Make plugin dir match Go conventions.

plugin/builtin/SecretGenerator.go

@@ -0,0 +1,62 @@
+// +build plugin
+
+package main
+
+import (
+	"fmt"
+
+	"sigs.k8s.io/kustomize/pkg/ifc"
+	"sigs.k8s.io/kustomize/pkg/resmap"
+	"sigs.k8s.io/kustomize/pkg/types"
+)
+
+type plugin struct {
+	ldr     ifc.Loader
+	rf      *resmap.Factory
+	options types.GeneratorOptions
+	args    types.SecretArgs
+}
+
+var KustomizePlugin plugin
+
+func (p *plugin) Config(
+	ldr ifc.Loader, rf *resmap.Factory, k ifc.Kunstructured) error {
+	p.ldr = ldr
+	p.rf = rf
+
+	var err error
+	// TODO: Should validate this.
+	p.args.Behavior, err = k.GetFieldValue("behavior")
+	if err != nil {
+		return err
+	}
+
+	envFiles, err := k.GetStringSlice("envFiles")
+	if err != nil {
+		return err
+	}
+	if len(envFiles) > 2 {
+		// TODO: refactor to allow this
+		return fmt.Errorf("cannot yet accept more than one envFile")
+	}
+	if len(envFiles) > 0 {
+		p.args.EnvSource = envFiles[0]
+	}
+
+	p.args.FileSources, err = k.GetStringSlice("valueFiles")
+	if err != nil {
+		return err
+	}
+	p.args.LiteralSources, err = k.GetStringSlice("literals")
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (p *plugin) Generate() (resmap.ResMap, error) {
+	argsList := make([]types.SecretArgs, 1)
+	argsList[0] = p.args
+	return p.rf.NewResMapFromSecretArgs(p.ldr, &p.options, argsList)
+}