refactor: Enhance node pool validation for priority, eviction policy, and spot max price

Author: tblakex01

modules/aks/main.tf

@@ -92,6 +92,15 @@ resource "azurerm_kubernetes_cluster" "aks" {
   tags = var.tags
 }
 
+locals {
+  # Create a map with spot instance flags for each node pool
+  node_pool_configs = {
+    for k, v in var.node_pools : k => {
+      is_spot = lower(v.priority) == "spot"
+    }
+  }
+}
+
 resource "azurerm_kubernetes_cluster_node_pool" "additional" {
   for_each = var.node_pools
 
@@ -120,9 +129,9 @@ resource "azurerm_kubernetes_cluster_node_pool" "additional" {
   ]
 
   # Normalize to the capitalized form expected by the provider
-  priority        = lower(each.value.priority) == "spot" ? "Spot" : "Regular"
-  eviction_policy = lower(each.value.priority) == "spot" ? each.value.eviction_policy : null
-  spot_max_price  = lower(each.value.priority) == "spot" ? each.value.spot_max_price : null
+  priority        = local.node_pool_configs[each.key].is_spot ? "Spot" : "Regular"
+  eviction_policy = local.node_pool_configs[each.key].is_spot ? title(lower(each.value.eviction_policy)) : null
+  spot_max_price  = local.node_pool_configs[each.key].is_spot ? each.value.spot_max_price : null
 
   tags = merge(var.tags, each.value.tags)
 
@@ -132,7 +141,7 @@ resource "azurerm_kubernetes_cluster_node_pool" "additional" {
       error_message = "Node pool '${each.key}' has invalid priority '${each.value.priority}'. Priority must be either 'Regular' or 'Spot' (case-insensitive)."
     }
     precondition {
-      condition     = lower(each.value.priority) != "spot" || contains(["delete", "deallocate"], lower(each.value.eviction_policy))
+      condition     = !local.node_pool_configs[each.key].is_spot || contains(["delete", "deallocate"], lower(each.value.eviction_policy))
       error_message = "Node pool '${each.key}' has invalid eviction_policy '${each.value.eviction_policy}'. When priority is 'Spot', eviction_policy must be either 'Delete' or 'Deallocate' (case-insensitive)."
     }
     precondition {

modules/aks/variables.tf

@@ -88,6 +88,28 @@ variable "node_pools" {
     spot_max_price  = optional(number, -1)        # Max price for Spot instances (must be >= -1), -1 uses market price
   }))
   default = {}
+
+  validation {
+    condition = alltrue([
+      for k, v in var.node_pools : contains(["regular", "spot"], lower(v.priority))
+    ])
+    error_message = "Each node pool's priority must be either 'Regular' or 'Spot' (case-insensitive)."
+  }
+
+  validation {
+    condition = alltrue([
+      for k, v in var.node_pools :
+      lower(v.priority) != "spot" || contains(["delete", "deallocate"], lower(v.eviction_policy))
+    ])
+    error_message = "When priority is 'Spot', eviction_policy must be either 'Delete' or 'Deallocate' (case-insensitive)."
+  }
+
+  validation {
+    condition = alltrue([
+      for k, v in var.node_pools : v.spot_max_price >= -1
+    ])
+    error_message = "Each node pool's spot_max_price must be greater than or equal to -1."
+  }
 }
 
 variable "network_profile" {