Expand Artifact API to expose build state

In order that something consuming an artifact can have access to extra
builder specific data add the State method which allows the caller to
ask for arbitary values by name.

builder/amazon/common/artifact.go

@@ -52,6 +52,10 @@ func (a *Artifact) String() string {
 	return fmt.Sprintf("AMIs were created:\n\n%s", strings.Join(amiStrings, "\n"))
 }
 
+func (a *Artifact) State(name string) interface{} {
+	return nil
+}
+
 func (a *Artifact) Destroy() error {
 	errors := make([]error, 0)
 

builder/digitalocean/artifact.go

@@ -37,6 +37,10 @@ func (a *Artifact) String() string {
 	return fmt.Sprintf("A snapshot was created: '%v' in region '%v'", a.snapshotName, a.regionName)
 }
 
+func (a *Artifact) State(name string) interface{} {
+	return nil
+}
+
 func (a *Artifact) Destroy() error {
 	log.Printf("Destroying image: %d (%s)", a.snapshotId, a.snapshotName)
 	return a.client.DestroyImage(a.snapshotId)

builder/docker/artifact_export.go

@@ -27,6 +27,10 @@ func (a *ExportArtifact) String() string {
 	return fmt.Sprintf("Exported Docker file: %s", a.path)
 }
 
+func (a *ExportArtifact) State(name string) interface{} {
+	return nil
+}
+
 func (a *ExportArtifact) Destroy() error {
 	return os.Remove(a.path)
 }

builder/docker/artifact_import.go

@@ -28,6 +28,10 @@ func (a *ImportArtifact) String() string {
 	return fmt.Sprintf("Imported Docker image: %s", a.Id())
 }
 
+func (*ImportArtifact) State(name string) interface{} {
+	return nil
+}
+
 func (a *ImportArtifact) Destroy() error {
 	return a.Driver.DeleteImage(a.Id())
 }

builder/googlecompute/artifact.go

@@ -37,3 +37,7 @@ func (a *Artifact) Id() string {
 func (a *Artifact) String() string {
 	return fmt.Sprintf("A disk image was created: %v", a.imageName)
 }
+
+func (a *Artifact) State(name string) interface{} {
+	return nil
+}

builder/null/artifact_export.go

@@ -24,6 +24,10 @@ func (a *NullArtifact) String() string {
 	return fmt.Sprintf("Did not export anything. This is the null builder")
 }
 
+func (a *NullArtifact) State(name string) interface{} {
+	return nil
+}
+
 func (a *NullArtifact) Destroy() error {
 	return nil
 }

builder/openstack/artifact.go

@@ -35,6 +35,10 @@ func (a *Artifact) String() string {
 	return fmt.Sprintf("An image was created: %v", a.ImageId)
 }
 
+func (a *Artifact) State(name string) interface{} {
+	return nil
+}
+
 func (a *Artifact) Destroy() error {
 	log.Printf("Destroying image: %d", a.ImageId)
 	return a.Conn.DeleteImageById(a.ImageId)

builder/parallels/common/artifact.go

@@ -66,6 +66,10 @@ func (a *artifact) String() string {
 	return fmt.Sprintf("VM files in directory: %s", a.dir)
 }
 
+func (a *artifact) State(name string) interface{} {
+	return nil
+}
+
 func (a *artifact) Destroy() error {
 	return os.RemoveAll(a.dir)
 }

builder/qemu/artifact.go

@@ -28,6 +28,10 @@ func (a *Artifact) String() string {
 	return fmt.Sprintf("VM files in directory: %s", a.dir)
 }
 
+func (a *Artifact) State(name string) interface{} {
+	return nil
+}
+
 func (a *Artifact) Destroy() error {
 	return os.RemoveAll(a.dir)
 }

builder/virtualbox/common/artifact.go

@@ -56,6 +56,10 @@ func (a *artifact) String() string {
 	return fmt.Sprintf("VM files in directory: %s", a.dir)
 }
 
+func (a *artifact) State(name string) interface{} {
+	return nil
+}
+
 func (a *artifact) Destroy() error {
 	return os.RemoveAll(a.dir)
 }

builder/vmware/common/artifact.go

@@ -56,6 +56,10 @@ func (a *localArtifact) String() string {
 	return fmt.Sprintf("VM files in directory: %s", a.dir)
 }
 
+func (a *localArtifact) State(name string) interface{} {
+	return nil
+}
+
 func (a *localArtifact) Destroy() error {
 	return os.RemoveAll(a.dir)
 }

builder/vmware/iso/artifact.go

@@ -28,6 +28,10 @@ func (a *Artifact) String() string {
 	return fmt.Sprintf("VM files in directory: %s", a.dir)
 }
 
+func (a *Artifact) State(name string) interface{} {
+	return nil
+}
+
 func (a *Artifact) Destroy() error {
 	return a.dir.RemoveAll()
 }

packer/artifact.go

@@ -25,6 +25,10 @@ type Artifact interface {
 	// This is used for UI output. It can be multiple lines.
 	String() string
 
+	// State allows the caller to ask for builder specific state information
+	// relating to the artifact instance.
+	State(name string) interface{}
+
 	// 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.

packer/artifact_mock.go

@@ -5,6 +5,7 @@ type MockArtifact struct {
 	BuilderIdValue string
 	FilesValue     []string
 	IdValue        string
+	StateValues    map[string]interface{}
 	DestroyCalled  bool
 }
 
@@ -37,6 +38,11 @@ func (*MockArtifact) String() string {
 	return "string"
 }
 
+func (a *MockArtifact) State(name string) interface{} {
+	value, _ := a.StateValues[name]
+	return value
+}
+
 func (a *MockArtifact) Destroy() error {
 	a.DestroyCalled = true
 	return nil

packer/artifact_test.go

@@ -2,6 +2,7 @@ package packer
 
 type TestArtifact struct {
 	id            string
+	state         map[string]interface{}
 	destroyCalled bool
 }
 
@@ -26,6 +27,11 @@ func (*TestArtifact) String() string {
 	return "string"
 }
 
+func (a *TestArtifact) State(name string) interface{} {
+	value, _ := a.state[name]
+	return value
+}
+
 func (a *TestArtifact) Destroy() error {
 	a.destroyCalled = true
 	return nil

packer/rpc/artifact.go

@@ -38,6 +38,11 @@ func (a *artifact) String() (result string) {
 	return
 }
 
+func (a *artifact) State(name string) (result interface{}) {
+	a.client.Call(a.endpoint+".State", name, &result)
+	return
+}
+
 func (a *artifact) Destroy() error {
 	var result error
 	if err := a.client.Call(a.endpoint+".Destroy", new(interface{}), &result); err != nil {
@@ -67,6 +72,11 @@ func (s *ArtifactServer) String(args *interface{}, reply *string) error {
 	return nil
 }
 
+func (s *ArtifactServer) State(name string, reply *interface{}) error {
+	*reply = s.artifact.State(name)
+	return nil
+}
+
 func (s *ArtifactServer) Destroy(args *interface{}, reply *error) error {
 	err := s.artifact.Destroy()
 	if err != nil {

post-processor/compress/artifact.go

@@ -35,6 +35,10 @@ func (self *Artifact) String() string {
 	return fmt.Sprintf("'%s' compressing: %s", self.Provider, self.Path)
 }
 
+func (*Artifact) State(name string) interface{} {
+	return nil
+}
+
 func (self *Artifact) Destroy() error {
 	return os.Remove(self.Path)
 }

post-processor/vagrant-cloud/artifact.go

@@ -34,6 +34,10 @@ func (a *Artifact) String() string {
 	return fmt.Sprintf("'%s': %s", a.Provider, a.Tag)
 }
 
+func (*Artifact) State(name string) interface{} {
+	return nil
+}
+
 func (a *Artifact) Destroy() error {
 	return nil
 }

post-processor/vagrant/artifact.go

@@ -35,6 +35,10 @@ func (a *Artifact) String() string {
 	return fmt.Sprintf("'%s' provider box: %s", a.Provider, a.Path)
 }
 
+func (a *Artifact) State(name string) interface{} {
+	return nil
+}
+
 func (a *Artifact) Destroy() error {
 	return os.Remove(a.Path)
 }