Cfn-python-lint: Official docker image

[xiaket]

This will put some extra burden on the developers, especially during the release process, but this will help out the following scenarios:

1. People of no python knowledge can simply try the tool without much effort.
2. Some CI/CD pipelines where the installation of either python or a python package would mean extra work.

Please let me know what you think, and please feel free to turn this down. I'm happy to create a PR if you guys want to go down this path. :)

[kddejong]

I have some internal tasks to get this going but wanted to let you know I have started this work.

[mrpackethead]

This is a bit of a challenge, as in some environments using docker images becomes a tricky challenge for security reasons, as we have to pick them all apart to assess if its safe.

[xiaket]

IMHO this is a good alternative to the current pip installation method, you can always choose to install through pip if you have other requirements to fulfill. :)

[gliptak]

Initial Docker file was merged https://github.com/aws-cloudformation/cfn-python-lint/pull/1361

[gliptak]

How would upload to https://hub.docker.com/ happen?

PS There is an unofficial version at https://hub.docker.com/r/aztek/cfn-lint

[atkinsonm]

Please publish to DockerHub :pray:

[jacksgt]

I agree, an official image on DockerHub (with tags for each release) would be great.
Since the Dockerfile is already in place, just setting up an automatic DockerHub build for the repository will not be too difficult.

Currently, there are many unofficial images out there, but for all of them we cannot know how they are build and how long they will be updated:
https://hub.docker.com/search?q=cfn-python-lint&type=image
https://hub.docker.com/search?q=cfn-lint&type=image

Thus, an official image would be greatly appreciated.
As mentioned in the original issue, it would simplify the setup for many people and also in CI/CD pipelines.