Create the RoutedMixin class

It will be used both in the app, and later blueprint classes.

calsocial/utils.py

@@ -68,3 +68,51 @@ def force_locale(locale):
         babel.locale_selector_func = orig_locale_selector_func
         for key, value in orig_attrs.items():
             setattr(ctx, key, value)
+
+
+class RoutedMixin:
+    """Mixin to lazily register class methods as routes
+
+    Works both for `Flask` and `Blueprint` objects.
+
+    Example::
+
+    class MyBlueprint(Blueprint, RoutedMixin):
+        def __init__(self, *args, **kwargs):
+            do_whatever_you_like()
+
+            RoutedMixin.register_routes(self)
+
+        @RoutedMixin.route('/')
+        def index(self):
+            return 'Hello, World!'
+    """
+
+    def register_routes(self):
+        for attr_name in self.__dir__():
+            attr = getattr(self, attr_name)
+
+            if not callable(attr):
+                continue
+
+            args, kwargs = getattr(attr, 'routing', (None, None))
+
+            if args is None:
+                continue
+
+            self.route(*args, **kwargs)(attr)
+
+    @staticmethod
+    def route(*args, **kwargs):
+        """Mark a function as a future route
+
+        Such functions will be iterated over when the application is initialised.  ``*args`` and
+        ``**kwargs`` will be passed verbatim to `Flask.route()`.
+        """
+
+        def decorator(func):  # pylint: disable=missing-docstring
+            setattr(func, 'routing', (args, kwargs))
+
+            return func
+
+        return decorator