Added support for Entity Trigger

azure/functions/_durable_functions.py

@@ -109,3 +109,31 @@ def __repr__(self):
 
     def __str__(self):
         return self.__body
+
+
+class EntityContext(_abc.OrchestrationContext):
+    """A durable function entity context.
+
+    :param str body:
+        The body of orchestration context json.
+    """
+
+    def __init__(self,
+                 body: Union[str, bytes]) -> None:
+        if isinstance(body, str):
+            self.__body = body
+        if isinstance(body, bytes):
+            self.__body = body.decode('utf-8')
+
+    @property
+    def body(self) -> str:
+        return self.__body
+
+    def __repr__(self):
+        return (
+            f'<azure.EntityContext '
+            f'body={self.body}>'
+        )
+
+    def __str__(self):
+        return self.__body

azure/functions/durable_functions.py

@@ -39,6 +39,36 @@ def has_implicit_output(cls) -> bool:
         return True
 
 
+class EnitityTriggerConverter(meta.InConverter,
+                              meta.OutConverter,
+                              binding='entityTrigger',
+                              trigger=True):
+    @classmethod
+    def check_input_type_annotation(cls, pytype):
+        return issubclass(pytype, _durable_functions.EntityContext)
+
+    @classmethod
+    def check_output_type_annotation(cls, pytype):
+        # Implicit output should accept any return type
+        return True
+
+    @classmethod
+    def decode(cls,
+               data: meta.Datum, *,
+               trigger_metadata) -> _durable_functions.EntityContext:
+        return _durable_functions.EntityContext(data.value)
+
+    @classmethod
+    def encode(cls, obj: typing.Any, *,
+               expected_type: typing.Optional[type]) -> meta.Datum:
+        # Durable function context should be a json
+        return meta.Datum(type='json', value=obj)
+
+    @classmethod
+    def has_implicit_output(cls) -> bool:
+        return True
+
+
 # Durable Function Activity Trigger
 class ActivityTriggerConverter(meta.InConverter,
                                meta.OutConverter,