action.yml

name: "Ephemeral GCE GitHub self-hosted runner"
description: >-
  Creates ephemeral GCE based GitHub Action self-hosted runner.
  It uses startup script to bootstrap the VM.
author: Rafal Wojdyla
branding:
  icon: triangle
  color: purple
inputs:
  token:
    description: >-
      GitHub auth token, needs `repo`/`public_repo` scope: https://docs.github.com/en/rest/reference/actions#self-hosted-runners.
    required: true
  project_id:
    description: >-
      ID of the Google Cloud Platform project. If provided, this will configure gcloud to use this project ID.
    required: false
  service_account_key:
    description: >-
      The service account key which will be used for authentication credentials.
      This key should be created and stored as a secret. Should be JSON key.
    required: false
  runner_ver:
    description: Version of the GitHub Runner. "latest" will resolve the latest version.
    default: "latest"
    required: true
  machine_zone:
    description: GCE zone
    default: "us-east1-c"
    required: true
  machine_type:
    description: GCE machine type; https://cloud.google.com/compute/docs/machine-types
    default: "n1-standard-4"
    required: true
  disk_size:
    description: VM disk size.
    required: false
  network:
    description: Specifies the network that the VM instances are a part of.
    required: false
  subnet:
    description: Specifies the subnet that the VM instances are a part of (must be part of network).
    required: false
  accelerator:
    description: >
      [count=COUNT],[type=TYPE]
        Attaches accelerators (e.g. GPUs) to the instances.
        TYPE
        The specific type (e.g. nvidia-tesla-k80 for nVidia Tesla K80) of accelerator 
        to attach to the instances. Use 'gcloud compute accelerator-types list' to 
        learn about all available accelerator types.
        COUNT
        Number of accelerators to attach to each instance. The default value is 1.
    required: false
  runner_service_account:
    description: Service account of the VM, defaults to default compute service account.
    required: false
  image_project:
    description: >
      The Google Cloud project against which all image and image family
      references will be resolved.
    required: false
  image:
    description: Specifies the name of the image that the disk will be initialized with.
    required: false
  image_family:
    description: The image family for the operating system that the boot disk will be initialized with.
    required: false
  preemptible:
    description: Use GCE preemptible VM instance; https://cloud.google.com/compute/docs/instances/preemptible
    default: false
    required: true
  ephemeral:
    description: Set GitHub runner to be ephemeral; https://docs.github.com/en/actions/hosting-your-own-runners/autoscaling-with-self-hosted-runners#using-ephemeral-runners-for-autoscaling
    default: false
    required: true
  no_external_address:
    description: Disables external IP address for the worker
    default: false
    required: true
  scopes:
    description: Scopes granted to the VM, defaults to full access (cloud-platform).
    default: cloud-platform
    required: true
  shutdown_timeout:
    description: "Shutdown grace period (in seconds)."
    default: 30
    required: true
  actions_preinstalled:
    description: "Whether the GitHub actions have already been installed at `/actions-runner`."
    default: false
    required: true
  arm:
    description: "Whether the GitHub actions should use arm64 binaries."
    default: false
    required: false
  maintenance_policy_terminate:
    description: "Set Google maintenance policy to TERMINATE.  This is required for GPUs as they do ot support live-migration."
  boot_disk_type:
    description: "Boot disk type for the GCE instance (https://cloud.google.com/sdk/gcloud/reference/compute/disk-types/list)"
    required: false
outputs:
  label:
    description: >-
      Unique runner label. This label can be used to request a specific
      runner for the workflow job.
    value: ${{ steps.gce-github-runner-script.outputs.label }}
runs:
  using: "composite"
  steps:
    - id: gce-github-runner-script
      run: >
        ${{ github.action_path }}/action.sh
        --command=start
        --token=${{ inputs.token }}
        --project_id=${{ inputs.project_id }}
        --service_account_key='${{ inputs.service_account_key }}'
        --runner_ver=${{ inputs.runner_ver }}
        --machine_zone=${{ inputs.machine_zone }}
        --machine_type=${{ inputs.machine_type }}
        --network=${{ inputs.network }}
        --subnet=${{ inputs.subnet }}
        --accelerator=${{ inputs.accelerator }}
        --disk_size=${{ inputs.disk_size }}
        --scopes=${{ inputs.scopes }}
        --shutdown_timeout=${{ inputs.shutdown_timeout }}
        --runner_service_account=${{ inputs.runner_service_account }}
        --image_project=${{ inputs.image_project }}
        --image=${{ inputs.image }}
        --image_family=${{ inputs.image_family }}
        --boot_disk_type=${{ inputs.boot_disk_type }}
        --preemptible=${{ inputs.preemptible }}
        --ephemeral=${{ inputs.ephemeral }}
        --no_external_address=${{ inputs.no_external_address }}
        --actions_preinstalled=${{ inputs.actions_preinstalled }}
        --maintenance_policy_terminate=${{ inputs.maintenance_policy_terminate }}
        --arm=${{ inputs.arm }}
      shell: bash