012 instance from template (#3434)

Signed-off-by: Modular Magician <magic-modules@google.com>

go.sum

@@ -121,6 +121,7 @@ github.com/google/go-querystring v1.0.0 h1:Xkwi/a1rcvNg1PPYe5vI8GbeBY/jrVuDX5ASu
 github.com/google/go-querystring v1.0.0/go.mod h1:odCYkC5MyYFN7vkCjXpyrEuKhc/BUO6wN/zVPAxq5ck=
 github.com/google/martian v2.1.0+incompatible/go.mod h1:9I4somxYTbIHy5NJKHRl3wXiIaQGbYVAs8BPL6v8lEs=
 github.com/google/pprof v0.0.0-20181206194817-3ea8567a2e57/go.mod h1:zfwlbNMJ+OItoe0UupaVj+oy1omPYYDuagoSzA8v9mc=
+github.com/googleapis/gax-go v2.0.0+incompatible h1:j0GKcs05QVmm7yesiZq2+9cxHkNK9YM6zKx4D2qucQU=
 github.com/googleapis/gax-go v2.0.0+incompatible/go.mod h1:SFVmujtThgffbyetf+mdk2eWhX2bMyUtNHzFKcPA9HY=
 github.com/googleapis/gax-go/v2 v2.0.3 h1:siORttZ36U2R/WjiJuDz8znElWBiAlO9rVt+mqJt0Cc=
 github.com/googleapis/gax-go/v2 v2.0.3/go.mod h1:LLvjysVCY1JZeum8Z6l8qUty8fiNwE08qbEPm1M08qg=

google/resource_compute_instance.go

@@ -370,10 +370,11 @@ func resourceComputeInstance() *schema.Resource {
 			},
 
 			"guest_accelerator": {
-				Type:     schema.TypeList,
-				Optional: true,
-				Computed: true,
-				ForceNew: true,
+				Type:       schema.TypeList,
+				Optional:   true,
+				Computed:   true,
+				ForceNew:   true,
+				ConfigMode: schema.SchemaConfigModeAttr,
 				Elem: &schema.Resource{
 					Schema: map[string]*schema.Schema{
 						"count": {

google/resource_compute_instance_from_template.go

@@ -37,6 +37,17 @@ func computeInstanceFromTemplateSchema() map[string]*schema.Schema {
 		s[field].Optional = true
 	}
 
+	// schema.SchemaConfigModeAttr allows these fields to be removed in Terraform 0.12.
+	// Passing field_name = [] in this mode differentiates between an intentionally empty
+	// block vs an ignored computed block.
+	nic := s["network_interface"].Elem.(*schema.Resource)
+	nic.Schema["alias_ip_range"].ConfigMode = schema.SchemaConfigModeAttr
+	nic.Schema["access_config"].ConfigMode = schema.SchemaConfigModeAttr
+
+	for _, field := range []string{"attached_disk", "guest_accelerator", "service_account", "scratch_disk"} {
+		s[field].ConfigMode = schema.SchemaConfigModeAttr
+	}
+
 	// Remove deprecated/removed fields that are never d.Set. We can't
 	// programatically remove all of them, because some of them still have d.Set
 	// calls.

google/resource_compute_instance_from_template_test.go

@@ -125,6 +125,50 @@ func TestAccComputeInstanceFromTemplate_overrideScratchDisk(t *testing.T) {
 	})
 }
 
+func TestAccComputeInstanceFromTemplate_012_removableFields(t *testing.T) {
+	t.Parallel()
+
+	var instance compute.Instance
+	instanceName := fmt.Sprintf("terraform-test-%s", acctest.RandString(10))
+	templateName := fmt.Sprintf("terraform-test-%s", acctest.RandString(10))
+	resourceName := "google_compute_instance_from_template.inst"
+
+	// First config is a basic instance from template, second tests the empty list syntax
+	config1 := testAccComputeInstanceFromTemplate_012_removableFieldsTpl(templateName) +
+		testAccComputeInstanceFromTemplate_012_removableFields1(instanceName)
+	config2 := testAccComputeInstanceFromTemplate_012_removableFieldsTpl(templateName) +
+		testAccComputeInstanceFromTemplate_012_removableFields2(instanceName)
+
+	resource.Test(t, resource.TestCase{
+		PreCheck:     func() { testAccPreCheck(t) },
+		Providers:    testAccProviders,
+		CheckDestroy: testAccCheckComputeInstanceFromTemplateDestroy,
+		Steps: []resource.TestStep{
+			{
+				Config: config1,
+				Check: resource.ComposeTestCheckFunc(
+					testAccCheckComputeInstanceExists(resourceName, &instance),
+
+					resource.TestCheckResourceAttr(resourceName, "service_account.#", "1"),
+					resource.TestCheckResourceAttr(resourceName, "service_account.0.scopes.#", "3"),
+				),
+			},
+			{
+				Config: config2,
+				Check: resource.ComposeTestCheckFunc(
+					testAccCheckComputeInstanceExists(resourceName, &instance),
+
+					// Check that fields were able to be removed
+					resource.TestCheckResourceAttr(resourceName, "service_account.#", "0"),
+					resource.TestCheckResourceAttr(resourceName, "scratch_disk.#", "0"),
+					resource.TestCheckResourceAttr(resourceName, "attached_disk.#", "0"),
+					resource.TestCheckResourceAttr(resourceName, "network_interface.0.alias_ip_range.#", "0"),
+				),
+			},
+		},
+	})
+}
+
 func testAccCheckComputeInstanceFromTemplateDestroy(s *terraform.State) error {
 	config := testAccProvider.Meta().(*Config)
 
@@ -390,3 +434,81 @@ resource "google_compute_instance_from_template" "inst" {
 }
 `, templateDisk, overrideDisk, template, instance)
 }
+
+func testAccComputeInstanceFromTemplate_012_removableFieldsTpl(template string) string {
+
+	return fmt.Sprintf(`
+data "google_compute_image" "my_image" {
+	family  = "debian-9"
+	project = "debian-cloud"
+}
+
+resource "google_compute_instance_template" "foobar" {
+	name = "%s"
+	machine_type = "n1-standard-1"
+
+	disk {
+		source_image = "${data.google_compute_image.my_image.self_link}"
+		auto_delete = true
+		disk_size_gb = 20
+		boot = true
+	}
+
+	network_interface {
+		network = "default"
+	}
+
+	metadata = {
+		foo = "bar"
+	}
+
+	service_account {
+		scopes = ["userinfo-email", "compute-ro", "storage-ro"]
+	}
+
+	can_ip_forward = true
+}
+`, template)
+}
+
+func testAccComputeInstanceFromTemplate_012_removableFields1(instance string) string {
+	return fmt.Sprintf(`
+resource "google_compute_instance_from_template" "inst" {
+	name           = "%s"
+	zone           = "us-central1-a"
+
+	allow_stopping_for_update = true
+
+	source_instance_template = "${google_compute_instance_template.foobar.self_link}"
+}
+`, instance)
+}
+
+func testAccComputeInstanceFromTemplate_012_removableFields2(instance string) string {
+	return fmt.Sprintf(`
+resource "google_compute_instance_from_template" "inst" {
+	name           = "%s"
+	zone           = "us-central1-a"
+
+	allow_stopping_for_update = true
+
+	source_instance_template = "${google_compute_instance_template.foobar.self_link}"
+
+	// Overrides
+	network_interface {
+		alias_ip_range = []
+	}
+
+	service_account = []
+
+	scratch_disk = []
+
+	attached_disk = []
+
+	timeouts {
+		create = "10m"
+		update = "10m"
+	}
+}
+`, instance)
+}

google/resource_compute_subnetwork.go

@@ -117,6 +117,7 @@ func resourceComputeSubnetwork() *schema.Resource {
 			},
 			"secondary_ip_range": {
 				Type:     schema.TypeList,
+				Computed: true,
 				Optional: true,
 				Elem: &schema.Resource{
 					Schema: map[string]*schema.Schema{

website/docs/r/compute_instance_from_template.html.markdown

@@ -76,6 +76,14 @@ In addition to these, all arguments from `google_compute_instance` are supported
 as a way to override the properties in the template. All exported attributes
 from `google_compute_instance` are likewise exported here.
 
+To support removal of Optional/Computed fields in Terraform 0.12 the following fields
+are marked [Attributes as Blocks](/docs/configuration/attr-as-blocks.html):
+* `attached_disk`
+* `guest_accelerator`
+* `service_account`
+* `scratch_disk`
+* `network_interface.alias_ip_range`
+* `network_interface.access_config`
 
 ## Timeouts