Project Title

A brief description of what this project does and who it's for

🎨 Custom Photo QR Generator

This is a Streamlit application that allows users to create customizable QR codes with the option of adding overlaying photos in the background and still getting an easily-recognized QR code. Most free tools online limit your ability to change shapes or add logos or at least hides it behind a paywall or a free trial; this project aims to provide that flexibility for free while maintaining high-quality output.

🧠 The Learning Journey (Why this matters)

This project's aim was a mix of interest in QR code beautification in python and a desire to apply Docker best practices I learnt with guidance from the Project "Container Best Practices" in the Dynamic DevOps Roadmap.

• Modern Package Management: Switched to uv by Astral. I chose this because it is significantly faster than pip and provides a uv.lock file for 100% reproducible environments and more reusable than requirement.txt files.

• Efficient Containerization: I optimized my Dockerfile with Docker Best Practices in mind.

🛠️ Tech Stack

• Core Logic: Segno (QR generation), Pillow (Image processing).
• Front-end: Streamlit.

• Dependency Management: uv

• DevOps: Docker.

🚀 Running the App

Prerequisites

You just need to have Docker installed on your system.

1. Run the Container: The image currently resides on Dockerhub registry.

docker run --rm -d -p 8501:8501/tcp menna011/custom-qr-app:2.1

2. View the App: Open http://127.0.0.1:8501 in your browser.

⏭️ Applied Best Practices

• Essential Practices

  • Use Dockerfile linter 🟢
  • Check Docker language specific best practices 🟢
  • Create a single application per Docker image 🟢
  • Create configurable ephemeral containers 🟢

• Image Practices

  • Use optimal base image 🟢
  • Pin versions everywhere 🟢
  • Create image with the optimal size 🟡
  • Use multi-stage whenever possible 🟢
  • Avoid any unnecessary files 🟡

• Security Practices

  • Always use trusted images 🟢
  • Never use untrusted resources 🟢
  • Never store sensitive data in the image 🟢
  • Use a non-root user 🟢
  • Scan image vulnerabilities 🟢 (Trivy)

• Misc Practices

  • Leverage Docker build cache 🟢
  • Avoid system cache 🟢
  • Create a unified image across envs 🟡
  • Use ENTRYPOINT with CMD 🟢

🚀 Learned lessons and what I would do differently in future Projects

• Automated CI/CD Pipeline: Instead of manual building, I would set up GitHub Actions or Jenkins. Every time I push code, the image would be automatically built, scanned for vulnerabilities, and pushed to the registry.

• Package Management Issues: Packages using entry-point plugins (like qrcode-artistic for this project) must be explicitly declared in pyproject.toml and correctly registered in the .venv inside the image to be recognized by the main library.

• Using the Official Docker: I Diagnosed and resolved "Permission Denied" errors caused by the Snap version of Docker's security confinement, and therefore installed the official docker, which made working with docker better.

• Secret Management: Right now, the app is simple, but if I added a database or API keys, I would move away from ENV variables in the Dockerfile and use a secure secret manager or .dockerignore combined with encrypted secrets.

• Deploying app to the cloud: This time, I didn't have the time or resources to deploy the app onto the cloud, so I'd like to try doing that in the near future whether it's this app or another one.