Add initial blueprint support (#432)

Author: davidmrdavid

azure/durable_functions/__init__.py

@@ -74,7 +74,8 @@ def validate_extension_bundles():
 
 try:
     # disabling linter on this line because it fails to recognize the conditional export
-    from .decorators import DFApp # noqa
+    from .decorators import DFApp, BluePrint # noqa
     __all__.append('DFApp')
+    __all__.append('BluePrint')
 except ModuleNotFoundError:
     pass

azure/durable_functions/decorators/__init__.py

@@ -1,8 +1,9 @@
 #  Copyright (c) Microsoft Corporation. All rights reserved.
 #  Licensed under the MIT License.
 """Decorator definitions for Durable Functions."""
-from .durable_app import DFApp
+from .durable_app import DFApp, BluePrint
 
 __all__ = [
-    "DFApp"
+    "DFApp",
+    "BluePrint"
 ]

azure/durable_functions/decorators/durable_app.py

@@ -11,10 +11,14 @@
 from functools import wraps
 
 
-class DFApp(FunctionRegister, TriggerApi, BindingApi):
-    """Durable Functions (DF) app.
+class BluePrint(TriggerApi, BindingApi):
+    """Durable Functions (DF) blueprint container.
+
+    It allows functions to be declared via trigger and binding decorators,
+    but does not automatically index/register these functions.
 
-    Exports the decorators required to register DF Function-types.
+    To register these functions, utilize the `register_functions` method from any
+    :class:`FunctionRegister` subclass, such as `DFApp`.
     """
 
     def __init__(self,
@@ -226,3 +230,12 @@ def decorator():
             return decorator()
 
         return wrap
+
+
+class DFApp(BluePrint, FunctionRegister):
+    """Durable Functions (DF) app.
+
+    Exports the decorators required to declare and index DF Function-types.
+    """
+
+    pass