container_cluster: added disk_type node configuration

Added node config 'disk_type' which can either be 'pd-standard' or
'pd-ssd', if left blank 'pd-standard' will be the default used by google
cloud.

Closes: #1656

google/node_config.go

@@ -1,11 +1,12 @@
 package google
 
 import (
+	"strconv"
+	"strings"
+
 	"github.com/hashicorp/terraform/helper/schema"
 	"github.com/hashicorp/terraform/helper/validation"
 	containerBeta "google.golang.org/api/container/v1beta1"
-	"strconv"
-	"strings"
 )
 
 // Matches gke-default scope from https://cloud.google.com/sdk/gcloud/reference/container/clusters/create
@@ -34,6 +35,14 @@ var schemaNodeConfig = &schema.Schema{
 				ValidateFunc: validation.IntAtLeast(10),
 			},
 
+			"disk_type": {
+				Type:         schema.TypeString,
+				Optional:     true,
+				Computed:     true,
+				ForceNew:     true,
+				ValidateFunc: validation.StringInSlice([]string{"pd-standard", "pd-ssd"}, false),
+			},
+
 			"guest_accelerator": &schema.Schema{
 				Type:     schema.TypeList,
 				Optional: true,
@@ -216,6 +225,10 @@ func expandNodeConfig(v interface{}) *containerBeta.NodeConfig {
 		nc.DiskSizeGb = int64(v.(int))
 	}
 
+	if v, ok := nodeConfig["disk_type"]; ok {
+		nc.DiskType = v.(string)
+	}
+
 	if v, ok := nodeConfig["local_ssd_count"]; ok {
 		nc.LocalSsdCount = int64(v.(int))
 	}
@@ -304,6 +317,7 @@ func flattenNodeConfig(c *containerBeta.NodeConfig) []map[string]interface{} {
 	config = append(config, map[string]interface{}{
 		"machine_type":             c.MachineType,
 		"disk_size_gb":             c.DiskSizeGb,
+		"disk_type":                c.DiskType,
 		"guest_accelerator":        flattenContainerGuestAccelerators(c.Accelerators),
 		"local_ssd_count":          c.LocalSsdCount,
 		"service_account":          c.ServiceAccount,

google/resource_container_cluster_test.go

@@ -1631,6 +1631,7 @@ resource "google_container_cluster" "with_node_config" {
 	node_config {
 		machine_type = "n1-standard-1"
 		disk_size_gb = 15
+		disk_type = "pd-ssd"
 		local_ssd_count = 1
 		oauth_scopes = [
 			"https://www.googleapis.com/auth/monitoring",

website/docs/r/container_cluster.html.markdown

@@ -267,6 +267,9 @@ The `node_config` block supports:
 * `disk_size_gb` - (Optional) Size of the disk attached to each node, specified
     in GB. The smallest allowed disk size is 10GB. Defaults to 100GB.
 
+* `disk_type` - (Optional) Type of the disk attached to each node
+    (e.g. 'pd-standard' or 'pd-ssd'). If unspecified, the default disk type is 'pd-standard'
+
 * `guest_accelerator` - (Optional) List of the type and count of accelerator cards attached to the instance.
     Structure documented below.