Merge pull request #1045 from hashicorp/f-block-devices

providers/aws: rework instance block devices

builtin/providers/aws/resource_aws_instance.go

@@ -24,6 +24,9 @@ func resourceAwsInstance() *schema.Resource {
 		Update: resourceAwsInstanceUpdate,
 		Delete: resourceAwsInstanceDelete,
 
+		SchemaVersion: 1,
+		MigrateState:  resourceAwsInstanceMigrateState,
+
 		Schema: map[string]*schema.Schema{
 			"ami": &schema.Schema{
 				Type:     schema.TypeString,
@@ -127,53 +130,28 @@ func resourceAwsInstance() *schema.Resource {
 				ForceNew: true,
 				Optional: true,
 			},
+
 			"tenancy": &schema.Schema{
 				Type:     schema.TypeString,
 				Optional: true,
 				Computed: true,
 				ForceNew: true,
 			},
+
 			"tags": tagsSchema(),
 
 			"block_device": &schema.Schema{
+				Type:     schema.TypeMap,
+				Optional: true,
+				Removed:  "Split out into three sub-types; see Changelog and Docs",
+			},
+
+			"ebs_block_device": &schema.Schema{
 				Type:     schema.TypeSet,
 				Optional: true,
 				Computed: true,
 				Elem: &schema.Resource{
 					Schema: map[string]*schema.Schema{
-						"device_name": &schema.Schema{
-							Type:     schema.TypeString,
-							Required: true,
-							ForceNew: true,
-						},
-
-						"virtual_name": &schema.Schema{
-							Type:     schema.TypeString,
-							Optional: true,
-							ForceNew: true,
-						},
-
-						"snapshot_id": &schema.Schema{
-							Type:     schema.TypeString,
-							Optional: true,
-							Computed: true,
-							ForceNew: true,
-						},
-
-						"volume_type": &schema.Schema{
-							Type:     schema.TypeString,
-							Optional: true,
-							Computed: true,
-							ForceNew: true,
-						},
-
-						"volume_size": &schema.Schema{
-							Type:     schema.TypeInt,
-							Optional: true,
-							Computed: true,
-							ForceNew: true,
-						},
-
 						"delete_on_termination": &schema.Schema{
 							Type:     schema.TypeBool,
 							Optional: true,
@@ -181,6 +159,12 @@ func resourceAwsInstance() *schema.Resource {
 							ForceNew: true,
 						},
 
+						"device_name": &schema.Schema{
+							Type:     schema.TypeString,
+							Required: true,
+							ForceNew: true,
+						},
+
 						"encrypted": &schema.Schema{
 							Type:     schema.TypeBool,
 							Optional: true,
@@ -194,17 +178,79 @@ func resourceAwsInstance() *schema.Resource {
 							Computed: true,
 							ForceNew: true,
 						},
+
+						"snapshot_id": &schema.Schema{
+							Type:     schema.TypeString,
+							Optional: true,
+							Computed: true,
+							ForceNew: true,
+						},
+
+						"volume_size": &schema.Schema{
+							Type:     schema.TypeInt,
+							Optional: true,
+							Computed: true,
+							ForceNew: true,
+						},
+
+						"volume_type": &schema.Schema{
+							Type:     schema.TypeString,
+							Optional: true,
+							Computed: true,
+							ForceNew: true,
+						},
 					},
 				},
-				Set: resourceAwsInstanceBlockDevicesHash,
+				Set: func(v interface{}) int {
+					var buf bytes.Buffer
+					m := v.(map[string]interface{})
+					buf.WriteString(fmt.Sprintf("%t-", m["delete_on_termination"].(bool)))
+					buf.WriteString(fmt.Sprintf("%s-", m["device_name"].(string)))
+					buf.WriteString(fmt.Sprintf("%t-", m["encrypted"].(bool)))
+					// NOTE: Not considering IOPS in hash; when using gp2, IOPS can come
+					// back set to something like "33", which throws off the set
+					// calculation and generates an unresolvable diff.
+					// buf.WriteString(fmt.Sprintf("%d-", m["iops"].(int)))
+					buf.WriteString(fmt.Sprintf("%s-", m["snapshot_id"].(string)))
+					buf.WriteString(fmt.Sprintf("%d-", m["volume_size"].(int)))
+					buf.WriteString(fmt.Sprintf("%s-", m["volume_type"].(string)))
+					return hashcode.String(buf.String())
+				},
+			},
+
+			"ephemeral_block_device": &schema.Schema{
+				Type:     schema.TypeSet,
+				Optional: true,
+				Computed: true,
+				ForceNew: true,
+				Elem: &schema.Resource{
+					Schema: map[string]*schema.Schema{
+						"device_name": &schema.Schema{
+							Type:     schema.TypeString,
+							Required: true,
+						},
+
+						"virtual_name": &schema.Schema{
+							Type:     schema.TypeString,
+							Required: true,
+						},
+					},
+				},
+				Set: func(v interface{}) int {
+					var buf bytes.Buffer
+					m := v.(map[string]interface{})
+					buf.WriteString(fmt.Sprintf("%s-", m["device_name"].(string)))
+					buf.WriteString(fmt.Sprintf("%s-", m["virtual_name"].(string)))
+					return hashcode.String(buf.String())
+				},
 			},
 
 			"root_block_device": &schema.Schema{
-				// TODO: This is a list because we don't support singleton
+				// TODO: This is a set because we don't support singleton
-				//       sub-resources today. We'll enforce that the list only ever has
+				//       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.
-				Type:     schema.TypeList,
+				Type:     schema.TypeSet,
 				Optional: true,
 				Computed: true,
 				Elem: &schema.Resource{
@@ -226,6 +272,13 @@ func resourceAwsInstance() *schema.Resource {
 							Default:  "/dev/sda1",
 						},
 
+						"iops": &schema.Schema{
+							Type:     schema.TypeInt,
+							Optional: true,
+							Computed: true,
+							ForceNew: true,
+						},
+
 						"volume_size": &schema.Schema{
 							Type:     schema.TypeInt,
 							Optional: true,
@@ -239,15 +292,19 @@ func resourceAwsInstance() *schema.Resource {
 							Computed: true,
 							ForceNew: true,
 						},
-
-						"iops": &schema.Schema{
-							Type:     schema.TypeInt,
-							Optional: true,
-							Computed: true,
-							ForceNew: true,
-						},
 					},
 				},
+				Set: func(v interface{}) int {
+					var buf bytes.Buffer
+					m := v.(map[string]interface{})
+					buf.WriteString(fmt.Sprintf("%t-", m["delete_on_termination"].(bool)))
+					buf.WriteString(fmt.Sprintf("%s-", m["device_name"].(string)))
+					// See the NOTE in "ebs_block_device" for why we skip iops here.
+					// buf.WriteString(fmt.Sprintf("%d-", m["iops"].(int)))
+					buf.WriteString(fmt.Sprintf("%d-", m["volume_size"].(int)))
+					buf.WriteString(fmt.Sprintf("%s-", m["volume_type"].(string)))
+					return hashcode.String(buf.String())
+				},
 			},
 		},
 	}
@@ -349,46 +406,87 @@ func resourceAwsInstanceCreate(d *schema.ResourceData, meta interface{}) error {
 		runOpts.KeyName = aws.String(v.(string))
 	}
 
-	blockDevices := make([]interface{}, 0)
+	blockDevices := make([]ec2.BlockDeviceMapping, 0)
 
-	if v := d.Get("block_device"); v != nil {
+	if v, ok := d.GetOk("ebs_block_device"); ok {
-		blockDevices = append(blockDevices, v.(*schema.Set).List()...)
+		vL := v.(*schema.Set).List()
-	}
+		for _, v := range vL {
-
-	if v := d.Get("root_block_device"); v != nil {
-		rootBlockDevices := v.([]interface{})
-		if len(rootBlockDevices) > 1 {
-			return fmt.Errorf("Cannot specify more than one root_block_device.")
-		}
-		blockDevices = append(blockDevices, rootBlockDevices...)
-	}
-
-	if len(blockDevices) > 0 {
-		runOpts.BlockDeviceMappings = make([]ec2.BlockDeviceMapping, len(blockDevices))
-		for i, v := range blockDevices {
 			bd := v.(map[string]interface{})
-			runOpts.BlockDeviceMappings[i].DeviceName = aws.String(bd["device_name"].(string))
+			ebs := &ec2.EBSBlockDevice{
-			runOpts.BlockDeviceMappings[i].EBS = &ec2.EBSBlockDevice{
-				VolumeType:          aws.String(bd["volume_type"].(string)),
-				VolumeSize:          aws.Integer(bd["volume_size"].(int)),
 				DeleteOnTermination: aws.Boolean(bd["delete_on_termination"].(bool)),
 			}
 
-			if v, ok := bd["virtual_name"].(string); ok {
-				runOpts.BlockDeviceMappings[i].VirtualName = aws.String(v)
-			}
 			if v, ok := bd["snapshot_id"].(string); ok && v != "" {
-				runOpts.BlockDeviceMappings[i].EBS.SnapshotID = aws.String(v)
+				ebs.SnapshotID = aws.String(v)
 			}
-			if v, ok := bd["encrypted"].(bool); ok {
+
-				runOpts.BlockDeviceMappings[i].EBS.Encrypted = aws.Boolean(v)
+			if v, ok := bd["volume_size"].(int); ok && v != 0 {
+				ebs.VolumeSize = aws.Integer(v)
 			}
+
+			if v, ok := bd["volume_type"].(string); ok && v != "" {
+				ebs.VolumeType = aws.String(v)
+			}
+
 			if v, ok := bd["iops"].(int); ok && v > 0 {
-				runOpts.BlockDeviceMappings[i].EBS.IOPS = aws.Integer(v)
+				ebs.IOPS = aws.Integer(v)
 			}
+
+			blockDevices = append(blockDevices, ec2.BlockDeviceMapping{
+				DeviceName: aws.String(bd["device_name"].(string)),
+				EBS:        ebs,
+			})
 		}
 	}
 
+	if v, ok := d.GetOk("ephemeral_block_device"); ok {
+		vL := v.(*schema.Set).List()
+		for _, v := range vL {
+			bd := v.(map[string]interface{})
+			blockDevices = append(blockDevices, ec2.BlockDeviceMapping{
+				DeviceName:  aws.String(bd["device_name"].(string)),
+				VirtualName: aws.String(bd["virtual_name"].(string)),
+			})
+		}
+		// if err := d.Set("ephemeral_block_device", vL); err != nil {
+		// 	return err
+		// }
+	}
+
+	if v, ok := d.GetOk("root_block_device"); ok {
+		vL := v.(*schema.Set).List()
+		if len(vL) > 1 {
+			return fmt.Errorf("Cannot specify more than one root_block_device.")
+		}
+		for _, v := range vL {
+			bd := v.(map[string]interface{})
+			ebs := &ec2.EBSBlockDevice{
+				DeleteOnTermination: aws.Boolean(bd["delete_on_termination"].(bool)),
+			}
+
+			if v, ok := bd["volume_size"].(int); ok && v != 0 {
+				ebs.VolumeSize = aws.Integer(v)
+			}
+
+			if v, ok := bd["volume_type"].(string); ok && v != "" {
+				ebs.VolumeType = aws.String(v)
+			}
+
+			if v, ok := bd["iops"].(int); ok && v > 0 {
+				ebs.IOPS = aws.Integer(v)
+			}
+
+			blockDevices = append(blockDevices, ec2.BlockDeviceMapping{
+				DeviceName: aws.String(bd["device_name"].(string)),
+				EBS:        ebs,
+			})
+		}
+	}
+
+	if len(blockDevices) > 0 {
+		runOpts.BlockDeviceMappings = blockDevices
+	}
+
 	// Create the instance
 	log.Printf("[DEBUG] Run configuration: %#v", runOpts)
 	runResp, err := ec2conn.RunInstances(runOpts)
@@ -520,50 +618,10 @@ func resourceAwsInstanceRead(d *schema.ResourceData, meta interface{}) error {
 	}
 	d.Set("security_groups", sgs)
 
-	blockDevices := make(map[string]ec2.InstanceBlockDeviceMapping)
+	if err := readBlockDevices(d, instance, ec2conn); err != nil {
-	for _, bd := range instance.BlockDeviceMappings {
-		blockDevices[*bd.EBS.VolumeID] = bd
-	}
-
-	volIDs := make([]string, 0, len(blockDevices))
-	for _, vol := range blockDevices {
-		volIDs = append(volIDs, *vol.EBS.VolumeID)
-	}
-
-	volResp, err := ec2conn.DescribeVolumes(&ec2.DescribeVolumesRequest{
-		VolumeIDs: volIDs,
-	})
-	if err != nil {
 		return err
 	}
 
-	nonRootBlockDevices := make([]map[string]interface{}, 0)
-	rootBlockDevice := make([]interface{}, 0, 1)
-	for _, vol := range volResp.Volumes {
-		blockDevice := make(map[string]interface{})
-		blockDevice["device_name"] = *blockDevices[*vol.VolumeID].DeviceName
-		blockDevice["volume_type"] = *vol.VolumeType
-		blockDevice["volume_size"] = *vol.Size
-		if vol.IOPS != nil {
-			blockDevice["iops"] = *vol.IOPS
-		}
-		blockDevice["delete_on_termination"] =
-			*blockDevices[*vol.VolumeID].EBS.DeleteOnTermination
-
-		// If this is the root device, save it. We stop here since we
-		// can't put invalid keys into this map.
-		if blockDevice["device_name"] == *instance.RootDeviceName {
-			rootBlockDevice = []interface{}{blockDevice}
-			continue
-		}
-
-		blockDevice["snapshot_id"] = *vol.SnapshotID
-		blockDevice["encrypted"] = *vol.Encrypted
-		nonRootBlockDevices = append(nonRootBlockDevices, blockDevice)
-	}
-	d.Set("block_device", nonRootBlockDevices)
-	d.Set("root_block_device", rootBlockDevice)
-
 	return nil
 }
 
@@ -659,11 +717,89 @@ func InstanceStateRefreshFunc(conn *ec2.EC2, instanceID string) resource.StateRe
 	}
 }
 
-func resourceAwsInstanceBlockDevicesHash(v interface{}) int {
+func readBlockDevices(d *schema.ResourceData, instance *ec2.Instance, ec2conn *ec2.EC2) error {
-	var buf bytes.Buffer
+	ibds, err := readBlockDevicesFromInstance(instance, ec2conn)
-	m := v.(map[string]interface{})
+	if err != nil {
-	buf.WriteString(fmt.Sprintf("%s-", m["device_name"].(string)))
+		return err
-	buf.WriteString(fmt.Sprintf("%s-", m["virtual_name"].(string)))
+	}
-	buf.WriteString(fmt.Sprintf("%t-", m["delete_on_termination"].(bool)))
+
-	return hashcode.String(buf.String())
+	if err := d.Set("ebs_block_device", ibds["ebs"]); err != nil {
+		return err
+	}
+	if ibds["root"] != nil {
+		if err := d.Set("root_block_device", []interface{}{ibds["root"]}); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func readBlockDevicesFromInstance(instance *ec2.Instance, ec2conn *ec2.EC2) (map[string]interface{}, error) {
+	blockDevices := make(map[string]interface{})
+	blockDevices["ebs"] = make([]map[string]interface{}, 0)
+	blockDevices["root"] = nil
+
+	instanceBlockDevices := make(map[string]ec2.InstanceBlockDeviceMapping)
+	for _, bd := range instance.BlockDeviceMappings {
+		if bd.EBS != nil {
+			instanceBlockDevices[*(bd.EBS.VolumeID)] = bd
+		}
+	}
+
+	volIDs := make([]string, 0, len(instanceBlockDevices))
+	for volID := range instanceBlockDevices {
+		volIDs = append(volIDs, volID)
+	}
+
+	// Need to call DescribeVolumes to get volume_size and volume_type for each
+	// EBS block device
+	volResp, err := ec2conn.DescribeVolumes(&ec2.DescribeVolumesRequest{
+		VolumeIDs: volIDs,
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	for _, vol := range volResp.Volumes {
+		instanceBd := instanceBlockDevices[*vol.VolumeID]
+		bd := make(map[string]interface{})
+
+		if instanceBd.EBS != nil && instanceBd.EBS.DeleteOnTermination != nil {
+			bd["delete_on_termination"] = *instanceBd.EBS.DeleteOnTermination
+		}
+		if instanceBd.DeviceName != nil {
+			bd["device_name"] = *instanceBd.DeviceName
+		}
+		if vol.Size != nil {
+			bd["volume_size"] = *vol.Size
+		}
+		if vol.VolumeType != nil {
+			bd["volume_type"] = *vol.VolumeType
+		}
+		if vol.IOPS != nil {
+			bd["iops"] = *vol.IOPS
+		}
+
+		if blockDeviceIsRoot(instanceBd, instance) {
+			blockDevices["root"] = bd
+		} else {
+			if vol.Encrypted != nil {
+				bd["encrypted"] = *vol.Encrypted
+			}
+			if vol.SnapshotID != nil {
+				bd["snapshot_id"] = *vol.SnapshotID
+			}
+
+			blockDevices["ebs"] = append(blockDevices["ebs"].([]map[string]interface{}), bd)
+		}
+	}
+
+	return blockDevices, nil
+}
+
+func blockDeviceIsRoot(bd ec2.InstanceBlockDeviceMapping, instance *ec2.Instance) bool {
+	return (bd.DeviceName != nil &&
+		instance.RootDeviceName != nil &&
+		*bd.DeviceName == *instance.RootDeviceName)
 }

builtin/providers/aws/resource_aws_instance_migrate.go

@@ -0,0 +1,107 @@
+package aws
+
+import (
+	"fmt"
+	"log"
+	"strconv"
+	"strings"
+
+	"github.com/hashicorp/terraform/helper/hashcode"
+	"github.com/hashicorp/terraform/terraform"
+)
+
+func resourceAwsInstanceMigrateState(
+	v int, is *terraform.InstanceState, meta interface{}) (*terraform.InstanceState, error) {
+	switch v {
+	case 0:
+		log.Println("[INFO] Found AWS Instance State v0; migrating to v1")
+		return migrateStateV0toV1(is)
+	default:
+		return is, fmt.Errorf("Unexpected schema version: %d", v)
+	}
+
+	return is, nil
+}
+
+func migrateStateV0toV1(is *terraform.InstanceState) (*terraform.InstanceState, error) {
+	log.Printf("[DEBUG] Attributes before migration: %#v", is.Attributes)
+	// Delete old count
+	delete(is.Attributes, "block_device.#")
+
+	oldBds, err := readV0BlockDevices(is)
+	if err != nil {
+		return is, err
+	}
+	// seed count fields for new types
+	is.Attributes["ebs_block_device.#"] = "0"
+	is.Attributes["ephemeral_block_device.#"] = "0"
+	// depending on if state was v0.3.7 or an earlier version, it might have
+	// root_block_device defined already
+	if _, ok := is.Attributes["root_block_device.#"]; !ok {
+		is.Attributes["root_block_device.#"] = "0"
+	}
+	for _, oldBd := range oldBds {
+		if err := writeV1BlockDevice(is, oldBd); err != nil {
+			return is, err
+		}
+	}
+	log.Printf("[DEBUG] Attributes after migration: %#v", is.Attributes)
+	return is, nil
+}
+
+func readV0BlockDevices(is *terraform.InstanceState) (map[string]map[string]string, error) {
+	oldBds := make(map[string]map[string]string)
+	for k, v := range is.Attributes {
+		if !strings.HasPrefix(k, "block_device.") {
+			continue
+		}
+		path := strings.Split(k, ".")
+		if len(path) != 3 {
+			return oldBds, fmt.Errorf("Found unexpected block_device field: %#v", k)
+		}
+		hashcode, attribute := path[1], path[2]
+		oldBd, ok := oldBds[hashcode]
+		if !ok {
+			oldBd = make(map[string]string)
+			oldBds[hashcode] = oldBd
+		}
+		oldBd[attribute] = v
+		delete(is.Attributes, k)
+	}
+	return oldBds, nil
+}
+
+func writeV1BlockDevice(
+	is *terraform.InstanceState, oldBd map[string]string) error {
+	code := hashcode.String(oldBd["device_name"])
+	bdType := "ebs_block_device"
+	if vn, ok := oldBd["virtual_name"]; ok && strings.HasPrefix(vn, "ephemeral") {
+		bdType = "ephemeral_block_device"
+	} else if dn, ok := oldBd["device_name"]; ok && dn == "/dev/sda1" {
+		bdType = "root_block_device"
+	}
+
+	switch bdType {
+	case "ebs_block_device":
+		delete(oldBd, "virtual_name")
+	case "root_block_device":
+		delete(oldBd, "virtual_name")
+		delete(oldBd, "encrypted")
+		delete(oldBd, "snapshot_id")
+	case "ephemeral_block_device":
+		delete(oldBd, "delete_on_termination")
+		delete(oldBd, "encrypted")
+		delete(oldBd, "iops")
+		delete(oldBd, "volume_size")
+		delete(oldBd, "volume_type")
+	}
+	for attr, val := range oldBd {
+		attrKey := fmt.Sprintf("%s.%d.%s", bdType, code, attr)
+		is.Attributes[attrKey] = val
+	}
+
+	countAttr := fmt.Sprintf("%s.#", bdType)
+	count, _ := strconv.Atoi(is.Attributes[countAttr])
+	is.Attributes[countAttr] = strconv.Itoa(count + 1)
+	return nil
+}

builtin/providers/aws/resource_aws_instance_migrate_test.go

@@ -0,0 +1,135 @@
+package aws
+
+import (
+	"testing"
+
+	"github.com/hashicorp/terraform/terraform"
+)
+
+func TestAWSInstanceMigrateState(t *testing.T) {
+	cases := map[string]struct {
+		StateVersion int
+		Attributes   map[string]string
+		Expected     map[string]string
+		Meta         interface{}
+	}{
+		"v0.3.6 and earlier": {
+			StateVersion: 0,
+			Attributes: map[string]string{
+				// EBS
+				"block_device.#":                                "2",
+				"block_device.3851383343.delete_on_termination": "true",
+				"block_device.3851383343.device_name":           "/dev/sdx",
+				"block_device.3851383343.encrypted":             "false",
+				"block_device.3851383343.snapshot_id":           "",
+				"block_device.3851383343.virtual_name":          "",
+				"block_device.3851383343.volume_size":           "5",
+				"block_device.3851383343.volume_type":           "standard",
+				// Ephemeral
+				"block_device.3101711606.delete_on_termination": "false",
+				"block_device.3101711606.device_name":           "/dev/sdy",
+				"block_device.3101711606.encrypted":             "false",
+				"block_device.3101711606.snapshot_id":           "",
+				"block_device.3101711606.virtual_name":          "ephemeral0",
+				"block_device.3101711606.volume_size":           "",
+				"block_device.3101711606.volume_type":           "",
+				// Root
+				"block_device.56575650.delete_on_termination": "true",
+				"block_device.56575650.device_name":           "/dev/sda1",
+				"block_device.56575650.encrypted":             "false",
+				"block_device.56575650.snapshot_id":           "",
+				"block_device.56575650.volume_size":           "10",
+				"block_device.56575650.volume_type":           "standard",
+			},
+			Expected: map[string]string{
+				"ebs_block_device.#":                                 "1",
+				"ebs_block_device.3851383343.delete_on_termination":  "true",
+				"ebs_block_device.3851383343.device_name":            "/dev/sdx",
+				"ebs_block_device.3851383343.encrypted":              "false",
+				"ebs_block_device.3851383343.snapshot_id":            "",
+				"ebs_block_device.3851383343.volume_size":            "5",
+				"ebs_block_device.3851383343.volume_type":            "standard",
+				"ephemeral_block_device.#":                           "1",
+				"ephemeral_block_device.2458403513.device_name":      "/dev/sdy",
+				"ephemeral_block_device.2458403513.virtual_name":     "ephemeral0",
+				"root_block_device.#":                                "1",
+				"root_block_device.3018388612.delete_on_termination": "true",
+				"root_block_device.3018388612.device_name":           "/dev/sda1",
+				"root_block_device.3018388612.snapshot_id":           "",
+				"root_block_device.3018388612.volume_size":           "10",
+				"root_block_device.3018388612.volume_type":           "standard",
+			},
+		},
+		"v0.3.7": {
+			StateVersion: 0,
+			Attributes: map[string]string{
+				// EBS
+				"block_device.#":                                "2",
+				"block_device.3851383343.delete_on_termination": "true",
+				"block_device.3851383343.device_name":           "/dev/sdx",
+				"block_device.3851383343.encrypted":             "false",
+				"block_device.3851383343.snapshot_id":           "",
+				"block_device.3851383343.virtual_name":          "",
+				"block_device.3851383343.volume_size":           "5",
+				"block_device.3851383343.volume_type":           "standard",
+				"block_device.3851383343.iops":                  "",
+				// Ephemeral
+				"block_device.3101711606.delete_on_termination": "false",
+				"block_device.3101711606.device_name":           "/dev/sdy",
+				"block_device.3101711606.encrypted":             "false",
+				"block_device.3101711606.snapshot_id":           "",
+				"block_device.3101711606.virtual_name":          "ephemeral0",
+				"block_device.3101711606.volume_size":           "",
+				"block_device.3101711606.volume_type":           "",
+				"block_device.3101711606.iops":                  "",
+				// Root
+				"root_block_device.#":                                "1",
+				"root_block_device.3018388612.delete_on_termination": "true",
+				"root_block_device.3018388612.device_name":           "/dev/sda1",
+				"root_block_device.3018388612.snapshot_id":           "",
+				"root_block_device.3018388612.volume_size":           "10",
+				"root_block_device.3018388612.volume_type":           "io1",
+				"root_block_device.3018388612.iops":                  "1000",
+			},
+			Expected: map[string]string{
+				"ebs_block_device.#":                                 "1",
+				"ebs_block_device.3851383343.delete_on_termination":  "true",
+				"ebs_block_device.3851383343.device_name":            "/dev/sdx",
+				"ebs_block_device.3851383343.encrypted":              "false",
+				"ebs_block_device.3851383343.snapshot_id":            "",
+				"ebs_block_device.3851383343.volume_size":            "5",
+				"ebs_block_device.3851383343.volume_type":            "standard",
+				"ephemeral_block_device.#":                           "1",
+				"ephemeral_block_device.2458403513.device_name":      "/dev/sdy",
+				"ephemeral_block_device.2458403513.virtual_name":     "ephemeral0",
+				"root_block_device.#":                                "1",
+				"root_block_device.3018388612.delete_on_termination": "true",
+				"root_block_device.3018388612.device_name":           "/dev/sda1",
+				"root_block_device.3018388612.snapshot_id":           "",
+				"root_block_device.3018388612.volume_size":           "10",
+				"root_block_device.3018388612.volume_type":           "io1",
+				"root_block_device.3018388612.iops":                  "1000",
+			},
+		},
+	}
+
+	for tn, tc := range cases {
+		is := &terraform.InstanceState{
+			Attributes: tc.Attributes,
+		}
+		is, err := resourceAwsInstanceMigrateState(
+			tc.StateVersion, is, tc.Meta)
+
+		if err != nil {
+			t.Fatalf("bad: %s, err: %#v", tn, err)
+		}
+
+		for k, v := range tc.Expected {
+			if is.Attributes[k] != v {
+				t.Fatalf(
+					"bad: %s\n\n expected: %#v -> %#v\n got: %#v -> %#v\n in: %#v",
+					tn, k, v, k, is.Attributes[k], is.Attributes)
+			}
+		}
+	}
+}

builtin/providers/aws/resource_aws_instance_test.go

@@ -111,31 +111,33 @@ func TestAccAWSInstance_blockDevices(t *testing.T) {
 					resource.TestCheckResourceAttr(
 						"aws_instance.foo", "root_block_device.#", "1"),
 					resource.TestCheckResourceAttr(
-						"aws_instance.foo", "root_block_device.0.device_name", "/dev/sda1"),
+						"aws_instance.foo", "root_block_device.3018388612.device_name", "/dev/sda1"),
 					resource.TestCheckResourceAttr(
-						"aws_instance.foo", "root_block_device.0.volume_size", "11"),
+						"aws_instance.foo", "root_block_device.3018388612.volume_size", "11"),
-					// this one is important because it's the only root_block_device
-					// attribute that comes back from the API. so checking it verifies
-					// that we set state properly
 					resource.TestCheckResourceAttr(
-						"aws_instance.foo", "root_block_device.0.volume_type", "gp2"),
+						"aws_instance.foo", "root_block_device.3018388612.volume_type", "gp2"),
 					resource.TestCheckResourceAttr(
-						"aws_instance.foo", "block_device.#", "2"),
+						"aws_instance.foo", "ebs_block_device.#", "2"),
 					resource.TestCheckResourceAttr(
-						"aws_instance.foo", "block_device.172787947.device_name", "/dev/sdb"),
+						"aws_instance.foo", "ebs_block_device.418220885.device_name", "/dev/sdb"),
 					resource.TestCheckResourceAttr(
-						"aws_instance.foo", "block_device.172787947.volume_size", "9"),
+						"aws_instance.foo", "ebs_block_device.418220885.volume_size", "9"),
 					resource.TestCheckResourceAttr(
-						"aws_instance.foo", "block_device.172787947.iops", "0"),
+						"aws_instance.foo", "ebs_block_device.418220885.volume_type", "standard"),
-					// Check provisioned SSD device
 					resource.TestCheckResourceAttr(
-						"aws_instance.foo", "block_device.3336996981.volume_type", "io1"),
+						"aws_instance.foo", "ebs_block_device.1877654467.device_name", "/dev/sdc"),
 					resource.TestCheckResourceAttr(
-						"aws_instance.foo", "block_device.3336996981.device_name", "/dev/sdc"),
+						"aws_instance.foo", "ebs_block_device.1877654467.volume_size", "10"),
 					resource.TestCheckResourceAttr(
-						"aws_instance.foo", "block_device.3336996981.volume_size", "10"),
+						"aws_instance.foo", "ebs_block_device.1877654467.volume_type", "io1"),
 					resource.TestCheckResourceAttr(
-						"aws_instance.foo", "block_device.3336996981.iops", "100"),
+						"aws_instance.foo", "ebs_block_device.1877654467.iops", "100"),
+					resource.TestCheckResourceAttr(
+						"aws_instance.foo", "ephemeral_block_device.#", "1"),
+					resource.TestCheckResourceAttr(
+						"aws_instance.foo", "ephemeral_block_device.2087552357.device_name", "/dev/sde"),
+					resource.TestCheckResourceAttr(
+						"aws_instance.foo", "ephemeral_block_device.2087552357.virtual_name", "ephemeral0"),
 					testCheck(),
 				),
 			},
@@ -420,21 +422,26 @@ resource "aws_instance" "foo" {
 	# us-west-2
 	ami = "ami-55a7ea65"
 	instance_type = "m1.small"
+
 	root_block_device {
 		device_name = "/dev/sda1"
 		volume_type = "gp2"
 		volume_size = 11
 	}
-	block_device {
+	ebs_block_device {
 		device_name = "/dev/sdb"
 		volume_size = 9
 	}
-	block_device {
+	ebs_block_device {
 		device_name = "/dev/sdc"
 		volume_size = 10
 		volume_type = "io1"
 		iops = 100
 	}
+	ephemeral_block_device {
+		device_name = "/dev/sde"
+		virtual_name = "ephemeral0"
+	}
 }
 `
 

helper/schema/resource.go

@@ -151,7 +151,7 @@ func (r *Resource) Apply(
 		err = r.Update(data, meta)
 	}
 
-	return data.State(), err
+	return r.recordCurrentSchemaVersion(data.State()), err
 }
 
 // Diff returns a diff of this resource and is API compatible with the
@@ -207,14 +207,7 @@ func (r *Resource) Refresh(
 		state = nil
 	}
 
-	if state != nil && r.SchemaVersion > 0 {
+	return r.recordCurrentSchemaVersion(state), err
-		if state.Meta == nil {
-			state.Meta = make(map[string]string)
-		}
-		state.Meta["schema_version"] = strconv.Itoa(r.SchemaVersion)
-	}
-
-	return state, err
 }
 
 // InternalValidate should be called to validate the structure
@@ -241,3 +234,14 @@ func (r *Resource) checkSchemaVersion(is *terraform.InstanceState) (bool, int) {
 	stateSchemaVersion, _ := strconv.Atoi(is.Meta["schema_version"])
 	return stateSchemaVersion < r.SchemaVersion, stateSchemaVersion
 }
+
+func (r *Resource) recordCurrentSchemaVersion(
+	state *terraform.InstanceState) *terraform.InstanceState {
+	if state != nil && r.SchemaVersion > 0 {
+		if state.Meta == nil {
+			state.Meta = make(map[string]string)
+		}
+		state.Meta["schema_version"] = strconv.Itoa(r.SchemaVersion)
+	}
+	return state
+}

helper/schema/resource_test.go

@@ -11,6 +11,7 @@ import (
 
 func TestResourceApply_create(t *testing.T) {
 	r := &Resource{
+		SchemaVersion: 2,
 		Schema: map[string]*Schema{
 			"foo": &Schema{
 				Type:     TypeInt,
@@ -51,6 +52,9 @@ func TestResourceApply_create(t *testing.T) {
 			"id":  "foo",
 			"foo": "42",
 		},
+		Meta: map[string]string{
+			"schema_version": "2",
+		},
 	}
 
 	if !reflect.DeepEqual(actual, expected) {
@@ -339,6 +343,7 @@ func TestResourceInternalValidate(t *testing.T) {
 
 func TestResourceRefresh(t *testing.T) {
 	r := &Resource{
+		SchemaVersion: 2,
 		Schema: map[string]*Schema{
 			"foo": &Schema{
 				Type:     TypeInt,
@@ -368,6 +373,9 @@ func TestResourceRefresh(t *testing.T) {
 			"id":  "bar",
 			"foo": "13",
 		},
+		Meta: map[string]string{
+			"schema_version": "2",
+		},
 	}
 
 	actual, err := r.Refresh(s, 42)

terraform/state.go

@@ -843,6 +843,9 @@ func (i *InstanceState) init() {
 	if i.Attributes == nil {
 		i.Attributes = make(map[string]string)
 	}
+	if i.Meta == nil {
+		i.Meta = make(map[string]string)
+	}
 	i.Ephemeral.init()
 }
 
@@ -860,6 +863,12 @@ func (i *InstanceState) deepcopy() *InstanceState {
 			n.Attributes[k] = v
 		}
 	}
+	if i.Meta != nil {
+		n.Meta = make(map[string]string, len(i.Meta))
+		for k, v := range i.Meta {
+			n.Meta[k] = v
+		}
+	}
 	return n
 }
 

website/source/docs/providers/aws/r/instance.html.markdown

@@ -14,7 +14,8 @@ and deleted. Instances also support [provisioning](/docs/provisioners/index.html
 ## Example Usage
 
 ```
-# Create a new instance of the ami-1234 on an m1.small node with an AWS Tag naming it "HelloWorld"
+# Create a new instance of the ami-1234 on an m1.small node
+# with an AWS Tag naming it "HelloWorld"
 resource "aws_instance" "web" {
     ami = "ami-1234"
     instance_type = "m1.small"
@@ -47,32 +48,79 @@ The following arguments are supported:
 * `iam_instance_profile` - (Optional) The IAM Instance Profile to
   launch the instance with.
 * `tags` - (Optional) A mapping of tags to assign to the resource.
-* `block_device` - (Optional) A list of block devices to add. Their keys are documented below.
 * `root_block_device` - (Optional) Customize details about the root block
-  device of the instance. Available keys are documented below.
+  device of the instance. See [Block Devices](#block-devices) below for details.
+* `ebs_block_device` - (Optional) Additional EBS block devices to attach to the
+  instance.  See [Block Devices](#block-devices) below for details.
+* `ephemeral_block_device` - (Optional) Customize Ephemeral (also known as
+  "Instance Store") volumes on the instance. See [Block Devices](#block-devices) below for details.
 
-Each `block_device` supports the following:
 
-* `device_name` - The name of the device to mount.
+<a id="block-devices"></a>
-* `virtual_name` - (Optional) The virtual device name.
+## Block devices
-* `snapshot_id` - (Optional) The Snapshot ID to mount.
+
-* `volume_type` - (Optional) The type of volume. Can be standard, gp2, or io1. Defaults to standard.
+Each of the `*_block_device` attributes controls a portion of the AWS
-* `volume_size` - (Optional) The size of the volume in gigabytes.
+Instance's "Block Device Mapping". It's a good idea to familiarize yourself with [AWS's Block Device
-* `iops` - (Optional) The amount of provisioned IOPS. Setting this implies a
+Mapping docs](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/block-device-mapping-concepts.html)
-    volume_type of "io1".
+to understand the implications of using these attributes.
-* `delete_on_termination` - (Optional) Should the volume be destroyed on instance termination (defaults true).
-* `encrypted` - (Optional) Should encryption be enabled (defaults false).
 
 The `root_block_device` mapping supports the following:
 
 * `device_name` - The name of the root device on the target instance. Must
-  match the root device as defined in the AMI. Defaults to "/dev/sda1", which
+  match the root device as defined in the AMI. Defaults to `"/dev/sda1"`, which
   is the typical root volume for Linux instances.
-* `volume_type` - (Optional) The type of volume. Can be standard, gp2, or io1. Defaults to standard.
+* `volume_type` - (Optional) The type of volume. Can be `"standard"`, `"gp2"`,
+  or `"io1"`. (Default: `"standard"`).
 * `volume_size` - (Optional) The size of the volume in gigabytes.
-* `iops` - (Optional) The amount of provisioned IOPS. Setting this implies a
+* `iops` - (Optional) The amount of provisioned
-    volume_type of "io1".
+  [IOPS](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ebs-io-characteristics.html).
-* `delete_on_termination` - (Optional) Should the volume be destroyed on instance termination (defaults true).
+  This must be set with a `volume_type` of `"io1"`.
+* `delete_on_termination` - (Optional) Whether the volume should be destroyed
+  on instance termination (Default: `true`).
+
+Modifying any of the `root_block_device` settings requires resource
+replacement.
+
+Each `ebs_block_device` supports the following:
+
+* `device_name` - The name of the device to mount.
+* `snapshot_id` - (Optional) The Snapshot ID to mount.
+* `volume_type` - (Optional) The type of volume. Can be `"standard"`, `"gp2"`,
+  or `"io1"`. (Default: `"standard"`).
+* `volume_size` - (Optional) The size of the volume in gigabytes.
+* `iops` - (Optional) The amount of provisioned
+  [IOPS](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ebs-io-characteristics.html).
+  This must be set with a `volume_type` of `"io1"`.
+* `delete_on_termination` - (Optional) Whether the volume should be destroyed
+  on instance termination (Default: `true`).
+* `encrypted` - (Optional) Enables [EBS
+  encryption](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/EBSEncryption.html)
+  on the volume (Default: `false`).
+
+Modifying any `ebs_block_device` currently requires resource replacement.
+
+Each `ephemeral_block_device` supports the following:
+
+* `device_name` - The name of the block device to mount on the instance.
+* `virtual_name` - The [Instance Store Device
+  Name](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/InstanceStorage.html#InstanceStoreDeviceNames)
+  (e.g. `"ephemeral0"`)
+
+Each AWS Instance type has a different set of Instance Store block devices
+available for attachment. AWS [publishes a
+list](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/InstanceStorage.html#StorageOnInstanceTypes)
+of which ephemeral devices are available on each type. The devices are always
+identified by the `virtual_name` in the format `"ephemeral{0..N}"`.
+
+
+~> **NOTE:** Because AWS [does not expose Instance Store mapping
+details](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/block-device-mapping-concepts.html#bdm-instance-metadata)
+via an externally accessible API, `ephemeral_block_device` configuration may
+only be applied at instance creation time, and changes to configuration of
+existing resources cannot be detected by Terraform. Updates to Instance Store
+block device configuration can be manually triggered by using the [`taint`
+command](/docs/commands/taint.html).
+
 
 ## Attributes Reference