packer: Add Destroy method to artifact

[GH-18]

builder/amazonebs/artifact.go

 package amazonebs
 
 import (
+	"errors"
 	"fmt"
 	"strings"
 )
@@ -33,3 +34,7 @@ func (a *artifact) String() string {
 
 	return fmt.Sprintf("AMIs were created:\n\n%s", strings.Join(amiStrings, "\n"))
 }
+
+func (a *artifact) Destroy() error {
+	return errors.New("not implemented yet")
+}

builder/digitalocean/artifact.go

 package digitalocean
 
 import (
+	"errors"
 	"fmt"
 )
 
@@ -25,3 +26,7 @@ func (a *Artifact) Id() string {
 func (a *Artifact) String() string {
 	return fmt.Sprintf("A snapshot was created: %v", a.snapshotName)
 }
+
+func (a *Artifact) Destroy() error {
+	return errors.New("not implemented yet")
+}

builder/vmware/artifact.go

 package vmware
 
-import "fmt"
+import (
+	"fmt"
+	"os"
+)
 
 // Artifact is the result of running the VMware builder, namely a set
 // of files associated with the resulting machine.
@@ -24,3 +27,7 @@ func (*Artifact) Id() string {
 func (a *Artifact) String() string {
 	return fmt.Sprintf("VM files in directory: %s", a.dir)
 }
+
+func (a *Artifact) Destroy() error {
+	return os.RemoveAll(a.dir)
+}

packer/artifact.go

@@ -24,4 +24,9 @@ type Artifact interface {
 	// Returns human-readable output that describes the artifact created.
 	// This is used for UI output. It can be multiple lines.
 	String() string
+
+	// Destroy deletes the artifact. Packer calls this for various reasons,
+	// such as if a post-processor has processed this artifact and it is
+	// no longer needed.
+	Destroy() error
 }

packer/artifact_test.go

@@ -17,3 +17,7 @@ func (*TestArtifact) Id() string {
 func (*TestArtifact) String() string {
 	return "string"
 }
+
+func (*TestArtifact) Destroy() error {
+	return nil
+}

packer/rpc/artifact.go

@@ -41,6 +41,15 @@ func (a *artifact) String() (result string) {
 	return
 }
 
+func (a *artifact) Destroy() error {
+	var result error
+	if err := a.client.Call("Artifact.Destroy", new(interface{}), &result); err != nil {
+		return err
+	}
+
+	return result
+}
+
 func (s *ArtifactServer) BuilderId(args *interface{}, reply *string) error {
 	*reply = s.artifact.BuilderId()
 	return nil
@@ -60,3 +69,13 @@ func (s *ArtifactServer) String(args *interface{}, reply *string) error {
 	*reply = s.artifact.String()
 	return nil
 }
+
+func (s *ArtifactServer) Destroy(args *interface{}, reply *error) error {
+	err := s.artifact.Destroy()
+	if err != nil {
+		err = NewBasicError(err)
+	}
+
+	*reply = err
+	return nil
+}

packer/rpc/artifact_test.go

@@ -25,6 +25,10 @@ func (testArtifact) String() string {
 	return "string"
 }
 
+func (testArtifact) Destroy() error {
+	return nil
+}
+
 func TestArtifactRPC(t *testing.T) {
 	assert := asserts.NewTestingAsserts(t, true)