Plugin loader improvements.

api/internal/plugins/compiler/compiler.go

@@ -119,7 +119,7 @@ func (b *Compiler) Compile(g, v, k string) error {
 	lowK := strings.ToLower(k)
 	objDir := filepath.Join(b.objRoot, g, v, lowK)
 	objFile := filepath.Join(objDir, k) + ".so"
-	if RecentFileExists(objFile) {
+	if FileYoungerThan(objFile, time.Minute) {
 		// Skip rebuilding it.
 		return nil
 	}
@@ -134,7 +134,6 @@ func (b *Compiler) Compile(g, v, k string) error {
 		if !FileExists(s) {
 			return fmt.Errorf(
 				"cannot find source at '%s' or '%s'", srcFile, s)
-
 		}
 		srcFile = s
 	}
@@ -160,17 +159,15 @@ func (b *Compiler) Compile(g, v, k string) error {
 	return nil
 }
 
-// True if file less than 3 minutes old, i.e. not
-// accidentally left over from some earlier build.
-func RecentFileExists(path string) bool {
+// FileYoungerThan returns true if the file age is <= the Duration argument.
+func FileYoungerThan(path string, d time.Duration) bool {
 	fi, err := os.Stat(path)
 	if err != nil {
 		if os.IsNotExist(err) {
 			return false
 		}
 	}
-	age := time.Since(fi.ModTime())
-	return age.Minutes() < 3
+	return time.Since(fi.ModTime()) <= d
 }
 
 func FileExists(name string) bool {

api/internal/plugins/compiler/compiler_test.go

@@ -8,6 +8,7 @@ import (
 	"os"
 	"path/filepath"
 	"testing"
+	"time"
 
 	"sigs.k8s.io/kustomize/api/filesys"
 	. "sigs.k8s.io/kustomize/api/internal/plugins/compiler"
@@ -38,7 +39,7 @@ func TestCompiler(t *testing.T) {
 	if err != nil {
 		t.Error(err)
 	}
-	if !RecentFileExists(expectObj) {
+	if !FileYoungerThan(expectObj, time.Second) {
 		t.Errorf("didn't find expected obj file %s", expectObj)
 	}
 
@@ -52,7 +53,7 @@ func TestCompiler(t *testing.T) {
 	if err != nil {
 		t.Error(err)
 	}
-	if !RecentFileExists(expectObj) {
+	if !FileYoungerThan(expectObj, time.Second) {
 		t.Errorf("didn't find expected obj file %s", expectObj)
 	}
 

api/internal/plugins/loader/loader.go

@@ -22,6 +22,7 @@ import (
 	"sigs.k8s.io/kustomize/api/types"
 )
 
+// Loader loads plugins using a file loader (a different loader).
 type Loader struct {
 	pc *types.PluginConfig
 	rf *resmap.Factory
@@ -107,17 +108,35 @@ func isBuiltinPlugin(res *resource.Resource) bool {
 }
 
 func (l *Loader) loadAndConfigurePlugin(
-	ldr ifc.Loader, v ifc.Validator, res *resource.Resource) (c resmap.Configurable, err error) {
+	ldr ifc.Loader,
+	v ifc.Validator,
+	res *resource.Resource) (c resmap.Configurable, err error) {
 	if isBuiltinPlugin(res) {
-		// Instead of looking for and loading a .so file, just
-		// instantiate the plugin from a generated factory
-		// function (see "pluginator").  Being able to do this
-		// is what makes a plugin "builtin".
-		c, err = l.makeBuiltinPlugin(res.GetGvk())
-	} else if l.pc.PluginRestrictions == types.PluginRestrictionsNone {
-		c, err = l.loadPlugin(res.OrgId())
+		switch l.pc.BpLoadingOptions {
+		case types.BploLoadFromFileSys:
+			c, err = l.loadPlugin(res.OrgId())
+		case types.BploUseStaticallyLinked:
+			// Instead of looking for and loading a .so file,
+			// instantiate the plugin from a generated factory
+			// function (see "pluginator").  Being able to do this
+			// is what makes a plugin "builtin".
+			c, err = l.makeBuiltinPlugin(res.GetGvk())
+		default:
+			err = fmt.Errorf(
+				"unknown plugin loader behavior specified: %v",
+				l.pc.BpLoadingOptions)
+		}
 	} else {
-		err = types.NewErrOnlyBuiltinPluginsAllowed(res.OrgId().Kind)
+		switch l.pc.PluginRestrictions {
+		case types.PluginRestrictionsNone:
+			c, err = l.loadPlugin(res.OrgId())
+		case types.PluginRestrictionsBuiltinsOnly:
+			err = types.NewErrOnlyBuiltinPluginsAllowed(res.OrgId().Kind)
+		default:
+			err = fmt.Errorf(
+				"unknown plugin restriction specified: %v",
+				l.pc.PluginRestrictions)
+		}
 	}
 	if err != nil {
 		return nil, err

api/internal/plugins/loader/loader_test.go

@@ -15,6 +15,7 @@ import (
 	"sigs.k8s.io/kustomize/api/resource"
 	kusttest_test "sigs.k8s.io/kustomize/api/testutils/kusttest"
 	valtest_test "sigs.k8s.io/kustomize/api/testutils/valtest"
+	"sigs.k8s.io/kustomize/api/types"
 )
 
 const (
@@ -58,22 +59,26 @@ func TestLoader(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	c, err := konfig.EnabledPluginConfig()
-	if err != nil {
-		t.Fatal(err)
-	}
-	pLdr := NewLoader(c, rmF)
-	if pLdr == nil {
-		t.Fatal("expect non-nil loader")
-	}
-	m, err := rmF.NewResMapFromBytes([]byte(
+	generatorConfigs, err := rmF.NewResMapFromBytes([]byte(
 		someServiceGenerator + "---\n" + secretGenerator))
 	if err != nil {
 		t.Fatal(err)
 	}
-	_, err = pLdr.LoadGenerators(
-		fLdr, valtest_test.MakeFakeValidator(), m)
-	if err != nil {
-		t.Fatal(err)
+	for _, behavior := range []types.BuiltinPluginLoadingOptions{
+		types.BploUseStaticallyLinked,
+		types.BploLoadFromFileSys} {
+		c, err := konfig.EnabledPluginConfig(behavior)
+		if err != nil {
+			t.Fatal(err)
+		}
+		pLdr := NewLoader(c, rmF)
+		if pLdr == nil {
+			t.Fatal("expect non-nil loader")
+		}
+		_, err = pLdr.LoadGenerators(
+			fLdr, valtest_test.MakeFakeValidator(), generatorConfigs)
+		if err != nil {
+			t.Fatal(err)
+		}
 	}
 }