Python 3 image for Docker

About

A slim Python 3 image for Docker. Currently the resulting image contains Python 3.10, compiled from source and the pip and wheel packages are included.

This is heavily inspired from the official Python image at https://github.com/docker-library/python/blob/master/3.9/buster/slim/Dockerfile but has a few differences:

• use multi-stage build in Dockerfile to ease the build step and still get a small image
• build Python without the ncurses, readline and tk modules for image size, assuming a non-interactively used Python interpreter does not need these modules
• the Python interpreter is installed to /python

The Dockerfile uses debian:bullseye-slim (https://hub.docker.com/_/debian/) as base but this is configurable at build time using BASE_IMAGE_NAME as build argument. Tested with debian:buster-slim, debian:bullseye-slim and ubuntu:18.04, the Dockerfile generally should work with most Debian based base images.

Motivation

• Be able to specify a custom base image
• Have a Python Docker image as small as possible while still usable for most use cases

Build

Just build the image:

docker build --tag python3:latest .

Use a different base image:

docker build --build-arg BASE_IMAGE_NAME=ubuntu:bionic --tag python3:bionic .

Usage

By default, the Python interpreter is started when the image is ran:

docker run --rm -it --name python3 python3:latest

To change this, just overwrite the CMD instruction in your Dockerfile.

License

Licensed under the MIT License.

Author

Enrico Tröger enrico.troeger@uvena.de