fix: use kyaml to preserve kustomization (#274)

* fix: use kyaml to preserve kustomization

fixes #250
fixes #268
fixes #247

* chore: linter error

* fix: tests and linting

* go mod tidy

3 files changed, 137 insertions, 31 deletions

diff --git a/pkg/argocd/git.go b/pkg/argocd/git.go
index 7a52421..c191a31 100644
--- a/pkg/argocd/git.go
+++ b/pkg/argocd/git.go
@@ -9,9 +9,9 @@ import (
 	"path/filepath"
 	"text/template"
 
-	"sigs.k8s.io/kustomize/pkg/commands/kustfile"
-	"sigs.k8s.io/kustomize/pkg/fs"
-	image2 "sigs.k8s.io/kustomize/pkg/image"
+	"sigs.k8s.io/kustomize/api/konfig"
+	"sigs.k8s.io/kustomize/api/types"
+	kyaml "sigs.k8s.io/kustomize/kyaml/yaml"
 
 	"github.com/argoproj-labs/argocd-image-updater/pkg/image"
 
@@ -221,36 +221,71 @@ func writeKustomization(app *v1alpha1.Application, wbc *WriteBackConfig, gitC gi
 
 	log.Infof("updating base %s", base)
 
-	kf, err := kustfile.NewKustomizationFile(fs.MakeRealFS())
+	kustFile := findKustomization(base)
+	if kustFile == "" {
+		return fmt.Errorf("could not find kustomization in %s", base), false
+	}
+
+	filterFunc, err := imagesFilter(app.Spec.Source.Kustomize.Images)
 	if err != nil {
-		return
+		return err, false
 	}
-	kustomization, err := kf.Read()
+	err = kyaml.UpdateFile(filterFunc, kustFile)
 	if err != nil {
-		return
+		return err, false
 	}
 
-Images:
-	for _, img := range app.Spec.Source.Kustomize.Images {
-		override := parseImageOverride(img)
-		for i, imgSet := range kustomization.Images {
-			if imgSet.Name == override.Name {
-				kustomization.Images[i] = override
-				continue Images
-			}
+	return nil, false
+}
+
+func imagesFilter(images v1alpha1.KustomizeImages) (kyaml.Filter, error) {
+	var overrides []kyaml.Filter
+	for _, img := range images {
+		override, err := imageFilter(parseImageOverride(img))
+		if err != nil {
+			return nil, err
 		}
-		// wasn't an existing override, add one
-		kustomization.Images = append(kustomization.Images, override)
+		overrides = append(overrides, override)
 	}
 
-	if err := kf.Write(kustomization); err != nil {
-		return err, false
+	return kyaml.FilterFunc(func(object *kyaml.RNode) (*kyaml.RNode, error) {
+		err := object.PipeE(append([]kyaml.Filter{kyaml.LookupCreate(
+			kyaml.SequenceNode, "images",
+		)}, overrides...)...)
+		return object, err
+	}), nil
+}
+
+func imageFilter(imgSet types.Image) (kyaml.Filter, error) {
+	data, err := kyaml.Marshal(imgSet)
+	if err != nil {
+		return nil, err
+	}
+	update, err := kyaml.Parse(string(data))
+	if err != nil {
+		return nil, err
 	}
+	setter := kyaml.ElementSetter{
+		Element: update.YNode(),
+		Keys:    []string{"name"},
+		Values:  []string{imgSet.Name},
+	}
+	return kyaml.FilterFunc(func(object *kyaml.RNode) (*kyaml.RNode, error) {
+		return object, object.PipeE(setter)
+	}), nil
+}
 
-	return
+func findKustomization(base string) string {
+	for _, f := range konfig.RecognizedKustomizationFileNames() {
+		kustFile := path.Join(base, f)
+		if stat, err := os.Stat(kustFile); err == nil && !stat.IsDir() {
+			return kustFile
+		}
+	}
+	return ""
 }
 
-func parseImageOverride(str v1alpha1.KustomizeImage) image2.Image {
+func parseImageOverride(str v1alpha1.KustomizeImage) types.Image {
 	// TODO is this a valid use? format could diverge
 	img := image.NewFromIdentifier(string(str))
 	tagName := ""
@@ -267,7 +302,7 @@ func parseImageOverride(str v1alpha1.KustomizeImage) image2.Image {
 		img.ImageAlias = img.ImageName
 		img.ImageName = "" // inside baseball (see return): name isn't changing, just tag, so don't write newName
 	}
-	return image2.Image{
+	return types.Image{
 		Name:    img.ImageAlias,
 		NewName: img.ImageName,
 		NewTag:  tagName,
diff --git a/pkg/argocd/git_test.go b/pkg/argocd/git_test.go
index 5a60d57..92731d5 100644
--- a/pkg/argocd/git_test.go
+++ b/pkg/argocd/git_test.go
@@ -9,9 +9,11 @@ import (
 	"github.com/argoproj-labs/argocd-image-updater/pkg/image"
 	"github.com/argoproj-labs/argocd-image-updater/pkg/tag"
 
+	"sigs.k8s.io/kustomize/api/types"
+	kyaml "sigs.k8s.io/kustomize/kyaml/yaml"
+
 	"github.com/argoproj/argo-cd/v2/pkg/apis/application/v1alpha1"
 	"github.com/stretchr/testify/assert"
-	image2 "sigs.k8s.io/kustomize/pkg/image"
 )
 
 func Test_TemplateCommitMessage(t *testing.T) {
@@ -44,36 +46,36 @@ func Test_parseImageOverride(t *testing.T) {
 	cases := []struct {
 		name     string
 		override v1alpha1.KustomizeImage
-		expected image2.Image
+		expected types.Image
 	}{
-		{"tag update", "ghcr.io:1234/foo/foo:123", image2.Image{
+		{"tag update", "ghcr.io:1234/foo/foo:123", types.Image{
 			Name:   "ghcr.io:1234/foo/foo",
 			NewTag: "123",
 		}},
-		{"image update", "ghcr.io:1234/foo/foo=ghcr.io:1234/bar", image2.Image{
+		{"image update", "ghcr.io:1234/foo/foo=ghcr.io:1234/bar", types.Image{
 			Name:    "ghcr.io:1234/foo/foo",
 			NewName: "ghcr.io:1234/bar",
 		}},
-		{"update everything", "ghcr.io:1234/foo/foo=1234.foo.com:9876/bar:123", image2.Image{
+		{"update everything", "ghcr.io:1234/foo/foo=1234.foo.com:9876/bar:123", types.Image{
 			Name:    "ghcr.io:1234/foo/foo",
 			NewName: "1234.foo.com:9876/bar",
 			NewTag:  "123",
 		}},
-		{"change registry and tag", "ghcr.io:1234/foo/foo=1234.dkr.ecr.us-east-1.amazonaws.com/bar:123", image2.Image{
+		{"change registry and tag", "ghcr.io:1234/foo/foo=1234.dkr.ecr.us-east-1.amazonaws.com/bar:123", types.Image{
 			Name:    "ghcr.io:1234/foo/foo",
 			NewName: "1234.dkr.ecr.us-east-1.amazonaws.com/bar",
 			NewTag:  "123",
 		}},
-		{"change only registry", "0001.dkr.ecr.us-east-1.amazonaws.com/bar=1234.dkr.ecr.us-east-1.amazonaws.com/bar", image2.Image{
+		{"change only registry", "0001.dkr.ecr.us-east-1.amazonaws.com/bar=1234.dkr.ecr.us-east-1.amazonaws.com/bar", types.Image{
 			Name:    "0001.dkr.ecr.us-east-1.amazonaws.com/bar",
 			NewName: "1234.dkr.ecr.us-east-1.amazonaws.com/bar",
 		}},
-		{"change image and set digest", "foo=acme/app@sha256:e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855", image2.Image{
+		{"change image and set digest", "foo=acme/app@sha256:e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855", types.Image{
 			Name:    "foo",
 			NewName: "acme/app",
 			Digest:  "sha256:e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855",
 		}},
-		{"set digest", "acme/app@sha256:e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855", image2.Image{
+		{"set digest", "acme/app@sha256:e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855", types.Image{
 			Name:   "acme/app",
 			Digest: "sha256:e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855",
 		}},
@@ -86,3 +88,66 @@ func Test_parseImageOverride(t *testing.T) {
 	}
 
 }
+
+func Test_imagesFilter(t *testing.T) {
+	for _, tt := range []struct {
+		name     string
+		images   v1alpha1.KustomizeImages
+		expected string
+	}{
+		{name: "simple", images: v1alpha1.KustomizeImages{"foo"}, expected: `
+images:
+- name: foo
+`},
+		{name: "tagged", images: v1alpha1.KustomizeImages{"foo:bar"}, expected: `
+images:
+- name: foo
+  newTag: bar
+`},
+		{name: "rename", images: v1alpha1.KustomizeImages{"baz=foo:bar"}, expected: `
+images:
+- name: baz
+  newName: foo
+  newTag: bar
+`},
+		{name: "digest", images: v1alpha1.KustomizeImages{"baz=foo@sha12345"}, expected: `
+images:
+- name: baz
+  newName: foo
+  digest: sha12345
+`},
+		{name: "digest simple", images: v1alpha1.KustomizeImages{"foo@sha12345"}, expected: `
+images:
+- name: foo
+  digest: sha12345
+`},
+		{name: "all", images: v1alpha1.KustomizeImages{
+			"foo",
+			"foo=bar", // merges with above
+			"baz@sha12345",
+			"bar:123",
+			"foo=bar:123", // merges and overwrites the first two
+		}, expected: `
+images:
+- name: foo
+  newName: bar
+  newTag: "123"
+- name: baz
+  digest: sha12345
+- name: bar
+  newTag: "123"
+`},
+	} {
+		t.Run(tt.name, func(t *testing.T) {
+			filter, err := imagesFilter(tt.images)
+			assert.NoError(t, err)
+
+			node := kyaml.NewRNode(&kyaml.Node{Kind: kyaml.DocumentNode, Content: []*kyaml.Node{
+				kyaml.NewMapRNode(nil).YNode(),
+			}})
+			node, err = filter.Filter(node)
+			assert.NoError(t, err)
+			assert.YAMLEq(t, tt.expected, node.MustString())
+		})
+	}
+}
diff --git a/pkg/argocd/update_test.go b/pkg/argocd/update_test.go
index 5b94b31..8ae9b2c 100644
--- a/pkg/argocd/update_test.go
+++ b/pkg/argocd/update_test.go
@@ -1737,6 +1737,8 @@ func Test_CommitUpdates(t *testing.T) {
 		assert.NoError(t, ioutil.WriteFile(kf, []byte(`
 kind: Kustomization
 apiVersion: kustomize.config.k8s.io/v1beta1
+
+replacements: []
 `), os.ModePerm))
 
 		gitMock.On("Checkout", mock.Anything).Run(func(args mock.Arguments) {
@@ -1765,6 +1767,8 @@ images:
   - name: bar
     newName: baz
     newTag: "123"
+
+replacements: []
 `, string(kust))
 
 		// test the merge case too
@@ -1781,6 +1785,8 @@ images:
     newTag: "123"
   - name: bar
     newName: qux
+
+replacements: []
 `, string(kust))
 	})