Support for GKE dual-stack clusters

.changelog/7459.txt

@@ -0,0 +1,3 @@
+```release-note:enhancement
+container: added `stack_type` field to `google_container_cluster` resource
+```

google/resource_container_cluster.go

@@ -1245,6 +1245,15 @@ func ResourceContainerCluster() *schema.Resource {
 							ConflictsWith: ipAllocationCidrBlockFields,
 							Description:   `The name of the existing secondary range in the cluster's subnetwork to use for service ClusterIPs. Alternatively, services_ipv4_cidr_block can be used to automatically create a GKE-managed one.`,
 						},
+
+						"stack_type": {
+							Type:         schema.TypeString,
+							Optional:     true,
+							ForceNew:     true,
+							Default:      "IPV4",
+							ValidateFunc: validation.StringInSlice([]string{"IPV4", "IPV4_IPV6"}, false),
+							Description:  `The IP Stack type of the cluster. Choose between IPV4 and IPV4_IPV6. Default type is IPV4 Only if not set`,
+						},
 					},
 				},
 			},
@@ -3489,6 +3498,7 @@ func expandClusterAddonsConfig(configured interface{}) *container.AddonsConfig {
 }
 
 func expandIPAllocationPolicy(configured interface{}, networkingMode string) (*container.IPAllocationPolicy, error) {
+
 	l := configured.([]interface{})
 	if len(l) == 0 || l[0] == nil {
 		if networkingMode == "VPC_NATIVE" {
@@ -3497,20 +3507,23 @@ func expandIPAllocationPolicy(configured interface{}, networkingMode string) (*c
 		return &container.IPAllocationPolicy{
 			UseIpAliases:    false,
 			UseRoutes:       true,
+			StackType:       "IPV4",
 			ForceSendFields: []string{"UseIpAliases"},
 		}, nil
 	}
 
 	config := l[0].(map[string]interface{})
-	return &container.IPAllocationPolicy{
-		UseIpAliases:          networkingMode == "VPC_NATIVE" || networkingMode == "",
-		ClusterIpv4CidrBlock:  config["cluster_ipv4_cidr_block"].(string),
-		ServicesIpv4CidrBlock: config["services_ipv4_cidr_block"].(string),
+	stackType := config["stack_type"].(string)
 
+	return &container.IPAllocationPolicy{
+		UseIpAliases:               networkingMode == "VPC_NATIVE" || networkingMode == "",
+		ClusterIpv4CidrBlock:       config["cluster_ipv4_cidr_block"].(string),
+		ServicesIpv4CidrBlock:      config["services_ipv4_cidr_block"].(string),
 		ClusterSecondaryRangeName:  config["cluster_secondary_range_name"].(string),
 		ServicesSecondaryRangeName: config["services_secondary_range_name"].(string),
 		ForceSendFields:            []string{"UseIpAliases"},
 		UseRoutes:                  networkingMode == "ROUTES",
+		StackType:                  stackType,
 	}, nil
 }
 
@@ -4477,12 +4490,14 @@ func flattenIPAllocationPolicy(c *container.Cluster, d *schema.ResourceData, con
 	}
 
 	p := c.IpAllocationPolicy
+
 	return []map[string]interface{}{
 		{
 			"cluster_ipv4_cidr_block":       p.ClusterIpv4CidrBlock,
 			"services_ipv4_cidr_block":      p.ServicesIpv4CidrBlock,
 			"cluster_secondary_range_name":  p.ClusterSecondaryRangeName,
 			"services_secondary_range_name": p.ServicesSecondaryRangeName,
+			"stack_type":                    p.StackType,
 		},
 	}, nil
 }

google/resource_container_cluster_test.go

@@ -1958,6 +1958,62 @@ func TestAccContainerCluster_withIPAllocationPolicy_specificSizes(t *testing.T)
 	})
 }
 
+func TestAccContainerCluster_stackType_withDualStack(t *testing.T) {
+	t.Parallel()
+
+	clusterName := fmt.Sprintf("tf-test-cluster-%s", RandString(t, 10))
+	containerNetName := fmt.Sprintf("tf-test-cluster-%s", RandString(t, 10))
+	resourceName := "google_container_cluster.with_stack_type"
+
+	VcrTest(t, resource.TestCase{
+		PreCheck:                 func() { testAccPreCheck(t) },
+		ProtoV5ProviderFactories: ProtoV5ProviderFactories(t),
+		CheckDestroy:             testAccCheckContainerClusterDestroyProducer(t),
+		Steps: []resource.TestStep{
+			{
+				Config: testAccContainerCluster_stackType_withDualStack(containerNetName, clusterName),
+				Check: resource.ComposeTestCheckFunc(
+					resource.TestCheckResourceAttr(resourceName, "ip_allocation_policy.0.stack_type", "IPV4_IPV6"),
+				),
+			},
+			{
+				ResourceName:            resourceName,
+				ImportState:             true,
+				ImportStateVerify:       true,
+				ImportStateVerifyIgnore: []string{"min_master_version"},
+			},
+		},
+	})
+}
+
+func TestAccContainerCluster_stackType_withSingleStack(t *testing.T) {
+	t.Parallel()
+
+	clusterName := fmt.Sprintf("tf-test-cluster-%s", RandString(t, 10))
+	containerNetName := fmt.Sprintf("tf-test-cluster-%s", RandString(t, 10))
+	resourceName := "google_container_cluster.with_stack_type"
+
+	VcrTest(t, resource.TestCase{
+		PreCheck:                 func() { testAccPreCheck(t) },
+		ProtoV5ProviderFactories: ProtoV5ProviderFactories(t),
+		CheckDestroy:             testAccCheckContainerClusterDestroyProducer(t),
+		Steps: []resource.TestStep{
+			{
+				Config: testAccContainerCluster_stackType_withSingleStack(containerNetName, clusterName),
+				Check: resource.ComposeTestCheckFunc(
+					resource.TestCheckResourceAttr(resourceName, "ip_allocation_policy.0.stack_type", "IPV4"),
+				),
+			},
+			{
+				ResourceName:            resourceName,
+				ImportState:             true,
+				ImportStateVerify:       true,
+				ImportStateVerifyIgnore: []string{"min_master_version"},
+			},
+		},
+	})
+}
+
 func TestAccContainerCluster_nodeAutoprovisioning(t *testing.T) {
 	t.Parallel()
 
@@ -5444,6 +5500,77 @@ resource "google_container_cluster" "with_ip_allocation_policy" {
 `, containerNetName, clusterName)
 }
 
+func testAccContainerCluster_stackType_withDualStack(containerNetName string, clusterName string) string {
+	return fmt.Sprintf(`
+resource "google_compute_network" "container_network" {
+    name                    = "%s"
+    auto_create_subnetworks = false
+}
+
+    resource "google_compute_subnetwork" "container_subnetwork" {
+    name    = google_compute_network.container_network.name
+    network = google_compute_network.container_network.name
+    region  = "us-central1"
+
+    ip_cidr_range = "10.2.0.0/16"
+    stack_type = "IPV4_IPV6"
+    ipv6_access_type = "EXTERNAL"
+}
+
+resource "google_container_cluster" "with_stack_type" {
+    name       = "%s"
+    location   = "us-central1-a"
+    network    = google_compute_network.container_network.name
+    subnetwork = google_compute_subnetwork.container_subnetwork.name
+
+    min_master_version = "1.25"
+    initial_node_count = 1
+    datapath_provider = "ADVANCED_DATAPATH"
+    enable_l4_ilb_subsetting = true
+
+    ip_allocation_policy {
+        cluster_ipv4_cidr_block  = "10.0.0.0/16"
+        services_ipv4_cidr_block = "10.1.0.0/16"
+        stack_type = "IPV4_IPV6"
+    }
+}
+`, containerNetName, clusterName)
+}
+
+func testAccContainerCluster_stackType_withSingleStack(containerNetName string, clusterName string) string {
+	return fmt.Sprintf(`
+resource "google_compute_network" "container_network" {
+    name                    = "%s"
+    auto_create_subnetworks = false
+}
+
+    resource "google_compute_subnetwork" "container_subnetwork" {
+    name    = google_compute_network.container_network.name
+    network = google_compute_network.container_network.name
+    region  = "us-central1"
+
+    ip_cidr_range = "10.2.0.0/16"
+}
+
+resource "google_container_cluster" "with_stack_type" {
+    name       = "%s"
+    location   = "us-central1-a"
+    network    = google_compute_network.container_network.name
+    subnetwork = google_compute_subnetwork.container_subnetwork.name
+
+    min_master_version = "1.25"
+    initial_node_count = 1
+    enable_l4_ilb_subsetting = true
+
+    ip_allocation_policy {
+        cluster_ipv4_cidr_block  = "10.0.0.0/16"
+        services_ipv4_cidr_block = "10.1.0.0/16"
+        stack_type = "IPV4"
+    }
+}
+`, containerNetName, clusterName)
+}
+
 func testAccContainerCluster_withResourceUsageExportConfig(clusterName, datasetId, enableMetering string) string {
 	return fmt.Sprintf(`
 provider "google" {

website/docs/r/container_cluster.html.markdown

@@ -691,6 +691,10 @@ to have a range chosen with a specific netmask. Set to a CIDR notation (e.g. 10.
 from the RFC-1918 private networks (e.g. 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16) to
 pick a specific range to use.
 
+* `stack_type` - (Optional) The IP Stack Type of the cluster. 
+Default value is `IPV4`.
+Possible values are `IPV4` and `PV4_IPV6`.
+
 <a name="nested_master_auth"></a>The `master_auth` block supports:
 
 * `client_certificate_config` - (Required) Whether client certificate authorization is enabled for this cluster.  For example: