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-central1-a"
    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
  spot:
    description: Use GCE Spot VM instance; https://cloud.google.com/compute/docs/instances/spot
    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."
  instance_termination_action:
    description: >
      Specifies action that will be taken upon Spot VM preemption or automatic instance termination 
      when the VM's current runtime reaches `max_run_duration`"
    default: DELETE
    required: true
  boot_disk_type:
    description: "Boot disk type for the GCE instance (https://cloud.google.com/sdk/gcloud/reference/compute/disk-types/list)"
    required: false
  max_run_duration:
    description: >
      Limits how long this VM instance can run, specified as a duration relative to the VM instance's most-recent start time."
      Format the duration, as the number of days, hours, minutes, and seconds followed by d, h, m, and s respectively.
      For example, specify 30m for a duration of 30 minutes or specify 1d2h3m4s for a duration of 1 day, 2 hours, 3 minutes, and 4 seconds.
    default: "3d"
    required: true
  org_runner:
    description: >
      Register runner as org wide runner. Main benefit of using org wide runners is that it allows using fine-grained personal access token
      with less privileges compared to repository runners.
    default: true
    required: true
  vm_id_suffix:
    description: Suffix to add to the VM ID. Useful when one job starts multiple runners and they are registered as org wide runners.
    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
      env:
        ACTION_PATH: ${{ github.action_path }}
        INPUT_TOKEN: ${{ inputs.token }}
        INPUT_PROJECT_ID: ${{ inputs.project_id }}
        INPUT_SERVICE_ACCOUNT_KEY: ${{ inputs.service_account_key }}
        INPUT_RUNNER_VER: ${{ inputs.runner_ver }}
        INPUT_MACHINE_ZONE: ${{ inputs.machine_zone }}
        INPUT_MACHINE_TYPE: ${{ inputs.machine_type }}
        INPUT_NETWORK: ${{ inputs.network }}
        INPUT_SUBNET: ${{ inputs.subnet }}
        INPUT_ACCELERATOR: ${{ inputs.accelerator }}
        INPUT_DISK_SIZE: ${{ inputs.disk_size }}
        INPUT_SCOPES: ${{ inputs.scopes }}
        INPUT_SHUTDOWN_TIMEOUT: ${{ inputs.shutdown_timeout }}
        INPUT_RUNNER_SERVICE_ACCOUNT: ${{ inputs.runner_service_account }}
        INPUT_IMAGE_PROJECT: ${{ inputs.image_project }}
        INPUT_IMAGE: ${{ inputs.image }}
        INPUT_IMAGE_FAMILY: ${{ inputs.image_family }}
        INPUT_BOOT_DISK_TYPE: ${{ inputs.boot_disk_type }}
        INPUT_SPOT: ${{ inputs.spot }}
        INPUT_EPHEMERAL: ${{ inputs.ephemeral }}
        INPUT_NO_EXTERNAL_ADDRESS: ${{ inputs.no_external_address }}
        INPUT_ACTIONS_PREINSTALLED: ${{ inputs.actions_preinstalled }}
        INPUT_MAINTENANCE_POLICY_TERMINATE: ${{ inputs.maintenance_policy_terminate }}
        INPUT_INSTANCE_TERMINATION_ACTION: ${{inputs.instance_termination_action}}
        INPUT_ARM: ${{ inputs.arm }}
        INPUT_MAX_RUN_DURATION: ${{inputs.max_run_duration}}
        INPUT_ORG_RUNNER: ${{inputs.org_runner}}
        INPUT_VM_ID_SUFFIX: ${{inputs.vm_id_suffix}}
      run: >
        $ACTION_PATH/action.sh
        --command=start
        --token=$INPUT_TOKEN
        --project_id=$INPUT_PROJECT_ID
        --service_account_key='$INPUT_SERVICE_ACCOUNT_KEY'
        --runner_ver=$INPUT_RUNNER_VER
        --machine_zone=$INPUT_MACHINE_ZONE
        --machine_type=$INPUT_MACHINE_TYPE
        --network=$INPUT_NETWORK
        --subnet=$INPUT_SUBNET
        --accelerator=$INPUT_ACCELERATOR
        --disk_size=$INPUT_DISK_SIZE
        --scopes=$INPUT_SCOPES
        --shutdown_timeout=$INPUT_SHUTDOWN_TIMEOUT
        --runner_service_account=$INPUT_RUNNER_SERVICE_ACCOUNT
        --image_project=$INPUT_IMAGE_PROJECT
        --image=$INPUT_IMAGE
        --image_family=$INPUT_IMAGE_FAMILY
        --boot_disk_type=$INPUT_BOOT_DISK_TYPE
        --spot=$INPUT_SPOT
        --ephemeral=$INPUT_EPHEMERAL
        --no_external_address=$INPUT_NO_EXTERNAL_ADDRESS
        --actions_preinstalled=$INPUT_ACTIONS_PREINSTALLED
        --maintenance_policy_terminate=$INPUT_MAINTENANCE_POLICY_TERMINATE
        --instance_termination_action=$INPUT_INSTANCE_TERMINATION_ACTION
        --arm=$INPUT_ARM
        --max_run_duration=$INPUT_MAX_RUN_DURATION
        --org_runner=$INPUT_ORG_RUNNER
        --vm_id_suffix=$INPUT_VM_ID_SUFFIX
      shell: bash