feat: Support spot VM instance (#203)

Author: t-miyak

modules/gh-runner-gke/README.md

@@ -102,6 +102,7 @@ This example shows how to deploy Self Hosted Runners on GKE that supports Docker
 | project\_id | The project id to deploy Github Runner cluster | `string` | n/a | yes |
 | region | The GCP region to deploy instances into | `string` | `"us-east4"` | no |
 | service\_account | Optional Service Account for the nodes | `string` | `""` | no |
+| spot | A boolean that represents whether the underlying node VMs are spot | `bool` | `false` | no |
 | subnet\_ip | IP range for the subnet | `string` | `"10.0.0.0/17"` | no |
 | subnet\_name | Name for the subnet | `string` | `"runner-subnet"` | no |
 | subnetwork\_project | The ID of the project in which the subnetwork belongs. If it is not provided, the project\_id is used. | `string` | `""` | no |

modules/gh-runner-gke/main.tf

@@ -76,6 +76,7 @@ module "runner-cluster" {
       auto_upgrade         = true
       machine_type         = var.machine_type
       enable_private_nodes = var.enable_private_nodes
+      spot                 = var.spot
     }
   ]
 }

modules/gh-runner-gke/variables.tf

@@ -189,3 +189,9 @@ variable "enable_private_nodes" {
   description = "Whether nodes have internal IP addresses only."
   default     = false
 }
+
+variable "spot" {
+  type        = bool
+  description = "A boolean that represents whether the underlying node VMs are spot"
+  default     = false
+}

modules/gh-runner-mig-container-vm/README.md

@@ -41,6 +41,8 @@ This example shows how to deploy a Self Hosted Runner on MIG Container VMs.
 | repo\_url | Repo URL for the Github Action | `string` | n/a | yes |
 | restart\_policy | The desired Docker restart policy for the runner image | `string` | `"Always"` | no |
 | service\_account | Service account email address | `string` | `""` | no |
+| spot | Provision a SPOT instance | `bool` | `false` | no |
+| spot\_instance\_termination\_action | Action to take when Compute Engine preempts a Spot VM. | `string` | `"STOP"` | no |
 | subnet\_ip | IP range for the subnet | `string` | `"10.10.10.0/24"` | no |
 | subnet\_name | Name for the subnet | `string` | `"gh-runner-subnet"` | no |
 | subnetwork\_project | The ID of the project in which the subnetwork belongs. If it is not provided, the project\_id is used. | `string` | `""` | no |

modules/gh-runner-mig-container-vm/main.tf

@@ -163,15 +163,17 @@ module "mig_template" {
       "https://www.googleapis.com/auth/cloud-platform",
     ]
   }
-  disk_size_gb         = 100
-  disk_type            = "pd-ssd"
-  auto_delete          = true
-  name_prefix          = "gh-runner"
-  source_image_family  = "cos-stable"
-  source_image_project = "cos-cloud"
-  startup_script       = "export TEST_ENV='hello'"
-  source_image         = reverse(split("/", module.gce-container.source_image))[0]
-  metadata             = merge(var.additional_metadata, { "gce-container-declaration" = module.gce-container.metadata_value })
+  disk_size_gb                     = 100
+  disk_type                        = "pd-ssd"
+  auto_delete                      = true
+  name_prefix                      = "gh-runner"
+  source_image_family              = "cos-stable"
+  source_image_project             = "cos-cloud"
+  startup_script                   = "export TEST_ENV='hello'"
+  source_image                     = reverse(split("/", module.gce-container.source_image))[0]
+  spot                             = var.spot
+  spot_instance_termination_action = var.spot_instance_termination_action
+  metadata                         = merge(var.additional_metadata, { "gce-container-declaration" = module.gce-container.metadata_value })
   tags = [
     "gh-runner-vm"
   ]

modules/gh-runner-mig-container-vm/variables.tf

@@ -119,3 +119,15 @@ variable "cooldown_period" {
   type        = number
   default     = 60
 }
+
+variable "spot" {
+  type        = bool
+  description = "Provision a SPOT instance"
+  default     = false
+}
+
+variable "spot_instance_termination_action" {
+  description = "Action to take when Compute Engine preempts a Spot VM."
+  type        = string
+  default     = "STOP"
+}

modules/gh-runner-mig-vm/README.md

@@ -48,6 +48,8 @@ This example shows how to deploy a MIG Self Hosted Runner with an image pre-bake
 | source\_image | Source disk image. If neither source\_image nor source\_image\_family is specified, defaults to the latest public CentOS image. | `string` | `""` | no |
 | source\_image\_family | Source image family. If neither source\_image nor source\_image\_family is specified, defaults to the latest public Ubuntu image. | `string` | `"ubuntu-1804-lts"` | no |
 | source\_image\_project | Project where the source image comes from | `string` | `"ubuntu-os-cloud"` | no |
+| spot | Provision a SPOT instance | `bool` | `false` | no |
+| spot\_instance\_termination\_action | Action to take when Compute Engine preempts a Spot VM. | `string` | `"STOP"` | no |
 | startup\_script | User startup script to run when instances spin up | `string` | `""` | no |
 | subnet\_ip | IP range for the subnet | `string` | `"10.10.10.0/24"` | no |
 | subnet\_name | Name for the subnet | `string` | `"gh-runner-subnet"` | no |

modules/gh-runner-mig-vm/main.tf

@@ -132,14 +132,16 @@ module "mig_template" {
       "https://www.googleapis.com/auth/cloud-platform",
     ]
   }
-  disk_size_gb         = 100
-  disk_type            = "pd-ssd"
-  auto_delete          = true
-  name_prefix          = "gh-runner"
-  source_image_family  = var.source_image_family
-  source_image_project = var.source_image_project
-  startup_script       = local.startup_script
-  source_image         = var.source_image
+  disk_size_gb                     = 100
+  disk_type                        = "pd-ssd"
+  auto_delete                      = true
+  name_prefix                      = "gh-runner"
+  source_image_family              = var.source_image_family
+  source_image_project             = var.source_image_project
+  startup_script                   = local.startup_script
+  source_image                     = var.source_image
+  spot                             = var.spot
+  spot_instance_termination_action = var.spot_instance_termination_action
   metadata = merge({
     "secret-id" = google_secret_manager_secret_version.gh-secret-version.name
     }, {

modules/gh-runner-mig-vm/variables.tf

@@ -153,3 +153,15 @@ variable "instance_tags" {
   description = "Additional tags to add to the instances"
   default     = []
 }
+
+variable "spot" {
+  type        = bool
+  description = "Provision a SPOT instance"
+  default     = false
+}
+
+variable "spot_instance_termination_action" {
+  description = "Action to take when Compute Engine preempts a Spot VM."
+  type        = string
+  default     = "STOP"
+}