DurableClient Converter (#206)

* sample durableClient converter

* dc converter & test

* lint

* removed unnecessary funcs

* typo

---------

Co-authored-by: Victoria Hall <victoria.hall@microsoft.com>

azure/functions/durable_functions.py

@@ -124,3 +124,12 @@ class ActivityTriggerConverter(meta.InConverter,
     @classmethod
     def has_implicit_output(cls) -> bool:
         return True
+
+
+# Durable Functions Durable Client Bindings
+class DurableClientConverter(meta.InConverter,
+                             meta.OutConverter,
+                             binding='durableClient'):
+    @classmethod
+    def has_implicit_output(cls) -> bool:
+        return False

tests/test_durable_functions.py

@@ -7,7 +7,8 @@ import json
 from azure.functions.durable_functions import (
     OrchestrationTriggerConverter,
     EnitityTriggerConverter,
-    ActivityTriggerConverter
+    ActivityTriggerConverter,
+    DurableClientConverter
 )
 from azure.functions._durable_functions import (
     OrchestrationContext,
@@ -213,6 +214,11 @@ class TestDurableFunctions(unittest.TestCase):
             ActivityTriggerConverter.has_implicit_output()
         )
 
+    def test_durable_client_no_implicit_return(self):
+        self.assertFalse(
+            DurableClientConverter.has_implicit_output()
+        )
+
     def test_enitity_trigger_check_output_type_annotation(self):
         self.assertTrue(
             EnitityTriggerConverter.check_output_type_annotation(pytype=None)