Merge pull request #4 from jedipi/feature/subclassed-config-support

Feature/subclassed config support

.gitignore

@@ -40,4 +40,7 @@ output/*.html
 output/*/index.html
 
 # Sphinx
-docs/_build
+docs/_build
+
+# Pycharm
+.idea/

layeredconfig/layeredconfig.py

@@ -41,7 +41,7 @@ def __init__(self, *sources, **kwargs):
         :type cascade: bool
         :param writable: Whether configuration values should be mutable.
                          ``True`` by default. This does not affect
-                         :py:meth:`~Layeredconfig.set`. 
+                         :py:meth:`~Layeredconfig.set`.
         :type writable: bool
 
         """
@@ -67,7 +67,7 @@ def __init__(self, *sources, **kwargs):
                 # we couldn't get any subsections for source, perhaps
                 # because it's an "empty" source. Well, that's ok.
                 pass
-                
+
         for k in sectionkeys:
             # 2. find all subsections in all of our sources
             s = []
@@ -86,9 +86,9 @@ def __init__(self, *sources, **kwargs):
                                            empty=True,
                                            cascade=self._cascade))
             # 3. create a LayeredConfig object for the subsection
-            c = LayeredConfig(*s,
-                              cascade=self._cascade,
-                              writable=self._writable)
+            c = self.__class__(*s,
+                               cascade=self._cascade,
+                               writable=self._writable)
             c._sectionkey = k
             c._parent = self
             self._subsections[k] = c
@@ -104,12 +104,12 @@ def write(config):
         assignment. The modifications are written to the first
         writable source in this config object.
 
-        .. note:: 
+        .. note::
 
            This is a static method, ie not a method on any object
            instance. This is because all attribute access on a
            LayeredConfig object is meant to retrieve configuration
-           settings. 
+           settings.
 
         :param config: The configuration object to save
         :type  config: layeredconfig.LayeredConfig
@@ -133,7 +133,7 @@ def set(config, key, value, sourceid="defaults"):
         :param config: The configuration object to set values on
         :param key: The parameter name
         :param value: The new value
-        :param sourceid: The identifier for the underlying source that the 
+        :param sourceid: The identifier for the underlying source that the
                          value should be set on.
         """
         for source in config._sources:
@@ -153,7 +153,7 @@ def get(config, key, default=None):
             return default
 
 # These are methods i'd like to implement next
-#        
+#
 #    @staticmethod
 #    def where(config, key):
 #        """returns the identifier of a source where a given key is found, or None."""
@@ -195,7 +195,7 @@ def boolconvert(value):
         """Convert the string *value* to a boolean. ``"True"`` is converted to
         ``True`` and ``"False"`` is converted to ``False``.
 
-        .. note:: 
+        .. note::
 
            If value is neither "True" nor "False", it's returned unchanged.
 
@@ -251,7 +251,7 @@ def __getattr__(self, name):
             if source.typed(name):
                 return source.get(name)
             else:
-                # we need to find a typesource for this value. 
+                # we need to find a typesource for this value.
                 done = False
                 this = self
                 while not done:
@@ -273,7 +273,7 @@ def __getattr__(self, name):
         else:
             if self._cascade and self._parent:
                 return self._parent.__getattr__(name)
-        
+
         raise AttributeError("Configuration key %s doesn't exist" % name)
 
     def __setattr__(self, name, value):

tests/test_layeredconfig.py

@@ -26,7 +26,7 @@
 
 if sys.version_info < (2, 7, 0):  # pragma: no cover
     import unittest2 as unittest
-else: 
+else:
     import unittest
 import requests
 # The system under test
@@ -57,7 +57,7 @@ def _test_config_singlesection(self, cfg):
         bool_transform = self.transforms.get(bool, bool_type)
         self.assertIs(type(cfg.force), bool_type)
         self.assertEqual(cfg.force, bool_transform(True))
-        
+
         if list in self.supported_types:
             list_type = list
             list_want = ['foo', 'bar']
@@ -170,7 +170,7 @@ def test_has(self):
     def test_typed(self):
         for key in self.simple.keys():
             self.assertTrue(self.simple.typed(key))
-                
+
     def test_get(self):
         # FIXME: This test should be able to look at supported_types
         # like test_singlesection and test_subsections do, so derived
@@ -201,7 +201,7 @@ def test_layered_subsections(self):
         # file-based sources) -- if the highest-priority source has
         # subsections, and a lower-priority file-based source lacks
         # those subsections, bad things would happen.
-        # 
+        #
         # see https://github.com/staffanm/layeredconfig/issues/2
         cfg = LayeredConfig(self.complex, self.extra)
         self._test_layered_configs(cfg)
@@ -283,7 +283,7 @@ class TestINIFile(TestINIFileHelper, unittest.TestCase,
 
     supported_types = (str,)
     supports_nesting = False
-    
+
     def setUp(self):
         super(TestINIFile, self).setUp()
         self.simple = INIFile("simple.ini")
@@ -318,7 +318,7 @@ def test_inifile_default_as_root(self):
         # load a modified version of complex.ini
         with open("complex.ini") as fp:
             ini = fp.read()
-            
+
         with open("complex-otherroot.ini", "w") as fp:
             fp.write(ini.replace("[__root__]", "[DEFAULT]"))
         cfg = LayeredConfig(INIFile("complex-otherroot.ini",
@@ -398,7 +398,7 @@ def test_write(self):
 class TestJSONFile(unittest.TestCase, TestConfigSourceHelper):
 
     supported_types = (str, int, bool, list)
-    
+
     def setUp(self):
         with open("simple.json", "w") as fp:
             fp.write("""
@@ -502,7 +502,7 @@ def setUp(self):
 home: mydata
 processes: 4
 force: true
-extra: 
+extra:
 - foo
 - bar
 expires: 2014-10-15
@@ -666,7 +666,7 @@ def setUp(self):
         <string>otherdata</string>
 </dict>
 </plist>
-""")            
+""")
         self.simple = PListFile("simple.plist")
         self.complex = PListFile("complex.plist")
         self.extra = PListFile("extra.plist")
@@ -868,7 +868,7 @@ def test_set(self):
 class TestCommandlineConfigured(TestCommandline):
 
     supported_types = (str, int, bool, date, datetime, list)
-    
+
     def setUp(self):
         super(TestCommandlineConfigured, self).setUp()
         simp = argparse.ArgumentParser(description="This is a simple program")
@@ -915,7 +915,7 @@ def test_typed(self):
 class TestEnvironment(unittest.TestCase, TestConfigSourceHelper):
 
     supported_types = (str,)
-    
+
     simple = Environment({'MYAPP_HOME': 'mydata',
                           'MYAPP_PROCESSES': '4',
                           'MYAPP_FORCE': 'True',
@@ -982,7 +982,7 @@ def simple(self):
         requests.put(ETCD_BASE + "/extra", data={'value': "foo, bar"})
         requests.put(ETCD_BASE + "/expires", data={'value': "2014-10-15"})
         requests.put(ETCD_BASE + "/lastrun", data={'value': "2014-10-15 14:32:07"})
-        return EtcdStore() 
+        return EtcdStore()
 
     @property
     def complex(self):
@@ -1042,7 +1042,7 @@ def indexfilter(node):
         cfg.mymodule.extra = ['foo', 'baz', 'quux']
         # note that this will write the entire config incl cfg.extra,
         # not just the values in the 'mymodule' subsection.
-        LayeredConfig.write(cfg.mymodule) 
+        LayeredConfig.write(cfg.mymodule)
         want = """
 {
     "dir": true,
@@ -1328,6 +1328,19 @@ def test_list(self):
         self.assertEqual(set(['home', 'processes']),
                          set(cfg.subsection))
 
+    def test_subsection_respects_subclass(self):
+        defaults = {
+            'subsection': {
+                'processes': 4
+            }
+        }
+
+        class SubclassedLayeredConfig(LayeredConfig):
+            pass
+
+        cfg = SubclassedLayeredConfig(Defaults(defaults))
+        self.assertIsInstance(cfg.subsection, SubclassedLayeredConfig)
+
 
 class TestLayeredSubsections(unittest.TestCase):
 
@@ -1344,7 +1357,7 @@ def _test_subsection(self, primary, secondary, cls):
         finally:
             os.unlink("primary.txt")
             os.unlink("secondary.txt")
-            
+
     def test_layered_yaml(self):
         self._test_subsection("""a:
   b: b