Support Multiple Versions of Terraform/OpenTofu

[RafaelWO]

Hi,

I am a big fan of this project and have been actively using your Docker images for over a year now. 🙏

We manage our cloud stack with Terragrunt and use devopsinfra/docker-terragrunt in CI/CD for the deployment. Over the course of this year, multiple Terraform versions have been released (1.10 - 1.13). While upgrading Terragrunt is usually straightforward, we can only slowly and carefully upgrade Terraform due to the large number of modules scattered across projects, which all come together in the deployment. (We still use Terraform 1.9).

Therefore, it would be very helpful if this project could support multiple versions of Terraform or OpenTofu. For example:

• devopsinfra/docker-terragrunt:tf-1.13.0-tg-0.86.2 (currenlty supported)
• devopsinfra/docker-terragrunt:tf-1.12.2-tg-0.86.2
• devopsinfra/docker-terragrunt:tf-1.11.4-tg-0.86.2
• ...

I took a look at the Makefile which seems to be the heart of the build and publish workflow, and I could imagine that adding a matrix parameter for the Terraform/OpenTofu versions that overwrites the version, e.g. TF_VERSION could be an option.

...
      matrix:
        flavour: [slim, plain, aws, azure, gcp, aws-azure, aws-gcp, azure-gcp, aws-azure-gcp]
        tf-version: [1.13.0, 1.12.2, 1.11.4]
...
        run: |
          docker buildx create --use
          make login
          make push-${{ matrix.flavour }} TF_VERSION=${{ matrix.tf-version }}
...

What do you think?

[ChristophShyper]

Hi,

Thank you for kind words. I'm so glad you find it useful :)

Docker repo is already over 15TB, as there are multiple images per each release. And DockerHub doesn't have API for removing stale images so I'm trying not to blow them :/ I even started to make releases not so often to decrease size growth.

Regarding updating only Terragrunt and leaving older versions of Terraform and OpenTofu is valid point.
I'll think about it if I'll have spare time.

[RafaelWO]

Docker repo is already over 15TB, as there are multiple images per each release. And DockerHub doesn't have API for removing stale images so I'm trying not to blow them :/ I even started to make releases not so often to decrease size growth.

I totally understand that!

Regarding updating only Terragrunt and leaving older versions of Terraform and OpenTofu is valid point.
I'll think about it if I'll have spare time.

I'm happy to support and create a PR if you want to tackle this or have an idea on how this could work 🙂

[ChristophShyper]

@RafaelWO I've been coming back to this issue and trying to grasp from different angles.
Docker images take a lot of space - docker repo was 15 TB, now is 10 TB and slowly shrinking as I try to remove stale images. I'd like to keep only the most recent and most pull images. And a single one is currently almost 1 GB, so a full set 9 flavors for 2 architectures takes a lot of space.

But after the last refactor it's easy to just create images for a specific combination of Terragrunt, Terraform and OpenTofu.
After forking the repo, with GHA workflow (Manual) Update Version you can simply build any version combination.

[RafaelWO]

@ChristophShyper thanks for coming back to this, I really appreciate that!

I understand that the number of images can explode due to combinatorics if you support multiple versions.

Thanks for the hint regarding building specific combinations via a fork. Do you know how a fork will be configured in terms of where the images are stored? I guess it will be on GitHub and not Dockerhub?

[ChristophShyper]

@RafaelWO I have a lot on my plate at work, so barely have any time left for personal projects. But I don't forget about them.

So happy to see you still use it.

I've just added additional option to support .env files to set different credentials for docker repositories and still allow downstream updates to a fork https://github.com/devops-infra/docker-terragrunt?tab=readme-ov-file#forking

It will also ignore missing pair of Docker or Github credentials and only push the configured ones, so you can easily fork it and build images for any combination.

[RafaelWO]

Awesome, thanks a lot @ChristophShyper ! 🙏

I will try forking the project and check if building the images works as expected. Since we use GitLab, I guess I can mirror the repo there and create a CI/CD config similar to .github/workflows/manual-update-version.yml to push images to the Docker registry in the GitLab project.