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Merge pull request #3232 from jtopjian/openstack-bootfromvolume-image-fixes 

provider/openstack: Boot From Volume and Image Handling Fixes
This commit is contained in:
Joe Topjian 2015-11-03 13:57:18 +09:00
parent 8dd5e43673 4a5cd0b415
commit 352d6abfd7
4 changed files with 472 additions and 179 deletions
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25
builtin/providers/openstack/resource_openstack_blockstorage_volume_v1_test.go
View File

@ -8,6 +8,7 @@ import (
"github.com/hashicorp/terraform/helper/resource"
"github.com/hashicorp/terraform/terraform"
"github.com/rackspace/gophercloud"
"github.com/rackspace/gophercloud/openstack/blockstorage/v1/volumes"
)
@ -106,6 +107,30 @@ func testAccCheckBlockStorageV1VolumeExists(t *testing.T, n string, volume *volu
}
}
func testAccCheckBlockStorageV1VolumeDoesNotExist(t *testing.T, n string, volume *volumes.Volume) resource.TestCheckFunc {
return func(s *terraform.State) error {
config := testAccProvider.Meta().(*Config)
blockStorageClient, err := config.blockStorageV1Client(OS_REGION_NAME)
if err != nil {
return fmt.Errorf("Error creating OpenStack block storage client: %s", err)
}
_, err = volumes.Get(blockStorageClient, volume.ID).Extract()
if err != nil {
errCode, ok := err.(*gophercloud.UnexpectedResponseCodeError)
if !ok {
return err
}
if errCode.Actual == 404 {
return nil
}
return err
}
return fmt.Errorf("Volume still exists")
}
}
func testAccCheckBlockStorageV1VolumeMetadata(
volume *volumes.Volume, k string, v string) resource.TestCheckFunc {
return func(s *terraform.State) error {

232
builtin/providers/openstack/resource_openstack_compute_instance_v2.go
View File

@ -6,6 +6,7 @@ import (
"encoding/hex"
"fmt"
"log"
"os"
"time"
"github.com/hashicorp/terraform/helper/hashcode"
@ -49,14 +50,12 @@ func resourceComputeInstanceV2() *schema.Resource {
Optional: true,
ForceNew: true,
Computed: true,
DefaultFunc: envDefaultFunc("OS_IMAGE_ID"),
},
"image_name": &schema.Schema{
Type: schema.TypeString,
Optional: true,
ForceNew: true,
Computed: true,
DefaultFunc: envDefaultFunc("OS_IMAGE_NAME"),
},
"flavor_id": &schema.Schema{
Type: schema.TypeString,
@ -176,7 +175,12 @@ func resourceComputeInstanceV2() *schema.Resource {
ForceNew: true,
},
"block_device": &schema.Schema{
Type: schema.TypeList,
// TODO: This is a set because we don't support singleton
// sub-resources today. We'll enforce that the set only ever has
// length zero or one below. When TF gains support for
// sub-resources this can be converted.
// As referenced in resource_aws_instance.go
Type: schema.TypeSet,
Optional: true,
ForceNew: true,
Elem: &schema.Resource{
@ -201,12 +205,22 @@ func resourceComputeInstanceV2() *schema.Resource {
Type: schema.TypeInt,
Optional: true,
},
"delete_on_termination": &schema.Schema{
Type: schema.TypeBool,
Optional: true,
Default: false,
},
},
},
Set: func(v interface{}) int {
// there can only be one bootable block device; no need to hash anything
return 0
},
},
"volume": &schema.Schema{
Type: schema.TypeSet,
Optional: true,
Computed: true,
Elem: &schema.Resource{
Schema: map[string]*schema.Schema{
"id": &schema.Schema{
@ -215,7 +229,8 @@ func resourceComputeInstanceV2() *schema.Resource {
},
"volume_id": &schema.Schema{
Type: schema.TypeString,
Required: true,
Optional: true,
Computed: true,
},
"device": &schema.Schema{
Type: schema.TypeString,
@ -281,7 +296,11 @@ func resourceComputeInstanceV2Create(d *schema.ResourceData, meta interface{}) e
var createOpts servers.CreateOptsBuilder
imageId, err := getImageID(computeClient, d)
// Determines the Image ID using the following rules:
// If a bootable block_device was specified, ignore the image altogether.
// If an image_id was specified, use it.
// If an image_name was specified, look up the image ID, report if error.
imageId, err := getImageIDFromConfig(computeClient, d)
if err != nil {
return err
}
@ -296,6 +315,13 @@ func resourceComputeInstanceV2Create(d *schema.ResourceData, meta interface{}) e
return err
}
// determine if volume/block_device configuration is correct
// this includes ensuring volume_ids are set
// and if only one block_device was specified.
if err := checkVolumeConfig(d); err != nil {
return err
}
networks := make([]servers.Network, len(networkDetails))
for i, net := range networkDetails {
networks[i] = servers.Network{
@ -325,12 +351,17 @@ func resourceComputeInstanceV2Create(d *schema.ResourceData, meta interface{}) e
}
}
if blockDeviceRaw, ok := d.Get("block_device").(map[string]interface{}); ok && blockDeviceRaw != nil {
if v, ok := d.GetOk("block_device"); ok {
vL := v.(*schema.Set).List()
for _, v := range vL {
blockDeviceRaw := v.(map[string]interface{})
blockDevice := resourceInstanceBlockDeviceV2(d, blockDeviceRaw)
createOpts = &bootfromvolume.CreateOptsExt{
createOpts,
blockDevice,
}
log.Printf("[DEBUG] Create BFV Options: %+v", createOpts)
}
}
schedulerHintsRaw := d.Get("scheduler_hints").(*schema.Set).List()
@ -344,7 +375,16 @@ func resourceComputeInstanceV2Create(d *schema.ResourceData, meta interface{}) e
}
log.Printf("[DEBUG] Create Options: %#v", createOpts)
server, err := servers.Create(computeClient, createOpts).Extract()
// If a block_device is used, use the bootfromvolume.Create function as it allows an empty ImageRef.
// Otherwise, use the normal servers.Create function.
var server *servers.Server
if _, ok := d.GetOk("block_device"); ok {
server, err = bootfromvolume.Create(computeClient, createOpts).Extract()
} else {
server, err = servers.Create(computeClient, createOpts).Extract()
}
if err != nil {
return fmt.Errorf("Error creating OpenStack server: %s", err)
}
@ -381,10 +421,9 @@ func resourceComputeInstanceV2Create(d *schema.ResourceData, meta interface{}) e
}
}
// were volume attachments specified?
if v := d.Get("volume"); v != nil {
// if volumes were specified, attach them after the instance has launched.
if v, ok := d.GetOk("volume"); ok {
vols := v.(*schema.Set).List()
if len(vols) > 0 {
if blockClient, err := config.blockStorageV1Client(d.Get("region").(string)); err != nil {
return fmt.Errorf("Error creating OpenStack block storage client: %s", err)
} else {
@ -393,7 +432,6 @@ func resourceComputeInstanceV2Create(d *schema.ResourceData, meta interface{}) e
}
}
}
}
return resourceComputeInstanceV2Read(d, meta)
}
@ -528,34 +566,15 @@ func resourceComputeInstanceV2Read(d *schema.ResourceData, meta interface{}) err
}
d.Set("flavor_name", flavor.Name)
imageId, ok := server.Image["id"].(string)
if !ok {
return fmt.Errorf("Error setting OpenStack server's image: %v", server.Image)
}
d.Set("image_id", imageId)
image, err := images.Get(computeClient, imageId).Extract()
if err != nil {
// Set the instance's image information appropriately
if err := setImageInformation(computeClient, server, d); err != nil {
return err
}
d.Set("image_name", image.Name)
// volume attachments
vas, err := getVolumeAttachments(computeClient, d.Id())
if err != nil {
if err := getVolumeAttachments(computeClient, d); err != nil {
return err
}
if len(vas) > 0 {
attachments := make([]map[string]interface{}, len(vas))
for i, attachment := range vas {
attachments[i] = make(map[string]interface{})
attachments[i]["id"] = attachment.ID
attachments[i]["volume_id"] = attachment.VolumeID
attachments[i]["device"] = attachment.Device
}
log.Printf("[INFO] Volume attachments: %v", attachments)
d.Set("volume", attachments)
}
return nil
}
@ -665,12 +684,16 @@ func resourceComputeInstanceV2Update(d *schema.ResourceData, meta interface{}) e
}
if d.HasChange("volume") {
// ensure the volume configuration is correct
if err := checkVolumeConfig(d); err != nil {
return err
}
// old attachments and new attachments
oldAttachments, newAttachments := d.GetChange("volume")
// for each old attachment, detach the volume
oldAttachmentSet := oldAttachments.(*schema.Set).List()
if len(oldAttachmentSet) > 0 {
if blockClient, err := config.blockStorageV1Client(d.Get("region").(string)); err != nil {
return err
} else {
@ -678,11 +701,9 @@ func resourceComputeInstanceV2Update(d *schema.ResourceData, meta interface{}) e
return err
}
}
}
// for each new attachment, attach the volume
newAttachmentSet := newAttachments.(*schema.Set).List()
if len(newAttachmentSet) > 0 {
if blockClient, err := config.blockStorageV1Client(d.Get("region").(string)); err != nil {
return err
} else {
@ -690,7 +711,6 @@ func resourceComputeInstanceV2Update(d *schema.ResourceData, meta interface{}) e
return err
}
}
}
d.SetPartial("volume")
}
@ -924,6 +944,7 @@ func resourceInstanceBlockDeviceV2(d *schema.ResourceData, bd map[string]interfa
VolumeSize: bd["volume_size"].(int),
DestinationType: bd["destination_type"].(string),
BootIndex: bd["boot_index"].(int),
DeleteOnTermination: bd["delete_on_termination"].(bool),
},
}
@ -964,44 +985,72 @@ func resourceInstanceSchedulerHintsV2(d *schema.ResourceData, schedulerHintsRaw
return schedulerHints
}
func getImageID(client *gophercloud.ServiceClient, d *schema.ResourceData) (string, error) {
imageId := d.Get("image_id").(string)
if imageId != "" {
return imageId, nil
func getImageIDFromConfig(computeClient *gophercloud.ServiceClient, d *schema.ResourceData) (string, error) {
// If block_device was used, an Image does not need to be specified.
// If an Image was specified, ignore it
if _, ok := d.GetOk("block_device"); ok {
return "", nil
}
if imageId := d.Get("image_id").(string); imageId != "" {
return imageId, nil
} else {
// try the OS_IMAGE_ID environment variable
if v := os.Getenv("OS_IMAGE_ID"); v != "" {
return v, nil
}
}
imageCount := 0
imageName := d.Get("image_name").(string)
if imageName == "" {
// try the OS_IMAGE_NAME environment variable
if v := os.Getenv("OS_IMAGE_NAME"); v != "" {
imageName = v
}
}
if imageName != "" {
pager := images.ListDetail(client, &images.ListOpts{
Name: imageName,
})
pager.EachPage(func(page pagination.Page) (bool, error) {
imageList, err := images.ExtractImages(page)
imageId, err := images.IDFromName(computeClient, imageName)
if err != nil {
return false, err
return "", err
}
for _, i := range imageList {
if i.Name == imageName {
imageCount++
imageId = i.ID
}
}
return true, nil
})
switch imageCount {
case 0:
return "", fmt.Errorf("Unable to find image: %s", imageName)
case 1:
return imageId, nil
default:
return "", fmt.Errorf("Found %d images matching %s", imageCount, imageName)
}
return "", fmt.Errorf("Neither a boot device, image ID, or image name were able to be determined.")
}
func setImageInformation(computeClient *gophercloud.ServiceClient, server *servers.Server, d *schema.ResourceData) error {
// If block_device was used, an Image does not need to be specified.
// If an Image was specified, ignore it
if _, ok := d.GetOk("block_device"); ok {
d.Set("image_id", "Attempt to boot from volume - no image supplied")
return nil
}
imageId := server.Image["id"].(string)
if imageId != "" {
d.Set("image_id", imageId)
if image, err := images.Get(computeClient, imageId).Extract(); err != nil {
errCode, ok := err.(*gophercloud.UnexpectedResponseCodeError)
if !ok {
return err
}
if errCode.Actual == 404 {
// If the image name can't be found, set the value to "Image not found".
// The most likely scenario is that the image no longer exists in the Image Service
// but the instance still has a record from when it existed.
d.Set("image_name", "Image not found")
return nil
} else {
return err
}
} else {
d.Set("image_name", image.Name)
}
}
return "", fmt.Errorf("Neither an image ID nor an image name were able to be determined.")
return nil
}
func getFlavorID(client *gophercloud.ServiceClient, d *schema.ResourceData) (string, error) {
@ -1046,6 +1095,7 @@ func resourceComputeVolumeAttachmentHash(v interface{}) int {
var buf bytes.Buffer
m := v.(map[string]interface{})
buf.WriteString(fmt.Sprintf("%s-", m["volume_id"].(string)))
return hashcode.String(buf.String())
}
@ -1073,7 +1123,6 @@ func resourceComputeSchedulerHintsHash(v interface{}) int {
}
func attachVolumesToInstance(computeClient *gophercloud.ServiceClient, blockClient *gophercloud.ServiceClient, serverId string, vols []interface{}) error {
if len(vols) > 0 {
for _, v := range vols {
va := v.(map[string]interface{})
volumeId := va["volume_id"].(string)
@ -1112,12 +1161,10 @@ func attachVolumesToInstance(computeClient *gophercloud.ServiceClient, blockClie
log.Printf("[INFO] Attached volume %s to instance %s", volumeId, serverId)
}
}
return nil
}
func detachVolumesFromInstance(computeClient *gophercloud.ServiceClient, blockClient *gophercloud.ServiceClient, serverId string, vols []interface{}) error {
if len(vols) > 0 {
for _, v := range vols {
va := v.(map[string]interface{})
aId := va["id"].(string)
@ -1140,14 +1187,14 @@ func detachVolumesFromInstance(computeClient *gophercloud.ServiceClient, blockCl
}
log.Printf("[INFO] Detached volume %s from instance %s", va["volume_id"], serverId)
}
}
return nil
}
func getVolumeAttachments(computeClient *gophercloud.ServiceClient, serverId string) ([]volumeattach.VolumeAttachment, error) {
func getVolumeAttachments(computeClient *gophercloud.ServiceClient, d *schema.ResourceData) error {
var attachments []volumeattach.VolumeAttachment
err := volumeattach.List(computeClient, serverId).EachPage(func(page pagination.Page) (bool, error) {
err := volumeattach.List(computeClient, d.Id()).EachPage(func(page pagination.Page) (bool, error) {
actual, err := volumeattach.ExtractVolumeAttachments(page)
if err != nil {
return false, err
@ -1158,8 +1205,45 @@ func getVolumeAttachments(computeClient *gophercloud.ServiceClient, serverId str
})
if err != nil {
return nil, err
return err
}
return attachments, nil
vols := make([]map[string]interface{}, len(attachments))
for i, attachment := range attachments {
vols[i] = make(map[string]interface{})
vols[i]["id"] = attachment.ID
vols[i]["volume_id"] = attachment.VolumeID
vols[i]["device"] = attachment.Device
}
log.Printf("[INFO] Volume attachments: %v", vols)
d.Set("volume", vols)
return nil
}
func checkVolumeConfig(d *schema.ResourceData) error {
// Although a volume_id is required to attach a volume, in order to be able to report
// the attached volumes of an instance, it must be "computed" and thus "optional".
// This accounts for situations such as "boot from volume" as well as volumes being
// attached to the instance outside of Terraform.
if v := d.Get("volume"); v != nil {
vols := v.(*schema.Set).List()
if len(vols) > 0 {
for _, v := range vols {
va := v.(map[string]interface{})
if va["volume_id"].(string) == "" {
return fmt.Errorf("A volume_id must be specified when attaching volumes.")
}
}
}
}
if v, ok := d.GetOk("block_device"); ok {
vL := v.(*schema.Set).List()
if len(vL) > 1 {
return fmt.Errorf("Can only specify one block device to boot from.")
}
}
return nil
}

214
builtin/providers/openstack/resource_openstack_compute_instance_v2_test.go
View File

@ -51,6 +51,20 @@ func TestAccComputeV2Instance_volumeAttach(t *testing.T) {
var instance servers.Server
var volume volumes.Volume
var testAccComputeV2Instance_volumeAttach = fmt.Sprintf(`
resource "openstack_blockstorage_volume_v1" "myvol" {
name = "myvol"
size = 1
}
resource "openstack_compute_instance_v2" "foo" {
name = "terraform-test"
security_groups = ["default"]
volume {
volume_id = "${openstack_blockstorage_volume_v1.myvol.id}"
}
}`)
resource.Test(t, resource.TestCase{
PreCheck: func() { testAccPreCheck(t) },
Providers: testAccProviders,
@ -68,6 +82,102 @@ func TestAccComputeV2Instance_volumeAttach(t *testing.T) {
})
}
func TestAccComputeV2Instance_volumeAttachPostCreation(t *testing.T) {
var instance servers.Server
var volume volumes.Volume
var testAccComputeV2Instance_volumeAttachPostCreationInstance = fmt.Sprintf(`
resource "openstack_compute_instance_v2" "foo" {
name = "terraform-test"
security_groups = ["default"]
}`)
var testAccComputeV2Instance_volumeAttachPostCreationInstanceAndVolume = fmt.Sprintf(`
resource "openstack_blockstorage_volume_v1" "myvol" {
name = "myvol"
size = 1
}
resource "openstack_compute_instance_v2" "foo" {
name = "terraform-test"
security_groups = ["default"]
volume {
volume_id = "${openstack_blockstorage_volume_v1.myvol.id}"
}
}`)
resource.Test(t, resource.TestCase{
PreCheck: func() { testAccPreCheck(t) },
Providers: testAccProviders,
CheckDestroy: testAccCheckComputeV2InstanceDestroy,
Steps: []resource.TestStep{
resource.TestStep{
Config: testAccComputeV2Instance_volumeAttachPostCreationInstance,
Check: resource.ComposeTestCheckFunc(
testAccCheckComputeV2InstanceExists(t, "openstack_compute_instance_v2.foo", &instance),
),
},
resource.TestStep{
Config: testAccComputeV2Instance_volumeAttachPostCreationInstanceAndVolume,
Check: resource.ComposeTestCheckFunc(
testAccCheckBlockStorageV1VolumeExists(t, "openstack_blockstorage_volume_v1.myvol", &volume),
testAccCheckComputeV2InstanceExists(t, "openstack_compute_instance_v2.foo", &instance),
testAccCheckComputeV2InstanceVolumeAttachment(&instance, &volume),
),
},
},
})
}
func TestAccComputeV2Instance_volumeDetachPostCreation(t *testing.T) {
var instance servers.Server
var volume volumes.Volume
var testAccComputeV2Instance_volumeDetachPostCreationInstanceAndVolume = fmt.Sprintf(`
resource "openstack_blockstorage_volume_v1" "myvol" {
name = "myvol"
size = 1
}
resource "openstack_compute_instance_v2" "foo" {
name = "terraform-test"
security_groups = ["default"]
volume {
volume_id = "${openstack_blockstorage_volume_v1.myvol.id}"
}
}`)
var testAccComputeV2Instance_volumeDetachPostCreationInstance = fmt.Sprintf(`
resource "openstack_compute_instance_v2" "foo" {
name = "terraform-test"
security_groups = ["default"]
}`)
resource.Test(t, resource.TestCase{
PreCheck: func() { testAccPreCheck(t) },
Providers: testAccProviders,
CheckDestroy: testAccCheckComputeV2InstanceDestroy,
Steps: []resource.TestStep{
resource.TestStep{
Config: testAccComputeV2Instance_volumeDetachPostCreationInstanceAndVolume,
Check: resource.ComposeTestCheckFunc(
testAccCheckBlockStorageV1VolumeExists(t, "openstack_blockstorage_volume_v1.myvol", &volume),
testAccCheckComputeV2InstanceExists(t, "openstack_compute_instance_v2.foo", &instance),
testAccCheckComputeV2InstanceVolumeAttachment(&instance, &volume),
),
},
resource.TestStep{
Config: testAccComputeV2Instance_volumeDetachPostCreationInstance,
Check: resource.ComposeTestCheckFunc(
testAccCheckBlockStorageV1VolumeDoesNotExist(t, "openstack_blockstorage_volume_v1.myvol", &volume),
testAccCheckComputeV2InstanceExists(t, "openstack_compute_instance_v2.foo", &instance),
testAccCheckComputeV2InstanceVolumesDetached(&instance),
),
},
},
})
}
func TestAccComputeV2Instance_floatingIPAttach(t *testing.T) {
var instance servers.Server
var fip floatingip.FloatingIP
@ -143,6 +253,39 @@ func TestAccComputeV2Instance_multi_secgroups(t *testing.T) {
})
}
func TestAccComputeV2Instance_bootFromVolume(t *testing.T) {
var instance servers.Server
var testAccComputeV2Instance_bootFromVolume = fmt.Sprintf(`
resource "openstack_compute_instance_v2" "foo" {
name = "terraform-test"
security_groups = ["default"]
block_device {
uuid = "%s"
source_type = "image"
volume_size = 5
boot_index = 0
destination_type = "volume"
delete_on_termination = true
}
}`,
os.Getenv("OS_IMAGE_ID"))
resource.Test(t, resource.TestCase{
PreCheck: func() { testAccPreCheck(t) },
Providers: testAccProviders,
CheckDestroy: testAccCheckComputeV2InstanceDestroy,
Steps: []resource.TestStep{
resource.TestStep{
Config: testAccComputeV2Instance_bootFromVolume,
Check: resource.ComposeTestCheckFunc(
testAccCheckComputeV2InstanceExists(t, "openstack_compute_instance_v2.foo", &instance),
testAccCheckComputeV2InstanceBootVolumeAttachment(&instance),
),
},
},
})
}
func testAccCheckComputeV2InstanceDestroy(s *terraform.State) error {
config := testAccProvider.Meta().(*Config)
computeClient, err := config.computeV2Client(OS_REGION_NAME)
@ -249,6 +392,61 @@ func testAccCheckComputeV2InstanceVolumeAttachment(
}
}
func testAccCheckComputeV2InstanceVolumesDetached(instance *servers.Server) resource.TestCheckFunc {
return func(s *terraform.State) error {
var attachments []volumeattach.VolumeAttachment
config := testAccProvider.Meta().(*Config)
computeClient, err := config.computeV2Client(OS_REGION_NAME)
if err != nil {
return err
}
err = volumeattach.List(computeClient, instance.ID).EachPage(func(page pagination.Page) (bool, error) {
actual, err := volumeattach.ExtractVolumeAttachments(page)
if err != nil {
return false, fmt.Errorf("Unable to lookup attachment: %s", err)
}
attachments = actual
return true, nil
})
if len(attachments) > 0 {
return fmt.Errorf("Volumes are still attached.")
}
return nil
}
}
func testAccCheckComputeV2InstanceBootVolumeAttachment(
instance *servers.Server) resource.TestCheckFunc {
return func(s *terraform.State) error {
var attachments []volumeattach.VolumeAttachment
config := testAccProvider.Meta().(*Config)
computeClient, err := config.computeV2Client(OS_REGION_NAME)
if err != nil {
return err
}
err = volumeattach.List(computeClient, instance.ID).EachPage(func(page pagination.Page) (bool, error) {
actual, err := volumeattach.ExtractVolumeAttachments(page)
if err != nil {
return false, fmt.Errorf("Unable to lookup attachment: %s", err)
}
attachments = actual
return true, nil
})
if len(attachments) == 1 {
return nil
}
return fmt.Errorf("No attached volume found.")
}
}
func testAccCheckComputeV2InstanceFloatingIPAttach(
instance *servers.Server, fip *floatingip.FloatingIP) resource.TestCheckFunc {
return func(s *terraform.State) error {
@ -260,19 +458,3 @@ func testAccCheckComputeV2InstanceFloatingIPAttach(
}
}
var testAccComputeV2Instance_volumeAttach = fmt.Sprintf(`
resource "openstack_blockstorage_volume_v1" "myvol" {
name = "myvol"
size = 1
}
resource "openstack_compute_instance_v2" "foo" {
region = "%s"
name = "terraform-test"
security_groups = ["default"]
volume {
volume_id = "${openstack_blockstorage_volume_v1.myvol.id}"
}
}`,
OS_REGION_NAME)

10
website/source/docs/providers/openstack/r/compute_instance_v2.html.markdown
View File

@ -35,11 +35,13 @@ The following arguments are supported:
* `name` - (Required) A unique name for the resource.
* `image_id` - (Optional; Required if `image_name` is empty) The image ID of
the desired image for the server. Changing this creates a new server.
* `image_id` - (Optional; Required if `image_name` is empty and not booting
from a volume) The image ID of the desired image for the server. Changing
this creates a new server.
* `image_name` - (Optional; Required if `image_id` is empty) The name of the
desired image for the server. Changing this creates a new server.
* `image_name` - (Optional; Required if `image_id` is empty and not booting
from a volume) The name of the desired image for the server. Changing this
creates a new server.
* `flavor_id` - (Optional; Required if `flavor_name` is empty) The flavor ID of
the desired flavor for the server. Changing this resizes the existing server.