Move plugin config to main config package.

api/pgmconfig/pluginconfig.go

@@ -0,0 +1,96 @@
+// Copyright 2019 The Kubernetes Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+package pgmconfig
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"runtime"
+
+	"github.com/spf13/pflag"
+	"sigs.k8s.io/kustomize/api/types"
+)
+
+const (
+	// Symbol that must be used inside Go plugins.
+	PluginSymbol = "KustomizePlugin"
+
+	// Location of builtins.
+	BuiltinPluginPackage = "builtin"
+
+	// The value of kubernetes ApiVersion to use in configuration
+	// files for builtin plugins.
+	// The value for non-builtins can be anything.
+	BuiltinPluginApiVersion = BuiltinPluginPackage
+
+	// Domain from which kustomize code is imported, for locating
+	// plugin source code under $GOPATH when GOPATH is defined.
+	DomainName = "sigs.k8s.io"
+
+	// Name of directory housing all plugins.
+	PluginRoot = "plugin"
+
+	flagEnablePluginsName = "enable_alpha_plugins"
+	flagEnablePluginsHelp = `enable plugins, an alpha feature.
+See https://github.com/kubernetes-sigs/kustomize/blob/master/docs/plugins/README.md
+`
+	flagErrorFmt = `
+unable to load external plugin %s because plugins disabled
+specify the flag
+  --%s
+to %s`
+)
+
+func ActivePluginConfig() *types.PluginConfig {
+	pc := DefaultPluginConfig()
+	pc.Enabled = true
+	return pc
+}
+
+func DefaultPluginConfig() *types.PluginConfig {
+	return &types.PluginConfig{
+		Enabled:       false,
+		DirectoryPath: filepath.Join(configRoot(), PluginRoot),
+	}
+}
+
+func NotEnabledErr(name string) error {
+	return fmt.Errorf(
+		flagErrorFmt,
+		name,
+		flagEnablePluginsName,
+		flagEnablePluginsHelp)
+}
+
+func AddFlagEnablePlugins(set *pflag.FlagSet, v *bool) {
+	set.BoolVar(
+		v, flagEnablePluginsName,
+		false, flagEnablePluginsHelp)
+}
+
+// Use https://github.com/kirsle/configdir instead?
+func configRoot() string {
+	dir := os.Getenv(XdgConfigHomeEnv)
+	if len(dir) == 0 {
+		dir = filepath.Join(
+			HomeDir(), XdgConfigHomeEnvDefault)
+	}
+	return filepath.Join(dir, ProgramName)
+}
+
+func HomeDir() string {
+	home := os.Getenv(homeEnv())
+	if len(home) > 0 {
+		return home
+	}
+	return "~"
+}
+
+func homeEnv() string {
+	if runtime.GOOS == "windows" {
+		return "USERPROFILE"
+	}
+	return "HOME"
+}