modify pluginator to add support for krm function

cmd/pluginator/krmfunction/cmd.go

@@ -0,0 +1,30 @@
+package krmfunction
+
+import (
+	"github.com/spf13/cobra"
+)
+
+// NewKrmFunctionCmd returns a pointer to a command
+func NewKrmFunctionCmd() *cobra.Command {
+	var outputDir string
+	var inputFile string
+
+	cmd := &cobra.Command{
+		Use:   "krm -i FILE -o DIR",
+		Short: "Convert the plugin to KRM function instead of builtin function",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			c := NewConverter(outputDir, inputFile)
+			return c.Convert()
+		},
+	}
+
+	cmd.Flags().StringVarP(&outputDir, "output", "o", "",
+		"Path to the directory which will contain the KRM function")
+	cmd.Flags().StringVarP(&inputFile, "input", "i", "",
+		"Path to the input file")
+
+	cmd.MarkFlagRequired("output")
+	cmd.MarkFlagRequired("input")
+
+	return cmd
+}

cmd/pluginator/krmfunction/converter.go

@@ -0,0 +1,165 @@
+package krmfunction
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"github.com/rakyll/statik/fs"
+	// load embedded func wrapper
+	_ "sigs.k8s.io/kustomize/cmd/pluginator/v2/krmfunction/funcwrapper"
+)
+
+// Converter is a converter to convert the
+// plugin file to KRM function
+type Converter struct {
+	// Path to the output directory
+	outputDir string
+	// Path to the input file
+	inputFile       string
+	wrapperFileName string
+	pluginFileName  string
+	goModFileName   string
+	dockerFileName  string
+}
+
+// NewConverter return a pointer to a new converter
+func NewConverter(outputDir, inputFile string) *Converter {
+	return &Converter{
+		outputDir:       outputDir,
+		inputFile:       inputFile,
+		wrapperFileName: "main.go",
+		pluginFileName:  "plugin.go",
+		goModFileName:   "go.mod",
+		dockerFileName:  "Dockerfile",
+	}
+}
+
+// Convert converts the input file to a executable
+// KRM function and writes to destination directory
+func (c *Converter) Convert() error {
+	// read and process executable wrapper
+	wrapper, err := c.readEmbeddedFile(c.wrapperFileName)
+	if err != nil {
+		return err
+	}
+	wrapper = c.prepareWrapper(wrapper)
+
+	if !strings.HasSuffix(c.inputFile, ".go") {
+		return fmt.Errorf("input file %s is not a Go file", c.inputFile)
+	}
+
+	// read and process plugin code
+	pluginCode, err := c.readDiskFile(c.inputFile)
+	if err != nil {
+		return err
+	}
+	_, c.pluginFileName = filepath.Split(c.inputFile)
+
+	// go.mod file
+	goMod, err := c.readEmbeddedFile(c.goModFileName + ".src")
+	if err != nil {
+		return err
+	}
+
+	// prepare destination directory
+	err = c.mkDstDir()
+	if err != nil {
+		return err
+	}
+
+	// write
+	return c.write(map[string]string{
+		c.wrapperFileName: wrapper,
+		c.pluginFileName:  pluginCode,
+		c.goModFileName:   goMod,
+		c.dockerFileName:  c.getDockerfile(),
+	})
+}
+
+func (c *Converter) getDockerfile() string {
+	return `FROM golang:1.13-stretch
+ENV CGO_ENABLED=0
+WORKDIR /go/src/
+COPY . .
+RUN go build -v -o /usr/local/bin/function ./
+FROM alpine:latest
+COPY --from=0 /usr/local/bin/function /usr/local/bin/function
+CMD ["function"]
+`
+}
+
+func (c *Converter) prepareWrapper(content string) string {
+	b := bytes.NewBufferString(content)
+	o := &bytes.Buffer{}
+	scanner := bufio.NewScanner(b)
+	for scanner.Scan() {
+		line := scanner.Text()
+		// Set the package name to main
+		if strings.TrimSpace(line) == "package funcwrappersrc" {
+			line = "package main"
+		}
+		// assign to plugin variable
+		if strings.TrimSpace(line) == "var plugin resmap.Configurable" {
+			line = line + `
+	// KustomizePlugin is a global variable defined in every plugin
+	plugin = &KustomizePlugin
+`
+		}
+		o.WriteString(line + "\n")
+	}
+	return o.String()
+}
+
+// readEmbeddedFile read the file from embedded files with filename
+// name. Return the file content if it's successful.
+func (c *Converter) readEmbeddedFile(name string) (string, error) {
+	statikFS, err := fs.New()
+	if err != nil {
+		return "", err
+	}
+	r, err := statikFS.Open("/" + name)
+	if err != nil {
+		return "", err
+	}
+	defer r.Close()
+	contents, err := ioutil.ReadAll(r)
+	if err != nil {
+		return "", err
+	}
+
+	return string(contents), nil
+}
+
+func (c *Converter) readDiskFile(path string) (string, error) {
+	f, err := ioutil.ReadFile(path)
+	if err != nil {
+		return "", err
+	}
+	return string(f), nil
+}
+
+func (c *Converter) mkDstDir() error {
+	p := c.outputDir
+	f, err := os.Open(p)
+	if err == nil || f != nil {
+		return fmt.Errorf("directory %s has already existed", p)
+	}
+
+	return os.MkdirAll(p, 0755)
+}
+
+func (c *Converter) write(m map[string]string) error {
+	for k, v := range m {
+		p := filepath.Join(c.outputDir, k)
+		err := ioutil.WriteFile(p, []byte(v), 0644)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}

cmd/pluginator/krmfunction/converter_test.go

@@ -0,0 +1,234 @@
+package krmfunction
+
+import (
+	"bytes"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func makeTempDir(t *testing.T) string {
+	s, err := ioutil.TempDir("", "pluginator-*")
+	assert.NoError(t, err)
+	return s
+}
+
+func getTransformerCode() []byte {
+	// a simple namespace transformer
+	return []byte(`
+package main
+
+import (
+  "fmt"
+
+  "sigs.k8s.io/kustomize/api/resmap"
+  "sigs.k8s.io/yaml"
+  "sigs.k8s.io/kustomize/api/filters/namespace"
+  "sigs.k8s.io/kustomize/kyaml/filtersutil"
+  "sigs.k8s.io/kustomize/api/types"
+)
+
+type plugin struct{
+  Namespace string ` + "`json:\"namespace,omitempty\" yaml:\"namespace,omitempty\"`" + `
+  FieldSpecs       []types.FieldSpec ` + "`json:\"fieldSpecs,omitempty\" yaml:\"fieldSpecs,omitempty\"`" + `
+}
+
+//noinspection GoUnusedGlobalVariable
+var KustomizePlugin plugin
+
+func (p *plugin) Config(
+  _ *resmap.PluginHelpers, config []byte) (err error) {
+  return yaml.Unmarshal(config, p)
+}
+
+func (p *plugin) Transform(rm resmap.ResMap) error {
+  if len(p.Namespace) == 0 {
+    return nil
+  }
+  for _, r := range rm.Resources() {
+    if r.IsEmpty() {
+      // Don't mutate empty objects?
+      continue
+    }
+    err := filtersutil.ApplyToJSON(namespace.Filter{
+      Namespace: p.Namespace,
+      FsSlice:   p.FieldSpecs,
+    }, r)
+    if err != nil {
+      return err
+    }
+    matches := rm.GetMatchingResourcesByCurrentId(r.CurId().Equals)
+    if len(matches) != 1 {
+      return fmt.Errorf(
+        "namespace transformation produces ID conflict: %+v", matches)
+    }
+  }
+  return nil
+}
+`)
+}
+
+func getTransformerInputResource() []byte {
+	return []byte(`
+apiVersion: config.kubernetes.io/v1beta1
+kind: ResourceList
+functionConfig:
+  apiVersion: foo-corp.com/v1
+  kind: FulfillmentCenter
+  metadata:
+    name: staging
+    metadata:
+      annotations:
+        config.kubernetes.io/function: |
+          container:
+            image: gcr.io/example/foo:v1.0.0
+  namespace: foo
+  fieldSpecs:
+  - path: metadata/namespace
+    create: true
+items:
+  - apiVersion: apps/v1
+    kind: foobar
+    metadata:
+      name: whatever
+`)
+}
+
+func runKrmFunction(t *testing.T, input []byte, dir string) []byte {
+	cmd := exec.Command("go", "run", ".")
+	ib := bytes.NewReader(input)
+	cmd.Stdin = ib
+	ob := bytes.NewBuffer([]byte{})
+	cmd.Stdout = ob
+	eb := bytes.NewBuffer([]byte{})
+	cmd.Stderr = eb
+	cmd.Dir = dir
+	err := cmd.Run()
+	assert.NoErrorf(t, err, "Stdout:\n%s\nStderr:\n%s\n", ob.String(), eb.String())
+	return ob.Bytes()
+}
+
+func TestTransformerConverter(t *testing.T) {
+	dir := makeTempDir(t)
+	defer os.RemoveAll(dir)
+
+	ioutil.WriteFile(filepath.Join(dir, "Plugin.go"),
+		getTransformerCode(), 0644)
+
+	c := NewConverter(filepath.Join(dir, "output"),
+		filepath.Join(dir, "Plugin.go"))
+
+	err := c.Convert()
+	assert.NoError(t, err)
+
+	output := runKrmFunction(t, getTransformerInputResource(), filepath.Join(dir, "output"))
+	assert.Equal(t, `apiVersion: config.kubernetes.io/v1beta1
+kind: ResourceList
+items:
+- {"apiVersion": "apps/v1", "kind": "foobar", "metadata": {"name": "whatever", "namespace": "foo"}}
+functionConfig:
+  apiVersion: foo-corp.com/v1
+  kind: FulfillmentCenter
+  metadata:
+    name: staging
+    metadata:
+      annotations:
+        config.kubernetes.io/function: |
+          container:
+            image: gcr.io/example/foo:v1.0.0
+  namespace: foo
+  fieldSpecs:
+  - path: metadata/namespace
+    create: true
+`, string(output))
+}
+
+func getGeneratorCode() []byte {
+	return []byte(`package main
+
+import (
+	"sigs.k8s.io/kustomize/api/kv"
+	"sigs.k8s.io/kustomize/api/resmap"
+	"sigs.k8s.io/kustomize/api/types"
+	"sigs.k8s.io/yaml"
+)
+
+type plugin struct {
+	h                *resmap.PluginHelpers
+	types.ObjectMeta ` + "`json:\"metadata,omitempty\" yaml:\"metadata,omitempty\"`" + `
+	types.ConfigMapArgs
+}
+
+//noinspection GoUnusedGlobalVariable
+var KustomizePlugin plugin
+
+func (p *plugin) Config(h *resmap.PluginHelpers, config []byte) (err error) {
+	p.ConfigMapArgs = types.ConfigMapArgs{}
+	err = yaml.Unmarshal(config, p)
+	if p.ConfigMapArgs.Name == "" {
+		p.ConfigMapArgs.Name = p.Name
+	}
+	if p.ConfigMapArgs.Namespace == "" {
+		p.ConfigMapArgs.Namespace = p.Namespace
+	}
+	p.h = h
+	return
+}
+
+func (p *plugin) Generate() (resmap.ResMap, error) {
+	return p.h.ResmapFactory().FromConfigMapArgs(
+		kv.NewLoader(p.h.Loader(), p.h.Validator()), p.ConfigMapArgs)
+}`)
+}
+
+func getGeneratorInputResource() []byte {
+	return []byte(`
+apiVersion: config.kubernetes.io/v1beta1
+kind: ResourceList
+functionConfig:
+  apiVersion: foo-corp.com/v1
+  kind: FulfillmentCenter
+  metadata:
+    name: staging
+    metadata:
+      annotations:
+        config.kubernetes.io/function: |
+          container:
+            image: gcr.io/example/foo:v1.0.0
+items: []
+`)
+}
+
+func TestGeneratorConverter(t *testing.T) {
+	dir := makeTempDir(t)
+	defer os.RemoveAll(dir)
+
+	ioutil.WriteFile(filepath.Join(dir, "Plugin.go"),
+		getGeneratorCode(), 0644)
+
+	c := NewConverter(filepath.Join(dir, "output"),
+		filepath.Join(dir, "Plugin.go"))
+
+	err := c.Convert()
+	assert.NoError(t, err)
+	output := runKrmFunction(t, getGeneratorInputResource(), filepath.Join(dir, "output"))
+	assert.Equal(t, `apiVersion: config.kubernetes.io/v1beta1
+kind: ResourceList
+items:
+- {"apiVersion": "v1", "kind": "ConfigMap", "metadata": {"name": "staging"}}
+functionConfig:
+  apiVersion: foo-corp.com/v1
+  kind: FulfillmentCenter
+  metadata:
+    name: staging
+    metadata:
+      annotations:
+        config.kubernetes.io/function: |
+          container:
+            image: gcr.io/example/foo:v1.0.0
+`, string(output))
+}

cmd/pluginator/krmfunction/funcwrapper/statik.go

@@ -0,0 +1,14 @@
+// Code generated by statik. DO NOT EDIT.
+
+package funcwrapper
+
+import (
+	"github.com/rakyll/statik/fs"
+)
+
+
+func init() {
+	data := "PK\x03\x04\x14\x00\x08\x00\x08\x00K\xa7pQ\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\n\x00	\x00go.mod.srcUT\x05\x00\x01\xef\xe7\xb2_\x84\xce\xc1\xae\x820\x10\x85\xe15\xf3\x14]\xde\xbb`:3T\"\x0b}\x97\x82\x15\x1b\xa8EJI\xf4\xe9\x0dq\xe5B]\x9f/9\x7f\x88\xa7<:\x15\xac\xbf\x02\xf4Q1\xb2\x01\x98\xdd-\xfb\xd9\xa9?(z\xbf\\r\x8b]\x0c:Mg\xaet\x17\xdb\xd9\xaa\x95\x91\x90\xa0H\xbeO8\xec\x13\xfa\xa8\x87\x9c\x96\x18\xfc\xc3i;y\xb5\x12\xd6h>\x89\xe1n\xc3\xb8\x99\x06\xabw\xf3\x1a\x18\x05	\xfe\xb7\x94i\xb4\x9dS\xbf\x8e\xd4\xe1\xf8\xdd\x10R)$\xc4\xcc57\"\xc4\xa5\x95\x9d\x91\xc6\xba\xaa\x15\x03\xcf\x00\x00\x00\xff\xffPK\x07\x08\xb1\xe0\xcew\x9c\x00\x00\x00\n\x01\x00\x00PK\x03\x04\x14\x00\x08\x00\x08\x00C\xa7pQ\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x07\x00	\x00main.goUT\x05\x00\x01\xdf\xe7\xb2_\x94T\xcbn\xdb:\x10]\x93_1\xd7\x8b\x0b\xe9\xc2\x90pwA\x02\xaf\x82\xa4\x0d\xda\x04A\xea]\xd1\x05M\x8d\x1cB|\x08C\xaaN\x1a\xe8\xdf\x0b\xea\xe1H\xca\xa3\xe9\xc6\x80Gg\xce93\xc3\x99<\x87\xed\xbd\xf2P*\x8dpPZ\xc3\x0e\xa1&'\xd1{,@\xd8\x02\xd0\xec\xb0(\xb0\x80\xe0\xa0\xd6\xcd^Y\x11\x1ce\x9c\xd7BVb\x8fP6V\x1eH\xd45\x92'\xc9\xb92\xb5\xa3\x00	g\xab\xd2\x84\x15g+\xe7W\x9c\xb3\x95W{\x9fU'>S.\xaf\x1a\x1f\x9cQ\xbf0\x17\xb5\xca\xab\x13_`\xed\xf3\xaa\xb1>P#\xbb\xac\xb7\xe1\x84\xde\x88\xfa\x8f\x18\xd7\x90\xc4\xb7Q\xd5\xa30:/m^\x920xpT-\xb1\x11\xb0\xe2)\xe7yn\x9dV6\xf0X+\x18\xa1l\x92\xc2\x13g?\x05\x0d=\x81\xdeSv\xeel\xa9\xf6\x0d\x89\x9dF\xce\xfa\xe0\xa5\x90\xc1\xd1#\x9cn\xc0\xe2\xe1\x0e\xfd\xf51\x96\xa4\x9c\xb3\x9e\xe13\xea\xd8\xc1\x01u;\x8d%3\x9e\x982V\xf7U\xf9\x103\xfe=\xd6\x90\xddM>=\xb5\x9c3i\x8a\x08yF\x9c;c\x84-\x92)\xc9\xba\x1bc\x92\x02\x129\x8a\xb5E\x8dkQ\xafc$\xe6\xcf<d7\xc7B\xc8\x99\xbb\x1bW\xe07\xad$\xce8\xb3\xab\x80\xc6\xa7\x9c1Uv,\xffl\xc0*\xdd\x913\xc2\xd0\x90\x8da\xceX\xcb\xd9\xd0\x85\xbe\x7fG\xd1h*(7\x84\xb7\xeev\x02\x9ak]\xce\x90\x1f\x13\xe5\x8cE\xc4f\x98\xe10\xbcd6\x8f5L\x8d}\x8c\xb7\xc3\x845\xb8*\xd60\x90\x0fC\xcc\xb6$\xac/\x1d\x19\xa4\xbe\x9a\xf4,\x02;\x9e\xdeMx\xc6$\xfd\x10\xa2\xeck\xbas\xe1N\xb9\x05\xd4\x1eA\x95\xb0\x7f\xc3\xc0'\xb4Hq\x87_\xc8O'\xbe\x81\xfd\x88\xc4\xe4o\xf4y\xfft\x16\xaf`$\xed%\xb2\xad\x9b\xbc\x99\x8f6u\x08X\xa59kS>\xe6\x9cn@\x9a\"\xbbx@\xd9D\xafgK\xa6\xd2\x84\xec\x96\x94\x0d\xda&H\x14\xe5\x9c\xcf.\x1eTH\xfeO9ky\xbb\xdc\xf0\xf7\x17\x10\xfe\x1b:9.\xe410K\x8a\xda\x83\xe5\xe1\xf3\xcd\x92\xd6*\xbd\x86\xeeg\xb1\xe1-?\x1aY\xdc\x8b\xa5x\xaf\xd2\xb7{rh\xc6P\xd4\x1cs\x8f\xd75\x06\xbf\x8c\x7f\x1a\xc2b@\\\x99Z'i\xfa\x8a\xed\x91b\xa1\xd4\x99O_\xf6\xef\xdd\xb5-%(\x1b\x90J!\xf1\xa9M!\xf9\xfec\xf7\x18p\xdd\x9f\x9et\xd2\xb6x\x7f\xb3kA\xfe^\xe8\xa4\x94Q\xe8w\x00\x00\x00\xff\xffPK\x07\x08\x01S\xc7P\x7f\x02\x00\x00\xb1\x06\x00\x00PK\x01\x02\x14\x03\x14\x00\x08\x00\x08\x00K\xa7pQ\xb1\xe0\xcew\x9c\x00\x00\x00\n\x01\x00\x00\n\x00	\x00\x00\x00\x00\x00\x00\x00\x00\x00\xa0\x81\x00\x00\x00\x00go.mod.srcUT\x05\x00\x01\xef\xe7\xb2_PK\x01\x02\x14\x03\x14\x00\x08\x00\x08\x00C\xa7pQ\x01S\xc7P\x7f\x02\x00\x00\xb1\x06\x00\x00\x07\x00	\x00\x00\x00\x00\x00\x00\x00\x00\x00\xa0\x81\xdd\x00\x00\x00main.goUT\x05\x00\x01\xdf\xe7\xb2_PK\x05\x06\x00\x00\x00\x00\x02\x00\x02\x00\x7f\x00\x00\x00\x9a\x03\x00\x00\x00\x00"
+		fs.Register(data)
+	}
+	

cmd/pluginator/krmfunction/funcwrappersrc/fakeplugin.go

@@ -0,0 +1,20 @@
+//nolint
+package funcwrappersrc
+
+import (
+	"sigs.k8s.io/kustomize/api/resmap"
+)
+
+type plugin struct{}
+
+//noinspection GoUnusedGlobalVariable
+var KustomizePlugin plugin
+
+func (p *plugin) Config(
+	_ *resmap.PluginHelpers, _ []byte) (err error) {
+	return nil
+}
+
+func (p *plugin) Transform(_ resmap.ResMap) error {
+	return nil
+}

cmd/pluginator/krmfunction/funcwrappersrc/go.mod.src

@@ -0,0 +1,12 @@
+module main
+
+go 1.14
+
+require (
+	github.com/spf13/cobra v1.0.0
+	sigs.k8s.io/kustomize/api v0.6.4
+	sigs.k8s.io/kustomize/kyaml v0.9.3
+	sigs.k8s.io/yaml v1.2.0
+)
+
+replace sigs.k8s.io/kustomize/api v0.6.4 => sigs.k8s.io/kustomize/api v0.0.0-20201116192201-a25429ae3b24

cmd/pluginator/krmfunction/funcwrappersrc/main.go

@@ -0,0 +1,77 @@
+// This file will be processed and embedded to pluginator.
+
+package funcwrappersrc
+
+import (
+	"fmt"
+	"os"
+
+	"sigs.k8s.io/kustomize/api/k8sdeps/kunstruct"
+	"sigs.k8s.io/kustomize/api/resmap"
+	"sigs.k8s.io/kustomize/api/resource"
+	"sigs.k8s.io/kustomize/kyaml/fn/framework"
+	"sigs.k8s.io/yaml"
+)
+
+//nolint
+func main() {
+	var plugin resmap.Configurable
+	resmapFactory := newResMapFactory()
+
+	pluginHelpers := newPluginHelpers(resmapFactory)
+
+	resourceList := &framework.ResourceList{}
+
+	cmd := framework.Command(resourceList, func() error {
+		resMap, err := resmapFactory.NewResMapFromRNodeSlice(resourceList.Items)
+		if err != nil {
+			return err
+		}
+		pluginConfig, err := functionConfigToPluginConfig(resourceList.FunctionConfig)
+		if err != nil {
+			return err
+		}
+
+		err = plugin.Config(pluginHelpers, pluginConfig)
+		if err != nil {
+			return err
+		}
+		if t, ok := plugin.(resmap.TransformerPlugin); ok {
+			err = t.Transform(resMap)
+			if err != nil {
+				return err
+			}
+		} else if g, ok := plugin.(resmap.GeneratorPlugin); ok {
+			resMap, err = g.Generate()
+			if err != nil {
+				return err
+			}
+		}
+
+		resourceList.Items, err = resMap.ToRNodeSlice()
+		if err != nil {
+			return err
+		}
+		return nil
+	})
+	if err := cmd.Execute(); err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+}
+
+//nolint
+func newPluginHelpers(resmapFactory *resmap.Factory) *resmap.PluginHelpers {
+	return resmap.NewPluginHelpers(nil, nil, resmapFactory)
+}
+
+//nolint
+func newResMapFactory() *resmap.Factory {
+	resourceFactory := resource.NewFactory(kunstruct.NewKunstructuredFactoryImpl())
+	return resmap.NewFactory(resourceFactory, nil)
+}
+
+//nolint
+func functionConfigToPluginConfig(fc interface{}) ([]byte, error) {
+	return yaml.Marshal(fc)
+}