Fix reporting of errors when validating parameters.

Print the attribute CLI name instead of its 'real' name.
The real name is usually the name of the corresponding LDAP
attribute, which is confusing to the user.

This way we get:
Invalid 'login': blablabla
instead of:
Invalid 'uid': blablabla

Another example:
Invalid 'hostname': blablabla
instead of:
Invalid 'fqdn': blablabla

Ticket #435

ipalib/parameters.py

@@ -748,8 +748,11 @@ class Param(ReadOnly):
         for rule in self.all_rules:
             error = rule(ugettext, value)
             if error is not None:
+                name = self.cli_name
+                if not name:
+                    name = self.name
                 raise ValidationError(
-                    name=self.name,
+                    name=name,
                     value=value,
                     index=index,
                     error=error,

ipalib/plugins/user.py

@@ -227,7 +227,13 @@ class user_add(LDAPCreate):
         config = ldap.get_ipa_config()[1]
         if 'ipamaxusernamelength' in config:
             if len(keys[-1]) > int(config.get('ipamaxusernamelength')[0]):
-                raise errors.ValidationError(name='uid', error=_('can be at most %(len)d characters' % dict(len = int(config.get('ipamaxusernamelength')[0]))))
+                raise errors.ValidationError(
+                    name=self.obj.primary_key.cli_name, error=_(
+                        'can be at most %(len)d characters' % dict(
+                            len = int(config.get('ipamaxusernamelength')[0])
+                        )
+                    )
+                )
         entry_attrs.setdefault('loginshell', config.get('ipadefaultloginshell'))
         # hack so we can request separate first and last name in CLI
         full_name = '%s %s' % (entry_attrs['givenname'], entry_attrs['sn'])