provider/google: Add support for draining_timeout_sec to compute_backend_service.

builtin/providers/google/resource_compute_backend_service.go

@@ -139,6 +139,12 @@ func resourceComputeBackendService() *schema.Resource {
 				Optional: true,
 				Computed: true,
 			},
+
+			"connection_draining_timeout_sec": &schema.Schema{
+				Type:     schema.TypeInt,
+				Optional: true,
+				Default:  0,
+			},
 		},
 	}
 }
@@ -185,6 +191,14 @@ func resourceComputeBackendServiceCreate(d *schema.ResourceData, meta interface{
 		service.EnableCDN = v.(bool)
 	}
 
+	if v, ok := d.GetOk("connection_draining_timeout_sec"); ok {
+		connectionDraining := &compute.ConnectionDraining{
+			DrainingTimeoutSec: int64(v.(int)),
+		}
+
+		service.ConnectionDraining = connectionDraining
+	}
+
 	project, err := getProject(d, config)
 	if err != nil {
 		return err
@@ -235,8 +249,9 @@ func resourceComputeBackendServiceRead(d *schema.ResourceData, meta interface{})
 	d.Set("timeout_sec", service.TimeoutSec)
 	d.Set("fingerprint", service.Fingerprint)
 	d.Set("self_link", service.SelfLink)
-
 	d.Set("backend", flattenBackends(service.Backends))
+	d.Set("connection_draining_timeout_sec", service.ConnectionDraining.DrainingTimeoutSec)
+
 	d.Set("health_checks", service.HealthChecks)
 
 	return nil
@@ -279,6 +294,14 @@ func resourceComputeBackendServiceUpdate(d *schema.ResourceData, meta interface{
 		service.TimeoutSec = int64(v.(int))
 	}
 
+	if d.HasChange("connection_draining_timeout_sec") {
+		connectionDraining := &compute.ConnectionDraining{
+			DrainingTimeoutSec: int64(d.Get("connection_draining_timeout_sec").(int)),
+		}
+
+		service.ConnectionDraining = connectionDraining
+	}
+
 	if d.HasChange("session_affinity") {
 		service.SessionAffinity = d.Get("session_affinity").(string)
 	}

builtin/providers/google/resource_compute_backend_service_test.go

@@ -114,6 +114,63 @@ func TestAccComputeBackendService_withBackendAndUpdate(t *testing.T) {
 	}
 }
 
+func TestAccComputeBackendService_withConnectionDraining(t *testing.T) {
+	serviceName := fmt.Sprintf("tf-test-%s", acctest.RandString(10))
+	checkName := fmt.Sprintf("tf-test-%s", acctest.RandString(10))
+	var svc compute.BackendService
+
+	resource.Test(t, resource.TestCase{
+		PreCheck:     func() { testAccPreCheck(t) },
+		Providers:    testAccProviders,
+		CheckDestroy: testAccCheckComputeBackendServiceDestroy,
+		Steps: []resource.TestStep{
+			resource.TestStep{
+				Config: testAccComputeBackendService_withConnectionDraining(serviceName, checkName, 10),
+				Check: resource.ComposeTestCheckFunc(
+					testAccCheckComputeBackendServiceExists(
+						"google_compute_backend_service.foobar", &svc),
+				),
+			},
+		},
+	})
+
+	if svc.ConnectionDraining.DrainingTimeoutSec != 10 {
+		t.Errorf("Expected ConnectionDraining.DrainingTimeoutSec == 10, got %d", svc.ConnectionDraining.DrainingTimeoutSec)
+	}
+}
+
+func TestAccComputeBackendService_withConnectionDrainingAndUpdate(t *testing.T) {
+	serviceName := fmt.Sprintf("tf-test-%s", acctest.RandString(10))
+	checkName := fmt.Sprintf("tf-test-%s", acctest.RandString(10))
+	var svc compute.BackendService
+
+	resource.Test(t, resource.TestCase{
+		PreCheck:     func() { testAccPreCheck(t) },
+		Providers:    testAccProviders,
+		CheckDestroy: testAccCheckComputeBackendServiceDestroy,
+		Steps: []resource.TestStep{
+			resource.TestStep{
+				Config: testAccComputeBackendService_withConnectionDraining(serviceName, checkName, 10),
+				Check: resource.ComposeTestCheckFunc(
+					testAccCheckComputeBackendServiceExists(
+						"google_compute_backend_service.foobar", &svc),
+				),
+			},
+			resource.TestStep{
+				Config: testAccComputeBackendService_basic(serviceName, checkName),
+				Check: resource.ComposeTestCheckFunc(
+					testAccCheckComputeBackendServiceExists(
+						"google_compute_backend_service.foobar", &svc),
+				),
+			},
+		},
+	})
+
+	if svc.ConnectionDraining.DrainingTimeoutSec != 0 {
+		t.Errorf("Expected ConnectionDraining.DrainingTimeoutSec == 0, got %d", svc.ConnectionDraining.DrainingTimeoutSec)
+	}
+}
+
 func testAccCheckComputeBackendServiceDestroy(s *terraform.State) error {
 	config := testAccProvider.Meta().(*Config)
 
@@ -342,3 +399,20 @@ resource "google_compute_http_health_check" "zero" {
 }
 `, serviceName, affinityName, checkName)
 }
+
+func testAccComputeBackendService_withConnectionDraining(serviceName, checkName string, drainingTimeout int64) string {
+	return fmt.Sprintf(`
+resource "google_compute_backend_service" "foobar" {
+  name          = "%s"
+  health_checks = ["${google_compute_http_health_check.zero.self_link}"]
+  connection_draining_timeout_sec = %v
+}
+
+resource "google_compute_http_health_check" "zero" {
+  name               = "%s"
+  request_path       = "/"
+  check_interval_sec = 1
+  timeout_sec        = 1
+}
+`, serviceName, drainingTimeout, checkName)
+}

website/source/docs/providers/google/r/compute_backend_service.html.markdown

@@ -8,7 +8,9 @@ description: |-
 
 # google\_compute\_backend\_service
 
-A Backend Service defines a group of virtual machines that will serve traffic for load balancing.
+A Backend Service defines a group of virtual machines that will serve traffic for load balancing. For more information 
+see [the official documentation](https://cloud.google.com/compute/docs/load-balancing/http/backend-service)
+and the [API](https://cloud.google.com/compute/docs/reference/latest/backendServices).
 
 For internal load balancing, use a [google_compute_region_backend_service](/docs/providers/google/r/compute_region_backend_service.html).
 
@@ -72,8 +74,7 @@ The following arguments are supported:
 
 - - -
 
-* `backend` - (Optional) The list of backends that serve this BackendService.
-    See *Backend* below.
+* `backend` - (Optional) The list of backends that serve this BackendService. Structure is documented below.
 
 * `description` - (Optional) The textual description for the backend service.
 
@@ -94,8 +95,11 @@ The following arguments are supported:
 
 * `timeout_sec` - (Optional) The number of secs to wait for a backend to respond
     to a request before considering the request failed. Defaults to `30`.
+
+* `connection_draining_timeout_sec` - (Optional) Time for which instance will be drained (not accept new connections, 
+but still work to finish started ones). Defaults to `0`.
 
-**Backend** supports the following attributes:
+The `backend` block supports:
 
 * `group` - (Required) The name or URI of a Compute Engine instance group
     (`google_compute_instance_group_manager.xyz.instance_group`) that can