Use text_format_safe instead of text_format

Use text_format_safe for traversing plugin attributes

Change-Id: Ib21a7386fe7cea982c98cfeaaa26040463f72b9d
Closes-Bug: #1576197
Closes-Bug: #1614401
(cherry picked from commit a4b427fca4)

nailgun/nailgun/objects/cluster.py

@@ -44,6 +44,7 @@ from nailgun.policy.merge import NetworkRoleMergePolicy
 from nailgun.settings import settings
 from nailgun.utils import AttributesGenerator
 from nailgun.utils import dict_merge
+from nailgun.utils import text_format_safe
 from nailgun.utils import traverse
 
 
@@ -343,10 +344,13 @@ class Cluster(NailgunObject):
         # Merge plugins attributes into editable ones
         plugin_attrs = PluginManager.get_plugins_attributes(
             instance, all_versions=all_plugins_versions)
-        plugin_attrs = traverse(plugin_attrs, AttributesGenerator, {
-            'cluster': instance,
-            'settings': settings,
-        })
+
+        plugin_attrs = traverse(
+            plugin_attrs,
+            formatter=text_format_safe,
+            formatter_context={'cluster': instance, 'settings': settings},
+            keywords={'generator': AttributesGenerator.evaluate}
+        )
         attrs['editable'].update(plugin_attrs)
 
         return attrs

nailgun/nailgun/test/unit/test_objects.py

@@ -1453,6 +1453,20 @@ class TestClusterObject(BaseTestCase):
         self.db().refresh(config)
         self.assertFalse(config.is_active)
 
+    def test_get_attributes_with_plugin(self):
+        cluster = self.env.create_cluster(api=False)
+        self.env.create_plugin(
+            name='test_plugin',
+            version='1.0.0',
+            package_version='4.0.0',
+            cluster=cluster,
+            attributes_metadata=self.env.get_default_plugin_env_config(
+                value='{}')
+        )
+        attr = objects.Cluster.get_attributes(cluster, True)
+        plugin_attrs = attr.editable['test_plugin']['metadata']['versions'][0]
+        self.assertEqual('{}', plugin_attrs['plugin_name_text']['value'])
+
 
 class TestClusterObjectVirtRoles(BaseTestCase):