refact: move check to CustomizeDiff to run during plan

Author: Kiliandeca

internal/services/containers/kubernetes_cluster_node_pool_resource.go

@@ -88,6 +88,34 @@ func resourceKubernetesClusterNodePool() *pluginsdk.Resource {
 			pluginsdk.ForceNewIfChange("upgrade_settings.0.undrainable_node_behavior", func(ctx context.Context, old, new, meta interface{}) bool {
 				return old != "" && new == ""
 			}),
+			func(ctx context.Context, d *pluginsdk.ResourceDiff, meta interface{}) error {
+				priority := d.Get("priority").(string)
+				isSpot := priority == string(agentpools.ScaleSetPrioritySpot)
+
+				upgradeSettingsRaw := d.Get("upgrade_settings").([]interface{})
+				if len(upgradeSettingsRaw) == 0 || upgradeSettingsRaw[0] == nil {
+					return nil
+				}
+
+				upgradeSettings := upgradeSettingsRaw[0].(map[string]interface{})
+				maxSurgeRaw := upgradeSettings["max_surge"].(string)
+				maxUnavailableRaw := upgradeSettings["max_unavailable"].(string)
+
+				if isSpot {
+					if maxSurgeRaw != "" {
+						return fmt.Errorf("`max_surge` cannot be set when `priority` is set to `Spot`. Spot pools do not support `max_surge`")
+					}
+					if maxUnavailableRaw != "" {
+						return fmt.Errorf("`max_unavailable` cannot be set when `priority` is set to `Spot`. Spot pools do not support `max_unavailable`")
+					}
+				} else {
+					if maxSurgeRaw == "" && maxUnavailableRaw == "" {
+						return fmt.Errorf("either `max_surge` or `max_unavailable` must be specified in `upgrade_settings` when `priority` is not `Spot`")
+					}
+				}
+
+				return nil
+			},
 		),
 	}
 
@@ -523,11 +551,6 @@ func resourceKubernetesClusterNodePoolCreate(d *pluginsdk.ResourceData, meta int
 	spotMaxPrice := d.Get("spot_max_price").(float64)
 	t := d.Get("tags").(map[string]interface{})
 
-	upgradeSettings, err := expandAgentPoolUpgradeSettings(d.Get("upgrade_settings").([]interface{}), priority)
-	if err != nil {
-		return err
-	}
-
 	profile := agentpools.ManagedClusterAgentPoolProfileProperties{
 		OsType:                 pointer.To(agentpools.OSType(osType)),
 		EnableAutoScaling:      pointer.To(enableAutoScaling),
@@ -541,7 +564,7 @@ func resourceKubernetesClusterNodePoolCreate(d *pluginsdk.ResourceData, meta int
 		Tags:                   tags.Expand(t),
 		Type:                   pointer.To(agentpools.AgentPoolTypeVirtualMachineScaleSets),
 		VMSize:                 pointer.To(d.Get("vm_size").(string)),
-		UpgradeSettings:        upgradeSettings,
+		UpgradeSettings:        expandAgentPoolUpgradeSettings(d.Get("upgrade_settings").([]interface{}), priority),
 		WindowsProfile:         expandAgentPoolWindowsProfile(d.Get("windows_profile").([]interface{})),
 
 		// this must always be sent during creation, but is optional for auto-scaled clusters during update
@@ -885,11 +908,7 @@ func resourceKubernetesClusterNodePoolUpdate(d *pluginsdk.ResourceData, meta int
 	if d.HasChange("upgrade_settings") {
 		upgradeSettingsRaw := d.Get("upgrade_settings").([]interface{})
 		priority := d.Get("priority").(string)
-		upgradeSettings, err := expandAgentPoolUpgradeSettings(upgradeSettingsRaw, priority)
-		if err != nil {
-			return err
-		}
-		props.UpgradeSettings = upgradeSettings
+		props.UpgradeSettings = expandAgentPoolUpgradeSettings(upgradeSettingsRaw, priority)
 	}
 
 	if d.HasChange("scale_down_mode") {
@@ -1279,7 +1298,6 @@ func upgradeSettingsSchemaNodePoolResource() *pluginsdk.Schema {
 					Optional:      true,
 					ValidateFunc:  validation.StringIsNotEmpty,
 					ConflictsWith: []string{"upgrade_settings.0.max_unavailable"},
-					Description:   "The maximum number of nodes that can be created during upgrade. This cannot be set when `priority` is set to `Spot`.",
 				},
 				"drain_timeout_in_minutes": {
 					Type:         pluginsdk.TypeInt,
@@ -1291,7 +1309,6 @@ func upgradeSettingsSchemaNodePoolResource() *pluginsdk.Schema {
 					Optional:      true,
 					ValidateFunc:  validation.StringIsNotEmpty,
 					ConflictsWith: []string{"upgrade_settings.0.max_surge"},
-					Description:   "The maximum number of nodes that can be unavailable during upgrade. This cannot be set when `priority` is set to `Spot`.",
 				},
 				"node_soak_duration_in_minutes": {
 					Type:         pluginsdk.TypeInt,
@@ -1380,10 +1397,10 @@ func expandAgentPoolKubeletConfig(input []interface{}) *agentpools.KubeletConfig
 	return result
 }
 
-func expandAgentPoolUpgradeSettings(input []interface{}, priority string) (*agentpools.AgentPoolUpgradeSettings, error) {
+func expandAgentPoolUpgradeSettings(input []interface{}, priority string) *agentpools.AgentPoolUpgradeSettings {
 	setting := &agentpools.AgentPoolUpgradeSettings{}
 	if len(input) == 0 || input[0] == nil {
-		return nil, nil
+		return nil
 	}
 
 	v := input[0].(map[string]interface{})
@@ -1392,20 +1409,7 @@ func expandAgentPoolUpgradeSettings(input []interface{}, priority string) (*agen
 	maxSurgeRaw := v["max_surge"].(string)
 	maxUnavailableRaw := v["max_unavailable"].(string)
 
-	if isSpot {
-		if maxSurgeRaw != "" {
-			return nil, fmt.Errorf("`max_surge` cannot be set when `priority` is set to `Spot`. Spot pools do not support `max_surge`")
-		}
-		if maxUnavailableRaw != "" {
-			return nil, fmt.Errorf("`max_unavailable` cannot be set when `priority` is set to `Spot`. Spot pools do not support `max_unavailable`")
-		}
-	}
-
 	if !isSpot {
-		if maxSurgeRaw == "" && maxUnavailableRaw == "" {
-			return nil, fmt.Errorf("either `max_surge` or `max_unavailable` must be specified in `upgrade_settings` when `priority` is not `Spot`")
-		}
-
 		if maxSurgeRaw != "" {
 			setting.MaxSurge = pointer.To(maxSurgeRaw)
 			setting.MaxUnavailable = pointer.To("0")
@@ -1425,7 +1429,7 @@ func expandAgentPoolUpgradeSettings(input []interface{}, priority string) (*agen
 	if undrainableNodeBehaviorRaw, ok := v["undrainable_node_behavior"].(string); ok && undrainableNodeBehaviorRaw != "" {
 		setting.UndrainableNodeBehavior = pointer.To(agentpools.UndrainableNodeBehavior(undrainableNodeBehaviorRaw))
 	}
-	return setting, nil
+	return setting
 }
 
 func flattenAgentPoolUpgradeSettings(input *agentpools.AgentPoolUpgradeSettings) []interface{} {