Simplify plugin loader code.

* use one place to build plugin file names,
 * use one loader instance,
 * test for plugin enabled flag in just one place to
   avoid errors and reduce if statements,
 * don't return private objects,
 * factor goplugin loading to a method,
 * fix a related test that was commented out.

pkg/target/kusttarget.go

@@ -44,7 +44,7 @@ type KustTarget struct {
 	ldr           ifc.Loader
 	rFactory      *resmap.Factory
 	tFactory      transformer.Factory
-	pluginConfig  *types.PluginConfig
+	pLdr          *plugins.Loader
 }
 
 // NewKustTarget returns a new instance of KustTarget primed with a Loader.
@@ -52,7 +52,7 @@ func NewKustTarget(
 	ldr ifc.Loader,
 	rFactory *resmap.Factory,
 	tFactory transformer.Factory,
-	pc *types.PluginConfig) (*KustTarget, error) {
+	pLdr *plugins.Loader) (*KustTarget, error) {
 	content, err := loadKustFile(ldr)
 	if err != nil {
 		return nil, err
@@ -74,7 +74,7 @@ func NewKustTarget(
 		ldr:           ldr,
 		rFactory:      rFactory,
 		tFactory:      tFactory,
-		pluginConfig:  pc,
+		pLdr:          pLdr,
 	}, nil
 }
 
@@ -240,11 +240,9 @@ func (kt *KustTarget) AccumulateTarget() (
 		return nil, errors.Wrap(
 			err, "merging legacy configMaps and secrets")
 	}
-	if kt.pluginConfig.GoEnabled {
-		err := kt.generateFromPlugins(ra)
-		if err != nil {
-			return nil, err
-		}
+	err = kt.generateFromPlugins(ra)
+	if err != nil {
+		return nil, err
 	}
 	patches, err := kt.rFactory.RF().SliceFromPatches(
 		kt.ldr, kt.kustomization.PatchesStrategicMerge)
@@ -328,7 +326,7 @@ func (kt *KustTarget) accumulateDirectory(
 	ra *accumulator.ResAccumulator, ldr ifc.Loader, path string) error {
 	defer ldr.Cleanup()
 	subKt, err := NewKustTarget(
-		ldr, kt.rFactory, kt.tFactory, kt.pluginConfig)
+		ldr, kt.rFactory, kt.tFactory, kt.pLdr)
 	if err != nil {
 		return errors.Wrapf(err, "couldn't make target for path '%s'", path)
 	}
@@ -403,14 +401,11 @@ func (kt *KustTarget) newTransformer(
 		return nil, err
 	}
 	r = append(r, t)
-
-	if kt.pluginConfig.GoEnabled {
-		tp, err := kt.loadTransformerPlugins()
-		if err != nil {
-			return nil, err
-		}
-		r = append(r, tp...)
+	tp, err := kt.loadTransformerPlugins()
+	if err != nil {
+		return nil, err
 	}
+	r = append(r, tp...)
 	return transformers.NewMultiTransformer(r), nil
 }
 
@@ -420,8 +415,7 @@ func (kt *KustTarget) loadTransformerPlugins() ([]transformers.Transformer, erro
 	if err != nil {
 		return nil, err
 	}
-	return plugins.NewTransformerLoader(
-		kt.pluginConfig, kt.ldr, kt.rFactory).Load(ra.ResMap())
+	return kt.pLdr.LoadTransformers(kt.ldr, ra.ResMap())
 }
 
 func (kt *KustTarget) loadGeneratorPlugins() ([]transformers.Generator, error) {
@@ -430,6 +424,5 @@ func (kt *KustTarget) loadGeneratorPlugins() ([]transformers.Generator, error) {
 	if err != nil {
 		return nil, err
 	}
-	return plugins.NewGeneratorLoader(
-		kt.pluginConfig, kt.ldr, kt.rFactory).Load(ra.ResMap())
+	return kt.pLdr.LoadGenerators(kt.ldr, ra.ResMap())
 }

pkg/target/kusttarget_test.go

@@ -23,7 +23,6 @@ import (
 	"strings"
 	"testing"
 
-	"sigs.k8s.io/kustomize/k8sdeps/kv/plugin"
 	"sigs.k8s.io/kustomize/pkg/gvk"
 	"sigs.k8s.io/kustomize/pkg/ifc"
 	"sigs.k8s.io/kustomize/pkg/internal/loadertest"
@@ -206,8 +205,7 @@ func TestResources(t *testing.T) {
 
 func TestKustomizationNotFound(t *testing.T) {
 	_, err := NewKustTarget(
-		loadertest.NewFakeLoader("/foo"),
-		nil, nil, plugin.DefaultPluginConfig())
+		loadertest.NewFakeLoader("/foo"), nil, nil, nil)
 	if err == nil {
 		t.Fatalf("expected an error")
 	}

pkg/target/kusttestharness_test.go

@@ -30,6 +30,7 @@ import (
 	"sigs.k8s.io/kustomize/pkg/internal/loadertest"
 	"sigs.k8s.io/kustomize/pkg/loader"
 	"sigs.k8s.io/kustomize/pkg/pgmconfig"
+	"sigs.k8s.io/kustomize/pkg/plugins"
 	"sigs.k8s.io/kustomize/pkg/resmap"
 	"sigs.k8s.io/kustomize/pkg/resource"
 	. "sigs.k8s.io/kustomize/pkg/target"
@@ -41,7 +42,7 @@ type KustTestHarness struct {
 	t   *testing.T
 	rf  *resmap.Factory
 	ldr loadertest.FakeLoader
-	pc  *types.PluginConfig
+	pl  *plugins.Loader
 }
 
 func NewKustTestHarness(t *testing.T, path string) *KustTestHarness {
@@ -58,18 +59,19 @@ func NewKustTestHarnessWithPluginConfig(
 func NewKustTestHarnessFull(
 	t *testing.T, path string,
 	lr loader.LoadRestrictorFunc, pc *types.PluginConfig) *KustTestHarness {
+	rf := resmap.NewFactory(resource.NewFactory(
+		kunstruct.NewKunstructuredFactoryWithGeneratorArgs(
+			&types.GeneratorMetaArgs{PluginConfig: pc})))
 	return &KustTestHarness{
-		t: t,
-		rf: resmap.NewFactory(resource.NewFactory(
-			kunstruct.NewKunstructuredFactoryWithGeneratorArgs(
-				&types.GeneratorMetaArgs{PluginConfig: pc}))),
+		t:   t,
+		rf:  rf,
 		ldr: loadertest.NewFakeLoaderWithRestrictor(lr, path),
-		pc:  pc}
+		pl:  plugins.NewLoader(pc, rf)}
 }
 
 func (th *KustTestHarness) makeKustTarget() *KustTarget {
 	kt, err := NewKustTarget(
-		th.ldr, th.rf, transformer.NewFactoryImpl(), th.pc)
+		th.ldr, th.rf, transformer.NewFactoryImpl(), th.pl)
 	if err != nil {
 		th.t.Fatalf("Unexpected construction error %v", err)
 	}

pkg/target/transformerplugin_test.go

@@ -42,8 +42,7 @@ func writeStringPrefixer(th *KustTestHarness, path string) {
 apiVersion: someteam.example.com/v1
 kind: StringPrefixer
 metadata:
-  name: myStringPrefixer
-prefix: apple-
+  name: apple
 `)
 }
 
@@ -52,7 +51,7 @@ func writeDatePrefixer(th *KustTestHarness, path string) {
 apiVersion: someteam.example.com/v1
 kind: DatePrefixer
 metadata:
-  name: myDatePrefixer
+  name: irrelevant
 `)
 }
 
@@ -73,7 +72,11 @@ resources:
 - deployment.yaml
 transformers:
 - stringPrefixer.yaml
+# - datePrefixer.yaml
 `)
+	// TODO(monopole): assure ordering of loaded
+	// transformers and this will work - the trouble
+	// is we load into a map (ResMap), not a list.
 	writeDeployment(th, "/app/deployment.yaml")
 	writeStringPrefixer(th, "/app/stringPrefixer.yaml")
 	writeDatePrefixer(th, "/app/datePrefixer.yaml")
@@ -144,7 +147,16 @@ metadata:
 `)
 }
 
-func xTestTransformedTransformers(t *testing.T) {
+func TestTransformedTransformers(t *testing.T) {
+	tc := NewTestEnvController(t).Set()
+	defer tc.Reset()
+
+	tc.BuildGoPlugin(
+		"someteam.example.com", "v1", "StringPrefixer")
+
+	tc.BuildGoPlugin(
+		"someteam.example.com", "v1", "DatePrefixer")
+
 	th := NewKustTestHarnessWithPluginConfig(
 		t, "/app/overlay", plugin.ActivePluginConfig())
 
@@ -170,6 +182,18 @@ transformers:
 		t.Fatalf("Err: %v", err)
 	}
 	th.assertActualEqualsExpected(m, `
-HEY
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: 2018-05-11-apple-myDeployment
+spec:
+  template:
+    metadata:
+      labels:
+        backend: awesome
+    spec:
+      containers:
+      - image: whatever
+        name: whatever
 `)
 }