builder/digitalocean: add a droplet_name configuration value

Practically, this lets you set the hostname of the droplet
used for provisioning.

builder/digitalocean/builder.go

@@ -8,6 +8,7 @@ import (
 	"fmt"
 	"github.com/mitchellh/multistep"
 	"github.com/mitchellh/packer/common"
+	"github.com/mitchellh/packer/common/uuid"
 	"github.com/mitchellh/packer/packer"
 	"log"
 	"os"
@@ -30,6 +31,7 @@ type config struct {
 	ImageID  uint   `mapstructure:"image_id"`
 
 	SnapshotName string `mapstructure:"snapshot_name"`
+	DropletName  string `mapstructure:"droplet_name"`
 	SSHUsername  string `mapstructure:"ssh_username"`
 	SSHPort      uint   `mapstructure:"ssh_port"`
 
@@ -95,6 +97,11 @@ func (b *Builder) Prepare(raws ...interface{}) ([]string, error) {
 		b.config.SnapshotName = "packer-{{timestamp}}"
 	}
 
+	if b.config.DropletName == "" {
+		// Default to packer-[time-ordered-uuid]
+		b.config.DropletName = fmt.Sprintf("packer-%s", uuid.TimeOrderedUUID())
+	}
+
 	if b.config.SSHUsername == "" {
 		// Default to "root". You can override this if your
 		// SourceImage has a different user account then the DO default
@@ -121,6 +128,7 @@ func (b *Builder) Prepare(raws ...interface{}) ([]string, error) {
 		"client_id":     &b.config.ClientID,
 		"api_key":       &b.config.APIKey,
 		"snapshot_name": &b.config.SnapshotName,
+		"droplet_name":  &b.config.DropletName,
 		"ssh_username":  &b.config.SSHUsername,
 		"ssh_timeout":   &b.config.RawSSHTimeout,
 		"state_timeout": &b.config.RawStateTimeout,

builder/digitalocean/builder_test.go

@@ -401,3 +401,55 @@ func TestBuilderPrepare_SnapshotName(t *testing.T) {
 	}
 
 }
+
+func TestBuilderPrepare_DropletName(t *testing.T) {
+	var b Builder
+	config := testConfig()
+
+	// Test default
+	warnings, err := b.Prepare(config)
+	if len(warnings) > 0 {
+		t.Fatalf("bad: %#v", warnings)
+	}
+	if err != nil {
+		t.Fatalf("should not have error: %s", err)
+	}
+
+	if b.config.DropletName == "" {
+		t.Errorf("invalid: %s", b.config.DropletName)
+	}
+
+	// Test normal set
+	config["droplet_name"] = "foobar"
+	b = Builder{}
+	warnings, err = b.Prepare(config)
+	if len(warnings) > 0 {
+		t.Fatalf("bad: %#v", warnings)
+	}
+	if err != nil {
+		t.Fatalf("should not have error: %s", err)
+	}
+
+	// Test with template
+	config["droplet_name"] = "foobar-{{timestamp}}"
+	b = Builder{}
+	warnings, err = b.Prepare(config)
+	if len(warnings) > 0 {
+		t.Fatalf("bad: %#v", warnings)
+	}
+	if err != nil {
+		t.Fatalf("should not have error: %s", err)
+	}
+
+	// Test with bad template
+	config["droplet_name"] = "foobar-{{"
+	b = Builder{}
+	warnings, err = b.Prepare(config)
+	if len(warnings) > 0 {
+		t.Fatalf("bad: %#v", warnings)
+	}
+	if err == nil {
+		t.Fatal("should have error")
+	}
+
+}

builder/digitalocean/step_create_droplet.go

@@ -3,7 +3,6 @@ package digitalocean
 import (
 	"fmt"
 	"github.com/mitchellh/multistep"
-	"github.com/mitchellh/packer/common/uuid"
 	"github.com/mitchellh/packer/packer"
 )
 
@@ -19,11 +18,9 @@ func (s *stepCreateDroplet) Run(state multistep.StateBag) multistep.StepAction {
 
 	ui.Say("Creating droplet...")
 
-	// Some random droplet name as it's temporary
-	name := fmt.Sprintf("packer-%s", uuid.TimeOrderedUUID())
-
 	// Create the droplet based on configuration
-	dropletId, err := client.CreateDroplet(name, c.SizeID, c.ImageID, c.RegionID, sshKeyId)
+	dropletId, err := client.CreateDroplet(c.DropletName, c.SizeID, c.ImageID, c.RegionID, sshKeyId)
+
 	if err != nil {
 		err := fmt.Errorf("Error creating droplet: %s", err)
 		state.Put("error", err)

website/source/docs/builders/digitalocean.html.markdown

@@ -51,6 +51,9 @@ Optional:
   To help make this unique, use a function like `timestamp` (see
   [configuration templates](/docs/templates/configuration-templates.html) for more info)
 
+* `droplet_name` (string) - The name assigned to the droplet. DigitalOcean
+  sets the hostname of the machine to this value.
+
 * `ssh_port` (int) - The port that SSH will be available on. Defaults to port
   22.