178: Registrar now subclasses from DictProxy; made Registrar.__iter__ behave same as the other container emulation in plugable.py, and made the dictorary interface return the base and the attribute interface return the MagicDict; updated API class and unit tests

ipalib/plugable.py

@@ -546,7 +546,7 @@ class NameSpace(DictProxy):
         return '%s(<%d members>)' % (self.__class__.__name__, len(self))
 
 
-class Registrar(ReadOnly):
+class Registrar(DictProxy):
     """
     Collects plugin classes as they are registered.
 
@@ -561,30 +561,19 @@ class Registrar(ReadOnly):
         :param allowed: Base classes from which plugins accepted by this
             Registrar must subclass.
         """
-
-        class Val(ReadOnly):
-            """
-            Internal class used so that only one mapping is needed.
-            """
-            def __init__(self, base):
-                assert inspect.isclass(base)
-                self.base = base
-                self.name = base.__name__
-                self.sub_d = dict()
-                self.dictproxy = MagicDict(self.sub_d)
-                lock(self)
-
-        self.__allowed = allowed
-        self.__d = {}
+        self.__allowed = dict((base, {}) for base in allowed)
         self.__registered = set()
-        for base in self.__allowed:
-            val = Val(base)
-            assert not (
-                val.name in self.__d or hasattr(self, val.name)
-            )
-            self.__d[val.name] = val
-            setattr(self, val.name, val.dictproxy)
-        lock(self)
+        super(Registrar, self).__init__(
+            dict(self.__base_iter())
+        )
+
+    def __base_iter(self):
+        for (base, sub_d) in self.__allowed.iteritems():
+            assert inspect.isclass(base)
+            name = base.__name__
+            assert not hasattr(self, name)
+            setattr(self, name, MagicDict(sub_d))
+            yield (name, base)
 
     def __findbases(self, klass):
         """
@@ -597,12 +586,12 @@ class Registrar(ReadOnly):
         """
         assert inspect.isclass(klass)
         found = False
-        for base in self.__allowed:
+        for (base, sub_d) in self.__allowed.iteritems():
             if issubclass(klass, base):
                 found = True
-                yield base
+                yield (base, sub_d)
         if not found:
-            raise errors.SubclassError(klass, self.__allowed)
+            raise errors.SubclassError(klass, self.__allowed.keys())
 
     def __call__(self, klass, override=False):
         """
@@ -619,17 +608,15 @@ class Registrar(ReadOnly):
             raise errors.DuplicateError(klass)
 
         # Find the base class or raise SubclassError:
-        for base in self.__findbases(klass):
-            sub_d = self.__d[base.__name__].sub_d
-
+        for (base, sub_d) in self.__findbases(klass):
             # Check override:
             if klass.__name__ in sub_d:
-                # Must use override=True to override:
                 if not override:
+                    # Must use override=True to override:
                     raise errors.OverrideError(base, klass)
             else:
-                # There was nothing already registered to override:
                 if override:
+                    # There was nothing already registered to override:
                     raise errors.MissingOverrideError(base, klass)
 
             # The plugin is okay, add to sub_d:
@@ -638,29 +625,6 @@ class Registrar(ReadOnly):
         # The plugin is okay, add to __registered:
         self.__registered.add(klass)
 
-    def __getitem__(self, key):
-        """
-        Returns the MagicDict for plugins subclassed from the base named ``key``.
-        """
-        if key not in self.__d:
-            raise KeyError('no base class named %r' % key)
-        return self.__d[key].dictproxy
-
-    def __contains__(self, key):
-        """
-        Returns True if a base class named ``key`` is in this Registrar.
-        """
-        return key in self.__d
-
-    def __iter__(self):
-        """
-        Iterates through a (base, registered_plugins) tuple for each allowed
-        base.
-        """
-        for base in self.__allowed:
-            sub_d = self.__d[base.__name__].sub_d
-            yield (base, tuple(sub_d[k] for k in sorted(sub_d)))
-
 
 class API(DictProxy):
     """
@@ -687,16 +651,19 @@ class API(DictProxy):
                 plugin = instances[klass]
                 yield PluginProxy(base, plugin)
 
-        for (base, classes) in self.register:
-            namespace = NameSpace(plugin_iter(base, classes))
-            name = base.__name__
+        for name in self.register:
+            base = self.register[name]
+            magic = getattr(self.register, name)
+            namespace = NameSpace(
+                plugin_iter(base, (magic[k] for k in magic))
+            )
             assert not (
                 name in self.__d or hasattr(self, name)
             )
             self.__d[name] = namespace
             object.__setattr__(self, name, namespace)
 
-        for plugin in instances.values():
+        for plugin in instances.itervalues():
             plugin.finalize(self)
             lock(plugin)
             assert plugin.api is self

ipalib/tests/test_plugable.py

@@ -643,12 +643,17 @@ def test_Registrar():
     # Test creation of Registrar:
     r = plugable.Registrar(Base1, Base2)
 
+    # Test __iter__:
+    assert list(r) == ['Base1', 'Base2']
+
     # Test __hasitem__, __getitem__:
     for base in [Base1, Base2]:
-        assert base.__name__ in r
-        dp = r[base.__name__]
-        assert type(dp) is plugable.MagicDict
-        assert len(dp) == 0
+        name = base.__name__
+        assert name in r
+        assert r[name] is base
+        magic = getattr(r, name)
+        assert type(magic) is plugable.MagicDict
+        assert len(magic) == 0
 
     # Check that TypeError is raised trying to register something that isn't
     # a class:
@@ -660,12 +665,9 @@ def test_Registrar():
 
     # Check that registration works
     r(plugin1)
-    dp = r['Base1']
-    assert type(dp) is plugable.MagicDict
-    assert len(dp) == 1
-    assert r.Base1 is dp
-    assert dp['plugin1'] is plugin1
-    assert dp.plugin1 is plugin1
+    assert len(r.Base1) == 1
+    assert r.Base1['plugin1'] is plugin1
+    assert r.Base1.plugin1 is plugin1
 
     # Check that DuplicateError is raised trying to register exact class
     # again:
@@ -696,7 +698,7 @@ def test_Registrar():
     assert len(r.Base2) == 1
     assert r.Base2.plugin2 is plugin2
 
-    # Setup to test __iter__:
+    # Setup to test more registration:
     class plugin1a(Base1):
         pass
     r(plugin1a)
@@ -713,25 +715,16 @@ def test_Registrar():
         pass
     r(plugin2b)
 
-    m = {
-        'Base1': set([plugin1, plugin1a, plugin1b]),
-        'Base2': set([plugin2, plugin2a, plugin2b]),
-    }
-
-    # Now test __iter__:
-    for (base, plugins) in r:
-        assert base in [Base1, Base2]
-        assert set(plugins) == m[base.__name__]
-    assert len(list(r)) == 2
-
     # Again test __hasitem__, __getitem__:
     for base in [Base1, Base2]:
-        assert base.__name__ in r
-        dp = r[base.__name__]
-        assert len(dp) == 3
-        for key in dp:
-            klass = dp[key]
-            assert getattr(dp, key) is klass
+        name = base.__name__
+        assert name in r
+        assert r[name] is base
+        magic = getattr(r, name)
+        assert len(magic) == 3
+        for key in magic:
+            klass = magic[key]
+            assert getattr(magic, key) is klass
             assert issubclass(klass, base)