refactor: moves conversion to unstr to dedicated package (#1113)

We rely on conversion to Unstructured resources in quite a few places in the code base. With the introduction of a dedicated pkg, we can keep those functions together and reuse them across the code base.

> [!IMPORTANT]
> While converting Kustomize `ResMap` we do not use `MustYaml` func anymore, as this one panics. We attempt to convert to YAML and handle the error instead.

pkg/conversion/conversion.go

@@ -0,0 +1,52 @@
+package conversion
+
+import (
+	"regexp"
+	"strings"
+
+	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+	"sigs.k8s.io/kustomize/api/resmap"
+	"sigs.k8s.io/yaml"
+)
+
+const (
+	resourceSeparator = "(?m)^---[ \t]*$"
+)
+
+// StrToUnstructured converts a string containing multiple resources in YAML format to a slice of Unstructured objects.
+// The input string is split by "---" separator and each part is unmarshalled into an Unstructured object.
+func StrToUnstructured(resources string) ([]*unstructured.Unstructured, error) {
+	splitter := regexp.MustCompile(resourceSeparator)
+	objectStrings := splitter.Split(resources, -1)
+	objs := make([]*unstructured.Unstructured, 0, len(objectStrings))
+	for _, str := range objectStrings {
+		if strings.TrimSpace(str) == "" {
+			continue
+		}
+		u := &unstructured.Unstructured{}
+		if err := yaml.Unmarshal([]byte(str), u); err != nil {
+			return nil, err
+		}
+
+		objs = append(objs, u)
+	}
+	return objs, nil
+}
+
+// ResMapToUnstructured converts a ResMap to a slice of Unstructured objects.
+func ResMapToUnstructured(resMap resmap.ResMap) ([]*unstructured.Unstructured, error) {
+	resources := make([]*unstructured.Unstructured, 0, resMap.Size())
+	for _, res := range resMap.Resources() {
+		u := &unstructured.Unstructured{}
+		asYAML, errToYAML := res.AsYAML()
+		if errToYAML != nil {
+			return nil, errToYAML
+		}
+		if errUnmarshal := yaml.Unmarshal(asYAML, u); errUnmarshal != nil {
+			return nil, errUnmarshal
+		}
+		resources = append(resources, u)
+	}
+
+	return resources, nil
+}

pkg/deploy/deploy.go

@@ -38,14 +38,14 @@ import (
 	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
 	"k8s.io/apimachinery/pkg/runtime/schema"
 	"k8s.io/apimachinery/pkg/types"
-	"k8s.io/apimachinery/pkg/util/yaml"
 	ctrl "sigs.k8s.io/controller-runtime"
 	"sigs.k8s.io/controller-runtime/pkg/client"
 	"sigs.k8s.io/kustomize/api/krusty"
 	"sigs.k8s.io/kustomize/api/resmap"
 	"sigs.k8s.io/kustomize/kyaml/filesys"
 
 	"github.com/opendatahub-io/opendatahub-operator/v2/components"
+	"github.com/opendatahub-io/opendatahub-operator/v2/pkg/conversion"
 	"github.com/opendatahub-io/opendatahub-operator/v2/pkg/metadata/annotations"
 	"github.com/opendatahub-io/opendatahub-operator/v2/pkg/metadata/labels"
 	"github.com/opendatahub-io/opendatahub-operator/v2/pkg/plugins"
@@ -184,7 +184,7 @@ func DeployManifestsFromPath(
 		return fmt.Errorf("failed applying labels plugin when preparing Kustomize resources. %w", err)
 	}
 
-	objs, err := GetResources(resMap)
+	objs, err := conversion.ResMapToUnstructured(resMap)
 	if err != nil {
 		return err
 	}
@@ -199,20 +199,6 @@ func DeployManifestsFromPath(
 	return nil
 }
 
-func GetResources(resMap resmap.ResMap) ([]*unstructured.Unstructured, error) {
-	resources := make([]*unstructured.Unstructured, 0, resMap.Size())
-	for _, res := range resMap.Resources() {
-		u := &unstructured.Unstructured{}
-		err := yaml.Unmarshal([]byte(res.MustYaml()), u)
-		if err != nil {
-			return nil, err
-		}
-		resources = append(resources, u)
-	}
-
-	return resources, nil
-}
-
 func manageResource(ctx context.Context, cli client.Client, obj *unstructured.Unstructured, owner metav1.Object, applicationNamespace, componentName string, enabled bool) error {
 	// Return if resource is of Kind: Namespace and Name: odhApplicationsNamespace
 	if obj.GetKind() == "Namespace" && obj.GetName() == applicationNamespace {

pkg/feature/manifest.go

@@ -7,11 +7,11 @@ import (
 	"io"
 	"io/fs"
 	"path/filepath"
-	"regexp"
 	"strings"
 
-	"github.com/ghodss/yaml"
 	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+
+	"github.com/opendatahub-io/opendatahub-operator/v2/pkg/conversion"
 )
 
 type Manifest interface {
@@ -43,7 +43,7 @@ func (b *rawManifest) Process(_ any) ([]*unstructured.Unstructured, error) {
 	}
 	resources := string(content)
 
-	unstructuredObjs, convertErr := convertToUnstructuredSlice(resources)
+	unstructuredObjs, convertErr := conversion.StrToUnstructured(resources)
 	if convertErr != nil {
 		return nil, fmt.Errorf("failed to convert resources defined in %s to unstructured objects: %w", b.path, convertErr)
 	}
@@ -92,7 +92,7 @@ func (t *templateManifest) Process(data any) ([]*unstructured.Unstructured, erro
 
 	resources := buffer.String()
 
-	unstructuredObjs, convertErr := convertToUnstructuredSlice(resources)
+	unstructuredObjs, convertErr := conversion.StrToUnstructured(resources)
 	if convertErr != nil {
 		return nil, fmt.Errorf("failed to convert resources defined in %s to unstructured objects: %w", t.path, convertErr)
 	}
@@ -163,21 +163,3 @@ func CreateTemplateManifestFrom(fsys fs.FS, path string) *templateManifest {
 func isTemplateManifest(path string) bool {
 	return strings.Contains(filepath.Base(path), ".tmpl.")
 }
-
-func convertToUnstructuredSlice(resources string) ([]*unstructured.Unstructured, error) {
-	splitter := regexp.MustCompile(yamlResourceSeparator)
-	objectStrings := splitter.Split(resources, -1)
-	objs := make([]*unstructured.Unstructured, 0, len(objectStrings))
-	for _, str := range objectStrings {
-		if strings.TrimSpace(str) == "" {
-			continue
-		}
-		u := &unstructured.Unstructured{}
-		if err := yaml.Unmarshal([]byte(str), u); err != nil {
-			return nil, err
-		}
-
-		objs = append(objs, u)
-	}
-	return objs, nil
-}

pkg/feature/raw_resources.go

@@ -13,10 +13,6 @@ import (
 	"github.com/opendatahub-io/opendatahub-operator/v2/pkg/metadata/annotations"
 )
 
-const (
-	yamlResourceSeparator = "(?m)^---[ \t]*$"
-)
-
 func applyResources(ctx context.Context, cli client.Client, objects []*unstructured.Unstructured, metaOptions ...cluster.MetaOptions) error {
 	for _, source := range objects {
 		target := source.DeepCopy()