Docker containerization in Flask - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is Docker containerization?

Docker containerization is a way to package an application and all its parts into a single container. This container can run anywhere, making the app easy to share and deploy.

beginner

Why use Docker with a Flask app?

Using Docker with Flask helps keep the app environment consistent. It ensures the app runs the same on your computer, a server, or in the cloud, avoiding "it works on my machine" problems.

intermediate

What is a Dockerfile in the context of Flask?

A Dockerfile is a simple text file with instructions to build a Docker image. For Flask, it usually tells Docker which Python version to use, copies your app code, installs dependencies, and sets how to start the app.

beginner

How does Docker help with dependencies in Flask projects?

Docker packages all dependencies inside the container. This means you don't need to install Python or libraries on your computer separately; the container has everything your Flask app needs.

intermediate

What is the difference between a Docker image and a Docker container?

A Docker image is like a recipe or blueprint for your app. A Docker container is the running instance of that image, like a cake made from the recipe.

What file do you use to define how to build a Docker image for a Flask app?

A Dockerfile

B requirements.txt

C app.py

D docker-compose.yml

The Dockerfile contains instructions to build the Docker image, including setting up the environment and copying your Flask app.

Which command runs a Docker container from an image?

A docker build

B docker pull

C docker push

D docker run

The 'docker run' command starts a container from a Docker image.

Why is containerization useful for Flask apps?

A It makes the app run faster on all computers

B It packages the app with its environment so it runs the same everywhere

C It automatically writes Flask code

D It replaces the need for Python

Containerization packages the app and its environment, ensuring consistent behavior across different machines.

What does the 'EXPOSE' instruction in a Dockerfile do?

A Specifies which port the container listens on

B Runs the Flask app

C Copies files into the container

D Installs dependencies

'EXPOSE' tells Docker which port the container will listen on for network connections.

Which of these is NOT a benefit of using Docker with Flask?

A Consistent environment across machines

B Simplifies deployment

C Automatically fixes bugs in Flask code

D Packages dependencies inside the container

Docker does not fix bugs in your code; it helps with environment consistency and deployment.

Explain how Docker containerization helps when deploying a Flask application.

Think about how Docker solves the 'works on my machine' problem.

Describe the role of a Dockerfile in creating a Docker container for a Flask app.

It's like a recipe for building your app's container.