fix: duplicate certificate projections (#331)

When referring to the same ObjectStore with custom TLS certificates
multiple times, the plugin was adding the same volume projection two
times. This lead to a wrong Job definition.

This patch makes the plugin add a sidecar to replica cluster Pods that
are using the plugin to get WALs, even if the plugin itself is not used
for WAL archiving.

Closes: #329

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

hack/examples/cluster-replica-log-shipping.yaml

@@ -0,0 +1,22 @@
+apiVersion: postgresql.cnpg.io/v1
+kind: Cluster
+metadata:
+  name: cluster-replica
+spec:
+  instances: 3
+  bootstrap:
+    recovery:
+      source: source
+  replica:
+    enabled: true
+    source: source
+  externalClusters:
+  - name: source
+    plugin:
+      name: barman-cloud.cloudnative-pg.io
+      parameters:
+        barmanObjectName: minio-store
+        serverName: cluster-example
+  storage:
+    size: 1Gi
+

internal/cnpgi/operator/config/config.go

@@ -5,6 +5,7 @@ import (
 
 	cnpgv1 "github.com/cloudnative-pg/cloudnative-pg/api/v1"
 	"github.com/cloudnative-pg/cnpg-i-machinery/pkg/pluginhelper/decoder"
+	"github.com/cloudnative-pg/machinery/pkg/stringset"
 	"k8s.io/apimachinery/pkg/types"
 
 	"github.com/cloudnative-pg/plugin-barman-cloud/internal/cnpgi/metadata"
@@ -85,16 +86,23 @@ func (config *PluginConfiguration) GetReplicaSourceBarmanObjectKey() types.Names
 // GetReferredBarmanObjectsKey gets the list of barman objects referred by this
 // plugin configuration
 func (config *PluginConfiguration) GetReferredBarmanObjectsKey() []types.NamespacedName {
-	result := make([]types.NamespacedName, 0, 3)
-
+	objectNames := stringset.New()
 	if len(config.BarmanObjectName) > 0 {
-		result = append(result, config.GetBarmanObjectKey())
+		objectNames.Put(config.BarmanObjectName)
 	}
 	if len(config.RecoveryBarmanObjectName) > 0 {
-		result = append(result, config.GetRecoveryBarmanObjectKey())
+		objectNames.Put(config.RecoveryBarmanObjectName)
 	}
 	if len(config.ReplicaSourceBarmanObjectName) > 0 {
-		result = append(result, config.GetReplicaSourceBarmanObjectKey())
+		objectNames.Put(config.ReplicaSourceBarmanObjectName)
+	}
+
+	result := make([]types.NamespacedName, 0, 3)
+	for _, name := range objectNames.ToSortedList() {
+		result = append(result, types.NamespacedName{
+			Name:      name,
+			Namespace: config.Cluster.Namespace,
+		})
 	}
 
 	return result

internal/cnpgi/operator/lifecycle.go

@@ -118,7 +118,7 @@ func (impl LifecycleImplementation) reconcileJob(
 		return nil, err
 	}
 
-	certificates, err := impl.collectAdditionalCertificates(ctx, cluster.Namespace, pluginConfiguration)
+	certificates, err := impl.collectAdditionalCertificates(ctx, pluginConfiguration)
 	if err != nil {
 		return nil, err
 	}
@@ -197,7 +197,7 @@ func (impl LifecycleImplementation) reconcilePod(
 		return nil, err
 	}
 
-	certificates, err := impl.collectAdditionalCertificates(ctx, cluster.Namespace, pluginConfiguration)
+	certificates, err := impl.collectAdditionalCertificates(ctx, pluginConfiguration)
 	if err != nil {
 		return nil, err
 	}
@@ -223,7 +223,8 @@ func reconcilePod(
 
 	mutatedPod := pod.DeepCopy()
 
-	if len(pluginConfiguration.BarmanObjectName) != 0 {
+	if len(pluginConfiguration.BarmanObjectName) != 0 ||
+		len(pluginConfiguration.ReplicaSourceBarmanObjectName) != 0 {
 		if err := reconcilePodSpec(
 			cluster,
 			&mutatedPod.Spec,

internal/cnpgi/operator/lifecycle_certificates.go

@@ -18,38 +18,16 @@ const barmanCertificatesVolumeName = "barman-certificates"
 
 func (impl LifecycleImplementation) collectAdditionalCertificates(
 	ctx context.Context,
-	namespace string,
 	pluginConfiguration *config.PluginConfiguration,
 ) ([]corev1.VolumeProjection, error) {
 	var result []corev1.VolumeProjection
 
-	if len(pluginConfiguration.BarmanObjectName) > 0 {
-		envs, err := impl.collectObjectStoreCertificates(
-			ctx,
-			types.NamespacedName{
-				Name:      pluginConfiguration.BarmanObjectName,
-				Namespace: namespace,
-			},
-		)
+	for _, barmanObjectKey := range pluginConfiguration.GetReferredBarmanObjectsKey() {
+		certs, err := impl.collectObjectStoreCertificates(ctx, barmanObjectKey)
 		if err != nil {
 			return nil, err
 		}
-		result = append(result, envs...)
-	}
-
-	if len(pluginConfiguration.RecoveryBarmanObjectName) > 0 &&
-		pluginConfiguration.RecoveryBarmanObjectName != pluginConfiguration.BarmanObjectName {
-		envs, err := impl.collectObjectStoreCertificates(
-			ctx,
-			types.NamespacedName{
-				Name:      pluginConfiguration.RecoveryBarmanObjectName,
-				Namespace: namespace,
-			},
-		)
-		if err != nil {
-			return nil, err
-		}
-		result = append(result, envs...)
+		result = append(result, certs...)
 	}
 
 	return result, nil