Define a plugin compiler.

pkg/commands/commands.go

@@ -42,7 +42,7 @@ func NewDefaultCommand() *cobra.Command {
 	stdOut := os.Stdout
 
 	c := &cobra.Command{
-		Use:   pgmconfig.PgmName,
+		Use:   pgmconfig.ProgramName,
 		Short: "Manages declarative configuration of Kubernetes",
 		Long: `
 Manages declarative configuration of Kubernetes.

pkg/pgmconfig/config.go

@@ -34,12 +34,12 @@ func ConfigRoot() string {
 	dir := os.Getenv(XDG_CONFIG_HOME)
 	if len(dir) == 0 {
 		dir = filepath.Join(
-			homeDir(), defaultConfigSubdir)
+			HomeDir(), defaultConfigSubdir)
 	}
-	return filepath.Join(dir, PgmName)
+	return filepath.Join(dir, ProgramName)
 }
 
-func homeDir() string {
+func HomeDir() string {
 	home := os.Getenv(homeEnv())
 	if len(home) > 0 {
 		return home

pkg/pgmconfig/config_test.go

@@ -34,7 +34,7 @@ func TestConfigDirNoXdg(t *testing.T) {
 	}
 	if !strings.HasSuffix(
 		s,
-		rootedPath(defaultConfigSubdir, PgmName)) {
+		rootedPath(defaultConfigSubdir, ProgramName)) {
 		t.Fatalf("unexpected config dir: %s", s)
 	}
 }
@@ -50,7 +50,7 @@ func TestConfigDirWithXdg(t *testing.T) {
 	if isSet {
 		os.Setenv(XDG_CONFIG_HOME, xdg)
 	}
-	if s != rootedPath("blah", PgmName) {
+	if s != rootedPath("blah", ProgramName) {
 		t.Fatalf("unexpected config dir: %s", s)
 	}
 }

pkg/pgmconfig/constants.go

@@ -28,6 +28,9 @@ var KustomizationFileNames = []string{
 }
 
 const (
-	PgmName = "kustomize"
-	Repo    = "sigs.k8s.io"
+	// Program name, for help, finding the XDG_CONFIG_DIR, etc.
+	ProgramName = "kustomize"
+	// Domain from which kustomize code is imported, for locating
+	// plugin source code under $GOPATH.
+	DomainName = "sigs.k8s.io"
 )

pkg/plugins/compiler.go

@@ -0,0 +1,146 @@
+/*
+Copyright 2019 The Kubernetes Authors.
+ Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+     http://www.apache.org/licenses/LICENSE-2.0
+ Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package plugins
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"time"
+
+	"sigs.k8s.io/kustomize/k8sdeps/kv/plugin"
+	"sigs.k8s.io/kustomize/pkg/pgmconfig"
+)
+
+// Compiler creates Go plugin object files.
+//
+// Source code is read from
+//   ${srcRoot}/${g}/${v}/${k}.go
+//
+// Object code is written to
+//   ${objRoot}/${g}/${v}/${k}.so
+type Compiler struct {
+	srcRoot string
+	objRoot string
+}
+
+// DefaultSrcRoot guesses where the user
+// has her ${g}/${v}/${k}.go files.
+func DefaultSrcRoot() (string, error) {
+	var nope []string
+	var root string
+
+	root = filepath.Join(
+		os.Getenv("GOPATH"), "src",
+		pgmconfig.DomainName,
+		pgmconfig.ProgramName, plugin.PluginRoot)
+	if FileExists(root) {
+		return root, nil
+	}
+	nope = append(nope, root)
+
+	root = filepath.Join(
+		pgmconfig.ConfigRoot(), plugin.PluginRoot)
+	if FileExists(root) {
+		return root, nil
+	}
+	nope = append(nope, root)
+
+	root = filepath.Join(
+		pgmconfig.HomeDir(),
+		pgmconfig.ProgramName, plugin.PluginRoot)
+	if FileExists(root) {
+		return root, nil
+	}
+	nope = append(nope, root)
+
+	return "", fmt.Errorf(
+		"no default src root; tried %v", nope)
+}
+
+// NewCompiler returns a new compiler instance.
+func NewCompiler(srcRoot, objRoot string) *Compiler {
+	return &Compiler{srcRoot: srcRoot, objRoot: objRoot}
+}
+
+// ObjRoot is root of compilation target tree.
+func (b *Compiler) ObjRoot() string {
+	return b.objRoot
+}
+
+func goBin() string {
+	return filepath.Join(os.Getenv("GOROOT"), "bin", "go")
+}
+
+// Compile reads ${srcRoot}/${g}/${v}/${k}.go
+//    and writes ${objRoot}/${g}/${v}/${k}.so
+func (b *Compiler) Compile(g, v, k string) error {
+	objDir := filepath.Join(b.objRoot, g, v)
+	objFile := filepath.Join(objDir, k) + ".so"
+	if RecentFileExists(objFile) {
+		// Skip rebuilding it.
+		return nil
+	}
+	err := os.MkdirAll(objDir, os.ModePerm)
+	if err != nil {
+		return err
+	}
+	srcFile := filepath.Join(b.srcRoot, g, v, k) + ".go"
+	if !FileExists(srcFile) {
+		return fmt.Errorf(
+			"cannot find source %s", srcFile)
+	}
+	commands := []string{
+		"build",
+		"-buildmode",
+		"plugin",
+		"-tags=plugin",
+		"-o", objFile, srcFile,
+	}
+	goBin := goBin()
+	if !FileExists(goBin) {
+		return fmt.Errorf(
+			"cannot find go compiler %s", goBin)
+	}
+	cmd := exec.Command(goBin, commands...)
+	cmd.Env = os.Environ()
+	if err := cmd.Run(); err != nil {
+		return fmt.Errorf(
+			"compiler error building %s: %v", srcFile, err)
+	}
+	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 {
+	fi, err := os.Stat(path)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return false
+		}
+	}
+	age := time.Now().Sub(fi.ModTime())
+	return age.Minutes() < 3
+}
+
+func FileExists(name string) bool {
+	if _, err := os.Stat(name); err != nil {
+		if os.IsNotExist(err) {
+			return false
+		}
+	}
+	return true
+}

pkg/plugins/compiler_test.go

@@ -0,0 +1,60 @@
+/*
+Copyright 2019 The Kubernetes Authors.
+ Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+     http://www.apache.org/licenses/LICENSE-2.0
+ Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package plugins_test
+
+import (
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"testing"
+
+	. "sigs.k8s.io/kustomize/pkg/plugins"
+)
+
+// Regression coverage over compiler behavior.
+func TestCompiler(t *testing.T) {
+	configRoot, err := ioutil.TempDir("", "kustomize-compiler-test")
+	if err != nil {
+		t.Errorf("failed to make temp dir: %v", err)
+	}
+	srcRoot, err := DefaultSrcRoot()
+	if err != nil {
+		t.Error(err)
+	}
+	c := NewCompiler(srcRoot, configRoot)
+	if configRoot != c.ObjRoot() {
+		t.Errorf("unexpected objRoot %s", c.ObjRoot())
+	}
+	expectObj := filepath.Join(
+		c.ObjRoot(),
+		"someteam.example.com", "v1", "DatePrefixer.so")
+	if FileExists(expectObj) {
+		t.Errorf("obj file should not exist yet: %s", expectObj)
+	}
+	err = c.Compile("someteam.example.com", "v1", "DatePrefixer")
+	if err != nil {
+		t.Error(err)
+	}
+	if !RecentFileExists(expectObj) {
+		t.Errorf("didn't find expected obj file %s", expectObj)
+	}
+	err = os.RemoveAll(c.ObjRoot())
+	if err != nil {
+		t.Errorf(
+			"removing temp dir: %s %v", c.ObjRoot(), err)
+	}
+	if FileExists(expectObj) {
+		t.Errorf("cleanup failed; still see: %s", expectObj)
+	}
+}

pkg/plugins/transformers.go

@@ -77,12 +77,13 @@ func loadAndConfigurePlugin(
 	fileName string, res *resource.Resource) (Configurable, error) {
 	goPlugin, err := plugin.Open(fileName)
 	if err != nil {
-		return nil, fmt.Errorf("plugin %s file not opened", fileName)
+		return nil, errors.Wrapf(err, "plugin %s fails to load", fileName)
 	}
 	symbol, err := goPlugin.Lookup(kplugin.PluginSymbol)
 	if err != nil {
-		return nil, fmt.Errorf(
-			"plugin %s doesn't have symbol %s", fileName, kplugin.PluginSymbol)
+		return nil, errors.Wrapf(
+			err, "plugin %s doesn't have symbol %s",
+			fileName, kplugin.PluginSymbol)
 	}
 	c, ok := symbol.(Configurable)
 	if !ok {

pkg/target/kusttarget.go

@@ -233,6 +233,7 @@ func (kt *KustTarget) generateFromPlugins(
 	generators, err := kt.loadGeneratorPlugins()
 	if err != nil {
 		errs.Append(err)
+		return
 	}
 	for _, g := range generators {
 		resMap, err := g.Generate()

pkg/target/testenvcontroller_test.go

@@ -16,22 +16,22 @@ package target_test
 import (
 	"io/ioutil"
 	"os"
-	"os/exec"
 	"path/filepath"
-	"testing"
-	"time"
-
 	"sigs.k8s.io/kustomize/k8sdeps/kv/plugin"
+	"testing"
+
 	"sigs.k8s.io/kustomize/pkg/pgmconfig"
+	"sigs.k8s.io/kustomize/pkg/plugins"
 )
 
 // TestEnvController manages the KustTarget test environment.
 // It sets/resets XDG_CONFIG_HOME, makes/removes a temp objRoot.
 type TestEnvController struct {
-	t             *testing.T
-	xdgConfigHome string
-	oldXdg        string
-	wasSet        bool
+	t        *testing.T
+	compiler *plugins.Compiler
+	workDir  string
+	oldXdg   string
+	wasSet   bool
 }
 
 func NewTestEnvController(t *testing.T) *TestEnvController {
@@ -39,121 +39,62 @@ func NewTestEnvController(t *testing.T) *TestEnvController {
 }
 
 func (x *TestEnvController) Set() *TestEnvController {
-	x.makeTmpConfigHomeDir()
-	x.makeObjectRootDir()
+	x.createWorkDir()
+	x.compiler = x.makeCompiler()
 	x.setEnv()
 	return x
 }
 
 func (x *TestEnvController) Reset() {
 	x.resetEnv()
-	x.removeTmpConfigHomeDir()
+	x.removeWorkDir()
 }
 
-func (x *TestEnvController) fileExists(name string) bool {
-	if _, err := os.Stat(name); err != nil {
-		if os.IsNotExist(err) {
-			return false
-		}
-	}
-	return true
-}
-
-func (x *TestEnvController) recentFileExists(path string) bool {
-	fi, err := os.Stat(path)
+func (x *TestEnvController) BuildGoPlugin(g, v, k string) {
+	err := x.compiler.Compile(g, v, k)
 	if err != nil {
-		if os.IsNotExist(err) {
-			return false
-		}
-	}
-	age := time.Now().Sub(fi.ModTime())
-	return age.Minutes() < 1
-}
-
-func (x *TestEnvController) BuildGoPlugin(plugin ...string) {
-	obj := filepath.Join(
-		append([]string{x.ObjectRoot()}, plugin...)...) + ".so"
-	if x.recentFileExists(obj) {
-		// Skip rebuilding it.
-		return
-	}
-	src := filepath.Join(
-		append([]string{x.SrcRoot()}, plugin...)...) + ".go"
-	if !x.fileExists(src) {
-		x.t.Errorf("cannot find go plugin source %s", src)
-	}
-	commands := []string{
-		"build",
-		"-buildmode",
-		"plugin",
-		"-tags=plugin",
-		"-o", obj, src,
-	}
-	goBin := filepath.Join(os.Getenv("GOROOT"), "bin", "go")
-	if !x.fileExists(src) {
-		x.t.Errorf("cannot find go compiler %s", goBin)
-	}
-	cmd := exec.Command(goBin, commands...)
-	cmd.Env = os.Environ()
-	// cmd.Dir = filepath.Join(dir, "kustomize", "plugins")
-
-	if err := cmd.Run(); err != nil {
-		x.t.Errorf("compiler error building %s: %v", src, err)
+		x.t.Errorf("compile failed: %v", err)
 	}
 }
 
-// ObjectRoot is the objRoot dir for plugin object files.
-func (x *TestEnvController) ObjectRoot() string {
-	return filepath.Join(
-		x.xdgConfigHome, pgmconfig.PgmName, plugin.PluginRoot)
-}
-
-// SrcRoot is a objRoot directory for plugin source code
-// used by tests.
-//
-// Plugin object code files have to be in a particular
-// location to be found and loaded for security reasons,
-// but placement of plugin source code is up to the user.
-//
-// This function returns a location for storing example
-// plugins for tests.  And maybe builtins at some point.
-func (x *TestEnvController) SrcRoot() string {
-	dir := filepath.Join(
-		os.Getenv("GOPATH"), "src",
-		pgmconfig.Repo, pgmconfig.PgmName, plugin.PluginRoot)
-	if _, err := os.Stat(dir); err != nil {
-		x.t.Errorf("plugin source objRoot '%s' not found", dir)
+func (x *TestEnvController) makeCompiler() *plugins.Compiler {
+	// The plugin loader wants to find object code under
+	//    $XDG_CONFIG_HOME/kustomize/plugins
+	// and the compiler writes object code to
+	//    $objRoot
+	// so set things up accordingly.
+	objRoot := filepath.Join(
+		x.workDir, pgmconfig.ProgramName, plugin.PluginRoot)
+	err := os.MkdirAll(objRoot, os.ModePerm)
+	if err != nil {
+		x.t.Error(err)
 	}
-	return dir
+	srcRoot, err := plugins.DefaultSrcRoot()
+	if err != nil {
+		x.t.Error(err)
+	}
+	return plugins.NewCompiler(srcRoot, objRoot)
 }
 
-func (x *TestEnvController) makeTmpConfigHomeDir() {
+func (x *TestEnvController) createWorkDir() {
 	var err error
-	x.xdgConfigHome, err = ioutil.TempDir("", "kustomizetests")
+	x.workDir, err = ioutil.TempDir("", "kustomize-plugin-tests")
 	if err != nil {
-		x.t.Errorf("failed to make temp objRoot: %v", err)
+		x.t.Errorf("failed to make work dir: %v", err)
 	}
 }
 
-func (x *TestEnvController) makeObjectRootDir() {
-	err := os.MkdirAll(x.ObjectRoot(), os.ModePerm)
+func (x *TestEnvController) removeWorkDir() {
+	err := os.RemoveAll(x.workDir)
 	if err != nil {
 		x.t.Errorf(
-			"making temp object objRoot %s: %v", x.ObjectRoot(), err)
-	}
-}
-
-func (x *TestEnvController) removeTmpConfigHomeDir() {
-	err := os.RemoveAll(x.xdgConfigHome)
-	if err != nil {
-		x.t.Errorf(
-			"removing temp object objRoot: %s %v", x.xdgConfigHome, err)
+			"removing work dir: %s %v", x.workDir, err)
 	}
 }
 
 func (x *TestEnvController) setEnv() {
 	x.oldXdg, x.wasSet = os.LookupEnv(pgmconfig.XDG_CONFIG_HOME)
-	os.Setenv(pgmconfig.XDG_CONFIG_HOME, x.xdgConfigHome)
+	os.Setenv(pgmconfig.XDG_CONFIG_HOME, x.workDir)
 }
 
 func (x *TestEnvController) resetEnv() {