This repository contains workflows for idempotantly creating & updating Actions Runner Controller (ARC) scale sets for GitHub self-hosted runners. This uses the open source ARC for GitHub and Azure Kubernetes Service. Additionally, Azure Container Registry can be used to provide a custom container image for runners.
Future updates planned:
- Hashing & caching of scale-set value files to determine if configuration has changed and requires a
helm upgradeor not (to prevent tear-down & rebuild every workflow execution)
- Azure Kubernetes Cluster (AKS)
- Azure Container Registry (ACR) and
- Azure Service Principal connection information
- GitHub App installed on organizations, or a PAT with appropriate access (see documentation)
- GitHub Apps are preferred over PAT because of the higher API rate limit and lack of tie-back to user identities, but can't be used with enterprise level runners.
| secret key | description |
|---|---|
| APP_ID | GitHub App ID |
| APP_INSTALL_ID | GitHub App Installation ID (different for each org) |
| APP_PRIVATE_KEY | The private key file (.pem) created for the app |
| AZURE_CLIENT_ID | Azure Service Principal Client ID |
| AZURE_CLIENT_SECRET | Azure Service Principal Client Secret |
| AZURE_SUBSCRIPTION_ID | Azure Service Principal Subscription ID |
| AZURE_TENANT_ID | Azure Service Principal Tenant ID |
| CUSTOM_PAT | A custom GitHub Personal Access Token to use when NOT using the GitHub App (required for enterprise level runners) |
| REGISTRY_LOGIN_SERVER | ACR registry host name |
- Complete Prerequisites
- Move all GitHub Actions YAML files in
./workflowsto./.github/workflows(I have them here so that my repo doesn't attempt to run them) - Run
controller.yamlto make sure the ARC controller is present - Modify
./.github/workflows/scale-sets.yamlto fit your needs, and be sure to add the corresponding values config YAML file overrides to the./scale-sets/directory (two included). - If using a custom image in ACR, make sure to update & run your
./Dockerfileand/customer-runner-image.yamlworkflow accordingly. Additionally, any values override files that use the image will need the corrected values (see./scale-sets/enterprise.yamlfor example).