wip: TestRig

utility container for linting and testing existing uninstrumented Python containers

How this works:

We create a virtualenv with linting and testing packages (bandit, black, flake8, isort, mypy, pycodestyle, pylint, pytest) -- for specific versions of python on specific distros.
You create a persistent volume called testrig (in your compose file or manually)
You run the TestRig container once (aka "testrig-setup") and it rsyncs this virtualenv to your /testrig persistent volume.
When you want to test a python app, you run it's container with the /testrig persistent volume attached and the entrypoint set to /testrig/run.

This scheme means the linting and testing packages bring their own dependencies via the /testrig persistent volume, the app's dependencies are already in the container image. The testing utils can load all the tested app's dependencies exactly as the app normally does. You get to fully lint & test a production container image without having to bake in any additional infrastructure.

TestRig uses config keys found in setup.cfg to control the directory walking it does for pylint and the exclusions it passes to bandit.

Docker Images

This repo's images are automatically published to backplane/testrig on Docker Hub. Tags are in the format {testrig_semver}-{python_version}-{distro_version} (for example: v0.8.0-3.7-alpine3.14). In addition, the latest version of each distro image is available with these tags:

backplane/testrig:latest-3-slim - for use testing Python code in Debian-based containers
backplane/testrig:latest-3-alpine - for use testing Python code in Apline-based containers

Other images

The tags are currently a bit of a mess; they're created by a build-matrix with the goal of letting users lock to: a specific version of testrig, built for a specific version of Python, on a specific version of Apline or Debian.

I'd suggest starting with:

latest for TestRig version
the same minor version of Python the app under test is using
slim for Debian containers or alpine for Apline containers
that's latest-3.9-slim for Python 3.9 app in a Debian container.

demo

docker-compose build alpine demoapp
docker-compose run --rm testrig-setup # only needed once
docker-compose run --rm testrig

License Note

The AGPL v3 LICENSE in this repo covers only the code in the repo, the built docker images contain various software packages which have their own licenses.

Misc Dev Notes

docker "platform"	"arch" command output
`amd64`	`x86_64`
`arm64`	`aarch64`
`arm/v7`	`armv7l`