[#11206] Add redundant_interface argument to cloud router interface

.changelog/6740.txt

@@ -0,0 +1,3 @@
+```release-note:enhancement
+compute: Added optional `redundant_interface` argument to `google_compute_router_interface` resource
+```

google/resource_compute_router_interface.go

@@ -80,6 +80,13 @@ func resourceComputeRouterInterface() *schema.Resource {
 				ForceNew:    true,
 				Description: `The region this interface's router sits in. If not specified, the project region will be used. Changing this forces a new interface to be created.`,
 			},
+
+			"redundant_interface": {
+				Type:        schema.TypeString,
+				Optional:    true,
+				ForceNew:    true,
+				Description: `The name of the interface that is redundant to this interface.`,
+			},
 		},
 		UseJSONNumber: true,
 	}
@@ -123,6 +130,7 @@ func resourceComputeRouterInterfaceCreate(d *schema.ResourceData, meta interface
 	}
 
 	ifaces := router.Interfaces
+
 	for _, iface := range ifaces {
 		if iface.Name == ifaceName {
 			d.SetId("")
@@ -132,6 +140,10 @@ func resourceComputeRouterInterfaceCreate(d *schema.ResourceData, meta interface
 
 	iface := &compute.RouterInterface{Name: ifaceName}
 
+	if riVal, ok := d.GetOk("redundant_interface"); ok {
+		iface.RedundantInterface = riVal.(string)
+	}
+
 	if ipVal, ok := d.GetOk("ip_range"); ok {
 		iface.IpRange = ipVal.(string)
 	}
@@ -225,6 +237,9 @@ func resourceComputeRouterInterfaceRead(d *schema.ResourceData, meta interface{}
 			if err := d.Set("project", project); err != nil {
 				return fmt.Errorf("Error setting project: %s", err)
 			}
+			if err := d.Set("redundant_interface", iface.RedundantInterface); err != nil {
+				return fmt.Errorf("Error setting redundant interface: %s", err)
+			}
 			return nil
 		}
 	}

google/resource_compute_router_interface_test.go

@@ -36,6 +36,29 @@ func TestAccComputeRouterInterface_basic(t *testing.T) {
 	})
 }
 
+func TestAccComputeRouterInterface_redundant(t *testing.T) {
+	t.Parallel()
+
+	routerName := fmt.Sprintf("tf-test-router-%s", randString(t, 10))
+	vcrTest(t, resource.TestCase{
+		PreCheck:     func() { testAccPreCheck(t) },
+		Providers:    testAccProviders,
+		CheckDestroy: testAccCheckComputeRouterInterfaceDestroyProducer(t),
+		Steps: []resource.TestStep{
+			{
+				Config: testAccComputeRouterInterfaceRedundant(routerName),
+				Check: testAccCheckComputeRouterInterfaceExists(
+					t, "google_compute_router_interface.foobar_int2"),
+			},
+			{
+				ResourceName:      "google_compute_router_interface.foobar_int2",
+				ImportState:       true,
+				ImportStateVerify: true,
+			},
+		},
+	})
+}
+
 func TestAccComputeRouterInterface_withTunnel(t *testing.T) {
 	t.Parallel()
 
@@ -249,6 +272,45 @@ resource "google_compute_router_interface" "foobar" {
 `, routerName, routerName, routerName, routerName, routerName, routerName, routerName, routerName, routerName)
 }
 
+func testAccComputeRouterInterfaceRedundant(routerName string) string {
+	return fmt.Sprintf(`
+resource "google_compute_network" "foobar" {
+  name = "%s-net"
+}
+
+resource "google_compute_subnetwork" "foobar" {
+  name          = "%s-subnet"
+  network       = google_compute_network.foobar.self_link
+  ip_cidr_range = "10.0.0.0/16"
+  region        = "us-central1"
+}
+
+resource "google_compute_router" "foobar" {
+  name    = "%s"
+  region  = google_compute_subnetwork.foobar.region
+  network = google_compute_network.foobar.self_link
+  bgp {
+    asn = 64514
+  }
+}
+
+resource "google_compute_router_interface" "foobar_int1" {
+  name     = "%s-int1"
+  router   = google_compute_router.foobar.name
+  region   = google_compute_router.foobar.region
+  ip_range = "169.254.3.1/30"
+}
+
+resource "google_compute_router_interface" "foobar_int2" {
+  name                = "%s-int2"
+  router              = google_compute_router.foobar.name
+  region              = google_compute_router.foobar.region
+  ip_range            = "169.254.4.1/30"
+  redundant_interface = google_compute_router_interface.foobar_int1.name
+}
+`, routerName, routerName, routerName, routerName, routerName)
+}
+
 func testAccComputeRouterInterfaceKeepRouter(routerName string) string {
 	return fmt.Sprintf(`
 resource "google_compute_network" "foobar" {

website/docs/r/compute_router_interface.html.markdown

@@ -52,6 +52,10 @@ or both.
   be created. Only one of `vpn_tunnel` and `interconnect_attachment` can be
   specified.
 
+* `redundant_interface` - (Optional) The name of the interface that is redundant to
+  this interface. Changing this forces a new interface to
+  be created.
+
 * `project` - (Optional) The ID of the project in which this interface's router belongs. If it
     is not provided, the provider project is used. Changing this forces a new interface to be created.