add cleanup for backups

lxc-backup.sh

@@ -1,7 +1,7 @@
 #!/usr/bin/env bash
 
 main() {
-  while getopts ":l:d:t:" opt; do
+  while getopts ":l:d:t:c:h" opt; do
     case "${opt}" in
       l)
         unset VM_FILTER
@@ -14,6 +14,10 @@ main() {
       t)
         declare -g TARGET="$OPTARG"
         ;;
+      c)
+        declare -g run_cleanup=y
+        declare -g files_to_keep="${OPTARG}"
+        ;;
       h)
         usage
         ;;
@@ -43,12 +47,13 @@ list_vms() {
 
 usage() {
   cat <<EOF
-Usage: ${0##*/} [-l vm[,vm...]] [-d backup_dir] [-t lxc|incus] [-h]
+Usage: ${0##*/} [-l vm[,vm...]] [-d backup_dir] [-t lxc|incus] [-c <keep n backups>] [-h]
 
 Options:
   -l  Comma-separated list of VMs to back up
   -d  Directory where backups will be stored (default: current directory)
   -t  Manager type: lxc or incus (default: lxc)
+  -c  Cleanup old backups keeping a set number (default: 2)
   -h  Show this message
 
 EOF
@@ -80,7 +85,22 @@ start_backup() {
   [[ -d "$destination" ]] || mkdir "$destination"
   [[ -f "${destination}/${backup_name}" ]] && { echo "Backup already exists"; return 2; }
 
-  lxc export "$vm" "${destination}/${backup_name}"
+  lxc export "$vm" "${destination}/${backup_name}" || { echo "Error exporting $vm"; return 1; }
+
+  [[ -n "$run_cleanup" ]] && prune_backups "$destination"
+}
+
+prune_backups() {
+  local backup_directory="$1"
+  mapfile -t backup_files < <(find "$backup_directory" -maxdepth 1 -name "*.tar.gz" -printf '%T@ %p\n' | sort -n | head -n "-${files_to_keep}" | cut -d' ' -f2-)
+  
+  if [[ ${#backup_files[@]} -gt 0 ]]; then
+    echo "Removing ${#qcow2_files[@]} old backup files for $vm (keeping last $total_files_to_keep files)"
+    printf '%s\0' "${backup_files[@]}" | xargs -0 rm -fv
+  else
+    echo "No old backups to remove for $vm"
+  fi
+
 }
 
 main "$@"