azurerm_postgresql_server - force new if sku_name changes tier (h…

…ashicorp#7456)

Fix :hashicorp#7131

=== RUN TestAccAzureRMPostgreSQLServer_updateSKU
=== PAUSE TestAccAzureRMPostgreSQLServer_updateSKU
=== CONT TestAccAzureRMPostgreSQLServer_updateSKU
--- PASS: TestAccAzureRMPostgreSQLServer_updateSKU (632.60s)
PASS

azurerm/internal/services/postgres/postgresql_server_resource.go

@@ -10,6 +10,7 @@ import (
 	"github.com/Azure/azure-sdk-for-go/services/postgresql/mgmt/2017-12-01/postgresql"
 	"github.com/Azure/go-autorest/autorest/date"
 	"github.com/hashicorp/go-azure-helpers/response"
+	"github.com/hashicorp/terraform-plugin-sdk/helper/customdiff"
 	"github.com/hashicorp/terraform-plugin-sdk/helper/schema"
 	"github.com/hashicorp/terraform-plugin-sdk/helper/validation"
 	"github.com/terraform-providers/terraform-provider-azurerm/azurerm/helpers/azure"
@@ -348,6 +349,22 @@ func resourceArmPostgreSQLServer() *schema.Resource {
 
 			"tags": tags.Schema(),
 		},
+
+		CustomizeDiff: customdiff.All(
+			customdiff.ForceNewIfChange("sku_name", func(old, new, meta interface{}) bool {
+				oldTier := strings.Split(old.(string), "_")
+				newTier := strings.Split(new.(string), "_")
+				// If the sku tier was not changed, we don't need fornew
+				if oldTier[0] == newTier[0] {
+					return false
+				}
+				// Basic tier could not be changed to other tiers
+				if oldTier[0] == "B" || newTier[0] == "B" {
+					return true
+				}
+				return false
+			}),
+		),
 	}
 }
 

azurerm/internal/services/postgres/tests/postgresql_server_resource_test.go

@@ -311,6 +311,13 @@ func TestAccAzureRMPostgreSQLServer_updateSKU(t *testing.T) {
 		Providers:    acceptance.SupportedProviders,
 		CheckDestroy: testCheckAzureRMPostgreSQLServerDestroy,
 		Steps: []resource.TestStep{
+			{
+				Config: testAccAzureRMPostgreSQLServer_sku(data, "10.0", "B_Gen5_2"),
+				Check: resource.ComposeTestCheckFunc(
+					testCheckAzureRMPostgreSQLServerExists(data.ResourceName),
+				),
+			},
+			data.ImportStep("administrator_login_password"),
 			{
 				Config: testAccAzureRMPostgreSQLServer_sku(data, "10.0", "GP_Gen5_2"),
 				Check: resource.ComposeTestCheckFunc(