🚀 Python FastAPI CI/CD Pipeline with Jenkins & Docker

A lightweight, production-ready Python FastAPI microservice featuring automated testing with pytest, containerization, robust health checking, and a fully automated CI/CD deployment pipeline powered by Jenkins and Docker.

🛠️ Tech Stack & Tools

• Backend: Python 3.11, FastAPI, Uvicorn
• Testing: Pytest, HTTPX (TestClient)
• Containerization: Docker, Docker Compose
• CI/CD Automation: Jenkins (Declarative Pipeline)
• Version Control: Git & GitHub

📂 Project Structure

├── main.py              # FastAPI application entry point
├── test_main.py         # Automated API tests using pytest
├── requirements.txt     # Python project dependencies
├── Dockerfile           # Docker image configuration for the API
└── jenkins/
    └── Jenkinsfile      # CI/CD pipeline definition

📋 Prerequisites & Required Plugins

To run and deploy this project locally using Jenkins and Docker, ensure you have the following installed and configured:

1. System Requirements

• Docker & Docker Compose installed on your host machine.
• Linux/Debian-based environment (recommended for Docker socket mapping).

2. Jenkins Setup & Plugins

Your Jenkins container must have access to the host's Docker daemon to build and deploy containers from the pipeline.

• Docker-in-Docker / Docker-outside-of-Docker (DooD): Configured via volume mounting (/var/run/docker.sock).
• Jenkins Plugins:
• Git Plugin (for repository checkout)
• Pipeline Plugin (for declarative pipeline support)
• Docker Pipeline Plugin (optional, if using agent-level docker blocks)

🚀 Getting Started Locally

1. Clone the Repository

git clone https://github.com/your-username/your-repo-name.git
cd your-repo-name

2. Run Jenkins via Docker Compose

Start your local Jenkins server with Docker socket access enabled:

docker compose up --build -d

Access Jenkins at http://localhost:8080.

3. Run the FastAPI App Locally (Optional)

If you want to run the application manually without Jenkins:

# Install dependencies
pip install -r requirements.txt

# Run the development server
uvicorn main:app --reload --port 8000

Open your browser and navigate to http://localhost:8000/docs to view the interactive Swagger documentation.

🔄 CI/CD Pipeline Workflow

The pipeline defined in the Jenkinsfile automates the entire software delivery lifecycle through the following stages:

1. Checkout SCM: Pulls the latest source code from the GitHub repository.
2. Run Tests: Executes automated pytest suites to validate application logic.
3. Build Docker Image: Packages the FastAPI application into a lightweight, optimized Docker container.
4. Deploy Container: Automatically stops any legacy container instances and boots up the fresh build on port 8000.
5. Health Check: Executes an automated internal validation probe (docker exec) targeting the /health endpoint to guarantee the application initialised successfully and is ready to accept production traffic.
6. Post Execution (always): Automatically triggers a clean-up step (docker image prune) to keep the host disk free of dangling build cache images.

📸 Screenshots & Demo

1. Jenkins Pipeline Execution Success

2. FastAPI Interactive Swagger Documentation

3. Jenkins Health Check