improved proxy implementation.

proxy must now contain all public methods that the subject has.

pypatterns/structural/proxy.py

@@ -1,4 +1,7 @@
-class Proxy(object):
+from abc import ABCMeta
+
+
+class Proxy(object, metaclass=ABCMeta):
     """
     Base Proxy class as part of the Proxy design pattern.
     """
@@ -9,6 +12,22 @@ class Proxy(object):
         @param subject: The real subject this proxy calls upon.
         """
         self._subject = subject
+        self._validate()
+
+    def _validate(self):
+        """
+        Validate that the subject and this proxy follow the same interface.
+
+        @raise AttributeError: If the subject and this proxy do not follow the same interface.
+        """
+        for attr in dir(self._subject):
+            if attr.startswith('_') or attr.startswith('__'):
+                continue
+
+            elif not callable(getattr(self._subject, attr, None)) or not callable(getattr(self, attr, None)):
+                raise AttributeError('Subject and Proxy must follow same interface')
+
+