Plan:

• Find the terraform modules in the repository.
• Ensure each terraform module is following the implementation standards.
• Run the tests to ensure the modules work as expected.

Implementation standards

• Expected versions:

  • terraform: ~> 1.12
  • juju provider: ~> 1.0

• The module should only have a "model_uuid" variable, no "model" variable.

• Lint terraform modules with terraform fmt --recursive and tflint --recursive (fix the errors and the warnings).

Testing

Writing terraform tests

• The terraform/tests folder should look like: https://github.com/canonical/platform-engineering-charm-template/tree/main/terraform/tests

  • There is a setup folder to configure the model. Follow the example from https://raw.githubusercontent.com/canonical/platform-engineering-charm-template/refs/heads/main/terraform/tests/setup/main.tf

  • There is main.tftest.hcl file. Follow the example of https://raw.githubusercontent.com/canonical/platform-engineering-charm-template/refs/heads/main/terraform/tests/main.tftest.hcl

    • Ensure that there is a renovate directive above each "revision" line.

  • After adapting the tests. There should not be a terraform/tests/main.tf file.

Local testing

The terraform tests should be run in a virtual machine named "charmkeeper".

If the machine doesn't exist, create it with: scripts/create-charmkeeper-vm.sh.

If not already done, mount the working directory folder in the machine with

multipass mount --type native $PWD charmkeeper:/workdir

For each TERRAFORM_MODULE

multipass exec charmkeeper -d /workdir/$TERRAFORM_MODULE -- terraform init
multipass exec charmkeeper -d /workdir/$TERRAFORM_MODULE -- terraform test

CI testing

This workflow is the reference to use to implement or update CI tests: https://raw.githubusercontent.com/canonical/platform-engineering-charm-template/refs/heads/main/.github/workflows/test_terraform_modules.yaml

• Adapt the k8s-controller and lxd-controller value depending on the charm type.
• Adapt the terraform-directories to reflect where the modules are in this charm.

Maintain

Configuring renovate

Configure renovate like https://raw.githubusercontent.com/canonical/platform-engineering-charm-template/refs/heads/main/renovate.json to

• Add a charmhub datasource and use it.
• Add a regex custom manager for revisions.
• Set ignorePath to an empty array to not exclude the tests/ folders of terraform.