Use YAML SafeDumper to avoid adding YAML tags

Closes GitLab issue #599. Thanks to Frédéric Sheedy
(@fsheedy) for the report and debug information.

Signed-off-by: Roberto Rosario <roberto.rosario.gonzalez@gmail.com>

HISTORY.rst

@@ -4,6 +4,9 @@
   (@fsheedy) for the report.
 * Add PostgreSQL troubleshooting entry. Closes GitLab
   issues #523 and #602
+* Use YAML SafeDumper to avoid adding YAML datatype tags.
+  Closes GitLab issue #599. Thanks to Frédéric Sheedy
+  (@fsheedy) for the report and debug information.
 
 3.2 (2019-06-13)
 ================

docs/releases/3.2.1.rst

@@ -8,7 +8,13 @@ Released: June 14, 2019
 Changes
 -------
 
-- Fix sub cabinet creation view.
+- Fix sub cabinet creation view. Thanks to Frédéric Sheedy
+  (@fsheedy) for the report.
+- Add PostgreSQL troubleshooting entry. Closes GitLab
+  issues #523 and #602
+- Use YAML SafeDumper to avoid adding YAML datatype tags.
+  Closes GitLab issue #599. Thanks to Frédéric Sheedy
+  (@fsheedy) for the report and debug information.
 
 
 Removals
@@ -99,6 +105,7 @@ Bugs fixed or issues closed
 ---------------------------
 
 - :gitlab-issue:`523` PostgreSQL error about insufficient connections
+- :gitlab-issue:`599` Settings display !!python/unicode with values since 3.2
 - :gitlab-issue:`601` Error when creating new cabinet level
 - :gitlab-issue:`602` System stops responding for a minute every 10 minutes or so
 

mayan/apps/converter/managers.py

@@ -5,9 +5,9 @@ import logging
 import yaml
 
 try:
-    from yaml import CSafeLoader as SafeLoader, CDumper as Dumper
+    from yaml import CSafeLoader as SafeLoader, CSafeDumper as SafeDumper
 except ImportError:
-    from yaml import SafeLoader, Dumper
+    from yaml import SafeLoader, SafeDumper
 
 from django.contrib.contenttypes.models import ContentType
 from django.db import models, transaction
@@ -24,7 +24,7 @@ class TransformationManager(models.Manager):
         self.create(
             content_type=content_type, object_id=obj.pk,
             name=transformation.name, arguments=yaml.dump(
-                data=arguments, Dumper=Dumper
+                data=arguments, Dumper=SafeDumper
             )
         )
 

mayan/apps/smart_settings/classes.py

@@ -9,9 +9,9 @@ import sys
 import yaml
 
 try:
-    from yaml import CSafeLoader as SafeLoader, CDumper as Dumper
+    from yaml import CSafeLoader as SafeLoader, CSafeDumper as SafeDumper
 except ImportError:
-    from yaml import SafeLoader, Dumper
+    from yaml import SafeLoader, SafeDumper
 
 from django.apps import apps
 from django.conf import settings
@@ -84,11 +84,23 @@ class Setting(object):
         return yaml.load(stream=value, Loader=SafeLoader)
 
     @staticmethod
-    def serialize_value(value):
-        if isinstance(value, Promise):
-            value = force_text(value)
+    def express_promises(value):
+        """
+        Walk all the elements of a value and force promises to text
+        """
+        if isinstance(value, (list, tuple)):
+            return [Setting.express_promises(item) for item in value]
+        elif isinstance(value, Promise):
+            return force_text(value)
+        else:
+            return value
 
-        result = yaml.dump(data=value, allow_unicode=True, Dumper=Dumper)
+    @staticmethod
+    def serialize_value(value):
+        result = yaml.dump(
+            data=Setting.express_promises(value), allow_unicode=True,
+            Dumper=SafeDumper
+        )
         # safe_dump returns bytestrings
         # Disregard the last 3 dots that mark the end of the YAML document
         if force_text(result).endswith('...\n'):
@@ -103,13 +115,10 @@ class Setting(object):
         for setting in cls.get_all():
             if (namespace and setting.namespace.name == namespace) or not namespace:
                 if (filter_term and filter_term.lower() in setting.global_name.lower()) or not filter_term:
-                    if isinstance(setting.value, Promise):
-                        dictionary[setting.global_name] = force_text(setting.value)
-                    else:
-                        dictionary[setting.global_name] = setting.value
+                    dictionary[setting.global_name] = Setting.express_promises(setting.value)
 
         return yaml.dump(
-            data=dictionary, default_flow_style=False, Dumper=Dumper
+            data=dictionary, default_flow_style=False, Dumper=SafeDumper
         )
 
     @classmethod

mayan/apps/smart_settings/tests/test_classes.py

@@ -2,9 +2,15 @@ from __future__ import absolute_import, unicode_literals
 
 import os
 
+from pathlib2 import Path
+
+from django.conf import settings
+
 from mayan.apps.common.settings import setting_paginate_by
 from mayan.apps.common.tests import BaseTestCase
 
+from ..classes import Setting
+
 from .literals import ENVIRONMENT_TEST_NAME, ENVIRONMENT_TEST_VALUE
 
 
@@ -14,3 +20,20 @@ class ClassesTestCase(BaseTestCase):
             'MAYAN_{}'.format(ENVIRONMENT_TEST_NAME)
         ] = ENVIRONMENT_TEST_VALUE
         self.assertTrue(setting_paginate_by.value, ENVIRONMENT_TEST_VALUE)
+
+    def test_config_backup_creation(self):
+        path_config_backup = Path(settings.CONFIGURATION_LAST_GOOD_FILEPATH)
+        path_config_backup.unlink()
+
+        Setting.save_last_known_good()
+        self.assertTrue(path_config_backup.exists())
+
+    def test_config_backup_creation_no_tags(self):
+        path_config_backup = Path(settings.CONFIGURATION_LAST_GOOD_FILEPATH)
+        path_config_backup.unlink()
+
+        Setting.save_last_known_good()
+        self.assertTrue(path_config_backup.exists())
+
+        with path_config_backup.open(mode='r') as file_object:
+            self.assertFalse('!!python/' in file_object.read())