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/error.go

@@ -0,0 +1,113 @@
+/*
+Copyright 2014 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"
+)
+
+type notRegisteredErr struct {
+	gvk    schema.GroupVersionKind
+	target GroupVersioner
+	t      reflect.Type
+}
+
+func NewNotRegisteredErrForKind(gvk schema.GroupVersionKind) error {
+	return &notRegisteredErr{gvk: gvk}
+}
+
+func NewNotRegisteredErrForType(t reflect.Type) error {
+	return &notRegisteredErr{t: t}
+}
+
+func NewNotRegisteredErrForTarget(t reflect.Type, target GroupVersioner) error {
+	return &notRegisteredErr{t: t, target: target}
+}
+
+func (k *notRegisteredErr) Error() string {
+	if k.t != nil && k.target != nil {
+		return fmt.Sprintf("%v is not suitable for converting to %q", k.t, k.target)
+	}
+	if k.t != nil {
+		return fmt.Sprintf("no kind is registered for the type %v", k.t)
+	}
+	if len(k.gvk.Kind) == 0 {
+		return fmt.Sprintf("no version %q has been registered", k.gvk.GroupVersion())
+	}
+	if k.gvk.Version == APIVersionInternal {
+		return fmt.Sprintf("no kind %q is registered for the internal version of group %q", k.gvk.Kind, k.gvk.Group)
+	}
+
+	return fmt.Sprintf("no kind %q is registered for version %q", k.gvk.Kind, k.gvk.GroupVersion())
+}
+
+// IsNotRegisteredError returns true if the error indicates the provided
+// object or input data is not registered.
+func IsNotRegisteredError(err error) bool {
+	if err == nil {
+		return false
+	}
+	_, ok := err.(*notRegisteredErr)
+	return ok
+}
+
+type missingKindErr struct {
+	data string
+}
+
+func NewMissingKindErr(data string) error {
+	return &missingKindErr{data}
+}
+
+func (k *missingKindErr) Error() string {
+	return fmt.Sprintf("Object 'Kind' is missing in '%s'", k.data)
+}
+
+// IsMissingKind returns true if the error indicates that the provided object
+// is missing a 'Kind' field.
+func IsMissingKind(err error) bool {
+	if err == nil {
+		return false
+	}
+	_, ok := err.(*missingKindErr)
+	return ok
+}
+
+type missingVersionErr struct {
+	data string
+}
+
+// IsMissingVersion returns true if the error indicates that the provided object
+// is missing a 'Version' field.
+func NewMissingVersionErr(data string) error {
+	return &missingVersionErr{data}
+}
+
+func (k *missingVersionErr) Error() string {
+	return fmt.Sprintf("Object 'apiVersion' is missing in '%s'", k.data)
+}
+
+func IsMissingVersion(err error) bool {
+	if err == nil {
+		return false
+	}
+	_, ok := err.(*missingVersionErr)
+	return ok
+}