Terraform modules

Shared modules used by various DfE services.

Modules

• aks/application
• aks/application_configuration
• aks/cluster_data
• aks/dfe_analytics
• aks/postgres
• aks/redis
• aks/secrets
• dns/records
• dns/zones
• domains/environment_domains
• domains/infrastructure
• monitoring/statuscake

Example deployment

The Example Rails deployment document outlines the minimum steps required to set up a Rails application deployed using AKS.

Release Process

Git References

We use three git references to manage and promote new features:

main branch

All new features are added here first. This branch is used in environments with the lowest risk, such as review apps, to quickly test new features, catch errors early, and minimise the impact of bugs.

testing tag

A pre-release is generated every week that includes any new features in main from the past week. This tag is automatically updated and used in low-risk environments like development or QA. This allows us to catch errors in production-like environments and keep the impact of bugs low.

stable tag

A release is created that includes the features which were in the testing phase the previous week. This tag is automatically updated and used in higher-risk environments like production or preproduction. This ensures that only thoroughly tested features are deployed.

Promotion Process

Let's assume the stable tag points to v0.x.0 and testing points to v0.y.0. You can view the tags and their commit IDs in the tags list.

To promote testing to stable:

1. Delete the current pre-release pointing to v0.y.0
2. Create a new release:
   • Select Draft new release
   • Click Choose a tag and enter v0.y.0
   • Select Previous tag v0.x.0
   • Click Generate release notes
   • Check the Set as the latest release box
   • Click Publish release

To promote new commits in main to testing:

If there are new commits in main that you want to promote to testing, increment v0.y.0 to v0.z.0, then create a new pre-release:

1. Select Draft new release
2. Click Choose a tag and enter v0.z.0
3. Click Create new tag
4. Select the Previous tag v0.y.0
5. Click Generate release notes
6. Check the Set as a pre-release box
7. Click Publish release

Updating Terraform Docs

Terraform Docs can be used in two ways:

Install

• Install Terraform Docs according to the instructions for your platform.
• Run terraform-docs [module] for each module, where module is the path, for example:

  $ terraform-docs aks/application

Run as a Docker container

• Run the following command in each module directory where the docs need to be updated:

docker run --rm --volume "$(pwd):/terraform-docs" -u $(id -u) quay.io/terraform-docs/terraform-docs:0.16.0 markdown /terraform-docs > tfdocs.md