id of instance templates now relies on the unique id of the resource

.changelog/7358.txt

@@ -0,0 +1,3 @@
+```release-note:enhancement
+compute: added output-only attribute `self_link_unique` id for `google_compute_instance_template` to point to the unique id of the resource (instead of its name). It is recommended to use `self_link_unique` for references over `self_link` and `id` for `google_compute_instance_template`
+```

google/data_source_google_compute_instance_template.go

@@ -17,16 +17,22 @@ func DataSourceGoogleComputeInstanceTemplate() *schema.Resource {
 		Type:     schema.TypeString,
 		Optional: true,
 	}
+	dsSchema["self_link_unique"] = &schema.Schema{
+		Type:     schema.TypeString,
+		Optional: true,
+	}
 	dsSchema["most_recent"] = &schema.Schema{
 		Type:     schema.TypeBool,
 		Optional: true,
 	}
 
 	// Set 'Optional' schema elements
-	addOptionalFieldsToSchema(dsSchema, "name", "filter", "most_recent", "project")
+	addOptionalFieldsToSchema(dsSchema, "name", "filter", "most_recent", "project", "self_link_unique")
 
-	dsSchema["name"].ExactlyOneOf = []string{"name", "filter"}
-	dsSchema["filter"].ExactlyOneOf = []string{"name", "filter"}
+	mutuallyExclusive := []string{"name", "filter", "self_link_unique"}
+	for _, n := range mutuallyExclusive {
+		dsSchema[n].ExactlyOneOf = mutuallyExclusive
+	}
 
 	return &schema.Resource{
 		Read:   datasourceComputeInstanceTemplateRead,
@@ -68,8 +74,11 @@ func datasourceComputeInstanceTemplateRead(d *schema.ResourceData, meta interfac
 
 		return fmt.Errorf("your filter has returned %d instance template(s). Please refine your filter or set most_recent to return exactly one instance template", len(templates.Items))
 	}
+	if v, ok := d.GetOk("self_link_unique"); ok {
+		return retrieveInstanceFromUniqueId(d, meta, project, v.(string))
+	}
 
-	return fmt.Errorf("one of name or filters must be set")
+	return fmt.Errorf("one of name, filters or self_link_unique must be set")
 }
 
 func retrieveInstance(d *schema.ResourceData, meta interface{}, project, name string) error {
@@ -78,6 +87,14 @@ func retrieveInstance(d *schema.ResourceData, meta interface{}, project, name st
 	return resourceComputeInstanceTemplateRead(d, meta)
 }
 
+func retrieveInstanceFromUniqueId(d *schema.ResourceData, meta interface{}, project, self_link_unique string) error {
+	normalId, _ := parseUniqueId(self_link_unique)
+	d.SetId(normalId)
+	d.Set("self_link_unique", self_link_unique)
+
+	return resourceComputeInstanceTemplateRead(d, meta)
+}
+
 // ByCreationTimestamp implements sort.Interface for []*InstanceTemplate based on
 // the CreationTimestamp field.
 type ByCreationTimestamp []*compute.InstanceTemplate

google/data_source_google_compute_instance_template_test.go

@@ -69,6 +69,31 @@ func TestAccInstanceTemplateDatasource_filter_mostRecent(t *testing.T) {
 	})
 }
 
+func TestAccInstanceTemplateDatasource_self_link_unique(t *testing.T) {
+	t.Parallel()
+
+	VcrTest(t, resource.TestCase{
+		PreCheck:  func() { testAccPreCheck(t) },
+		Providers: TestAccProviders,
+		Steps: []resource.TestStep{
+			{
+				Config: testAccInstanceTemplate_self_link_unique(GetTestProjectFromEnv(), RandString(t, 10)),
+				Check: resource.ComposeTestCheckFunc(
+					checkDataSourceStateMatchesResourceStateWithIgnores(
+						"data.google_compute_instance_template.default",
+						"google_compute_instance_template.default",
+						// we don't compare the id here as we start this test from a self_link_unique url
+						// and the resource's ID will have the standard format project/projectname/global/instanceTemplates/tf-test-template-random
+						map[string]struct{}{
+							"id": {},
+						},
+					),
+				),
+			},
+		},
+	})
+}
+
 func testAccInstanceTemplate_name(project, suffix string) string {
 	return Nprintf(`
 resource "google_compute_instance_template" "default" {
@@ -238,3 +263,31 @@ data "google_compute_instance_template" "default" {
 }
 `, map[string]interface{}{"project": project, "suffix": suffix})
 }
+
+func testAccInstanceTemplate_self_link_unique(project, suffix string) string {
+	return Nprintf(`
+resource "google_compute_instance_template" "default" {
+  name        = "tf-test-template-%{suffix}"
+  description = "Example template."
+
+  machine_type = "e2-small"
+
+  tags = ["foo", "bar"]
+
+  disk {
+    source_image = "cos-cloud/cos-stable"
+    auto_delete  = true
+    boot         = true
+  }
+
+  network_interface {
+    network = "default"
+  }
+}
+
+data "google_compute_instance_template" "default" {
+  project = "%{project}"
+  self_link_unique = google_compute_instance_template.default.self_link_unique
+}
+`, map[string]interface{}{"project": project, "suffix": suffix})
+}

google/resource_compute_instance_from_template.go

@@ -118,8 +118,7 @@ func resourceComputeInstanceFromTemplateCreate(d *schema.ResourceData, meta inte
 		return err
 	}
 
-	sourceInstanceTemplate := d.Get("source_instance_template").(string)
-
+	sourceInstanceTemplate := ConvertToUniqueIdWhenPresent(d.Get("source_instance_template").(string))
 	tpl, err := ParseInstanceTemplateFieldValue(sourceInstanceTemplate, d, config)
 	if err != nil {
 		return err

google/resource_compute_instance_from_template_test.go

@@ -39,6 +39,34 @@ func TestAccComputeInstanceFromTemplate_basic(t *testing.T) {
 	})
 }
 
+func TestAccComputeInstanceFromTemplate_self_link_unique(t *testing.T) {
+	t.Parallel()
+
+	var instance compute.Instance
+	instanceName := fmt.Sprintf("tf-test-%s", RandString(t, 10))
+	templateName := fmt.Sprintf("tf-test-%s", RandString(t, 10))
+	resourceName := "google_compute_instance_from_template.foobar"
+
+	VcrTest(t, resource.TestCase{
+		PreCheck:     func() { testAccPreCheck(t) },
+		Providers:    TestAccProviders,
+		CheckDestroy: testAccCheckComputeInstanceFromTemplateDestroyProducer(t),
+		Steps: []resource.TestStep{
+			{
+				Config: testAccComputeInstanceFromTemplate_self_link_unique(instanceName, templateName),
+				Check: resource.ComposeTestCheckFunc(
+					testAccCheckComputeInstanceExists(t, resourceName, &instance),
+
+					// Check that fields were set based on the template
+					resource.TestCheckResourceAttr(resourceName, "machine_type", "n1-standard-1"),
+					resource.TestCheckResourceAttr(resourceName, "attached_disk.#", "1"),
+					resource.TestCheckResourceAttr(resourceName, "scheduling.0.automatic_restart", "false"),
+				),
+			},
+		},
+	})
+}
+
 func TestAccComputeInstanceFromRegionTemplate_basic(t *testing.T) {
 	t.Parallel()
 
@@ -413,6 +441,80 @@ resource "google_compute_instance_from_template" "foobar" {
 `, template, template, instance)
 }
 
+func testAccComputeInstanceFromTemplate_self_link_unique(instance, template string) string {
+	return fmt.Sprintf(`
+data "google_compute_image" "my_image" {
+  family  = "debian-11"
+  project = "debian-cloud"
+}
+
+resource "google_compute_disk" "foobar" {
+  name  = "%s"
+  image = data.google_compute_image.my_image.self_link
+  size  = 10
+  type  = "pd-ssd"
+  zone  = "us-central1-a"
+}
+
+resource "google_compute_instance_template" "foobar" {
+  name         = "%s"
+  machine_type = "n1-standard-1"  // can't be e2 because of local-ssd
+
+  disk {
+    source      = google_compute_disk.foobar.name
+    auto_delete = false
+    boot        = true
+  }
+
+  disk {
+    disk_type    = "local-ssd"
+    type         = "SCRATCH"
+    interface    = "NVME"
+    disk_size_gb = 375
+  }
+
+  disk {
+    source_image = data.google_compute_image.my_image.self_link
+    auto_delete  = true
+    disk_size_gb = 100
+    boot         = false
+    disk_type    = "pd-ssd"
+    type         = "PERSISTENT"
+  }
+
+  network_interface {
+    network = "default"
+  }
+
+  metadata = {
+    foo = "bar"
+  }
+
+  scheduling {
+    automatic_restart = true
+  }
+
+  can_ip_forward = true
+}
+
+resource "google_compute_instance_from_template" "foobar" {
+  name = "%s"
+  zone = "us-central1-a"
+
+  source_instance_template = google_compute_instance_template.foobar.self_link_unique
+
+  // Overrides
+  can_ip_forward = false
+  labels = {
+    my_key = "my_value"
+  }
+  scheduling {
+    automatic_restart = false
+  }
+}
+`, template, template, instance)
+}
+
 func testAccComputeInstanceFromTemplate_overrideBootDisk(templateDisk, overrideDisk, template, instance string) string {
 	return fmt.Sprintf(`
 data "google_compute_image" "my_image" {

google/resource_compute_instance_group_manager.go

@@ -50,7 +50,7 @@ func ResourceComputeInstanceGroupManager() *schema.Resource {
 						"instance_template": {
 							Type:             schema.TypeString,
 							Required:         true,
-							DiffSuppressFunc: compareSelfLinkRelativePaths,
+							DiffSuppressFunc: compareSelfLinkRelativePathsIgnoreParams,
 							Description:      `The full URL to an instance template from which all new instances of this version will be created.`,
 						},
 
@@ -371,6 +371,33 @@ func ResourceComputeInstanceGroupManager() *schema.Resource {
 	}
 }
 
+func parseUniqueId(s string) (string, string) {
+	splits := strings.SplitN(s, "?uniqueId=", 2)
+	if len(splits) == 2 {
+		return splits[0], splits[1]
+	}
+	return s, ""
+}
+
+func compareSelfLinkRelativePathsIgnoreParams(_unused1, old, new string, _unused2 *schema.ResourceData) bool {
+	oldName, oldUniqueId := parseUniqueId(old)
+	newName, newUniqueId := parseUniqueId(new)
+	if oldUniqueId != "" && newUniqueId != "" && oldUniqueId != newUniqueId {
+		return false
+	}
+	return compareSelfLinkRelativePaths(_unused1, oldName, newName, _unused2)
+}
+
+func ConvertToUniqueIdWhenPresent(s string) string {
+	original, uniqueId := parseUniqueId(s)
+	if uniqueId != "" {
+		splits := strings.Split(original, "/")
+		splits[len(splits)-1] = uniqueId
+		return strings.Join(splits, "/")
+	}
+	return s
+}
+
 func getNamedPorts(nps []interface{}) []*compute.NamedPort {
 	namedPorts := make([]*compute.NamedPort, 0, len(nps))
 	for _, v := range nps {
@@ -935,7 +962,7 @@ func expandVersions(configured []interface{}) []*compute.InstanceGroupManagerVer
 
 		version := compute.InstanceGroupManagerVersion{
 			Name:             data["name"].(string),
-			InstanceTemplate: data["instance_template"].(string),
+			InstanceTemplate: ConvertToUniqueIdWhenPresent(data["instance_template"].(string)),
 			TargetSize:       expandFixedOrPercent(data["target_size"].([]interface{})),
 		}