cli: helm install and upgrade unification (#2244)

cli/internal/kubecmd/backup.go

@@ -0,0 +1,115 @@
+/*
+Copyright (c) Edgeless Systems GmbH
+
+SPDX-License-Identifier: AGPL-3.0-only
+*/
+
+package kubecmd
+
+import (
+	"context"
+	"fmt"
+	"path/filepath"
+
+	apiextensionsv1 "k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/v1"
+	k8serrors "k8s.io/apimachinery/pkg/api/errors"
+	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"sigs.k8s.io/yaml"
+)
+
+type crdLister interface {
+	ListCRDs(ctx context.Context) ([]apiextensionsv1.CustomResourceDefinition, error)
+	ListCRs(ctx context.Context, gvr schema.GroupVersionResource) ([]unstructured.Unstructured, error)
+}
+
+// BackupCRDs backs up all CRDs to the upgrade workspace.
+func (k *KubeCmd) BackupCRDs(ctx context.Context, upgradeDir string) ([]apiextensionsv1.CustomResourceDefinition, error) {
+	k.log.Debugf("Starting CRD backup")
+	crds, err := k.kubectl.ListCRDs(ctx)
+	if err != nil {
+		return nil, fmt.Errorf("getting CRDs: %w", err)
+	}
+
+	crdBackupFolder := k.crdBackupFolder(upgradeDir)
+	if err := k.fileHandler.MkdirAll(crdBackupFolder); err != nil {
+		return nil, fmt.Errorf("creating backup dir: %w", err)
+	}
+	for i := range crds {
+		path := filepath.Join(crdBackupFolder, crds[i].Name+".yaml")
+
+		k.log.Debugf("Creating CRD backup: %s", path)
+
+		// We have to manually set kind/apiversion because of a long-standing limitation of the API:
+		// https://github.com/kubernetes/kubernetes/issues/3030#issuecomment-67543738
+		// The comment states that kind/version are encoded in the type.
+		// The package holding the CRD type encodes the version.
+		crds[i].Kind = "CustomResourceDefinition"
+		crds[i].APIVersion = "apiextensions.k8s.io/v1"
+
+		yamlBytes, err := yaml.Marshal(crds[i])
+		if err != nil {
+			return nil, err
+		}
+		if err := k.fileHandler.Write(path, yamlBytes); err != nil {
+			return nil, err
+		}
+	}
+	k.log.Debugf("CRD backup complete")
+	return crds, nil
+}
+
+// BackupCRs backs up all CRs to the upgrade workspace.
+func (k *KubeCmd) BackupCRs(ctx context.Context, crds []apiextensionsv1.CustomResourceDefinition, upgradeDir string) error {
+	k.log.Debugf("Starting CR backup")
+	for _, crd := range crds {
+		k.log.Debugf("Creating backup for resource type: %s", crd.Name)
+
+		// Iterate over all versions of the CRD
+		// TODO: Consider iterating over crd.Status.StoredVersions instead
+		// Currently, we have to ignore not-found errors, because a CRD might define
+		// a version that is not installed in the cluster.
+		// With the StoredVersions field, we could only iterate over the installed versions.
+		for _, version := range crd.Spec.Versions {
+			k.log.Debugf("Creating backup of CRs for %q at version %q", crd.Name, version.Name)
+
+			gvr := schema.GroupVersionResource{Group: crd.Spec.Group, Version: version.Name, Resource: crd.Spec.Names.Plural}
+			crs, err := k.kubectl.ListCRs(ctx, gvr)
+			if err != nil {
+				if !k8serrors.IsNotFound(err) {
+					return fmt.Errorf("retrieving CR %s: %w", crd.Name, err)
+				}
+				k.log.Debugf("No CRs found for %q at version %q, skipping...", crd.Name, version.Name)
+				continue
+			}
+
+			backupFolder := k.backupFolder(upgradeDir)
+			for _, cr := range crs {
+				targetFolder := filepath.Join(backupFolder, gvr.Group, gvr.Version, cr.GetNamespace(), cr.GetKind())
+				if err := k.fileHandler.MkdirAll(targetFolder); err != nil {
+					return fmt.Errorf("creating resource dir: %w", err)
+				}
+				path := filepath.Join(targetFolder, cr.GetName()+".yaml")
+				yamlBytes, err := yaml.Marshal(cr.Object)
+				if err != nil {
+					return err
+				}
+				if err := k.fileHandler.Write(path, yamlBytes); err != nil {
+					return err
+				}
+			}
+		}
+
+		k.log.Debugf("Backup for resource type %q complete", crd.Name)
+	}
+	k.log.Debugf("CR backup complete")
+	return nil
+}
+
+func (k *KubeCmd) backupFolder(upgradeDir string) string {
+	return filepath.Join(upgradeDir, "backups")
+}
+
+func (k *KubeCmd) crdBackupFolder(upgradeDir string) string {
+	return filepath.Join(k.backupFolder(upgradeDir), "crds")
+}