Do not automatically decode runtime.RawExtension

Make clients opt in to decoding objects that are stored
in the generic api.List object by invoking runtime.DecodeList()
with a set of schemes. Makes it easier to handle unknown
schema objects because decoding is in the control of the code.

Add runtime.Unstructured, which is a simple in memory
representation of an external object.

pkg/runtime/unstructured_test.go

@@ -0,0 +1,44 @@
+/*
+Copyright 2014 Google Inc. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package runtime_test
+
+import (
+	"testing"
+
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/runtime"
+)
+
+func TestDecodeUnstructured(t *testing.T) {
+	pl := &api.List{
+		Items: []runtime.Object{
+			&api.Pod{ObjectMeta: api.ObjectMeta{Name: "1"}},
+			&runtime.Unknown{TypeMeta: runtime.TypeMeta{Kind: "Pod", APIVersion: "v1beta3"}, RawJSON: []byte(`{"kind":"Pod","apiVersion":"v1beta3","metadata":{"name":"test"}}`)},
+			&runtime.Unknown{TypeMeta: runtime.TypeMeta{Kind: "", APIVersion: "v1beta3"}, RawJSON: []byte(`{"kind":"Pod","apiVersion":"v1beta3","metadata":{"name":"test"}}`)},
+			&runtime.Unstructured{TypeMeta: runtime.TypeMeta{Kind: "Foo", APIVersion: "Bar"}, Object: map[string]interface{}{"test": "value"}},
+		},
+	}
+	if errs := runtime.DecodeList(pl.Items, runtime.UnstructuredJSONScheme); len(errs) == 1 {
+		t.Fatalf("unexpected error %v", errs)
+	}
+	if pod, ok := pl.Items[1].(*runtime.Unstructured); !ok || pod.Object["kind"] != "Pod" || pod.Object["metadata"].(map[string]interface{})["name"] != "test" {
+		t.Errorf("object not converted: %#v", pl.Items[1])
+	}
+	if _, ok := pl.Items[2].(*runtime.Unknown); !ok {
+		t.Errorf("object should not have been converted: %#v", pl.Items[2])
+	}
+}