Infrastructure Folder Structure

Each GitHub repository should follow the same folder structure to hold infrastructure as code sources (Terraform HCL).

Everything should be placed under an infra folder at the root of the repository. This folder should contain multiple Terraform configurations:

• repository: This folder contains the settings for the current GitHub repository, which are managed using Terraform. The suggestion is to use the github-environment-bootstrap module to manage the repository settings.
• bootstrapper: This folder contains the definition of the azure-github-environment-bootstrap (or aws-github-environment-bootstrap) to create:
  • A private GitHub runner, which can be used to perform operations against network-isolated resources.
  • The identities used by the GitHub Actions workflows to perform operations against Azure resources.
  • The GitHub environments containing the information about the target Azure Subscription and identities.
• core: (Optional) This folder contains the definition of the core resources that are shared for the whole subscription, such as the Azure Key Vaults and the Log Analytics Workspace. As the base configuration of the subscription, it is usually only configured once in the central repository of a product (e.g. io-infra as the central repository for the IO product).
• resources: This folder contains the actual definitions of resources organized into modules and environments.

The configurations are specific to an environment and are located in the <env> (es. dev, prod) subfolder. Each configuration can be used for multiple CSP regions.

Configuration Dependencies

The Terraform configurations have specific dependencies that must be respected during deployment:

1. repository → Must be applied first as it sets up the basic GitHub repository settings required by other configurations.

2. core → Should be applied after repository and provides the foundational infrastructure (networking, key vaults, etc.) that other configurations depend on.

3. bootstrapper → Depends on both repository (for GitHub settings) and core (for networking and base resources) configurations. Must be applied after both dependencies are in place.

4. resources

Example

infra/
├─ bootstrapper/
│  ├─ prod/
│  │  ├─ main.tf
│  ├─ dev/
│  │  ├─ main.tf
├─ core/
│  ├─ prod/
│  │  ├─ main.tf
│  ├─ dev/
│  │  ├─ main.tf
├─ repository/
│  ├─ main.tf
├─ resources/
│  ├─ _modules/
│  │  ├─ functions/
│  │  │   ├─ main.tf
│  │  │   ├─ outputs.tf
│  │  │   ├─ inputs.tf
│  │  ├─ resource-groups/
│  │  │   ├─ main.tf
│  │  │   ├─ outputs.tf
│  │  │   ├─ inputs.tf
│  ├─ dev/
│  │  |  ├─ main.tf
│  ├─ prod/
│  │  |  ├─ main.tf