load settings list like a pipeline

simple_settings/core.py

@@ -11,11 +11,11 @@ def __init__(self):
 
     def _setup(self):
         self._settings_module = self._get_settings_from_cmd_line()
-        if not self._settings_module:
+        if self._settings_module is None:
             self._settings_module = os.environ.get('settings')
-        if not self._settings_module:
+        if self._settings_module is None:
             raise RuntimeError('Settings are not configured')
-        self._load_settings_module()
+        self._load_settings_pipeline()
 
     def _get_settings_from_cmd_line(self):
         for arg in sys.argv:
@@ -25,8 +25,12 @@ def _get_settings_from_cmd_line(self):
                 except IndexError:
                     return None
 
-    def _load_settings_module(self):
-        module = importlib.import_module(self._settings_module)
+    def _load_settings_pipeline(self):
+        for settings_module in self._settings_module.split(','):
+            self._load_settings_module(settings_module)
+
+    def _load_settings_module(self, settings_module):
+        module = importlib.import_module(settings_module)
         for setting in dir(module):
             value = os.environ.get(setting, getattr(module, setting))
             self._dict[setting] = value

tests/samples/without_import.py

@@ -0,0 +1,5 @@
+# -*- coding: utf-8 -*-
+
+
+SOME_TEXT = u'some text'
+SIMPLE_INTEGER = 2

tests/test_settings.py

@@ -10,7 +10,7 @@ def get_settings_by_cmd_line(module_name):
         return _Settings()
 
 
-def get_settings_by_enviroment(module_name):
+def get_settings_by_environment(module_name):
     with patch('os.environ.get') as mock:
         mock.return_value = module_name
         from simple_settings.core import _Settings
@@ -25,10 +25,10 @@ def test_should_load_module_by_cmd_line(self):
 
         assert settings._settings_module == expect_module
 
-    def test_should_load_module_by_enviroment(self):
+    def test_should_load_module_by_environment(self):
         expect_module = 'tests.samples.complex'
         with patch.object(sys, 'argv', []):
-            settings = get_settings_by_enviroment(expect_module)
+            settings = get_settings_by_environment(expect_module)
 
         assert settings._settings_module == expect_module
 
@@ -43,6 +43,21 @@ def test_should_inherit_settings(self):
 
         assert settings.APPLICATION_NAME == u'Simple Settings'
 
+    def test_should_load_multiple_settings_by_pipeline(self):
+        settings = get_settings_by_cmd_line(
+            'tests.samples.simple,tests.samples.without_import'
+        )
+
+        assert settings.SIMPLE_STRING == u'simple'
+        assert settings.SOME_TEXT == u'some text'
+
+    def test_should_inherit_settings_with_pipeline(self):
+        settings = get_settings_by_cmd_line(
+            'tests.samples.simple,tests.samples.without_import'
+        )
+
+        assert settings.SIMPLE_INTEGER == 2
+
     def test_complex_settings(self):
         settings = get_settings_by_cmd_line('tests.samples.complex')
 
@@ -56,7 +71,7 @@ def test_settings_as_dict(self):
         assert settings_dict['SIMPLE_STRING'] == u'simple'
         assert settings_dict['SIMPLE_INTEGER'] == 1
 
-    def test_settings_override_by_enviroment(self):
+    def test_settings_override_by_environment(self):
         def _mock_env_side_effect(k, d=None):
             return u'simple from env' if k == 'SIMPLE_STRING' else d