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Use-Case Project: Apply Docker Container Best Practices

Docker Container Best Practices

Situation​

You got a sample JavaScript application, it's a simple todo list manager that is running in Node.js, however, no real JavaScript experience is needed. We will just run it.

Task​

  • Create a Dockerfile to containerize project.
  • Apply Docker container best practices to work effectively with top ✅️ Dos & 🚫 Don'ts.
  • Create a CI pipeline to automate the best practices checks.

Requirements​

Ensure the following best practices are applied.

  • 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

  • Misc Practices

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

Extras​

Build:

docker build . -t docker-sample-app:v1

Run:

docker run -p 3000:3000 docker-sample-app:v1

View:

http://localhost:3000

Resources​

Reference​

tip

Once you are done, compare your solution with the reference.

Ensure that you understand all aspects of the reference.