optional string

code/manifests/init.pp

@@ -48,7 +48,7 @@ class dirac (String $dirac_user = 'dirac', String $dirac_group = 'dirac',
             String $nginx_tpl_path = 'dirac/nginx.conf.erb',
             String $install_tpl_path = 'dirac/install.cfg.erb',
             String $rpm_repo = 'http://cern.ch/diracproject/rpm/$releasever',
-            String $cloud_tpl_path = undef,
+            Optional[String] $cloud_tpl_path = undef,
             Array $teigi_keys = [],
             Hash $dirac_config_args = {},
             Boolean $oracle_support = false,
@@ -252,7 +252,7 @@ class dirac (String $dirac_user = 'dirac', String $dirac_group = 'dirac',
   }
 
 
-  if $cloud_tpl_path != '' {
+  if $cloud_tpl_path {
     teigi::secret::sub_file{'/opt/dirac/etc/cloud.auth':
       teigi_keys => $teigi_keys,
       content    => template($cloud_tpl_path),