Terraform GitHub Actions Runner Controller (ARC) Module

This Terraform module deploys the GitHub Actions Runner Controller on a Kubernetes cluster, including all necessary dependencies.

Features

• Deploys cert-manager as a dependency
• Configures GitHub token authentication
• Supports custom runner deployments with optional autoscaling
• Cross-architecture support (amd64/arm64)
• Customizable namespace and configuration

Usage

# Configure providers in your root module
provider "kubernetes" {
  config_path    = "~/.kube/config"
  config_context = "my-context"
}

provider "helm" {
  kubernetes {
    config_path    = "~/.kube/config"
    config_context = "my-context"
  }
}

module "arc" {
  source = "github.com/idvoretskyi/Terraform-ARC-cluster"
  
  github_token = "ghp_your_github_token"
  
  # Optional: Configure runner deployments
  runner_deployments = [
    {
      name       = "runner-deployment"
      repository = "my-org/my-repo"
      replicas   = 2
      labels     = ["self-hosted", "linux", "x64"]
      env = [
        {
          name  = "RUNNER_WORKDIR"
          value = "/home/runner/work"
        }
      ]
      resources = {
        limits = {
          cpu    = "500m"
          memory = "512Mi"
        }
        requests = {
          cpu    = "250m"
          memory = "256Mi"
        }
      }
    }
  ]
  
  # Optional: Configure autoscaling
  runner_autoscalers = [
    {
      name              = "runner-autoscaler"
      target_deployment = "runner-deployment"
      min_replicas      = 1
      max_replicas      = 5
      metrics = [
        {
          type = "TotalNumberOfQueuedAndInProgressWorkflowRuns"
          repositoryNames = ["my-org/my-repo"]
          scaleUpThreshold = "1"
          scaleDownThreshold = "0"
          scaleUpFactor = "2"
          scaleDownFactor = "0.5"
        }
      ]
    }
  ]
}

Requirements

Name	Version
terraform	>= 1.0.0
kubernetes	>= 2.0.0
helm	>= 2.0.0

Providers

Name	Version
kubernetes	>= 2.0.0
helm	>= 2.0.0

Inputs

Name	Description	Type	Default	Required
github_token	GitHub Personal Access Token with appropriate permissions	string	n/a	yes
namespace	Kubernetes namespace for Actions Runner Controller	string	"arc-system"	no
create_namespace	Whether to create a new namespace for ARC	bool	true	no
helm_chart_version	Version of the ARC Helm chart	string	"0.23.5"	no
helm_values	Additional Helm values for ARC chart (in YAML format)	string	""	no
cert_manager_version	Version of cert-manager Helm chart	string	"v1.12.0"	no
cert_manager_values	Values for cert-manager Helm chart	string	""	no
add_arch_tolerations	Whether to add architecture-specific tolerations to pods	bool	false	no
node_architecture	Node architecture (amd64 or arm64)	string	"amd64"	no
runner_deployments	List of runner deployment configurations	list(object)	[]	no
runner_autoscalers	List of runner autoscaler configurations	list(object)	[]	no

Outputs

Name	Description
namespace	The Kubernetes namespace where ARC was deployed
cert_manager_release_name	The name of the cert-manager Helm release
arc_release_name	The name of the Actions Runner Controller Helm release
runner_deployments	The deployed runner deployments
runner_autoscalers	The deployed runner autoscalers

License

This module is licensed under the Apache License, Version 2.0. See LICENSE for the full license text.

Author

Ihor Dvoretskyi