Docker Examples & Learning Repository

A comprehensive collection of Docker examples demonstrating containerization concepts from basic single-container applications to advanced multi-stage builds and orchestration with Docker Compose. This repository provides hands-on examples for learning Docker fundamentals and best practices.

📋 Table of Contents

• Project Overview
• Repository Structure
• Docker Examples
• Getting Started
• Learning Path
• Prerequisites
• Contributing

🎯 Project Overview

This repository serves as a practical learning platform for Docker containerization, covering:

• Basic Containerization with single-service applications
• Multi-container Applications using Docker Compose
• Production Optimization with multi-stage builds
• Service Orchestration and networking
• Real-world Applications (APIs, report generators, caching)
• Docker Best Practices and optimization techniques

📁 Repository Structure

Docker-Examples/
├── 📂 docker-basics/                    # Simple Flask app containerization
├── 📂 dynamic-report-generator/         # CSV report generation API
├── 📂 flask-redis-app/                 # Multi-service app with Docker Compose
├── 📂 multistage-pdf-generator/        # Optimized builds with multi-stage
├── 📄 readme-docker.md                 # Docker fundamentals guide
└── 📄 README.md                        # This file

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🐳 Docker Examples

Beginner Level

Docker Basics 🚀

Simple Flask App Containerization

Basic introduction to Docker containerization with a minimal Python Flask application.

Features:

• ✅ Simple Dockerfile - Basic container setup
• ✅ Flask Web App - "Hello World" web application
• ✅ Port Mapping - Exposing application to host
• ✅ Image Building - Creating custom Docker images

Quick Start:

cd docker-basics
docker build -t hello-docker .
docker run -p 5000:5000 hello-docker

Access: http://localhost:5000

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Dynamic Report Generator 📊

API-Based CSV Report Generation

Demonstrates building a REST API that generates CSV reports from JSON input.

Features:

• ✅ REST API - POST endpoint for data processing
• ✅ JSON to CSV - Dynamic report generation
• ✅ File Downloads - CSV file response handling
• ✅ Lightweight Container - Optimized Python image

Quick Start:

cd dynamic-report-generator
docker build -t dynamic-report-generator .
docker run -p 5000:5000 dynamic-report-generator

API Usage:

curl -X POST http://localhost:5000/generate-report \
  -H "Content-Type: application/json" \
  -d '[{"name":"John","age":30,"city":"NYC"}]'

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Intermediate Level

Flask + Redis App 🔄

Multi-Service Application with Docker Compose

Advanced example showing service orchestration with Docker Compose, featuring a Flask web app connected to Redis for caching.

Features:

• ✅ Docker Compose - Multi-container orchestration
• ✅ Service Networking - Container-to-container communication
• ✅ Redis Integration - Caching and data persistence
• ✅ Dependency Management - Service startup ordering
• ✅ Volume Mapping - Data persistence across restarts

Quick Start:

cd flask-redis-app
docker-compose up --build

Access: http://localhost:5000 (view counter increments with each refresh)

Services:

• Flask App: Web application server
• Redis: In-memory data store for caching

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Advanced Level

Multistage PDF Generator 📄

Production-Optimized Multi-Stage Build

Demonstrates advanced Docker techniques using multi-stage builds to create minimal, production-ready images.

Features:

• ✅ Multi-Stage Build - Separate build and runtime environments
• ✅ Image Optimization - Smaller final image size
• ✅ PDF Generation - Dynamic PDF creation with FPDF
• ✅ Security Best Practices - Minimal attack surface
• ✅ Production Patterns - Optimized for deployment

Quick Start:

cd multistage-pdf-generator
docker build -t pdf-generator .
docker run -p 5000:5000 pdf-generator

Build Stages:

1. Builder Stage: Install dependencies and build artifacts
2. Runtime Stage: Copy only necessary files for execution

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🚀 Getting Started

1. Install Docker

Windows/Mac:

• Download Docker Desktop from docker.com
• Follow installation instructions for your platform

Linux:

# Ubuntu/Debian
sudo apt update
sudo apt install docker.io docker-compose

# CentOS/RHEL
sudo yum install docker docker-compose

2. Verify Installation

# Check Docker version
docker --version

# Check Docker Compose version
docker-compose --version

# Test Docker installation
docker run hello-world

3. Clone Repository

git clone https://github.com/TheDataArtisanDev/Docker-Examples.git
cd Docker-Examples

4. Run Your First Example

# Start with basic example
cd docker-basics
docker build -t hello-docker .
docker run -p 5000:5000 hello-docker

Visit http://localhost:5000 to see your containerized application!

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📚 Learning Path

Fundamentals

1. Docker Concepts: Read readme-docker.md for theory
2. Basic Container: Docker Basics example
3. Docker Commands: Build, run, and manage containers

Intermediate Concepts

1. API Development: Dynamic Report Generator
2. Multi-Container Apps: Flask + Redis
3. Service Networking: Understanding container communication

Advanced Patterns

1. Build Optimization: Multistage PDF Generator
2. Production Deployment: Security and performance considerations
3. Orchestration: Docker Compose and service management

Production Readiness

1. Image Optimization: Multi-stage builds and layer caching
2. Security Practices: Minimal base images and user permissions
3. Monitoring: Health checks and logging strategies

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🛠️ Essential Docker Commands

Image Management

# Build image
docker build -t <image-name> .

# List images
docker images

# Remove image
docker rmi <image-name>

# Pull from registry
docker pull <image-name>

Container Operations

# Run container
docker run -p <host-port>:<container-port> <image-name>

# List running containers
docker ps

# Stop container
docker stop <container-id>

# Remove container
docker rm <container-id>

Docker Compose

# Start services
docker-compose up

# Build and start
docker-compose up --build

# Stop services
docker-compose down

# View logs
docker-compose logs <service-name>

Debugging

# Execute shell in running container
docker exec -it <container-id> /bin/bash

# View container logs
docker logs <container-id>

# Inspect container
docker inspect <container-id>

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🔧 Prerequisites

Software Requirements

• Docker Engine 20.10+
• Docker Compose 2.0+
• Git for repository cloning
• Web Browser for testing applications

System Requirements

• RAM: 4GB minimum, 8GB recommended
• Storage: 10GB free space for images
• OS: Windows 10+, macOS 10.14+, or modern Linux

Optional Tools

# Docker development tools
docker stats        # Resource monitoring
docker system df    # Disk usage
docker system prune # Cleanup unused resources

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💡 Real-World Applications

Web Development

• 🌐 Application Containerization: Package web apps with dependencies
• 🔄 Development Environment: Consistent dev environments across teams
• 🚀 Deployment: Simplified application deployment

Microservices

• 🏗️ Service Isolation: Independent service deployment
• 📡 API Integration: Container-to-container communication
• 📊 Load Balancing: Scaling individual services

DevOps & CI/CD

• ⚙️ Build Automation: Containerized build environments
• 🧪 Testing: Isolated testing environments
• 📦 Artifact Management: Version-controlled container images

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🤝 Contributing

This repository focuses on Docker education and practical examples. Contributions welcome:

• 💡 New Examples: Add more Docker patterns or use cases
• 🐛 Bug Fixes: Improve existing examples or documentation
• 📚 Documentation: Enhance explanations or add tutorials
• 🔧 Optimizations: Performance improvements or best practices

For major changes, please open an issue first to discuss your ideas.

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🔗 Useful Links

• Docker Official Documentation
• Docker Compose Documentation
• Docker Best Practices
• Dockerfile Reference
• Docker Hub

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Happy Containerizing! 🐳

This repository provides a comprehensive journey through Docker containerization. Use these examples to build production-ready containerized applications!