builder/amazon/chroot: step to gather instance info

builder/amazon/chroot/builder.go

@@ -72,7 +72,7 @@ func (b *Builder) Run(ui packer.Ui, hook packer.Hook, cache packer.Cache) (packe
 
 	// Build the steps
 	steps := []multistep.Step{
-		&StepCheckEC2{},
+		&StepInstanceInfo{},
 		&StepSourceAMIInfo{},
 		&StepCreateVolume{},
 	}

builder/amazon/chroot/step_check_ec2.go

@@ -1,33 +0,0 @@
-package chroot
-
-import (
-	"fmt"
-	"github.com/mitchellh/goamz/aws"
-	"github.com/mitchellh/multistep"
-	"github.com/mitchellh/packer/packer"
-	"log"
-)
-
-// StepCheckEC2 verifies that this builder is running on an EC2 instance.
-type StepCheckEC2 struct{}
-
-func (s *StepCheckEC2) Run(state map[string]interface{}) multistep.StepAction {
-	ui := state["ui"].(packer.Ui)
-
-	ui.Say("Verifying we're on an EC2 instance...")
-	id, err := aws.GetMetaData("instance-id")
-	if err != nil {
-		log.Printf("Error: %s", err)
-		err := fmt.Errorf(
-			"Error retrieving the ID of the instance Packer is running on.\n" +
-				"Please verify Packer is running on a proper AWS EC2 instance.")
-		state["error"] = err
-		ui.Error(err.Error())
-		return multistep.ActionHalt
-	}
-	log.Printf("Instance ID: %s", string(id))
-
-	return multistep.ActionContinue
-}
-
-func (s *StepCheckEC2) Cleanup(map[string]interface{}) {}

builder/amazon/chroot/step_instance_info.go

@@ -0,0 +1,57 @@
+package chroot
+
+import (
+	"fmt"
+	"github.com/mitchellh/goamz/aws"
+	"github.com/mitchellh/goamz/ec2"
+	"github.com/mitchellh/multistep"
+	"github.com/mitchellh/packer/packer"
+	"log"
+)
+
+// StepInstanceInfo verifies that this builder is running on an EC2 instance.
+type StepInstanceInfo struct{}
+
+func (s *StepInstanceInfo) Run(state map[string]interface{}) multistep.StepAction {
+	ec2conn := state["ec2"].(*ec2.EC2)
+	ui := state["ui"].(packer.Ui)
+
+	// Get our own instance ID
+	ui.Say("Gathering information about this EC2 instance...")
+	instanceIdBytes, err := aws.GetMetaData("instance-id")
+	if err != nil {
+		log.Printf("Error: %s", err)
+		err := fmt.Errorf(
+			"Error retrieving the ID of the instance Packer is running on.\n" +
+				"Please verify Packer is running on a proper AWS EC2 instance.")
+		state["error"] = err
+		ui.Error(err.Error())
+		return multistep.ActionHalt
+	}
+
+	instanceId := string(instanceIdBytes)
+	log.Printf("Instance ID: %s", instanceId)
+
+	// Query the entire instance metadata
+	instancesResp, err := ec2conn.Instances([]string{instanceId}, ec2.NewFilter())
+	if err != nil {
+		err := fmt.Errorf("Error getting instance data: %s", err)
+		state["error"] = err
+		ui.Error(err.Error())
+		return multistep.ActionHalt
+	}
+
+	if len(instancesResp.Reservations) == 0 {
+		err := fmt.Errorf("Error getting instance data: no instance found.")
+		state["error"] = err
+		ui.Error(err.Error())
+		return multistep.ActionHalt
+	}
+
+	instance := instancesResp.Reservations[0].Instances[0]
+	state["instance"] = instance
+
+	return multistep.ActionContinue
+}
+
+func (s *StepInstanceInfo) Cleanup(map[string]interface{}) {}