Add settings class cache invalidation method. Update common.tests.base.BaseTestCase

class to invalidate settings cache. Update tests using Django's TestCase to
BaseTestCase.

mayan/apps/smart_settings/classes.py

@@ -16,14 +16,6 @@ logger = logging.getLogger(__name__)
 class Namespace(object):
     _registry = {}
 
-    @classmethod
-    def get_all(cls):
-        return cls._registry.values()
-
-    @classmethod
-    def get(cls, name):
-        return cls._registry[name]
-
     @staticmethod
     def initialize():
         for app in apps.get_app_configs():
@@ -36,6 +28,19 @@ class Namespace(object):
                     'Imported settings.py file for app %s', app.name
                 )
 
+    @classmethod
+    def get_all(cls):
+        return cls._registry.values()
+
+    @classmethod
+    def get(cls, name):
+        return cls._registry[name]
+
+    @classmethod
+    def invalidate_cache_all(cls):
+        for namespace in cls.get_all():
+            namespace.invalidate_cache()
+
     def __unicode__(self):
         return unicode(self.label)
 
@@ -52,8 +57,16 @@ class Namespace(object):
     def add_setting(self, **kwargs):
         return Setting(namespace=self, **kwargs)
 
+    def invalidate_cache(self):
+        for setting in self.settings:
+            setting.invalidate_cache()
+
 
 class Setting(object):
+    @staticmethod
+    def deserialize_value(value):
+        return yaml.safe_load(value)
+
     @staticmethod
     def serialize_value(value):
         if isinstance(value, Promise):
@@ -61,10 +74,6 @@ class Setting(object):
 
         return yaml.safe_dump(value, allow_unicode=True)
 
-    @staticmethod
-    def deserialize_value(value):
-        return yaml.safe_load(value)
-
     def __init__(self, namespace, global_name, default, help_text=None, is_path=False):
         self.global_name = global_name
         self.default = default
@@ -75,6 +84,9 @@ class Setting(object):
     def __unicode__(self):
         return unicode(self.global_name)
 
+    def invalidate_cache(self):
+        self.loaded = False
+
     @property
     def serialized_value(self):
         return self.yaml