feat: Add Autoscaling schedule for EKS managed node group (#2504)

Co-authored-by: Bryant Biggs <bryantbiggs@gmail.com>

examples/eks_managed_node_group/main.tf

@@ -264,6 +264,27 @@ module "eks" {
         additional                         = aws_iam_policy.node_additional.arn
       }
 
+      schedules = {
+        scale-up = {
+          min_size     = 2
+          max_size     = "-1" # Retains current max size
+          desired_size = 2
+          start_time   = "2023-03-05T00:00:00Z"
+          end_time     = "2024-03-05T00:00:00Z"
+          timezone     = "Etc/GMT+0"
+          recurrence   = "0 0 * * *"
+        },
+        scale-down = {
+          min_size     = 0
+          max_size     = "-1" # Retains current max size
+          desired_size = 0
+          start_time   = "2023-03-05T12:00:00Z"
+          end_time     = "2024-03-05T12:00:00Z"
+          timezone     = "Etc/GMT+0"
+          recurrence   = "0 12 * * *"
+        }
+      }
+
       tags = {
         ExtraTag = "EKS managed node group complete example"
       }

modules/eks-managed-node-group/README.md

@@ -82,6 +82,7 @@ module "eks_managed_node_group" {
 
 | Name | Type |
 |------|------|
+| [aws_autoscaling_schedule.this](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/autoscaling_schedule) | resource |
 | [aws_eks_node_group.this](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/eks_node_group) | resource |
 | [aws_iam_role.this](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/iam_role) | resource |
 | [aws_iam_role_policy_attachment.additional](https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/iam_role_policy_attachment) | resource |
@@ -113,6 +114,7 @@ module "eks_managed_node_group" {
 | <a name="input_create"></a> [create](#input\_create) | Determines whether to create EKS managed node group or not | `bool` | `true` | no |
 | <a name="input_create_iam_role"></a> [create\_iam\_role](#input\_create\_iam\_role) | Determines whether an IAM role is created or to use an existing IAM role | `bool` | `true` | no |
 | <a name="input_create_launch_template"></a> [create\_launch\_template](#input\_create\_launch\_template) | Determines whether to create a launch template or not. If set to `false`, EKS will use its own default launch template | `bool` | `true` | no |
+| <a name="input_create_schedule"></a> [create\_schedule](#input\_create\_schedule) | Determines whether to create autoscaling group schedule or not | `bool` | `true` | no |
 | <a name="input_credit_specification"></a> [credit\_specification](#input\_credit\_specification) | Customize the credit specification of the instance | `map(string)` | `{}` | no |
 | <a name="input_desired_size"></a> [desired\_size](#input\_desired\_size) | Desired number of instances/nodes | `number` | `1` | no |
 | <a name="input_disable_api_termination"></a> [disable\_api\_termination](#input\_disable\_api\_termination) | If true, enables EC2 instance termination protection | `bool` | `null` | no |
@@ -159,6 +161,7 @@ module "eks_managed_node_group" {
 | <a name="input_private_dns_name_options"></a> [private\_dns\_name\_options](#input\_private\_dns\_name\_options) | The options for the instance hostname. The default values are inherited from the subnet | `map(string)` | `{}` | no |
 | <a name="input_ram_disk_id"></a> [ram\_disk\_id](#input\_ram\_disk\_id) | The ID of the ram disk | `string` | `null` | no |
 | <a name="input_remote_access"></a> [remote\_access](#input\_remote\_access) | Configuration block with remote access settings. Only valid when `use_custom_launch_template` = `false` | `any` | `{}` | no |
+| <a name="input_schedules"></a> [schedules](#input\_schedules) | Map of autoscaling group schedule to create | `map(any)` | `{}` | no |
 | <a name="input_subnet_ids"></a> [subnet\_ids](#input\_subnet\_ids) | Identifiers of EC2 Subnets to associate with the EKS Node Group. These subnets must have the following resource tag: `kubernetes.io/cluster/CLUSTER_NAME` | `list(string)` | `null` | no |
 | <a name="input_tag_specifications"></a> [tag\_specifications](#input\_tag\_specifications) | The tags to apply to the resources during launch | `list(string)` | <pre>[<br>  "instance",<br>  "volume",<br>  "network-interface"<br>]</pre> | no |
 | <a name="input_tags"></a> [tags](#input\_tags) | A map of tags to add to all resources | `map(string)` | `{}` | no |
@@ -175,6 +178,7 @@ module "eks_managed_node_group" {
 
 | Name | Description |
 |------|-------------|
+| <a name="output_autoscaling_group_schedule_arns"></a> [autoscaling\_group\_schedule\_arns](#output\_autoscaling\_group\_schedule\_arns) | ARNs of autoscaling group schedules |
 | <a name="output_iam_role_arn"></a> [iam\_role\_arn](#output\_iam\_role\_arn) | The Amazon Resource Name (ARN) specifying the IAM role |
 | <a name="output_iam_role_name"></a> [iam\_role\_name](#output\_iam\_role\_name) | The name of the IAM role |
 | <a name="output_iam_role_unique_id"></a> [iam\_role\_unique\_id](#output\_iam\_role\_unique\_id) | Stable and unique string identifying the IAM role |

modules/eks-managed-node-group/main.tf

@@ -447,3 +447,25 @@ resource "aws_iam_role_policy_attachment" "additional" {
   policy_arn = each.value
   role       = aws_iam_role.this[0].name
 }
+
+################################################################################
+# Autoscaling Group Schedule
+################################################################################
+
+resource "aws_autoscaling_schedule" "this" {
+  for_each = { for k, v in var.schedules : k => v if var.create && var.create_schedule }
+
+  scheduled_action_name  = each.key
+  autoscaling_group_name = aws_eks_node_group.this[0].resources[0].autoscaling_groups[0].name
+
+  min_size         = try(each.value.min_size, null)
+  max_size         = try(each.value.max_size, null)
+  desired_capacity = try(each.value.desired_size, null)
+  start_time       = try(each.value.start_time, null)
+  end_time         = try(each.value.end_time, null)
+  time_zone        = try(each.value.time_zone, null)
+
+  # [Minute] [Hour] [Day_of_Month] [Month_of_Year] [Day_of_Week]
+  # Cron examples: https://crontab.guru/examples.html
+  recurrence = try(each.value.recurrence, null)
+}

modules/eks-managed-node-group/outputs.tf

@@ -61,6 +61,15 @@ output "node_group_taints" {
   value       = try(aws_eks_node_group.this[0].taint, [])
 }
 
+################################################################################
+# Autoscaling Group Schedule
+################################################################################
+
+output "autoscaling_group_schedule_arns" {
+  description = "ARNs of autoscaling group schedules"
+  value       = { for k, v in aws_autoscaling_schedule.this : k => v.arn }
+}
+
 ################################################################################
 # IAM Role
 ################################################################################

modules/eks-managed-node-group/variables.tf

@@ -469,3 +469,19 @@ variable "iam_role_tags" {
   type        = map(string)
   default     = {}
 }
+
+################################################################################
+# Autoscaling Group Schedule
+################################################################################
+
+variable "create_schedule" {
+  description = "Determines whether to create autoscaling group schedule or not"
+  type        = bool
+  default     = true
+}
+
+variable "schedules" {
+  description = "Map of autoscaling group schedule to create"
+  type        = map(any)
+  default     = {}
+}

modules/self-managed-node-group/main.tf

@@ -680,7 +680,7 @@ resource "aws_autoscaling_group" "this" {
 ################################################################################
 
 resource "aws_autoscaling_schedule" "this" {
-  for_each = var.create && var.create_schedule ? var.schedules : {}
+  for_each = { for k, v in var.schedules : k => v if var.create && var.create_schedule }
 
   scheduled_action_name  = each.key
   autoscaling_group_name = aws_autoscaling_group.this[0].name

modules/self-managed-node-group/outputs.tf

@@ -82,7 +82,7 @@ output "autoscaling_group_vpc_zone_identifier" {
 }
 
 ################################################################################
-# autoscaling group schedule
+# Autoscaling Group Schedule
 ################################################################################
 
 output "autoscaling_group_schedule_arns" {

node_groups.tf

@@ -363,6 +363,9 @@ module "eks_managed_node_group" {
   # https://github.com/hashicorp/terraform/issues/31646#issuecomment-1217279031
   iam_role_additional_policies = lookup(each.value, "iam_role_additional_policies", lookup(var.eks_managed_node_group_defaults, "iam_role_additional_policies", {}))
 
+  create_schedule = try(each.value.create_schedule, var.eks_managed_node_group_defaults.create_schedule, true)
+  schedules       = try(each.value.schedules, var.eks_managed_node_group_defaults.schedules, {})
+
   # Security group
   vpc_security_group_ids            = compact(concat([local.node_security_group_id], try(each.value.vpc_security_group_ids, var.eks_managed_node_group_defaults.vpc_security_group_ids, [])))
   cluster_primary_security_group_id = try(each.value.attach_cluster_primary_security_group, var.eks_managed_node_group_defaults.attach_cluster_primary_security_group, false) ? aws_eks_cluster.this[0].vpc_config[0].cluster_security_group_id : null
@@ -426,7 +429,7 @@ module "self_managed_node_group" {
   mixed_instances_policy     = try(each.value.mixed_instances_policy, var.self_managed_node_group_defaults.mixed_instances_policy, null)
   warm_pool                  = try(each.value.warm_pool, var.self_managed_node_group_defaults.warm_pool, {})
 
-  create_schedule = try(each.value.create_schedule, var.self_managed_node_group_defaults.create_schedule, false)
+  create_schedule = try(each.value.create_schedule, var.self_managed_node_group_defaults.create_schedule, true)
   schedules       = try(each.value.schedules, var.self_managed_node_group_defaults.schedules, {})
 
   delete_timeout         = try(each.value.delete_timeout, var.self_managed_node_group_defaults.delete_timeout, null)