Merge pull request #52753 from munnerz/sample-controller

Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

sample-controller: add example CRD controller

**What this PR does / why we need it**:

Adds a sample-controller example repository

fixes #52752

**Special notes for your reviewer**:

This is currently based on the sttts:sttts-codegen-scripts branch and should not be merged until that is (ref https://github.com/kubernetes/kubernetes/pull/52186)

**Release note**:

```
Add sample-controller repository
```

/cc @sttts @nikhita @colemickens

Kubernetes-commit: 9a7800f7d2efb88b397674672ac56f898826cf7c

vendor/k8s.io/apimachinery/pkg/runtime/codec_check.go

@@ -0,0 +1,48 @@
+/*
+Copyright 2016 The Kubernetes Authors.
+
+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
+
+import (
+	"fmt"
+	"reflect"
+
+	"k8s.io/apimachinery/pkg/runtime/schema"
+)
+
+// CheckCodec makes sure that the codec can encode objects like internalType,
+// decode all of the external types listed, and also decode them into the given
+// object. (Will modify internalObject.) (Assumes JSON serialization.)
+// TODO: verify that the correct external version is chosen on encode...
+func CheckCodec(c Codec, internalType Object, externalTypes ...schema.GroupVersionKind) error {
+	if _, err := Encode(c, internalType); err != nil {
+		return fmt.Errorf("Internal type not encodable: %v", err)
+	}
+	for _, et := range externalTypes {
+		exBytes := []byte(fmt.Sprintf(`{"kind":"%v","apiVersion":"%v"}`, et.Kind, et.GroupVersion().String()))
+		obj, err := Decode(c, exBytes)
+		if err != nil {
+			return fmt.Errorf("external type %s not interpretable: %v", et, err)
+		}
+		if reflect.TypeOf(obj) != reflect.TypeOf(internalType) {
+			return fmt.Errorf("decode of external type %s produced: %#v", et, obj)
+		}
+		if err = DecodeInto(c, exBytes, internalType); err != nil {
+			return fmt.Errorf("external type %s not convertible to internal type: %v", et, err)
+		}
+	}
+	return nil
+}