Auto-detect create_app and make_app factory functions

flask/cli.py

@@ -46,6 +46,21 @@ def find_best_app(module):
 
     if len(matches) == 1:
         return matches[0]
+
+    # Search for app factory callables.
+    for attr_name in 'create_app', 'make_app':
+        app_factory = getattr(module, attr_name, None)
+        if app_factory is not None and callable(app_factory):
+            try:
+                app = app_factory()
+                if app is not None and isinstance(app, Flask):
+                    return app
+            except TypeError:
+                raise NoAppException('Auto-detected "%s()" in module "%s", '
+                                     'but could not call it without '
+                                     'specifying arguments.'
+                                     % (attr_name, module.__name__))
+
     raise NoAppException('Failed to find application in module "%s".  Are '
                          'you sure it contains a Flask application?  Maybe '
                          'you wrapped it in a WSGI middleware or you are '