feat: lenient decoding of CNPG resources

This patch allows the barman-cloud plugin to work with operator being
structurally identical with CNPG but with a different API group.

It does that by using lenient decoding of the passed CNPG resources
and by injecting the detected GVK to the sidecar, that uses it to
properly encode and decode the Kubernetes resources.

Signed-off-by: Leonardo Cecchi <leonardo.cecchi@enterprisedb.com>

go.mod

@@ -136,3 +136,5 @@ require (
 	sigs.k8s.io/structured-merge-diff/v4 v4.5.0 // indirect
 	sigs.k8s.io/yaml v1.4.0 // indirect
 )
+
+replace github.com/cloudnative-pg/cnpg-i-machinery => github.com/leonardoce/cnpg-i-machinery v0.0.0-20250307135524-f7d0a34b5b3e

go.sum

@@ -26,8 +26,6 @@ github.com/cloudnative-pg/cloudnative-pg v1.25.1 h1:Yc6T7ikQ1AiWXBQht+6C3DoihrIp
 github.com/cloudnative-pg/cloudnative-pg v1.25.1/go.mod h1:96b9bRFLSr3uFWHjhytPdcvKIKwy9H6AG7cH0O6jefs=
 github.com/cloudnative-pg/cnpg-i v0.1.0 h1:QH2xTsrODMhEEc6B25GbOYe7ZIttDmSkYvXotfU5dfs=
 github.com/cloudnative-pg/cnpg-i v0.1.0/go.mod h1:G28BhgUEHqrxEyyQeHz8BbpMVAsGuLhJm/tHUbDi8Sw=
-github.com/cloudnative-pg/cnpg-i-machinery v0.1.2 h1:yY8tBkN8l8ENNWDMK0ZewK+nNzsxuSvxbSfkwJoSSZ0=
-github.com/cloudnative-pg/cnpg-i-machinery v0.1.2/go.mod h1:4Lf5Vfl8tvCsgs7H38+JMkvFhUMIDiNoZtzfwqyFE+E=
 github.com/cloudnative-pg/machinery v0.1.0 h1:tjRmsqQmsO/OlaT0uFmkEtVqgr+SGPM88cKZOHYKLBo=
 github.com/cloudnative-pg/machinery v0.1.0/go.mod h1:0V3vm44FaIsY+x4pm8ORry7xCC3AJiO+ebfPNxeP5Ck=
 github.com/cpuguy83/go-md2man/v2 v2.0.6/go.mod h1:oOW0eioCTA6cOiMLiUPZOpcVxMig6NIQQ7OS05n1F4g=
@@ -116,6 +114,8 @@ github.com/kubernetes-csi/external-snapshotter/client/v8 v8.2.0 h1:Q3jQ1NkFqv5o+
 github.com/kubernetes-csi/external-snapshotter/client/v8 v8.2.0/go.mod h1:E3vdYxHj2C2q6qo8/Da4g7P+IcwqRZyy3gJBzYybV9Y=
 github.com/kylelemons/godebug v1.1.0 h1:RPNrshWIDI6G2gRW9EHilWtl7Z6Sb1BR0xunSBf0SNc=
 github.com/kylelemons/godebug v1.1.0/go.mod h1:9/0rRGxNHcop5bhtWyNeEfOS8JIWk580+fNqagV/RAw=
+github.com/leonardoce/cnpg-i-machinery v0.0.0-20250307135524-f7d0a34b5b3e h1:j8lLGGMIvNqPKIWYAVUtz+OspxXwxK/s/jdg18ZuaGU=
+github.com/leonardoce/cnpg-i-machinery v0.0.0-20250307135524-f7d0a34b5b3e/go.mod h1:4Lf5Vfl8tvCsgs7H38+JMkvFhUMIDiNoZtzfwqyFE+E=
 github.com/lib/pq v1.10.9 h1:YXG7RB+JIjhP29X+OtkiDnYaXQwpS4JEWq7dtCCRUEw=
 github.com/lib/pq v1.10.9/go.mod h1:AlVN5x4E4T544tWzH6hKfbfQvm3HdbOxrmggDNAPY9o=
 github.com/magiconair/properties v1.8.7 h1:IeQXZAiQcpL9mgcAe1Nu6cX9LLw6ExEHKjN0VQdvPDY=

internal/cmd/instance/main.go

@@ -36,6 +36,8 @@ func NewCmd() *cobra.Command {
 	_ = viper.BindEnv("pod-name", "POD_NAME")
 	_ = viper.BindEnv("pgdata", "PGDATA")
 	_ = viper.BindEnv("spool-directory", "SPOOL_DIRECTORY")
+	_ = viper.BindEnv("custom-cnpg-group", "CUSTOM_CNPG_GROUP")
+	_ = viper.BindEnv("custom-cnpg-version", "CUSTOM_CNPG_VERSIONXS")
 
 	return cmd
 }

internal/cnpgi/instance/manager.go

@@ -8,26 +8,22 @@ import (
 	"github.com/spf13/viper"
 	corev1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/runtime/schema"
 	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
 	clientgoscheme "k8s.io/client-go/kubernetes/scheme"
 	ctrl "sigs.k8s.io/controller-runtime"
 	"sigs.k8s.io/controller-runtime/pkg/client"
 	"sigs.k8s.io/controller-runtime/pkg/log"
+	"sigs.k8s.io/controller-runtime/pkg/scheme"
 
 	barmancloudv1 "github.com/cloudnative-pg/plugin-barman-cloud/api/v1"
 	extendedclient "github.com/cloudnative-pg/plugin-barman-cloud/internal/cnpgi/instance/internal/client"
 )
 
-var scheme = runtime.NewScheme()
-
-func init() {
-	utilruntime.Must(barmancloudv1.AddToScheme(scheme))
-	utilruntime.Must(cnpgv1.AddToScheme(scheme))
-	utilruntime.Must(clientgoscheme.AddToScheme(scheme))
-}
-
 // Start starts the sidecar informers and CNPG-i server
 func Start(ctx context.Context) error {
+	scheme := generateScheme(ctx)
+
 	setupLog := log.FromContext(ctx)
 	setupLog.Info("Starting barman cloud instance plugin")
 	podName := viper.GetString("pod-name")
@@ -70,3 +66,35 @@ func Start(ctx context.Context) error {
 
 	return nil
 }
+
+// generateScheme creates a runtime.Scheme object with all the
+// definition needed to support the sidecar. This allows
+// the plugin to be used in every CNPG-based operator.
+func generateScheme(ctx context.Context) *runtime.Scheme {
+	result := runtime.NewScheme()
+
+	utilruntime.Must(barmancloudv1.AddToScheme(result))
+	utilruntime.Must(clientgoscheme.AddToScheme(result))
+
+	cnpgGroup := viper.GetString("custom-cnpg-group")
+	cnpgVersion := viper.GetString("custom-cnpg-version")
+	if len(cnpgGroup) == 0 {
+		cnpgGroup = cnpgv1.SchemeGroupVersion.Group
+	}
+	if len(cnpgVersion) == 0 {
+		cnpgVersion = cnpgv1.SchemeGroupVersion.Version
+	}
+
+	// Proceed with custom registration of the CNPG scheme
+	schemeGroupVersion := schema.GroupVersion{Group: cnpgGroup, Version: cnpgVersion}
+	schemeBuilder := &scheme.Builder{GroupVersion: schemeGroupVersion}
+	schemeBuilder.Register(&cnpgv1.Cluster{}, &cnpgv1.ClusterList{})
+	schemeBuilder.Register(&cnpgv1.Backup{}, &cnpgv1.BackupList{})
+	schemeBuilder.Register(&cnpgv1.ScheduledBackup{}, &cnpgv1.ScheduledBackupList{})
+	utilruntime.Must(schemeBuilder.AddToScheme(result))
+
+	schemeLog := log.FromContext(ctx)
+	schemeLog.Info("CNPG types registration", "schemeGroupVersion", schemeGroupVersion)
+
+	return result
+}

internal/cnpgi/operator/config/config.go

@@ -5,7 +5,6 @@ import (
 
 	cnpgv1 "github.com/cloudnative-pg/cloudnative-pg/api/v1"
 	"github.com/cloudnative-pg/cnpg-i-machinery/pkg/pluginhelper/decoder"
-	"k8s.io/apimachinery/pkg/runtime/schema"
 	"k8s.io/apimachinery/pkg/types"
 
 	"github.com/cloudnative-pg/plugin-barman-cloud/internal/cnpgi/metadata"
@@ -101,19 +100,11 @@ func (config *PluginConfiguration) GetReferredBarmanObjectsKey() []types.Namespa
 	return result
 }
 
-func getClusterGVK() schema.GroupVersionKind {
-	return schema.GroupVersionKind{
-		Group:   cnpgv1.SchemeGroupVersion.Group,
-		Version: cnpgv1.SchemeGroupVersion.Version,
-		Kind:    cnpgv1.ClusterKind,
-	}
-}
-
 // NewFromClusterJSON decodes a JSON representation of a cluster.
 func NewFromClusterJSON(clusterJSON []byte) (*PluginConfiguration, error) {
 	var result cnpgv1.Cluster
 
-	if err := decoder.DecodeObject(clusterJSON, &result, getClusterGVK()); err != nil {
+	if err := decoder.DecodeObjectLenient(clusterJSON, &result); err != nil {
 		return nil, err
 	}
 

internal/cnpgi/operator/lifecycle.go

@@ -4,9 +4,9 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"strings"
 
 	cnpgv1 "github.com/cloudnative-pg/cloudnative-pg/api/v1"
-	"github.com/cloudnative-pg/cloudnative-pg/pkg/utils"
 	"github.com/cloudnative-pg/cnpg-i-machinery/pkg/pluginhelper/decoder"
 	"github.com/cloudnative-pg/cnpg-i-machinery/pkg/pluginhelper/object"
 	"github.com/cloudnative-pg/cnpg-i/pkg/lifecycle"
@@ -77,10 +77,9 @@ func (impl LifecycleImplementation) LifecycleHook(
 	}
 
 	var cluster cnpgv1.Cluster
-	if err := decoder.DecodeObject(
+	if err := decoder.DecodeObjectLenient(
 		request.GetClusterDefinition(),
 		&cluster,
-		cnpgv1.SchemeGroupVersion.WithKind("Cluster"),
 	); err != nil {
 		return nil, err
 	}
@@ -138,7 +137,7 @@ func reconcileJob(
 	}
 
 	var job batchv1.Job
-	if err := decoder.DecodeObject(
+	if err := decoder.DecodeObjectStrict(
 		request.GetObjectDefinition(),
 		&job,
 		batchv1.SchemeGroupVersion.WithKind("Job"),
@@ -151,7 +150,7 @@ func reconcileJob(
 		WithValues("jobName", job.Name)
 	contextLogger.Debug("starting job reconciliation")
 
-	if job.Spec.Template.Labels[utils.JobRoleLabelName] != "full-recovery" {
+	if getCNPGJobRole(&job) != "full-recovery" {
 		contextLogger.Debug("job is not a recovery job, skipping")
 		return nil, nil
 	}
@@ -270,6 +269,14 @@ func reconcilePodSpec(
 			Name:  "SPOOL_DIRECTORY",
 			Value: "/controller/wal-restore-spool",
 		},
+		{
+			Name:  "CUSTOM_CNPG_GROUP",
+			Value: cluster.GetObjectKind().GroupVersionKind().Group,
+		},
+		{
+			Name:  "CUSTOM_CNPG_VERSION",
+			Value: cluster.GetObjectKind().GroupVersionKind().Version,
+		},
 	}
 
 	envs = append(envs, additionalEnvs...)
@@ -445,3 +452,15 @@ func volumeListHasVolume(volumes []corev1.Volume, name string) bool {
 
 	return false
 }
+
+// getCNPGJobRole gets the role associated to a CNPG job
+func getCNPGJobRole(job *batchv1.Job) string {
+	const jobRoleLabelSuffix = "/jobRole"
+	for k, v := range job.Spec.Template.Labels {
+		if strings.HasSuffix(k, jobRoleLabelSuffix) {
+			return v
+		}
+	}
+
+	return ""
+}

internal/cnpgi/operator/ownership.go

@@ -0,0 +1,39 @@
+package operator
+
+import (
+	"fmt"
+
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/utils/ptr"
+)
+
+// setOwnerReference explicitly set the owner reference between an
+// owner object and a controller one.
+//
+// Important: this function won't use any registered scheme and will
+// fail unless the metadata has been correctly set into the owner
+// object.
+func setOwnerReference(owner, controlled metav1.Object) error {
+	ro, ok := owner.(runtime.Object)
+	if !ok {
+		return fmt.Errorf("%T is not a runtime.Object, cannot call setOwnerReference", owner)
+	}
+
+	if len(ro.DeepCopyObject().GetObjectKind().GroupVersionKind().Group) == 0 {
+		return fmt.Errorf("%T metadata have not been set, cannot call setOwnerReference", owner)
+	}
+
+	controlled.SetOwnerReferences([]metav1.OwnerReference{
+		{
+			APIVersion:         ro.GetObjectKind().GroupVersionKind().GroupVersion().String(),
+			Kind:               ro.GetObjectKind().GroupVersionKind().Kind,
+			Name:               owner.GetName(),
+			UID:                owner.GetUID(),
+			BlockOwnerDeletion: ptr.To(true),
+			Controller:         ptr.To(true),
+		},
+	})
+
+	return nil
+}

internal/cnpgi/operator/reconciler.go

@@ -11,7 +11,6 @@ import (
 	rbacv1 "k8s.io/api/rbac/v1"
 	"k8s.io/apimachinery/pkg/api/equality"
 	apierrs "k8s.io/apimachinery/pkg/api/errors"
-	ctrl "sigs.k8s.io/controller-runtime"
 	"sigs.k8s.io/controller-runtime/pkg/client"
 
 	barmancloudv1 "github.com/cloudnative-pg/plugin-barman-cloud/api/v1"
@@ -61,10 +60,10 @@ func (r ReconcilerImplementation) Pre(
 
 	contextLogger.Debug("parsing cluster definition")
 	var cluster cnpgv1.Cluster
-	if err := decoder.DecodeObject(
+	if err := decoder.DecodeObjectLenient(
 		request.GetResourceDefinition(),
 		&cluster,
-		cnpgv1.SchemeGroupVersion.WithKind("Cluster")); err != nil {
+	); err != nil {
 		return nil, err
 	}
 
@@ -142,11 +141,7 @@ func (r ReconcilerImplementation) ensureRole(
 			"namespace", newRole.Namespace,
 		)
 
-		if err := ctrl.SetControllerReference(
-			cluster,
-			newRole,
-			r.Client.Scheme(),
-		); err != nil {
+		if err := setOwnerReference(cluster, newRole); err != nil {
 			return err
 		}
 
@@ -193,7 +188,7 @@ func (r ReconcilerImplementation) createRoleBinding(
 	cluster *cnpgv1.Cluster,
 ) error {
 	roleBinding := specs.BuildRoleBinding(cluster)
-	if err := ctrl.SetControllerReference(cluster, roleBinding, r.Client.Scheme()); err != nil {
+	if err := setOwnerReference(cluster, roleBinding); err != nil {
 		return err
 	}
 	return r.Client.Create(ctx, roleBinding)