Don't delete 'headless' services

Deleting the clusterIP field when the service should be headless will
cause it to be assigned a new IP on restore; instead it should retain
the headless state after restoration.

Fixes #168

Signed-off-by: Nolan Brubaker <nolan@heptio.com>
(cherry picked from commit d87e8ee16e)

pkg/restore/restorers/service_restorer.go

@@ -45,7 +45,10 @@ func (sr *serviceRestorer) Prepare(obj runtime.Unstructured, restore *api.Restor
 		return nil, nil, err
 	}
 
-	delete(spec, "clusterIP")
+	// Since clusterIP is an optional key, we can ignore 'not found' errors. Also assuming it was a string already.
+	if val, _ := collections.GetString(spec, "clusterIP"); val != "None" {
+		delete(spec, "clusterIP")
+	}
 
 	ports, err := collections.GetSlice(obj.UnstructuredContent(), "spec.ports")
 	if err != nil {

pkg/restore/restorers/service_restorer_test.go

@@ -42,6 +42,12 @@ func TestServiceRestorerPrepare(t *testing.T) {
 			expectedErr: false,
 			expectedRes: NewTestUnstructured().WithName("svc-1").WithSpec("foo").WithSpecField("ports", []interface{}{}).Unstructured,
 		},
+		{
+			name:        "headless clusterIP should not be deleted from spec",
+			obj:         NewTestUnstructured().WithName("svc-1").WithSpecField("clusterIP", "None").WithSpecField("ports", []interface{}{}).Unstructured,
+			expectedErr: false,
+			expectedRes: NewTestUnstructured().WithName("svc-1").WithSpecField("clusterIP", "None").WithSpecField("ports", []interface{}{}).Unstructured,
+		},
 		{
 			name: "nodePort (only) should be deleted from all spec.ports",
 			obj: NewTestUnstructured().WithName("svc-1").