[Compute_Disk] - Add beta multi-writer support (#3911)

* [Compute_Disk] - Add beta multi-writer support:

* set machine type to n2 for testcase... not supported for n1

* migrate test to disk resource

Author: ScottSuarez

products/compute/api.yaml

@@ -3274,6 +3274,11 @@ objects:
           resource: 'ResourcePolicy'
           imports: 'selfLink'
           description: 'A resource policy applied to this disk for automatic snapshot creations.'
+      - !ruby/object:Api::Type::Boolean
+        name: 'multiWriter'
+        description: |
+          Indicates whether or not the disk can be read/write attached to more than one instance.
+        min_version: beta
   - !ruby/object:Api::Resource
     name: 'Firewall'
     kind: 'compute#firewall'

third_party/terraform/tests/resource_compute_disk_test.go.erb

@@ -480,6 +480,29 @@ func TestAccComputeDisk_interface(t *testing.T) {
 }
 <% end -%>
 
+<% unless version == 'ga' -%>
+func TestAccComputeDisk_multiWriter(t *testing.T) {
+	t.Parallel()
+	instanceName := fmt.Sprintf("tf-test-%s", randString(t, 10))
+	diskName := fmt.Sprintf("tf-testd-%s", randString(t, 10))
+
+	vcrTest(t, resource.TestCase{
+		PreCheck:     func() { testAccPreCheck(t) },
+		Providers:    testAccProviders,
+		Steps: []resource.TestStep{
+			{
+				Config: testAccComputeDisk_multiWriter(instanceName, diskName, true),
+			},
+			{
+				ResourceName:      "google_compute_disk.foobar",
+				ImportState:       true,
+				ImportStateVerify: true,
+			},
+		},
+	})
+}
+<% end -%>
+
 func testAccCheckComputeDiskExists(t *testing.T, n, p string, disk *compute.Disk) resource.TestCheckFunc {
 	return func(s *terraform.State) error {
 		rs, ok := s.RootModule().Resources[n]
@@ -816,3 +839,48 @@ resource "google_compute_disk" "foobar" {
 `, diskName)
 }
 <% end -%>
+
+<% unless version == 'ga' -%>
+func testAccComputeDisk_multiWriter(instance string,  diskName string, enableMultiwriter bool) string {
+	return fmt.Sprintf(`
+data "google_compute_image" "my_image" {
+  family  = "debian-9"
+  project = "debian-cloud"
+}
+
+resource "google_compute_disk" "foobar" {
+  name         = "%s"
+  size         = 10
+  type         = "pd-ssd"
+	zone         = "us-central1-a"
+	multi_writer  = %t
+}
+
+resource "google_compute_instance" "foobar" {
+  name           = "%s"
+  machine_type   = "n2-standard-2"
+  zone           = "us-central1-a"
+  can_ip_forward = false
+	tags           = ["foo", "bar"]
+
+  boot_disk {
+    initialize_params {
+      image = data.google_compute_image.my_image.self_link
+    }
+	}
+
+	attached_disk {
+    source = google_compute_disk.foobar.name
+  }
+
+  network_interface {
+    network = "default"
+  }
+
+  metadata = {
+    foo = "bar"
+  }
+}
+`, diskName, enableMultiwriter, instance)
+}
+<% end -%>