self-hosted-runner: optionally make 'em non-ephemeral

In private repositories, we can often get away with keeping a runner
around, at least as a deallocated VM for most of the time.

Signed-off-by: Johannes Schindelin <[email protected]>

Author: dscho

.github/workflows/create-azure-self-hosted-runners.yml

@@ -27,12 +27,21 @@ on:
         required: true
         description: Deallocate the runner immediately after creating it (useful for spinning up runners preemptively)
         default: "false"
+      ephemeral:
+        type: choice
+        options:
+          - false
+          - true
+        required: true
+        description: Start the runner in ephemeral mode (i.e. unregister after running one job)
+        default: "true"
 
 env:
   ACTIONS_RUNNER_SCOPE: ${{ github.event.inputs.runner_scope }}
   ACTIONS_RUNNER_ORG: "${{ github.event.inputs.runner_org || github.repository_owner }}"
   ACTIONS_RUNNER_REPO: "${{ github.event.inputs.runner_repo || github.event.repository.name }}"
   DEALLOCATE_IMMEDIATELY: ${{ github.event.inputs.deallocate_immediately }}
+  EPHEMERAL_RUNNER: ${{ github.event.inputs.ephemeral }}
   # This has to be a public URL that the VM can access after creation
   POST_DEPLOYMENT_SCRIPT_URL: https://raw.githubusercontent.com/${{ github.repository }}/${{ github.ref }}/azure-self-hosted-runners/post-deployment-script.ps1
   # Note that you'll need "p" (arm64 processor) and ideally "d" (local temp disk). The number 4 stands for 4 CPU-cores.
@@ -142,6 +151,7 @@ jobs:
           publicIpAddressName1="${{ steps.generate-vm-name.outputs.vm_name }}-ip"
           adminUsername="${{ secrets.AZURE_VM_USERNAME }}"
           adminPassword="${{ secrets.AZURE_VM_PASSWORD }}"
+          ephemeral="$EPHEMERAL_RUNNER"
           stopService="$DEALLOCATE_IMMEDIATELY"
           githubActionsRunnerPath="$ACTIONS_RUNNER_PATH"
           location="$AZURE_VM_REGION"

azure-self-hosted-runners/azure-arm-template.json

@@ -36,6 +36,12 @@
                 "description": "Windows Computer Name. Can be maximum 15 characters."
             }
         },
+        "ephemeral": {
+            "type": "string",
+            "metadata": {
+                "description": "(optional) Whether to spin up an ephemeral runner or not."
+            }
+        },
         "stopService": {
             "type": "string",
             "metadata": {
@@ -116,7 +122,7 @@
         "firstFileNameString": "[variables('UriFileNamePieces')[sub(length(variables('UriFileNamePieces')), 1)]]",
         "firstFileNameBreakString": "[split(variables('firstFileNameString'), '?')]",
         "firstFileName": "[variables('firstFileNameBreakString')[0]]",
-        "postDeploymentScriptArguments": "[concat('-GitHubActionsRunnerToken ', parameters('githubActionsRunnerToken'), ' -GithubActionsRunnerRegistrationUrl ', parameters('githubActionsRunnerRegistrationUrl'), ' -GithubActionsRunnerName ', parameters('virtualMachineName'), ' -StopService ', parameters('stopService'), ' -GitHubActionsRunnerPath ', parameters('githubActionsRunnerPath'))]"
+        "postDeploymentScriptArguments": "[concat('-GitHubActionsRunnerToken ', parameters('githubActionsRunnerToken'), ' -GithubActionsRunnerRegistrationUrl ', parameters('githubActionsRunnerRegistrationUrl'), ' -GithubActionsRunnerName ', parameters('virtualMachineName'), ' -Ephemeral ', parameters('ephemeral'), ' -StopService ', parameters('stopService'), ' -GitHubActionsRunnerPath ', parameters('githubActionsRunnerPath'))]"
     },
     "resources": [
         {

azure-self-hosted-runners/post-deployment-script.ps1

@@ -15,6 +15,10 @@ param (
     [ValidateNotNullOrEmpty()]
     [string]$GithubActionsRunnerName,
 
+    [Parameter(Mandatory = $false, HelpMessage = "Start an ephemeral runner (this is the default)")]
+    [ValidateSet('true', 'false')]
+    [string]$Ephemeral = 'true',
+
     [Parameter(Mandatory = $false, HelpMessage = "Stop Service immediately (useful for spinning up runners preemptively)")]
     [ValidateSet('true', 'false')]
     [string]$StopService = 'true',
@@ -261,12 +265,17 @@ Write-Output "Installing GitHub Actions runner $($GitHubAction.Tag) as a Windows
 
 Add-Type -AssemblyName System.IO.Compression.FileSystem ; [System.IO.Compression.ZipFile]::ExtractToDirectory($GitHubAction.OutFile, $GitHubActionsRunnerPath)
 
-Write-Output "Configuring the runner to shut down automatically after running"
-Set-Content -Path "${GitHubActionsRunnerPath}\shut-down.ps1" -Value "shutdown -s -t 60 -d p:4:0 -c `"workflow job is done`""
-[System.Environment]::SetEnvironmentVariable("ACTIONS_RUNNER_HOOK_JOB_COMPLETED", "${GitHubActionsRunnerPath}\shut-down.ps1", [System.EnvironmentVariableTarget]::Machine)
+If ($Ephemeral -ne 'true') {
+    $EphemeralOption = ""
+} Else {
+    $EphemeralOption = "--ephemeral"
+    Write-Output "Configuring the runner to shut down automatically after running"
+    Set-Content -Path "${GitHubActionsRunnerPath}\shut-down.ps1" -Value "shutdown -s -t 60 -d p:4:0 -c `"workflow job is done`""
+    [System.Environment]::SetEnvironmentVariable("ACTIONS_RUNNER_HOOK_JOB_COMPLETED", "${GitHubActionsRunnerPath}\shut-down.ps1", [System.EnvironmentVariableTarget]::Machine)
+}
 
 Write-Output "Configuring the runner"
-cmd.exe /c "${GitHubActionsRunnerPath}\config.cmd" --unattended --ephemeral --name ${GithubActionsRunnerName} --runasservice --labels $($GitHubAction.RunnerLabels) --url ${GithubActionsRunnerRegistrationUrl} --token ${GitHubActionsRunnerToken}
+cmd.exe /c "${GitHubActionsRunnerPath}\config.cmd" --unattended $EphemeralOption --name ${GithubActionsRunnerName} --runasservice --labels $($GitHubAction.RunnerLabels) --url ${GithubActionsRunnerRegistrationUrl} --token ${GitHubActionsRunnerToken}
 
 # Ensure that the service was created. If not, exit with error code.
 if ($null -eq (Get-Service -Name "actions.runner.*")) {