Solved bug concerning non running containers

docker-volume-backup.sh

@@ -15,6 +15,10 @@ do
   containers="$(docker ps --filter volume="$volume_name" --format '{{.Names}}')";
   containers_array=($containers)
   container=${containers_array[0]}
+  if [ -z "$containers" ]
+    then
+      echo "skipped due to no running containers using this volume."
+    else
       echo "stop containers:" && docker stop $containers
       for source_path in $(docker inspect --format "{{ range .Mounts }}{{ if eq .Type \"volume\"}}{{ if eq .Name \"$volume_name\"}}{{ println .Destination }}{{ end }}{{ end }}{{ end }}" "$container");
       do
@@ -39,5 +43,6 @@ do
         rsync -abP --delete --delete-excluded --log-file=$log_path --backup-dir=$raw_backup_dir_path '$source_path/' $raw_destination_path";
         echo "start containers:" && docker start $reverse_containers;
       done
+  fi
   echo "end backup routine: $volume_name";
 done