feat!: Automatically select availability zones based on node type when not specified

README.md

@@ -33,6 +33,7 @@ resources that lack official modules.
 | Name | Version |
 |------|---------|
 | <a name="requirement_terraform"></a> [terraform](#requirement\_terraform) | ~> 1.0 |
+| <a name="requirement_azapi"></a> [azapi](#requirement\_azapi) | ~> 1.0 |
 | <a name="requirement_azurerm"></a> [azurerm](#requirement\_azurerm) | ~> 3.17 |
 | <a name="requirement_helm"></a> [helm](#requirement\_helm) | ~> 2.6 |
 | <a name="requirement_kubernetes"></a> [kubernetes](#requirement\_kubernetes) | ~> 2.23 |
@@ -41,6 +42,7 @@ resources that lack official modules.
 
 | Name | Version |
 |------|---------|
+| <a name="provider_azapi"></a> [azapi](#provider\_azapi) | ~> 1.0 |
 | <a name="provider_azurerm"></a> [azurerm](#provider\_azurerm) | ~> 3.17 |
 
 ## Modules
@@ -65,6 +67,7 @@ resources that lack official modules.
 
 | Name | Type |
 |------|------|
+| [azapi_resource_list.az_zones](https://registry.terraform.io/providers/azure/azapi/latest/docs/data-sources/resource_list) | data source |
 | [azurerm_subscription.current](https://registry.terraform.io/providers/hashicorp/azurerm/latest/docs/data-sources/subscription) | data source |
 
 ## Inputs
@@ -97,7 +100,8 @@ resources that lack official modules.
 | <a name="input_location"></a> [location](#input\_location) | n/a | `string` | n/a | yes |
 | <a name="input_namespace"></a> [namespace](#input\_namespace) | String used for prefix resources. | `string` | n/a | yes |
 | <a name="input_node_max_pods"></a> [node\_max\_pods](#input\_node\_max\_pods) | Maximum number of pods per node | `number` | `30` | no |
-| <a name="input_node_pool_zones"></a> [node\_pool\_zones](#input\_node\_pool\_zones) | Availability zones for the node pool | `list(string)` | <pre>[<br>  "1",<br>  "2"<br>]</pre> | no |
+| <a name="input_node_pool_num_zones"></a> [node\_pool\_num\_zones](#input\_node\_pool\_num\_zones) | Number of availability zones to use for the node pool when node\_pool\_zones is not set. | `number` | `2` | no |
+| <a name="input_node_pool_zones"></a> [node\_pool\_zones](#input\_node\_pool\_zones) | Availability zones for the node pool | `list(string)` | `null` | no |
 | <a name="input_oidc_auth_method"></a> [oidc\_auth\_method](#input\_oidc\_auth\_method) | OIDC auth method | `string` | `"implicit"` | no |
 | <a name="input_oidc_client_id"></a> [oidc\_client\_id](#input\_oidc\_client\_id) | The Client ID of application in your identity provider | `string` | `""` | no |
 | <a name="input_oidc_issuer"></a> [oidc\_issuer](#input\_oidc\_issuer) | A url to your Open ID Connect identity provider, i.e. https://cognito-idp.us-east-1.amazonaws.com/us-east-1_uiIFNdacd | `string` | `""` | no |

examples/public-dns/main.tf

@@ -1,8 +1,34 @@
+terraform {
+  required_version = "~> 1.0"
+  required_providers {
+    azurerm = {
+      source  = "hashicorp/azurerm"
+      version = "~> 3.17"
+    }
+    azapi = {
+      source  = "azure/azapi"
+      version = "~> 1.0"
+    }
+    kubernetes = {
+      source  = "hashicorp/kubernetes"
+      version = "~> 2.23"
+    }
+    helm = {
+      source  = "hashicorp/helm"
+      version = "~> 2.6"
+    }
+  }
+}
+
 provider "azurerm" {
   subscription_id = var.subscription_id
   features {}
 }
 
+provider "azapi" {
+  subscription_id = var.subscription_id
+}
+
 data "azurerm_subscription" "current" {}
 
 provider "kubernetes" {
@@ -46,6 +72,7 @@ module "wandb" {
   tags = {
     "Example" : "PublicDns"
   }
+  node_pool_num_zones = 2
 }
 
 # # You'll want to update your DNS with the provisioned IP address

main.tf

@@ -107,6 +107,30 @@ module "app_lb" {
   tags = var.tags
 }
 
+locals {
+  kubernetes_instance_type = try(local.deployment_size[var.size].node_type, var.kubernetes_instance_type)
+}
+
+data "azapi_resource_list" "az_zones" {
+  parent_id = "/subscriptions/${data.azurerm_subscription.current.subscription_id}"
+  type      = "Microsoft.Compute/skus@2021-07-01"
+
+  response_export_values = ["value"]
+}
+
+locals {
+  vm_skus = [
+    for sku in jsondecode(data.azapi_resource_list.az_zones.output).value :
+    sku if(
+      sku.resourceType == "virtualMachines" &&
+      lower(sku.locations[0]) == lower(azurerm_resource_group.default.location) &&
+      sku.name == local.kubernetes_instance_type
+    )
+  ]
+  num_zones       = var.node_pool_zones != null ? length(var.node_pool_zones) : var.node_pool_num_zones
+  node_pool_zones = var.node_pool_zones != null ? var.node_pool_zones : slice(sort(local.vm_skus[0].locationInfo[0].zones), 0, local.num_zones)
+}
+
 module "app_aks" {
   source     = "./modules/app_aks"
   depends_on = [module.app_lb]
@@ -118,8 +142,8 @@ module "app_aks" {
   location              = azurerm_resource_group.default.location
   namespace             = var.namespace
   node_pool_vm_count    = try(local.deployment_size[var.size].node_count, var.kubernetes_node_count)
-  node_pool_vm_size     = try(local.deployment_size[var.size].node_instance, var.kubernetes_instance_type)
-  node_pool_zones       = var.node_pool_zones
+  node_pool_vm_size     = local.kubernetes_instance_type
+  node_pool_zones       = local.node_pool_zones
   public_subnet         = module.networking.public_subnet
   resource_group        = azurerm_resource_group.default
   sku_tier              = var.cluster_sku_tier

variables.tf

@@ -215,7 +215,13 @@ variable "cluster_sku_tier" {
 variable "node_pool_zones" {
   type        = list(string)
   description = "Availability zones for the node pool"
-  default     = ["1", "2"]
+  default     = null
+}
+
+variable "node_pool_num_zones" {
+  type        = number
+  description = "Number of availability zones to use for the node pool when node_pool_zones is not set."
+  default     = 2
 }
 
 variable "node_max_pods" {

versions.tf

@@ -5,6 +5,10 @@ terraform {
       source  = "hashicorp/azurerm"
       version = "~> 3.17"
     }
+    azapi = {
+      source  = "azure/azapi"
+      version = "~> 1.0"
+    }
     kubernetes = {
       source  = "hashicorp/kubernetes"
       version = "~> 2.23"