Demo Devops Python

This is a simple application to be used in the technical test of DevOps. The application can be accessed at https://stevencode.dev/api/

Getting Started

Prerequisites

• Python 3.13
• Docker and Docker Compose
• Terraform (for infrastructure deployment)
• Pipenv (for virtual environment management)
• Git

Installation

Option 1: Traditional Python Setup

Clone this repo.

git clone https://github.com/StevenMartinez94/devsu-test/
cd devsu-test

Install dependencies.

pip install -r requirements.txt

Option 2: Using Pipenv (Recommended)

Clone this repo.

git clone https://github.com/StevenMartinez94/devsu-test/
cd devsu-test

Install Pipenv if you haven't already:

pip install pipenv

Install dependencies and create virtual environment:

pipenv install

Activate the virtual environment:

pipenv shell

Option 3: Using Docker

Clone this repo.

git clone https://github.com/StevenMartinez94/devsu-test/
cd demo-devops-python

Build and run with Docker Compose:

docker-compose up --build

Database

The database is generated as a file in the main path when the project is first run, and its name is db.sqlite3. Consider giving access permissions to the file for proper functioning.

Migrate database (not if using Docker):

python manage.py makemigrations
python manage.py migrate

Usage

Running the Application

Local Development

To run tests you can use this command.

python manage.py test

To run locally the project you can use this command.

python manage.py runserver

Using Pipenv

# Run tests
pipenv run python manage.py test

# Run the development server
pipenv run python manage.py runserver

Using Docker

The application will be automatically available at http://localhost:8000 when using Docker Compose. Open http://localhost:8000/api/ with your browser to see the result.

DevOps & Infrastructure

Diagram

Notes

Why on-premises? The main reason for choosing on-premises deployment here is to demonstrate the ability to set up a Kubernetes cluster on a bare-metal server, which is a common scenario in DevOps practices. Also, on-premises deployment offers greater control over the infrastructure and data, which can be crucial for certain applications and compliance requirements.

Why Contabo? Contabo provides affordable cloud infrastructure with reliable performance, making it suitable for deploying small applications. For production, I would rather consider using a more robust provider like AWS or GCP.

What else I would need to deploy a project like this? You would need a domain name and to apply some k8s manifest as:

# Install cert-manager for automated TLS certificates
kubectl apply -f https://github.com/cert-manager/cert-manager/releases/latest/download/cert-manager.yaml

# Install MetalLB for bare-metal load balancing
kubectl apply -f https://raw.githubusercontent.com/metallb/metallb/v0.15.2/config/manifests/metallb-native.yaml

# Install ingress-nginx for HTTP ingress routing
kubectl apply -f https://github.com/kubernetes/ingress-nginx/blob/main/deploy/static/provider/baremetal/deploy.yaml

Docker

This project includes Docker support for containerized deployment.

Docker Components

• Dockerfile: Multi-stage build with Python 3.13-slim base image
• docker-compose.yml: Local development orchestration
• Security: Runs as non-root user (apiuser:1000)
• Health Checks: Built-in health monitoring at /api endpoint
• Logging: JSON file driver with rotation (10MB max, 3 files)

Docker Commands

# Build the image
docker build -t restful-api .

# Run with Docker Compose
docker-compose up -d

# View logs
docker-compose logs -f restful-api

# Stop services
docker-compose down

# Rebuild and restart
docker-compose up --build --force-recreate

Terraform Infrastructure

The project includes Terraform configuration for deploying Kubernetes infrastructure on Contabo cloud provider.

Infrastructure Components

• 3 Contabo instances: 1 master + 2 worker nodes
• Kubernetes cluster: Ready for application deployment

Terraform Commands

cd terraform

# Initialize Terraform
terraform init

# Plan the deployment
terraform plan

# Apply the infrastructure
terraform apply

# View outputs (IPs, instance IDs)
terraform output

# Destroy infrastructure
terraform destroy

Required Variables

Create a terraform.tfvars file with:

oauth2_client_id     = "your-contabo-client-id"
oauth2_client_secret = "your-contabo-client-secret"
oauth2_user          = "your-contabo-user"
oauth2_pass          = "your-contabo-password"
product_id           = "your-product-id"
region               = "your-region"
image_id             = "your-image-id"

Kubernetes Deployment

The k8s/manifests/ directory contains Kubernetes deployment files:

• namespace.yaml: Application namespace
• deployment.yaml: Application deployment configuration
• service.yaml: Service exposure
• ingress.yaml: Ingress rules and certificate setup
• pv.yaml & pvc.yaml: Persistent volume configuration

NOTE: You may need to create a Kubernetes secret for the Django secret key inside the demo-app namespace, you can do it using the following command:

kubectl create secret generic demo-app-secrets \
  --namespace=demo-app \
  --from-literal=django-secret-key='your-django-secret-key'

GitHub Actions CI/CD

The project implements a comprehensive CI/CD pipeline using GitHub Actions with 6 automated workflows that ensure code quality, security, and reliable deployments.

Workflow Overview

The CI/CD pipeline follows a sequential execution pattern:

Lint → Build & Test → Docker Build → Vulnerability Scan & Code Coverage → Deploy

CI/CD Workflow Summary

The project uses six GitHub Actions workflows for automated quality, security, and deployment:

1. Lint: Checks Python, YAML, and Terraform formatting.
2. Build & Test: Runs Django tests after linting, using secrets for configuration.
3. Docker Build & Push: Builds and pushes Docker images to GHCR after tests pass.
4. Vulnerability Scan: Scans built images for security issues using Trivy.
5. Code Coverage: Measures and reports test coverage.
6. Deploy: Deploys to Kubernetes using updated manifests and secrets.

Required GitHub Repository Secrets

To enable full CI/CD functionality, configure these secrets in your repository:

# Django Application
DJANGO_SECRET_KEY=your-secure-django-secret-key

# Kubernetes Deployment
KUBECONFIG_B64=base64-encoded-kubeconfig-content

How to Generate Required Secrets

Django Secret Key:

python -c "from django.core.management.utils import get_random_secret_key; print(get_random_secret_key())"

Kubeconfig (Base64):

# Encode your kubeconfig file
cat ~/.kube/config | base64 -w 0

Workflow Features

Security Features:

• Container image scanning for OS and application vulnerabilities
• SARIF security reporting format

Quality Assurance:

• Multi-language linting (Python, YAML, Terraform)
• Automated testing
• Code coverage reporting

Deployment Features:

• Tag-based versioning
• Automatic image tagging
• Rolling deployments to Kubernetes
• Multi-environment support

Container Registry:

• GitHub Container Registry (GHCR) integration
• Automatic image cleanup and tagging
• Multi-architecture support ready

Local Development Integration

Developers can run similar checks locally:

# Run linting checks
black --check .
yamllint .
terraform fmt -check -recursive

# Run tests
python manage.py test api

# Build Docker image locally
docker build -t restful-api:local .

Environment Variables

Create a .env file for local development:

DJANGO_SECRET_KEY=your-django-secret-key
DATABASE_NAME=db.sqlite3

Monitoring & Logging

Docker Logging

Logs are configured with rotation to prevent disk space issues:

logging:
  driver: json-file
  options:
    max-size: 10m
    max-file: "3"

Health Checks

The application includes health monitoring:

healthcheck:
  test: ["CMD", "curl", "-f", "http://localhost:8000/api"]
  interval: 30s
  timeout: 10s
  retries: 5

API Documentation

Features

These services can perform:

Create User

To create a user, the endpoint /api/users/ must be consumed with the following parameters:

  Method: POST

{
    "dni": "dni",
    "name": "name"
}

If the response is successful, the service will return an HTTP Status 200 and a message with the following structure:

{
    "id": 1,
    "dni": "dni",
    "name": "name"
}

If the response is unsuccessful, we will receive status 400 and the following message:

{
    "detail": "error"
}

Get Users

To get all users, the endpoint /api/users must be consumed with the following parameters:

  Method: GET

If the response is successful, the service will return an HTTP Status 200 and a message with the following structure:

[
    {
        "id": 1,
        "dni": "dni",
        "name": "name"
    }
]

Get User

To get an user, the endpoint /api/users/ must be consumed with the following parameters:

  Method: GET

If the response is successful, the service will return an HTTP Status 200 and a message with the following structure:

{
    "id": 1,
    "dni": "dni",
    "name": "name"
}

If the user id does not exist, we will receive status 404 and the following message:

{
    "detail": "Not found."
}

License

Copyright © 2023 Devsu. All rights reserved.