These images are heavy influenced by SeleniumHQ docker images. However, there are some differences.
The base image for the SeleniumHQ images are ubuntu:16.04 and have selenium-server installed. We have based our images on python:3.7.0-stretch. This allows us to copy our pytest automation source code into the container without needing to run extra commands to install Python.
We also like to keep our Python version up-to-date as possible, hence the use of Python 3.7. The use of Debian stretch/jessie is consistent with other docker builds utilized by other OpenStax teams.
The SeleniumHQ docker build files are licensed under APLv2 which is included in our license file.
The images are all kept up to date w/ the version of Chrome driver by using Concourse.
The Concourse pipeline file is located ../.concourse/build-and-push-selenium.yml.
The pipeline will detect when new versions of chromedriver-stable are released and update each of the images.