Python Exchange Rate App - CI/CD Pipeline

A Flask-based web application that displays real-time Nigerian Naira (NGN) to US Dollar (USD) exchange rates with automated CI/CD deployment to AWS EC2. This project will enhance your understanding of Python, Flask framework, Docker, AWS EC2 and storage of container Images in a private ECR repository.

🚀 Features

• Real-time Exchange Rates: Fetches current NGN/USD exchange rates from ExchangeRate-API
• Web Interface: Clean, responsive web UI displaying exchange rates
• Command Line Support: Can be run from terminal for quick rate checks
• Dockerized: Containerized application for consistent deployment
• CI/CD Pipeline: Automated deployment using GitHub Actions
• AWS Integration: Deployed on EC2 with ECR for container registry

🏗️ Architecture

┌─────────────────┐    ┌──────────────┐    ┌─────────────────┐
│   GitHub Repo   │───▶│ GitHub Actions│───▶│   AWS ECR       │
└─────────────────┘    └──────────────┘    └─────────────────┘
                              │                       │
                              ▼                       ▼
                       ┌──────────────┐    ┌─────────────────┐
                       │   Build &    │    │   AWS EC2       │
                       │   Push Image │    │   (Production)  │
                       └──────────────┘    └─────────────────┘

📋 Prerequisites

• Python 3.9+
• Docker
• AWS Account with ECR and EC2 access
• GitHub repository with Actions enabled

🛠️ Local Development

Setup

1. Clone the repository

   git clone <repository-url>
   cd Python-app---CI-CD

2. Install dependencies

   pip install -r requirements.txt

3. Run the application

   python app.py

4. Access the application

   • Web interface: http://localhost:5000
   • Command line: Run python app.py and check terminal output

Docker Development

1. Build the image

   docker build -t exchange-rate-app .

2. Run the container

   docker run -p 5000:5000 exchange-rate-app

🚀 Deployment

AWS Infrastructure Setup

1. Create ECR Repository

   aws ecr create-repository --repository-name tekktribe --region eu-west-2

2. Launch EC2 Instance

   • AMI: Amazon Linux 2
   • Instance Type: t2.micro (or preferred)
   • Security Group: Allow HTTP (80) and SSH (22)
   • Install Docker and AWS CLI

3. Configure EC2 Instance

   # Install Docker
   sudo yum update -y
   sudo yum install -y docker
   sudo systemctl start docker
   sudo systemctl enable docker
   sudo usermod -a -G docker ec2-user
   
   # Install AWS CLI
   sudo yum install -y aws-cli

GitHub Secrets Configuration

Add the following secrets to your GitHub repository:

Secret Name	Description
AWS_ACCESS_KEY_ID	AWS Access Key ID
AWS_SECRET_ACCESS_KEY	AWS Secret Access Key
EC2_HOST	EC2 instance public IP/hostname
EC2_USER	EC2 username (usually ec2-user)
EC2_SSH_KEY	Private SSH key for EC2 access

CI/CD Pipeline

The GitHub Actions workflow (.github/workflows/pipeline.yml) automatically:

1. Triggers on push/PR to main branch
2. Builds Docker image with commit SHA and latest tags
3. Pushes images to AWS ECR
4. Deploys to EC2 by:
   • Stopping existing containers on port 80
   • Pulling latest image from ECR
   • Running new container on port 80

📁 Project Structure

Python-app---CI-CD/
├── .github/
│   └── workflows/
│       └── pipeline.yml          # CI/CD pipeline configuration
├── app.py                        # Main Flask application
├── Dockerfile                    # Container configuration
├── requirements.txt              # Python dependencies
├── deploy.sh                     # Manual deployment script
├── LICENSE                       # Project license
└── README.md                     # Project documentation

🔧 Configuration

Environment Variables

Variable	Default	Description
AWS_REGION	eu-west-2	AWS region for ECR/EC2
ECR_REPOSITORY	tekktribe	ECR repository name

Application Settings

• Port: 5000 (container) → 80 (host)
• API: ExchangeRate-API (free tier)
• Update Frequency: Real-time on page refresh

🔍 API Reference

Endpoints

• GET / - Display exchange rates in web interface

External API

• Provider: ExchangeRate-API
• Endpoint: https://open.er-api.com/v6/latest/USD
• Rate Limit: 1,500 requests/month (free tier)

🐛 Troubleshooting

Common Issues

1. Port 80 already in use

   • Pipeline automatically kills processes using port 80
   • Manual fix: sudo fuser -k 80/tcp

2. ECR authentication failed

   • Verify AWS credentials in GitHub secrets
   • Check ECR repository exists in correct region

3. EC2 connection failed

   • Verify EC2 security group allows SSH (22) and HTTP (80)
   • Check SSH key format in GitHub secrets

Logs

• Application logs: docker logs python-app
• GitHub Actions: Check Actions tab in repository
• EC2 system logs: /var/log/messages

🔒 Security

• AWS credentials stored as GitHub secrets
• Docker containers run with non-root user
• Security groups restrict access to necessary ports only
• Regular dependency updates via Dependabot

📈 Monitoring

• Health Check: Access application URL
• Container Status: docker ps
• Resource Usage: docker stats python-app

🤝 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

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

🙋‍♂️ Support

For support and questions:

• Create an issue in the GitHub repository
• Check troubleshooting section above
• Review GitHub Actions logs for deployment issues
•