Isolated content of pkg/kustomize

pkg/transformers/namereference.go

@@ -0,0 +1,110 @@
+/*
+Copyright 2018 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 transformers
+
+import (
+	"errors"
+	"fmt"
+
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/kubectl/pkg/kustomize/resource"
+	"k8s.io/kubectl/pkg/kustomize/types"
+)
+
+// nameReferenceTransformer contains the referencing info between 2 GroupVersionKinds
+type nameReferenceTransformer struct {
+	pathConfigs []referencePathConfig
+}
+
+var _ Transformer = &nameReferenceTransformer{}
+
+// NewDefaultingNameReferenceTransformer constructs a nameReferenceTransformer
+// with defaultNameReferencepathConfigs.
+func NewDefaultingNameReferenceTransformer() (Transformer, error) {
+	return NewNameReferenceTransformer(defaultNameReferencePathConfigs)
+}
+
+// NewNameReferenceTransformer construct a nameReferenceTransformer.
+func NewNameReferenceTransformer(pc []referencePathConfig) (Transformer, error) {
+	if pc == nil {
+		return nil, errors.New("pathConfigs is not expected to be nil")
+	}
+	return &nameReferenceTransformer{pathConfigs: pc}, nil
+}
+
+// Transform does the fields update according to pathConfigs.
+// The old name is in the key in the map and the new name is in the object
+// associated with the key. e.g. if <k, v> is one of the key-value pair in the map,
+// then the old name is k.Name and the new name is v.GetName()
+func (o *nameReferenceTransformer) Transform(
+	m resource.ResourceCollection) error {
+	for GVKn := range m {
+		obj := m[GVKn].Data
+		objMap := obj.UnstructuredContent()
+		for _, referencePathConfig := range o.pathConfigs {
+			for _, path := range referencePathConfig.pathConfigs {
+				if !types.SelectByGVK(GVKn.GVK, path.GroupVersionKind) {
+					continue
+				}
+				err := mutateField(objMap, path.Path, path.CreateIfNotPresent,
+					o.updateNameReference(referencePathConfig.referencedGVK, m))
+				if err != nil {
+					return err
+				}
+			}
+		}
+	}
+	return nil
+}
+
+// noMatchingGVKNError indicates failing to find a gvkn.GroupVersionKindName.
+type noMatchingGVKNError struct {
+	message string
+}
+
+// newNoMatchingGVKNError constructs an instance of noMatchingGVKNError with
+// a given error message.
+func newNoMatchingGVKNError(errMsg string) noMatchingGVKNError {
+	return noMatchingGVKNError{errMsg}
+}
+
+// Error returns the error in string format.
+func (err noMatchingGVKNError) Error() string {
+	return err.message
+}
+
+func (o *nameReferenceTransformer) updateNameReference(
+	GVK schema.GroupVersionKind,
+	m resource.ResourceCollection,
+) func(in interface{}) (interface{}, error) {
+	return func(in interface{}) (interface{}, error) {
+		s, ok := in.(string)
+		if !ok {
+			return nil, fmt.Errorf("%#v is expectd to be %T", in, s)
+		}
+
+		for GVKn, obj := range m {
+			if !types.SelectByGVK(GVKn.GVK, &GVK) {
+				continue
+			}
+			if GVKn.Name == s {
+				return obj.Data.GetName(), nil
+			}
+		}
+		return in, nil
+	}
+}