builder/googlecompute: accept disk type, default pd-standard

builder/googlecompute/config.go

@@ -25,6 +25,7 @@ type Config struct {
 
 	DiskName             string            `mapstructure:"disk_name"`
 	DiskSizeGb           int64             `mapstructure:"disk_size"`
+	DiskType             string            `mapstructure:"disk_type"`
 	ImageName            string            `mapstructure:"image_name"`
 	ImageDescription     string            `mapstructure:"image_description"`
 	InstanceName         string            `mapstructure:"instance_name"`
@@ -70,6 +71,10 @@ func NewConfig(raws ...interface{}) (*Config, []string, error) {
 		c.DiskSizeGb = 10
 	}
 
+	if c.DiskType == "" {
+		c.DiskType = "pd-standard"
+	}
+
 	if c.ImageDescription == "" {
 		c.ImageDescription = "Created by Packer"
 	}

builder/googlecompute/driver.go

@@ -42,6 +42,7 @@ type Image struct {
 type InstanceConfig struct {
 	Description string
 	DiskSizeGb  int64
+	DiskType    string
 	Image       Image
 	MachineType string
 	Metadata    map[string]string

builder/googlecompute/driver_gce.go

@@ -236,6 +236,7 @@ func (d *driverGCE) RunInstance(c *InstanceConfig) (<-chan error, error) {
 				InitializeParams: &compute.AttachedDiskInitializeParams{
 					SourceImage: image.SelfLink,
 					DiskSizeGb:  c.DiskSizeGb,
+					DiskType:    fmt.Sprintf("zones/%s/diskTypes/%s", zone.Name, c.DiskType),
 				},
 			},
 		},

builder/googlecompute/step_create_instance.go

@@ -54,6 +54,7 @@ func (s *StepCreateInstance) Run(state multistep.StateBag) multistep.StepAction
 	errCh, err := driver.RunInstance(&InstanceConfig{
 		Description: "New instance created by Packer",
 		DiskSizeGb:  config.DiskSizeGb,
+		DiskType:    config.DiskType,
 		Image:       config.getImage(),
 		MachineType: config.MachineType,
 		Metadata:    config.getInstanceMetadata(sshPublicKey),