add application controller (#2652)

Signed-off-by: Jeff <zw0948@gmail.com>

vendor/sigs.k8s.io/controller-runtime/pkg/webhook/conversion/decoder.go

@@ -0,0 +1,31 @@
+package conversion
+
+import (
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/apimachinery/pkg/runtime/serializer"
+)
+
+// Decoder knows how to decode the contents of a CRD version conversion
+// request into a concrete object.
+// TODO(droot): consider reusing decoder from admission pkg for this.
+type Decoder struct {
+	codecs serializer.CodecFactory
+}
+
+// NewDecoder creates a Decoder given the runtime.Scheme
+func NewDecoder(scheme *runtime.Scheme) (*Decoder, error) {
+	return &Decoder{codecs: serializer.NewCodecFactory(scheme)}, nil
+}
+
+// Decode decodes the inlined object.
+func (d *Decoder) Decode(content []byte) (runtime.Object, *schema.GroupVersionKind, error) {
+	deserializer := d.codecs.UniversalDeserializer()
+	return deserializer.Decode(content, nil, nil)
+}
+
+// DecodeInto decodes the inlined object in the into the passed-in runtime.Object.
+func (d *Decoder) DecodeInto(content []byte, into runtime.Object) error {
+	deserializer := d.codecs.UniversalDeserializer()
+	return runtime.DecodeInto(deserializer, content, into)
+}