devops-minitwit

ITU DevOps, Software Evolution and Software Maintenance (Spring 2026)

Tech Stack

• Language: Python 3.12
• Framework: FastAPI (not Flask — as required by session 02)
• ORM: SQLAlchemy (no raw SQL — as required by session 05)
• Database: SQLite (migrated to PostgreSQL in session 06)
• Container: Docker + Docker Compose
• CI/CD: GitHub Actions
• Hosting: DigitalOcean (Frankfurt, FRA1)

Why FastAPI? FastAPI provides automatic OpenAPI documentation, type safety via Python type hints, and modern async support — while keeping Python as the implementation language as required. It uses the same Jinja2 templating engine as Flask, making the migration straightforward.

Live Application

• Web UI: http://46.101.179.118:5000
• Simulator API: http://46.101.179.118:5000

Repository Structure

itu-minitwit/       # Original legacy Python 2 + Flask app (session 01)
minitwit/           # Refactored FastAPI app (session 02+)
  app.py            # Application routes and simulator API
  models.py         # SQLAlchemy ORM models (User, Message, Follower)
  schema.sql        # Original DB schema
  requirements.txt  # Python dependencies
  Dockerfile        # Container definition
  templates/        # Jinja2 HTML templates
  static/           # CSS
remote_files/       # Production deployment files
  docker-compose.yml
.github/workflows/
  ci.yml            # Run tests on every push
  cd.yml            # Build, push, deploy on main push
provision.sh        # Provision a new DigitalOcean droplet (session 03)

Deploying from scratch (session 03 task 2a+2b)

Step 1: Provision a new server

export DO_API_TOKEN=<your-digitalocean-api-token>
export SSH_KEY_ID=<your-ssh-key-id>
./provision.sh

To find your SSH key ID:

curl -X GET -H "Authorization: Bearer $DO_API_TOKEN" \
  "https://api.digitalocean.com/v2/account/keys"

Step 2: Deploy the application

SSH into the server and run:

ssh root@<server-ip>
apt-get update && apt-get install -y docker.io
mkdir -p /usr/local/lib/docker/cli-plugins
curl -SL https://github.com/docker/compose/releases/download/v2.24.0/docker-compose-linux-x86_64 \
  -o /usr/local/lib/docker/cli-plugins/docker-compose
chmod +x /usr/local/lib/docker/cli-plugins/docker-compose
systemctl start docker && systemctl enable docker
mkdir -p /minitwit
curl -o /minitwit/docker-compose.yml \
  https://raw.githubusercontent.com/Armaaan/devops-minitwit/main/remote_files/docker-compose.yml
cd /minitwit && docker compose up -d

The application will be available at http://<server-ip>:5000.

Running locally

git clone https://github.com/Armaaan/devops-minitwit.git
cd devops-minitwit
docker compose up --build

Open http://localhost:5001/public

Running tests

cd minitwit
python3 -m venv venv && source venv/bin/activate
pip install -r requirements.txt pytest httpx
pytest minitwit_tests.py -v

CI/CD Pipeline

Every push to main:

1. CI — runs minitwit_tests.py (4 integration tests)
2. CD — builds Docker image, pushes to Docker Hub, deploys to server

Session Progress

Session	Task	Status
01	Python 3 migration	✅
02	FastAPI refactor + Docker	✅
03	Simulator API + DigitalOcean deploy	✅
04	GitHub Actions CI/CD	✅
05	SQLAlchemy ORM (no raw SQL)	✅