Proper Deletion Behavior for Logical Backup PVCs

Logical backup PVCs are now properly identified when rmdata is run.
This ensures any PVCs for logical backups are properly preserved or
deleted depending on the specific settings specified when deleting a
cluster.  For instance, if '--keep-data' only is specified, then the
logical backups will now be deleted.  Additionally, if '--keep-backups'
is specified, then the logical backup PVCs will now be preserved.  This
is specifically accomplished by now matching on a prefix for the name
of any logical backup PVCs (prefix 'backup-<clusterName>-pgdump'),
instead of matching on the full name of the PVC (which includes the
name of the database name used for the logical backup, e.g.
'backup-<clusterName>-pgdump-<database>-pvc', and therefore could
vary).

Issue: [ch9381]

Author: andrewlecuyer

pgo-rmdata/rmdata/process.go

@@ -33,7 +33,7 @@ const (
 	MAX_TRIES            = 16
 	pgBackRestPathFormat = "/backrestrepo/%s"
 	pgBackRestRepoPVC    = "%s-pgbr-repo"
-	pgDumpPVC            = "backup-%s-pgdump-pvc"
+	pgDumpPVCPrefix      = "backup-%s-pgdump"
 	pgDataPathFormat     = "/pgdata/%s"
 	tablespacePathFormat = "/tablespaces/%s/%s"
 	// the tablespace on a replcia follows the pattern "<replicaName-tablespace-.."
@@ -477,7 +477,7 @@ func removePgtasks(request Request) {
 func getInstancePVCs(request Request) ([]string, error) {
 	pvcList := make([]string, 0)
 	selector := fmt.Sprintf("%s=%s", config.LABEL_PG_CLUSTER, request.ClusterName)
-	pgDump, pgBackRest := fmt.Sprintf(pgDumpPVC, request.ClusterName),
+	pgDump, pgBackRest := fmt.Sprintf(pgDumpPVCPrefix, request.ClusterName),
 		fmt.Sprintf(pgBackRestRepoPVC, request.ClusterName)
 
 	log.Debugf("instance pvcs overall selector: [%s]", selector)
@@ -505,7 +505,7 @@ func getInstancePVCs(request Request) ([]string, error) {
 
 		log.Debugf("found pvc: [%s]", pvcName)
 
-		if pvcName == pgDump || pvcName == pgBackRest {
+		if strings.HasPrefix(pvcName, pgDump) || pvcName == pgBackRest {
 			log.Debug("skipping...")
 			continue
 		}
@@ -658,14 +658,35 @@ func removeBackupJobs(request Request) {
 // "rm -rf" like in other commands). Well, we could...we could write a job to do
 // this, but that will be saved for future work
 func removeLogicalBackupPVCs(request Request) {
-	// get the name of the PVC, which uses a format that is fixed
-	pvcName := fmt.Sprintf(pgDumpPVC, request.ClusterName)
 
-	log.Debugf("remove pgdump pvc name [%s]", pvcName)
+	pvcList := make([]string, 0)
+	selector := fmt.Sprintf("%s=%s", config.LABEL_PG_CLUSTER, request.ClusterName)
+	dumpPrefix := fmt.Sprintf(pgDumpPVCPrefix, request.ClusterName)
+
+	// get all of the PVCs to analyze (see the step below)
+	pvcs, err := request.Clientset.
+		CoreV1().PersistentVolumeClaims(request.Namespace).
+		List(metav1.ListOptions{LabelSelector: selector})
+	if err != nil {
+		log.Error(err)
+		return
+	}
+
+	// Now iterate through all the PVCs to identify those that are for a logical backup and add
+	// them to the PVC list for deletion.  This pattern matching will be utilized until better
+	// labeling is in place to uniquely identify logical backup PVCs.
+	for _, pvc := range pvcs.Items {
+		pvcName := pvc.GetName()
+
+		if !strings.HasPrefix(pvcName, dumpPrefix) {
+			continue
+		}
+
+		pvcList = append(pvcList, pvcName)
+	}
+
+	log.Debugf("logical backup pvcs found: [%v]", pvcList)
 
-	// make a simple list of the PVCs that can be applied to the "removePVC"
-	// command
-	pvcList := []string{pvcName}
 	removePVCs(pvcList, request)
 }