Remove remaining plugins packages from external API.

api/internal/plugins/builtinconfig/namebackreferences.go

@@ -0,0 +1,93 @@
+// Copyright 2019 The Kubernetes Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+package builtinconfig
+
+import (
+	"strings"
+
+	"sigs.k8s.io/kustomize/api/resid"
+	"sigs.k8s.io/kustomize/api/types"
+)
+
+// NameBackReferences is an association between a gvk.GVK and a list
+// of FieldSpec instances that could refer to it.
+//
+// It is used to handle name changes, and can be thought of as a
+// a contact list.  If you change your own contact info (name,
+// phone number, etc.), you must tell your contacts or they won't
+// know about the change.
+//
+// For example, ConfigMaps can be used by Pods and everything that
+// contains a Pod; Deployment, Job, StatefulSet, etc.  To change
+// the name of a ConfigMap instance from 'alice' to 'bob', one
+// must visit all objects that could refer to the ConfigMap, see if
+// they mention 'alice', and if so, change the reference to 'bob'.
+//
+// The NameBackReferences instance to aid in this could look like
+//   {
+//     kind: ConfigMap
+//     version: v1
+//     FieldSpecs:
+//     - kind: Pod
+//       version: v1
+//       path: spec/volumes/configMap/name
+//     - kind: Deployment
+//       path: spec/template/spec/volumes/configMap/name
+//     - kind: Job
+//       path: spec/template/spec/volumes/configMap/name
+//       (etc.)
+//   }
+type NameBackReferences struct {
+	resid.Gvk  `json:",inline,omitempty" yaml:",inline,omitempty"`
+	FieldSpecs types.FsSlice `json:"FieldSpecs,omitempty" yaml:"FieldSpecs,omitempty"`
+}
+
+func (n NameBackReferences) String() string {
+	var r []string
+	for _, f := range n.FieldSpecs {
+		r = append(r, f.String())
+	}
+	return n.Gvk.String() + ":  (\n" +
+		strings.Join(r, "\n") + "\n)"
+}
+
+type nbrSlice []NameBackReferences
+
+func (s nbrSlice) Len() int      { return len(s) }
+func (s nbrSlice) Swap(i, j int) { s[i], s[j] = s[j], s[i] }
+func (s nbrSlice) Less(i, j int) bool {
+	return s[i].Gvk.IsLessThan(s[j].Gvk)
+}
+
+func (s nbrSlice) mergeAll(o nbrSlice) (result nbrSlice, err error) {
+	result = s
+	for _, r := range o {
+		result, err = result.mergeOne(r)
+		if err != nil {
+			return nil, err
+		}
+	}
+	return result, nil
+}
+
+func (s nbrSlice) mergeOne(other NameBackReferences) (nbrSlice, error) {
+	var result nbrSlice
+	var err error
+	found := false
+	for _, c := range s {
+		if c.Gvk.Equals(other.Gvk) {
+			c.FieldSpecs, err = c.FieldSpecs.MergeAll(other.FieldSpecs)
+			if err != nil {
+				return nil, err
+			}
+			found = true
+		}
+		result = append(result, c)
+	}
+
+	if !found {
+		result = append(result, other)
+	}
+	return result, nil
+}