fix: inject barman sidecar in replica clusters bootstrapped with pg_basebackup

hack/examples/cluster-replica-streaming.yaml

@@ -0,0 +1,36 @@
+apiVersion: postgresql.cnpg.io/v1
+kind: Cluster
+metadata:
+  name: cluster-replica
+spec:
+  instances: 3
+  bootstrap:
+    pg_basebackup:
+      source: source
+  replica:
+    enabled: true
+    source: source
+  externalClusters:
+  - name: source
+    connectionParameters:
+      host: cluster-example-rw.default.svc
+      user: streaming_replica
+      sslmode: verify-full
+      dbname: postgres
+    sslKey:
+      name: cluster-example-replication
+      key: tls.key
+    sslCert:
+      name: cluster-example-replication
+      key: tls.crt
+    sslRootCert:
+      name: cluster-example-ca
+      key: ca.crt
+    plugin:
+      name: barman-cloud.cloudnative-pg.io
+      parameters:
+        barmanObjectName: minio-store
+        serverName: cluster-example
+  storage:
+    size: 1Gi
+

internal/cnpgi/operator/config/config.go

@@ -263,7 +263,9 @@ func getReplicaSourcePlugin(cluster *cnpgv1.Cluster) *cnpgv1.PluginConfiguration
 func (config *PluginConfiguration) Validate() error {
 	err := NewConfigurationError()
 
-	if len(config.BarmanObjectName) == 0 && len(config.RecoveryBarmanObjectName) == 0 {
+	if len(config.BarmanObjectName) == 0 &&
+		len(config.RecoveryBarmanObjectName) == 0 &&
+		len(config.ReplicaSourceBarmanObjectName) == 0 {
 		return err.WithMessage("no reference to barmanObjectName have been included")
 	}
 

internal/cnpgi/operator/config/config_test.go

@@ -0,0 +1,126 @@
+/*
+Copyright © contributors to CloudNativePG, established as
+CloudNativePG a Series of LF Projects, LLC.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+
+SPDX-License-Identifier: Apache-2.0
+*/
+
+package config
+
+import (
+	cnpgv1 "github.com/cloudnative-pg/cloudnative-pg/api/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+
+	"github.com/cloudnative-pg/plugin-barman-cloud/internal/cnpgi/metadata"
+)
+
+var _ = Describe("PluginConfiguration.Validate", func() {
+	It("fails when no barman object name is set", func() {
+		cfg := &PluginConfiguration{}
+		Expect(cfg.Validate()).To(HaveOccurred())
+	})
+
+	It("passes when only BarmanObjectName is set (backup/archive)", func() {
+		cfg := &PluginConfiguration{BarmanObjectName: "my-store"}
+		Expect(cfg.Validate()).To(Succeed())
+	})
+
+	It("passes when only RecoveryBarmanObjectName is set (recovery bootstrap)", func() {
+		cfg := &PluginConfiguration{RecoveryBarmanObjectName: "my-store"}
+		Expect(cfg.Validate()).To(Succeed())
+	})
+
+	It("passes when only ReplicaSourceBarmanObjectName is set (pg_basebackup replica cluster)", func() {
+		cfg := &PluginConfiguration{ReplicaSourceBarmanObjectName: "my-store"}
+		Expect(cfg.Validate()).To(Succeed())
+	})
+})
+
+var _ = Describe("NewFromCluster", func() {
+	enabled := true
+
+	It("derives the replica source object store for a pg_basebackup replica cluster", func() {
+		cluster := &cnpgv1.Cluster{
+			ObjectMeta: metav1.ObjectMeta{Name: "cluster-replica", Namespace: "test-ns"},
+			Spec: cnpgv1.ClusterSpec{
+				Bootstrap: &cnpgv1.BootstrapConfiguration{
+					PgBaseBackup: &cnpgv1.BootstrapPgBaseBackup{Source: "source"},
+				},
+				ReplicaCluster: &cnpgv1.ReplicaClusterConfiguration{
+					Enabled: &enabled,
+					Source:  "source",
+				},
+				ExternalClusters: []cnpgv1.ExternalCluster{
+					{
+						Name: "source",
+						PluginConfiguration: &cnpgv1.PluginConfiguration{
+							Name: metadata.PluginName,
+							Parameters: map[string]string{
+								"barmanObjectName": "minio-store",
+								"serverName":       "cluster-example",
+							},
+						},
+					},
+				},
+			},
+		}
+
+		cfg := NewFromCluster(cluster)
+
+		// The replica source object store is derived from the external cluster plugin,
+		// while the backup/archive and recovery object stores remain empty: this is the
+		// distinguishing trait of a pg_basebackup replica cluster (a recovery-bootstrapped
+		// replica would also populate RecoveryBarmanObjectName).
+		Expect(cfg.ReplicaSourceBarmanObjectName).To(Equal("minio-store"))
+		Expect(cfg.ReplicaSourceServerName).To(Equal("cluster-example"))
+		Expect(cfg.BarmanObjectName).To(BeEmpty())
+		Expect(cfg.RecoveryBarmanObjectName).To(BeEmpty())
+
+		// Validate must accept it, otherwise the lifecycle hook skips sidecar injection.
+		Expect(cfg.Validate()).To(Succeed())
+	})
+
+	It("ignores a replica source backed by a different plugin", func() {
+		cluster := &cnpgv1.Cluster{
+			ObjectMeta: metav1.ObjectMeta{Name: "cluster-replica", Namespace: "test-ns"},
+			Spec: cnpgv1.ClusterSpec{
+				Bootstrap: &cnpgv1.BootstrapConfiguration{
+					PgBaseBackup: &cnpgv1.BootstrapPgBaseBackup{Source: "source"},
+				},
+				ReplicaCluster: &cnpgv1.ReplicaClusterConfiguration{
+					Enabled: &enabled,
+					Source:  "source",
+				},
+				ExternalClusters: []cnpgv1.ExternalCluster{
+					{
+						Name: "source",
+						PluginConfiguration: &cnpgv1.PluginConfiguration{
+							Name:       "some-other-plugin.cloudnative-pg.io",
+							Parameters: map[string]string{"barmanObjectName": "minio-store"},
+						},
+					},
+				},
+			},
+		}
+
+		cfg := NewFromCluster(cluster)
+
+		Expect(cfg.ReplicaSourceBarmanObjectName).To(BeEmpty())
+		Expect(cfg.Validate()).NotTo(Succeed())
+	})
+})

internal/cnpgi/operator/config/suite_test.go

@@ -0,0 +1,32 @@
+/*
+Copyright © contributors to CloudNativePG, established as
+CloudNativePG a Series of LF Projects, LLC.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+
+SPDX-License-Identifier: Apache-2.0
+*/
+
+package config
+
+import (
+	"testing"
+
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+)
+
+func TestConfig(t *testing.T) {
+	RegisterFailHandler(Fail)
+	RunSpecs(t, "Config Suite")
+}

internal/cnpgi/operator/lifecycle.go

@@ -273,8 +273,10 @@ func (impl LifecycleImplementation) collectAdditionalInstanceArgs(
 		return args
 	}
 
-	// Prefer the cluster object store (backup/archive). If not set, fallback to the recovery object store.
-	// If neither is configured, no additional args are provided.
+	// Only one object store provides the sidecar arguments, with precedence:
+	// BarmanObjectName (backup/archive) > RecoveryBarmanObjectName (recovery
+	// bootstrap) > ReplicaSourceBarmanObjectName (pg_basebackup replica).
+	// If none is configured, no additional args are provided.
 	if len(pluginConfiguration.BarmanObjectName) > 0 {
 		var barmanObjectStore barmancloudv1.ObjectStore
 		if err := impl.Client.Get(ctx, pluginConfiguration.GetBarmanObjectKey(), &barmanObjectStore); err != nil {
@@ -303,6 +305,20 @@ func (impl LifecycleImplementation) collectAdditionalInstanceArgs(
 		return args, nil
 	}
 
+	if len(pluginConfiguration.ReplicaSourceBarmanObjectName) > 0 {
+		key := pluginConfiguration.GetReplicaSourceBarmanObjectKey()
+		var barmanObjectStore barmancloudv1.ObjectStore
+		if err := impl.Client.Get(ctx, key, &barmanObjectStore); err != nil {
+			return nil, fmt.Errorf("while getting replica source barman object store %s: %w", key.String(), err)
+		}
+		args := barmanObjectStore.Spec.InstanceSidecarConfiguration.AdditionalContainerArgs
+		args = append(
+			args,
+			collectTypedAdditionalArgs(&barmanObjectStore)...,
+		)
+		return args, nil
+	}
+
 	return nil, nil
 }
 

internal/cnpgi/operator/lifecycle_resources.go

@@ -48,6 +48,9 @@ func (impl LifecycleImplementation) collectSidecarResourcesForPod(
 	ctx context.Context,
 	configuration *config.PluginConfiguration,
 ) (corev1.ResourceRequirements, error) {
+	// Only one object store provides the sidecar resources, with precedence:
+	// BarmanObjectName (backup/archive) > RecoveryBarmanObjectName (recovery
+	// bootstrap) > ReplicaSourceBarmanObjectName (pg_basebackup replica).
 	if len(configuration.BarmanObjectName) > 0 {
 		// On a replica cluster that also archives, the designated primary
 		// will use both the replica source object store and the object store
@@ -64,12 +67,25 @@ func (impl LifecycleImplementation) collectSidecarResourcesForPod(
 	}
 
 	if len(configuration.RecoveryBarmanObjectName) > 0 {
-		// On a replica cluster that doesn't archive, the designated primary
-		// uses only the replica source object store.
+		// On a cluster recovering from an object store (including log-shipping
+		// replica clusters, where the recovery and replica source object stores
+		// coincide), we use the recovery object store for configuring the
+		// resources of the sidecar container.
+		var barmanObjectStore barmancloudv1.ObjectStore
+		if err := impl.Client.Get(ctx, configuration.GetRecoveryBarmanObjectKey(), &barmanObjectStore); err != nil {
+			return corev1.ResourceRequirements{}, err
+		}
+
+		return barmanObjectStore.Spec.InstanceSidecarConfiguration.Resources, nil
+	}
+
+	if len(configuration.ReplicaSourceBarmanObjectName) > 0 {
+		// On a replica cluster bootstrapped via pg_basebackup, the designated
+		// primary uses only the replica source object store.
 		// In this case, we use the replica source object store for configuring
 		// the resources of the sidecar container.
 		var barmanObjectStore barmancloudv1.ObjectStore
-		if err := impl.Client.Get(ctx, configuration.GetRecoveryBarmanObjectKey(), &barmanObjectStore); err != nil {
+		if err := impl.Client.Get(ctx, configuration.GetReplicaSourceBarmanObjectKey(), &barmanObjectStore); err != nil {
 			return corev1.ResourceRequirements{}, err
 		}