use a field instead of an annotation

api/internal/plugins/fnplugin/fnplugin.go

@@ -187,6 +187,7 @@ func (p *FnPlugin) invokePlugin(input []byte) ([]byte, error) {
 	p.runFns.Input = bytes.NewReader(input)
 	p.runFns.Functions = append(p.runFns.Functions, functionConfig)
 	p.runFns.Output = &ouputBuffer
+	p.runFns.WorkDir = p.h.WorkingDir()
 
 	err = p.runFns.Execute()
 	if err != nil {

api/internal/plugins/loader/loader.go

@@ -47,6 +47,11 @@ func (l *Loader) Config() *types.PluginConfig {
 	return l.pc
 }
 
+// SetWorkDir sets the working directory for this loader's plugins
+func (l *Loader) SetWorkDir(wd string) {
+	l.pc.FnpLoadingOptions.WorkingDir = wd
+}
+
 func (l *Loader) LoadGenerators(
 	ldr ifc.Loader, v ifc.Validator, rm resmap.ResMap) ([]resmap.Generator, error) {
 	var result []resmap.Generator

api/internal/target/kusttarget.go

@@ -21,7 +21,6 @@ import (
 	"sigs.k8s.io/kustomize/api/resmap"
 	"sigs.k8s.io/kustomize/api/resource"
 	"sigs.k8s.io/kustomize/api/types"
-	"sigs.k8s.io/kustomize/kyaml/kio/kioutil"
 	"sigs.k8s.io/kustomize/kyaml/openapi"
 	"sigs.k8s.io/yaml"
 )
@@ -41,11 +40,13 @@ func NewKustTarget(
 	validator ifc.Validator,
 	rFactory *resmap.Factory,
 	pLdr *loader.Loader) *KustTarget {
+	pLdrCopy := *pLdr
+	pLdrCopy.SetWorkDir(ldr.Root())
 	return &KustTarget{
 		ldr:       ldr,
 		validator: validator,
 		rFactory:  rFactory,
-		pLdr:      pLdr,
+		pLdr:      &pLdrCopy,
 	}
 }
 
@@ -263,12 +264,7 @@ func (kt *KustTarget) configureExternalGenerators() ([]resmap.Generator, error)
 	if err != nil {
 		return nil, err
 	}
-	m := ra.ResMap()
-	err = m.AnnotateAll(kioutil.WorkingDirAnnotation, kt.ldr.Root())
-	if err != nil {
-		return nil, err
-	}
-	return kt.pLdr.LoadGenerators(kt.ldr, kt.validator, m)
+	return kt.pLdr.LoadGenerators(kt.ldr, kt.validator, ra.ResMap())
 }
 
 func (kt *KustTarget) runTransformers(ra *accumulator.ResAccumulator) error {
@@ -305,12 +301,7 @@ func (kt *KustTarget) configureExternalTransformers(transformers []string) ([]re
 	if err != nil {
 		return nil, err
 	}
-	m := ra.ResMap()
-	err = m.AnnotateAll(kioutil.WorkingDirAnnotation, kt.ldr.Root())
-	if err != nil {
-		return nil, err
-	}
-	return kt.pLdr.LoadTransformers(kt.ldr, kt.validator, m)
+	return kt.pLdr.LoadTransformers(kt.ldr, kt.validator, ra.ResMap())
 }
 
 func (kt *KustTarget) runValidators(ra *accumulator.ResAccumulator) error {

api/resmap/resmap.go

@@ -66,6 +66,10 @@ func (c *PluginHelpers) Validator() ifc.Validator {
 	return c.v
 }
 
+func (c *PluginHelpers) WorkingDir() string {
+	return c.pc.FnpLoadingOptions.WorkingDir
+}
+
 type GeneratorPlugin interface {
 	Generator
 	Configurable

api/types/pluginrestrictions.go

@@ -57,4 +57,6 @@ type FnPluginLoadingOptions struct {
 	Env []string
 	// Run as uid and gid of the command executor
 	AsCurrentUser bool
+	// Run in this working directory
+	WorkingDir string
 }

kyaml/kio/kioutil/kioutil.go

@@ -25,10 +25,6 @@ const (
 
 	// SeqIndentAnnotation records the sequence nodes indentation of the input resource
 	SeqIndentAnnotation AnnotationKey = "internal.config.kubernetes.io/seqindent"
-
-	// WorkingDirAnnotation records the directory of the kustomization that
-	// refers to the resource
-	WorkingDirAnnotation AnnotationKey = "internal.config.kubernetes.io/working-dir"
 )
 
 func GetFileAnnotations(rn *yaml.RNode) (string, string, error) {

kyaml/runfn/runfn.go

@@ -101,6 +101,10 @@ type RunFns struct {
 	// If it is true, the empty result will be provided as input to the next
 	// function in the list.
 	ContinueOnEmptyResult bool
+
+	// WorkDir specifies which working directory an exec function should run in.
+	// If this is empty, fall back to the current working directory.
+	WorkDir string
 }
 
 // Execute runs the command
@@ -507,13 +511,13 @@ func (r *RunFns) ffp(spec runtimeutil.FunctionSpec, api *yaml.RNode, currentUser
 	}
 
 	if r.EnableExec && spec.Exec.Path != "" {
-		wd, err := getWorkingDirectory(api)
+		wd, err := getWorkingDirectory(r.WorkDir)
 		if err != nil {
 			return nil, err
 		}
 
 		ef := &exec.Filter{
-			Path: spec.Exec.Path,
+			Path:       spec.Exec.Path,
 			WorkingDir: wd,
 		}
 
@@ -527,10 +531,8 @@ func (r *RunFns) ffp(spec runtimeutil.FunctionSpec, api *yaml.RNode, currentUser
 	return nil, nil
 }
 
-func getWorkingDirectory(api *yaml.RNode) (string, error) {
-	annotations := api.GetAnnotations()
-	wd, ok := annotations[kioutil.WorkingDirAnnotation]
-	if !ok {
+func getWorkingDirectory(wd string) (string, error) {
+	if wd == "" {
 		return os.Getwd()
 	}