fix: inject barman sidecar in replica clusters bootstrapped with pg_basebackup

Replica clusters that use `pg_basebackup` as the bootstrap method and stream
WAL from an object store were not getting the barman sidecar injected, causing
WAL restore to fail silently. These clusters are now handled correctly.

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

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 +1,47 @@
+/*
+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 (
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+)
+
+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())
+	})
+})

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")
+}