feat: add utility functions to determine resource and storage versions

Author: exdx

pkg/lib/crd/version.go

@@ -2,10 +2,14 @@ package crd
 
 import (
 	"fmt"
+	"k8s.io/apimachinery/pkg/runtime"
 	"strings"
 
 	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
 	"k8s.io/apimachinery/pkg/util/yaml"
+
+	apiextensionsv1 "k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/v1"
+	apiextensionsv1beta1 "k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/v1beta1"
 )
 
 // V1Beta1 refers to the deprecated v1beta1 APIVersion of CRD objects
@@ -39,3 +43,56 @@ func Version(manifest *string) (string, error) {
 	return v, nil
 }
 
+// Versions returns all resource versions present in the CRD. Compatible with both v1beta1 and v1 CRDs.
+func ResourceVersions(obj runtime.Object) (map[string]struct{}, error) {
+	versions := make(map[string]struct{})
+
+	switch crd := obj.(type) {
+	case *apiextensionsv1.CustomResourceDefinition:
+		for _, version := range crd.Spec.Versions {
+			versions[version.Name] = struct{}{}
+		}
+		return versions, nil
+	case *apiextensionsv1beta1.CustomResourceDefinition:
+		for _, version := range crd.Spec.Versions {
+			versions[version.Name] = struct{}{}
+		}
+		if crd.Spec.Version != "" {
+			versions[crd.Spec.Version] = struct{}{}
+		}
+		return versions, nil
+	default:
+		return nil, fmt.Errorf("could not find all versions present in CRD")
+	}
+}
+
+func StoredVersions(obj runtime.Object) []string {
+	switch crd := obj.(type) {
+	case *apiextensionsv1.CustomResourceDefinition:
+		return crd.Status.StoredVersions
+	case *apiextensionsv1beta1.CustomResourceDefinition:
+		return crd.Status.StoredVersions
+	}
+	return nil
+}
+
+// NewStoredVersions returns all the versions that are stored in both the new and old CRD.
+// If some versions are no longer stored in the new CRD then OLM must migrate existing CRs at the old storage version.
+func NewStoredVersions(oldCRD runtime.Object, newCRD runtime.Object) ([]string, error) {
+	var newStoredVersions []string
+
+	newCRDVersions, err := ResourceVersions(newCRD)
+	if err != nil {
+		return nil, err
+	}
+
+	for _, v := range StoredVersions(oldCRD) {
+		_, ok := newCRDVersions[v]
+		if ok {
+			newStoredVersions = append(newStoredVersions, v)
+		}
+	}
+
+	return newStoredVersions, nil
+}
+