Speed up workflows with Docker images

[redeboer]

APT installs are time consuming, see for instance this log. It can be sped up by creating a Docker container on hub.docker.com/orgs/compwa and pulling it in the workflow with container.image.

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Example for that specific log (2m48s).

1. Create a Dockerfile:

   FROM python:3.8
   RUN apt-get -y update
   
   # https://serverfault.com/a/992421
   RUN DEBIAN_FRONTEND=noninteractive TZ=Etc/UTC apt-get -y install tzdata
   RUN apt-get -y install inkscape latexmk make texlive-fonts-extra texlive-xetex xindy
   
   RUN apt-get autoclean -y
   RUN apt-get autoremove -y
   RUN rm -rf /var/lib/apt/lists/*

2. Build the image and push to Docker Hub:

   REPO=polarimetry
   JOB=fast-pdf
   docker build -t compwa/$REPO-$JOB .
   docker push compwa/$REPO-$JOB

This workflow was sped up by two minutes, see this log (57s container initialisation).

[redeboer]

Unfortunately, Docker is retiring its Free Team organization tier as of April 14th, 2023.
https://web.docker.com/rs/790-SSB-375/images/privatereposfaq.pdf

[redeboer]

The plan to sunset Free Team has been reverted 🎉

[redeboer]

But better: use https://ghcr.io instead