Implements Snapshot tagging

While implementing my acceptance test, I stumbled upon a comment stating
that snapshot deletion should also be implemented, so I snuck that in. I
can't help but wonder if there is some generic logic that is implemented
a few times throughout the packer code base that could maybe better serve
us if it were abstracted to the common package.

builder/amazon/common/artifact.go

@@ -79,6 +79,19 @@ func (a *Artifact) Destroy() error {
 		}
 		regionConn := ec2.New(session)
 
+		// Get image metadata
+		imageResp, err := regionConn.DescribeImages(&ec2.DescribeImagesInput{
+			ImageIds: []*string{&imageId},
+		})
+		if err != nil {
+			errors = append(errors, err)
+		}
+		if len(imageResp.Images) == 0 {
+			err := fmt.Errorf("Error retrieving details for AMI (%s), no images found", imageId)
+			errors = append(errors, err)
+		}
+
+		// Deregister ami
 		input := &ec2.DeregisterImageInput{
 			ImageId: &imageId,
 		}

builder/amazon/common/step_create_tags.go

@@ -22,12 +22,17 @@ func (s *StepCreateTags) Run(state multistep.StateBag) multistep.StepAction {
 	ui := state.Get("ui").(packer.Ui)
 	amis := state.Get("amis").(map[string]string)
 
-	if len(s.Tags) > 0 || len(s.SnapshotTags) > 0 {
+	if len(s.Tags) == 0 && len(s.SnapshotTags) == 0 {
+		return multistep.ActionContinue
+	}
+
+	// Adds tags to AMIs and snapshots
 	for region, ami := range amis {
 		ui.Say(fmt.Sprintf("Adding tags to AMI (%s)...", ami))
 
 		// Convert tags to ec2.Tag format
-			ec2Tags := ConvertToEC2Tags(s.Tags, ui)
+		amiTags := ConvertToEC2Tags(s.Tags, ui)
+		ui.Say(fmt.Sprintf("Snapshot tags:"))
 		snapshotTags := ConvertToEC2Tags(s.SnapshotTags, ui)
 
 		// Declare list of resources to tag
@@ -81,11 +86,8 @@ func (s *StepCreateTags) Run(state multistep.StateBag) multistep.StepAction {
 			// Tag images and snapshots
 			_, err := regionconn.CreateTags(&ec2.CreateTagsInput{
 				Resources: resourceIds,
-					Tags:      ec2Tags,
+				Tags:      amiTags,
 			})
-				if err == nil {
-					return true, nil
-				}
 			if awsErr, ok := err.(awserr.Error); ok {
 				if awsErr.Code() == "InvalidAMIID.NotFound" ||
 					awsErr.Code() == "InvalidSnapshot.NotFound" {
@@ -116,7 +118,6 @@ func (s *StepCreateTags) Run(state multistep.StateBag) multistep.StepAction {
 			return multistep.ActionHalt
 		}
 	}
-	}
 
 	return multistep.ActionContinue
 }
@@ -126,13 +127,13 @@ func (s *StepCreateTags) Cleanup(state multistep.StateBag) {
 }
 
 func ConvertToEC2Tags(tags map[string]string, ui packer.Ui) []*ec2.Tag {
-	var ec2Tags []*ec2.Tag
+	var amiTags []*ec2.Tag
 	for key, value := range tags {
 		ui.Message(fmt.Sprintf("Adding tag: \"%s\": \"%s\"", key, value))
-		ec2Tags = append(ec2Tags, &ec2.Tag{
+		amiTags = append(amiTags, &ec2.Tag{
 			Key:   aws.String(key),
 			Value: aws.String(value),
 		})
 	}
-	return ec2Tags
+	return amiTags
 }

builder/amazon/ebs/tags_acc_test.go

@@ -1,6 +1,7 @@
 package ebs
 
 import (
+	"encoding/json"
 	"fmt"
 	"testing"
 
@@ -11,6 +12,21 @@ import (
 	"github.com/mitchellh/packer/packer"
 )
 
+type TFBuilder struct {
+	Type         string            `json:"type"`
+	Region       string            `json:"region"`
+	SourceAmi    string            `json:"source_ami"`
+	InstanceType string            `json:"instance_type"`
+	SshUsername  string            `json:"ssh_username"`
+	AmiName      string            `json:"ami_name"`
+	Tags         map[string]string `json:"tags"`
+	SnapshotTags map[string]string `json:"snapshot_tags"`
+}
+
+type TFConfig struct {
+	Builders []TFBuilder `json:"builders"`
+}
+
 func TestBuilderTagsAcc_basic(t *testing.T) {
 	builderT.Test(t, builderT.TestCase{
 		PreCheck: func() { testAccPreCheck(t) },
@@ -26,9 +42,10 @@ func checkTags() builderT.TestCheckFunc {
 			return fmt.Errorf("more than 1 artifact")
 		}
 
-		tags := make(map[string]string)
+		config := TFConfig{}
-		tags["OS_Version"] = "Ubuntu"
+		json.Unmarshal([]byte(testBuilderTagsAccBasic), &config)
-		tags["Release"] = "Latest"
+		tags := config.Builders[0].Tags
+		snapshotTags := config.Builders[0].SnapshotTags
 
 		// Get the actual *Artifact pointer so we can access the AMIs directly
 		artifactRaw := artifacts[0]
@@ -37,18 +54,18 @@ func checkTags() builderT.TestCheckFunc {
 			return fmt.Errorf("unknown artifact: %#v", artifactRaw)
 		}
 
-		// describe the image, get block devices with a snapshot
+		// Describe the image, get block devices with a snapshot
 		ec2conn, _ := testEC2Conn()
 		imageResp, err := ec2conn.DescribeImages(&ec2.DescribeImagesInput{
 			ImageIds: []*string{aws.String(artifact.Amis["us-east-1"])},
 		})
 
 		if err != nil {
-			return fmt.Errorf("Error retrieving details for AMI Artifcat (%#v) in Tags Test: %s", artifact, err)
+			return fmt.Errorf("Error retrieving details for AMI Artifact (%#v) in Tags Test: %s", artifact, err)
 		}
 
 		if len(imageResp.Images) == 0 {
-			return fmt.Errorf("No images found for AMI Artifcat (%#v) in Tags Test: %s", artifact, err)
+			return fmt.Errorf("No images found for AMI Artifact (%#v) in Tags Test: %s", artifact, err)
 		}
 
 		image := imageResp.Images[0]
@@ -61,7 +78,7 @@ func checkTags() builderT.TestCheckFunc {
 			}
 		}
 
-		// grab matching snapshot info
+		// Grab matching snapshot info
 		resp, err := ec2conn.DescribeSnapshots(&ec2.DescribeSnapshotsInput{
 			SnapshotIds: snapshots,
 		})
@@ -74,12 +91,14 @@ func checkTags() builderT.TestCheckFunc {
 			return fmt.Errorf("No Snapshots found for AMI Artifcat (%#v) in Tags Test", artifact)
 		}
 
-		// grab the snapshots, check the tags
+		// Grab the snapshots, check the tags
 		for _, s := range resp.Snapshots {
 			expected := len(tags)
 			for _, t := range s.Tags {
 				for key, value := range tags {
-					if key == *t.Key && value == *t.Value {
+					if val, ok := snapshotTags[key]; ok && val == *t.Value {
+						expected--
+					} else if key == *t.Key && value == *t.Value {
 						expected--
 					}
 				}
@@ -106,7 +125,11 @@ const testBuilderTagsAccBasic = `
       "ami_name": "packer-tags-testing-{{timestamp}}",
       "tags": {
         "OS_Version": "Ubuntu",
-        "Release": "Latest"
+        "Release": "Latest",
+        "Name": "Bleep"
+      },
+      "snapshot_tags": {
+        "Name": "Foobar"
       }
     }
   ]