Document known-compatible Terraform versions(s)

[jalessio]

It would be great to include a list of known-compatible / recommended versions of Terraform in the top-level README. I have come across a number of issues (myself included) that appear stem from folks using a newer version of Terraform than what Stack was developed against / supports.

Examples:

• subnet_ids expect string but is list #59 - subnet_ids expect string but is list
• Stack and Terraform v0.7.0 #39 - Stack and Terraform v0.7.0
• Resource count can't reference module variable (Question) #57 - Resource count can't reference module variable (Question)

I see a comment from 7/27/2016 that indicates the stack team is using v0.6.15. Is this still valid? If not, what's the current recommended version of Terraform to use?

[achille-roussel]

We're using TF 0.8 here so it's definitely working with newer versions. It's a good point tho, we should document this (although considering how fast hashicorp releases TF versions this is likely going to be out-of-sync very often).

[jalessio]

@achille-roussel which minor version of TF 0.8 are you using? I'll add it to the README and submit a PR. Here's the terraform CHANGELOG.md which lists all the versions:
https://github.com/hashicorp/terraform/blob/v0.8.7/CHANGELOG.md

[jalessio]

Wait, just noticed that you do specify a terraform version in the Dockerfile so I suppose the docs should match that version:

RUN curl -sL "https://releases.hashicorp.com/terraform/0.7.2/terraform_0.7.2_linux_amd64.zip"> terraform.zip \
  && unzip terraform.zip \
  && mv terraform /usr/local/bin

[achille-roussel]

This could very well be updated, we don't use this container here it was added as a contribution by someone from the community.

We're using the latest TF version (0.8.7).