers)
3. Demo with Docker (docker compose up)
4. Full CRUD operations demo
5. Testing execution
6. Bonus features showcase

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🔍 Code Review Notes

Docker Compose Configuration

• Uses version: '3.8' for compatibility
• Health check on PostgreSQL ensures backend starts after DB is ready
• Volume mounts enable hot reload for development
• Named volumes persist database data
• Bridge network isolates services

Dockerfile Best Practices

• Multi-stage builds for optimization
• Alpine base images for smaller size
• Layer caching with separate dependency installation
• .dockerignore files exclude unnecessary files
• Non-root user for security (inherited from node:alpine)

Auto-Migration Strategy

• Backend runs prisma migrate deploy on startup
• Seeds database only if empty
• Idempotent seed script prevents duplicate data

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💡 Usage Tips

For Development

# Make changes to code - they'll reload automatically
# Backend: tsx watch mode
# Frontend: Vite HMR
# Shared types: Changes reflect immediately

For Testing

# You can run tests while services are running
docker compose exec backend pnpm --filter backend test

For Database Management

# Access Prisma Studio
docker compose exec backend pnpm --filter backend prisma:studio
# Opens at http://localhost:5555

For Debugging

# View logs in real-time
docker compose logs -f

# Access container shell
docker compose exec backend sh
docker compose exec frontend sh

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🐛 Known Issues

None at the moment. All services start successfully and hot reload works as expected.

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📝 Additional Notes

• Docker Compose v2 syntax used (docker compose instead of docker-compose)
• Windows users: Ensure WSL 2 is installed and updated
• First build takes ~5-10 minutes due to dependency installation
• Subsequent starts are much faster (~30 seconds)
• Database volume persists across docker compose down
• Use docker compose down -v to reset database

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Ready for review! 🚀

This PR can be merged into Order-Management-System-with-both-frontend-and-backend, and then the entire feature branch can be merged to main.