Add a subbindings resource as /pods/{name}/binding

Allows POST to create a binding as a child. Also refactors internal
and v1beta3 Binding to be more generic (so that other resources can
support Bindings).

pkg/api/testing/fuzzer.go

@@ -101,6 +101,10 @@ func FuzzerFor(t *testing.T, version string, src rand.Source) *fuzz.Fuzzer {
 			j.Spec = api.PodSpec{}
 			c.Fuzz(&j.Spec)
 		},
+		func(j *api.Binding, c fuzz.Continue) {
+			c.Fuzz(&j.ObjectMeta)
+			j.Target.Name = c.RandString()
+		},
 		func(j *api.ReplicationControllerSpec, c fuzz.Continue) {
 			c.FuzzNoCustom(j)   // fuzz self without calling this function again
 			j.TemplateRef = nil // this is required for round trip

pkg/api/types.go

@@ -918,13 +918,14 @@ type NamespaceList struct {
 	Items []Namespace `json:"items"`
 }
 
-// Binding is written by a scheduler to cause a pod to be bound to a host.
+// Binding ties one object to another - for example, a pod is bound to a node by a scheduler.
 type Binding struct {
-	TypeMeta   `json:",inline"`
+	TypeMeta `json:",inline"`
+	// ObjectMeta describes the object that is being bound.
 	ObjectMeta `json:"metadata,omitempty"`
 
-	PodID string `json:"podID"`
-	Host  string `json:"host"`
+	// Target is the object to bind to.
+	Target ObjectReference `json:"target"`
 }
 
 // Status is a return value for calls that don't return other objects.

pkg/api/v1beta1/conversion.go

@@ -1324,6 +1324,24 @@ func init() {
 
 			return nil
 		},
+		func(in *Binding, out *newer.Binding, s conversion.Scope) error {
+			if err := s.DefaultConvert(in, out, conversion.IgnoreMissingFields); err != nil {
+				return err
+			}
+			out.Target = newer.ObjectReference{
+				Name: in.Host,
+			}
+			out.Name = in.PodID
+			return nil
+		},
+		func(in *newer.Binding, out *Binding, s conversion.Scope) error {
+			if err := s.DefaultConvert(in, out, conversion.IgnoreMissingFields); err != nil {
+				return err
+			}
+			out.Host = in.Target.Name
+			out.PodID = in.Name
+			return nil
+		},
 	)
 	if err != nil {
 		// If one of the conversion functions is malformed, detect it immediately.

pkg/api/v1beta2/conversion.go

@@ -1240,6 +1240,24 @@ func init() {
 
 			return nil
 		},
+		func(in *Binding, out *newer.Binding, s conversion.Scope) error {
+			if err := s.DefaultConvert(in, out, conversion.IgnoreMissingFields); err != nil {
+				return err
+			}
+			out.Target = newer.ObjectReference{
+				Name: in.Host,
+			}
+			out.Name = in.PodID
+			return nil
+		},
+		func(in *newer.Binding, out *Binding, s conversion.Scope) error {
+			if err := s.DefaultConvert(in, out, conversion.IgnoreMissingFields); err != nil {
+				return err
+			}
+			out.Host = in.Target.Name
+			out.PodID = in.Name
+			return nil
+		},
 	)
 	if err != nil {
 		// If one of the conversion functions is malformed, detect it immediately.

pkg/api/v1beta3/types.go

@@ -940,16 +940,14 @@ type NamespaceList struct {
 	Items []Namespace `json:"items"  description:"items is the list of Namespace objects in the list"`
 }
 
-// Binding is written by a scheduler to cause a pod to be bound to a node. Name is not
-// required for Bindings.
+// Binding ties one object to another - for example, a pod is bound to a node by a scheduler.
 type Binding struct {
-	TypeMeta   `json:",inline"`
+	TypeMeta `json:",inline"`
+	// ObjectMeta describes the object that is being bound.
 	ObjectMeta `json:"metadata,omitempty" description:"standard object metadata; see https://github.com/GoogleCloudPlatform/kubernetes/blob/master/docs/api-conventions.md#metadata"`
 
-	// PodID is a Pod name to be bound to a node.
-	PodID string `json:"podID" description:"name of the pod to be bound to a node"`
-	// Host is the name of a node to bind to.
-	Host string `json:"host" description:"name of the node to bind to"`
+	// Target is the object to bind to.
+	Target ObjectReference `json:"target" description:"an object to bind to"`
 }
 
 // Status is a return value for calls that don't return other objects.