From 39ee2ba8a090e1203e09c97cfd10666a5dd745c3 Mon Sep 17 00:00:00 2001
From: David Justo <david.justo.1996@gmail.com>
Date: Thu, 16 Jul 2020 17:11:44 -0700
Subject: [PATCH 01/13] type-checked the project

---
 .../models/DurableHttpRequest.py              | 27 +++----
 .../models/DurableOrchestrationBindings.py    |  8 +-
 .../models/DurableOrchestrationClient.py      | 35 +++++----
 .../models/DurableOrchestrationContext.py     | 75 +++++++++----------
 .../models/DurableOrchestrationStatus.py      | 40 +++++-----
 .../models/OrchestratorState.py               | 10 +--
 .../models/PurgeHistoryResult.py              | 11 +--
 .../durable_functions/models/RetryOptions.py  |  6 +-
 .../models/RpcManagementOptions.py            | 17 ++++-
 azure/durable_functions/models/Task.py        |  2 +-
 azure/durable_functions/models/TokenSource.py |  6 +-
 .../models/actions/CallActivityAction.py      |  8 +-
 .../actions/CallActivityWithRetryAction.py    |  8 +-
 .../models/actions/CallHttpAction.py          |  4 +-
 .../models/actions/ContinueAsNewAction.py     |  6 +-
 .../models/actions/CreateTimerAction.py       | 11 +--
 .../actions/WaitForExternalEventAction.py     |  6 +-
 .../models/history/HistoryEvent.py            |  4 +-
 .../models/utils/http_utils.py                |  8 +-
 azure/durable_functions/orchestrator.py       |  8 +-
 azure/durable_functions/tasks/call_http.py    |  7 +-
 azure/durable_functions/tasks/create_timer.py |  2 +-
 azure/durable_functions/tasks/new_uuid.py     |  5 +-
 azure/durable_functions/tasks/timer_task.py   |  5 +-
 .../DurableTrigger/__init__.py                |  3 +-
 samples/function_chaining/local.settings.json |  2 +-
 26 files changed, 168 insertions(+), 156 deletions(-)

diff --git a/azure/durable_functions/models/DurableHttpRequest.py b/azure/durable_functions/models/DurableHttpRequest.py
index 9fffa601..eab80530 100644
--- a/azure/durable_functions/models/DurableHttpRequest.py
+++ b/azure/durable_functions/models/DurableHttpRequest.py
@@ -1,19 +1,20 @@
-from typing import Dict, Any
+from typing import Dict, Any, Union, Optional
 
-from azure.durable_functions.models import TokenSource
+from azure.durable_functions.models.TokenSource import TokenSource
 from azure.durable_functions.models.utils.json_utils import add_attrib, add_json_attrib
 
 
 class DurableHttpRequest:
     """Data structure representing a durable HTTP request."""
 
-    def __init__(self, method: str, uri: str, content: str = None, headers: Dict[str, str] = None,
-                 token_source: TokenSource = None):
+    def __init__(self, method: str, uri: str, content: Optional[str] = None,
+                 headers: Optional[Dict[str, str]] = None,
+                 token_source: Optional[TokenSource] = None):
         self._method: str = method
         self._uri: str = uri
-        self._content: str = content
-        self._headers: Dict[str, str] = headers
-        self._token_source: TokenSource = token_source
+        self._content: Optional[str] = content
+        self._headers: Optional[Dict[str, str]] = headers
+        self._token_source: Optional[TokenSource] = token_source
 
     @property
     def method(self) -> str:
@@ -26,29 +27,29 @@ def uri(self) -> str:
         return self._uri
 
     @property
-    def content(self) -> str:
+    def content(self) -> Optional[str]:
         """Get the HTTP request content."""
         return self._content
 
     @property
-    def headers(self) -> Dict[str, str]:
+    def headers(self) -> Optional[Dict[str, str]]:
         """Get the HTTP request headers."""
         return self._headers
 
     @property
-    def token_source(self) -> TokenSource:
+    def token_source(self) -> Optional[TokenSource]:
         """Get the source of OAuth token to add to the request."""
         return self._token_source
 
-    def to_json(self) -> Dict[str, Any]:
+    def to_json(self) -> Dict[str, Union[str, int]]:
         """Convert object into a json dictionary.
 
         Returns
         -------
-        Dict[str, Any]
+        Dict[str, Union[str, int]]
             The instance of the class converted into a json dictionary
         """
-        json_dict = {}
+        json_dict: Dict[str, Union[str, int]] = {}
         add_attrib(json_dict, self, 'method')
         add_attrib(json_dict, self, 'uri')
         add_attrib(json_dict, self, 'content')
diff --git a/azure/durable_functions/models/DurableOrchestrationBindings.py b/azure/durable_functions/models/DurableOrchestrationBindings.py
index bb2ca7c1..00f613a5 100644
--- a/azure/durable_functions/models/DurableOrchestrationBindings.py
+++ b/azure/durable_functions/models/DurableOrchestrationBindings.py
@@ -1,5 +1,5 @@
 import json
-from typing import Dict
+from typing import Dict, Optional
 
 from azure.durable_functions.models.FunctionContext import FunctionContext
 
@@ -13,11 +13,11 @@ class DurableOrchestrationBindings:
 
     # parameter names are as defined by JSON schema and do not conform to PEP8 naming conventions
     def __init__(self, taskHubName: str, creationUrls: Dict[str, str],
-                 managementUrls: Dict[str, str], rpcBaseUrl: str = None, **kwargs):
+                 managementUrls: Dict[str, str], rpcBaseUrl: Optional[str] = None, **kwargs):
         self._task_hub_name: str = taskHubName
         self._creation_urls: Dict[str, str] = creationUrls
         self._management_urls: Dict[str, str] = managementUrls
-        self._rpc_base_url: str = rpcBaseUrl
+        self._rpc_base_url: Optional[str] = rpcBaseUrl
         self._client_data = FunctionContext(**kwargs)
 
     @property
@@ -36,7 +36,7 @@ def management_urls(self) -> Dict[str, str]:
         return self._management_urls
 
     @property
-    def rpc_base_url(self) -> str:
+    def rpc_base_url(self) -> Optional[str]:
         """Get the base url communication between out of proc workers and the function host."""
         return self._rpc_base_url
 
diff --git a/azure/durable_functions/models/DurableOrchestrationClient.py b/azure/durable_functions/models/DurableOrchestrationClient.py
index c96f370d..8614e4bd 100644
--- a/azure/durable_functions/models/DurableOrchestrationClient.py
+++ b/azure/durable_functions/models/DurableOrchestrationClient.py
@@ -1,6 +1,6 @@
 import json
 from datetime import datetime
-from typing import List, Any, Awaitable
+from typing import List, Any, Awaitable, Optional, Union, Dict
 from time import time
 from asyncio import sleep
 from urllib.parse import urlparse, quote
@@ -11,7 +11,7 @@
 from .DurableOrchestrationStatus import DurableOrchestrationStatus
 from .RpcManagementOptions import RpcManagementOptions
 from .OrchestrationRuntimeStatus import OrchestrationRuntimeStatus
-from ..models import DurableOrchestrationBindings
+from ..models.DurableOrchestrationBindings import DurableOrchestrationBindings
 from .utils.http_utils import get_async_request, post_async_request, delete_async_request
 from azure.functions._durable_functions import _serialize_custom_object
 
@@ -44,8 +44,8 @@ def __init__(self, context: str):
 
     async def start_new(self,
                         orchestration_function_name: str,
-                        instance_id: str = None,
-                        client_input: object = None) -> Awaitable[str]:
+                        instance_id: Optional[str] = None,
+                        client_input: object = None) -> str:
         """Start a new instance of the specified orchestrator function.
 
         If an orchestration instance with the specified ID already exists, the
@@ -69,20 +69,22 @@ async def start_new(self,
         request_url = self._get_start_new_url(
             instance_id=instance_id, orchestration_function_name=orchestration_function_name)
 
-        response = await self._post_async_request(request_url, self._get_json_input(client_input))
+        response: List[Any] = await self._post_async_request(
+            request_url, self._get_json_input(client_input))
 
-        if response[0] <= 202 and response[1]:
+        status_code: int = response[0]
+        if status_code <= 202 and response[1]:
             return response[1]["id"]
-        elif response[0] == 400:
+        elif status_code == 400:
             # Orchestrator not found, report clean exception
-            exception_data = response[1]
+            exception_data: Dict[str, str] = response[1]
             exception_message = exception_data["ExceptionMessage"]
             raise Exception(exception_message)
         else:
             # Catch all: simply surfacing the durable-extension exception
             # we surface the stack trace too, since this may be a more involed exception
-            exception_message = response[1]
-            raise Exception(exception_message)
+            ex_message: Any = response[1]
+            raise Exception(ex_message)
 
     def create_check_status_response(self, request, instance_id):
         """Create a HttpResponse that contains useful information for \
@@ -250,7 +252,8 @@ async def get_status_all(self) -> List[DurableOrchestrationStatus]:
         if error_message:
             raise Exception(error_message)
         else:
-            return [DurableOrchestrationStatus.from_json(o) for o in response[1]]
+            statuses: List[Any] = response[1]
+            return [DurableOrchestrationStatus.from_json(o) for o in statuses]
 
     async def get_status_by(self, created_time_from: datetime = None,
                             created_time_to: datetime = None,
@@ -441,7 +444,7 @@ def _create_http_response(status_code: int, body: Any) -> func.HttpResponse:
         return func.HttpResponse(**response_args)
 
     @staticmethod
-    def _get_json_input(client_input: object) -> str:
+    def _get_json_input(client_input: object) -> Optional[str]:
         """Serialize the orchestrator input.
 
         Parameters
@@ -451,8 +454,10 @@ def _get_json_input(client_input: object) -> str:
 
         Returns
         -------
-        str
-            A string representing the JSON-serialization of `client_input`
+        Optional[str]
+            If `client_input` is not None, return a string representing
+            the JSON-serialization of `client_input`. Otherwise, returns
+            None
 
         Exceptions
         ----------
@@ -473,7 +478,7 @@ def _replace_url_origin(request_url, value_url):
         return value_url
 
     @staticmethod
-    def _parse_purge_instance_history_response(response: [int, Any]):
+    def _parse_purge_instance_history_response(response: List[Any]):
         switch_statement = {
             200: lambda: PurgeHistoryResult.from_json(response[1]),  # instance completed
             404: lambda: PurgeHistoryResult(instancesDeleted=0),  # instance not found
diff --git a/azure/durable_functions/models/DurableOrchestrationContext.py b/azure/durable_functions/models/DurableOrchestrationContext.py
index c975ba88..995eb141 100644
--- a/azure/durable_functions/models/DurableOrchestrationContext.py
+++ b/azure/durable_functions/models/DurableOrchestrationContext.py
@@ -1,8 +1,9 @@
 import json
 import datetime
-from typing import List, Any, Dict
+from typing import List, Any, Dict, Optional
 
-from . import (RetryOptions, TaskSet)
+from .RetryOptions import RetryOptions
+from .TaskSet import TaskSet
 from .FunctionContext import FunctionContext
 from .history import HistoryEvent, HistoryEventType
 from .actions import Action
@@ -30,27 +31,10 @@ def __init__(self,
         self._parent_instance_id: str = parentInstanceId
         self._custom_status: Any = None
         self._new_uuid_counter: int = 0
-        self.call_activity = lambda n, i=None: call_activity_task(
-            state=self.histories,
-            name=n,
-            input_=i)
-        self.call_activity_with_retry = \
-            lambda n, o, i=None: call_activity_with_retry_task(
-                state=self.histories,
-                retry_options=o,
-                name=n,
-                input_=i)
-        self.call_http = lambda method, uri, content=None, headers=None, token_source=None: \
-            call_http(
-                state=self.histories, method=method, uri=uri, content=content, headers=headers,
-                token_source=token_source)
         self.wait_for_external_event = lambda n: wait_for_external_event_task(
             state=self.histories,
             name=n)
-        self.new_uuid = lambda: new_uuid(context=self)
         self.continue_as_new = lambda i: continue_as_new(input_=i)
-        self.task_any = lambda t: task_any(tasks=t)
-        self.task_all = lambda t: task_all(tasks=t)
         self.create_timer = lambda d: create_timer_task(state=self.histories, fire_at=d)
         self.decision_started_event: HistoryEvent = \
             [e_ for e_ in self.histories
@@ -65,7 +49,7 @@ def __init__(self,
         # (consistent with Python Functions generic trigger/input bindings)
         if (isinstance(input, Dict)):
             input = json.dumps(input)
-        self._input: str = input
+        self._input: Any = input
 
     @classmethod
     def from_json(cls, json_string: str):
@@ -86,14 +70,14 @@ def from_json(cls, json_string: str):
         json_dict = json.loads(json_string)
         return cls(**json_dict)
 
-    def call_activity(self, name: str, input_=None) -> Task:
+    def call_activity(self, name: str, input_: Optional[Any] = None) -> Task:
         """Schedule an activity for execution.
 
         Parameters
         ----------
         name: str
             The name of the activity function to call.
-        input_:
+        input_: Optional[Any]
             The JSON-serializable input to pass to the activity function.
 
         Returns
@@ -101,11 +85,14 @@ def call_activity(self, name: str, input_=None) -> Task:
         Task
             A Durable Task that completes when the called activity function completes or fails.
         """
-        raise NotImplementedError("This is a placeholder.")
+        return call_activity_task(
+            state=self.histories,
+            name=name,
+            input_=input_)
 
     def call_activity_with_retry(self,
                                  name: str, retry_options: RetryOptions,
-                                 input_=None) -> Task:
+                                 input_: Optional[Any] = None) -> Task:
         """Schedule an activity for execution with retry options.
 
         Parameters
@@ -114,7 +101,7 @@ def call_activity_with_retry(self,
             The name of the activity function to call.
         retry_options: RetryOptions
             The retry options for the activity function.
-        input_:
+        input_: Optional[Any]
             The JSON-serializable input to pass to the activity function.
 
         Returns
@@ -123,10 +110,16 @@ def call_activity_with_retry(self,
             A Durable Task that completes when the called activity function completes or
             fails completely.
         """
+        return call_activity_with_retry_task(
+                state=self.histories,
+                retry_options=retry_options,
+                name=name,
+                input_=input_)
         raise NotImplementedError("This is a placeholder.")
 
-    def call_http(self, method: str, uri: str, content: str = None,
-                  headers: Dict[str, str] = None, token_source: TokenSource = None) -> Task:
+    def call_http(self, method: str, uri: str, content: Optional[str] = None,
+                  headers: Optional[Dict[str, str]] = None, 
+                  token_source: TokenSource = None) -> Task:
         """Schedule a durable HTTP call to the specified endpoint.
 
         Parameters
@@ -135,9 +128,9 @@ def call_http(self, method: str, uri: str, content: str = None,
             The HTTP request method.
         uri: str
             The HTTP request uri.
-        content: str
+        content: Optional[str]
             The HTTP request content.
-        headers: Dict[str, str]
+        headers: Optional[Dict[str, str]]
             The HTTP request headers.
         token_source: TokenSource
             The source of OAuth token to add to the request.
@@ -147,27 +140,29 @@ def call_http(self, method: str, uri: str, content: str = None,
         Task
             The durable HTTP request to schedule.
         """
-        raise NotImplementedError("This is a placeholder.")
+        return call_http(
+                state=self.histories, method=method, uri=uri, content=content, headers=headers,
+                token_source=token_source)
 
     def call_sub_orchestrator(self,
-                              name: str, input_=None,
-                              instance_id: str = None) -> Task:
+                              name: str, input_: Optional[Any] = None,
+                              instance_id: Optional[str] = None) -> Task:
         """Schedule an orchestration function named `name` for execution.
 
         Parameters
         ----------
         name: str
             The name of the orchestrator function to call.
-        input_:
+        input_: Optional[Any]
             The JSON-serializable input to pass to the orchestrator function.
-        instance_id: str
+        instance_id: Optional[str]
             A unique ID to use for the sub-orchestration instance. If `instanceId` is not
             specified, the extension will generate an id in the format `<calling orchestrator
             instance ID>:<#>`
         """
         raise NotImplementedError("This is a placeholder.")
 
-    def get_input(self) -> str:
+    def get_input(self) -> Optional[Any]:
         """Get the orchestration input."""
         return None if self._input is None else json.loads(self._input,
                                                            object_hook=_deserialize_custom_object)
@@ -185,7 +180,7 @@ def new_uuid(self) -> str:
         str
             New UUID that is safe for replay within an orchestration or operation.
         """
-        raise NotImplementedError("This is a placeholder.")
+        return new_uuid(context=self)
 
     def task_all(self, activities: List[Task]) -> TaskSet:
         """Schedule the execution of all activities.
@@ -205,7 +200,7 @@ def task_all(self, activities: List[Task]) -> TaskSet:
         TaskSet
             The results of all activities.
         """
-        raise NotImplementedError("This is a placeholder.")
+        return task_all(tasks=activities)
 
     def task_any(self, activities: List[Task]) -> TaskSet:
         """Schedule the execution of all activities.
@@ -225,7 +220,7 @@ def task_any(self, activities: List[Task]) -> TaskSet:
         TaskSet
             The first [[Task]] instance to complete.
         """
-        raise NotImplementedError("This is a placeholder.")
+        return task_any(tasks=activities)
 
     def set_custom_status(self, status: Any):
         """Set the customized orchestration status for your orchestrator function.
@@ -299,7 +294,7 @@ def parent_instance_id(self) -> str:
         return self._parent_instance_id
 
     @property
-    def current_utc_datetime(self) -> datetime:
+    def current_utc_datetime(self) -> datetime.datetime:
         """Get the current date/time.
 
         This date/time value is derived from the orchestration history. It
@@ -314,7 +309,7 @@ def current_utc_datetime(self) -> datetime:
         return self._current_utc_datetime
 
     @current_utc_datetime.setter
-    def current_utc_datetime(self, value: datetime):
+    def current_utc_datetime(self, value: datetime.datetime):
         self._current_utc_datetime = value
 
     @property
diff --git a/azure/durable_functions/models/DurableOrchestrationStatus.py b/azure/durable_functions/models/DurableOrchestrationStatus.py
index 38924157..b4990c9a 100644
--- a/azure/durable_functions/models/DurableOrchestrationStatus.py
+++ b/azure/durable_functions/models/DurableOrchestrationStatus.py
@@ -1,6 +1,6 @@
 from datetime import datetime
 from dateutil.parser import parse as dt_parse
-from typing import Any, List, Dict
+from typing import Any, List, Dict, Optional, Union
 
 from .OrchestrationRuntimeStatus import OrchestrationRuntimeStatus
 from .utils.json_utils import add_attrib, add_datetime_attrib
@@ -13,20 +13,22 @@ class DurableOrchestrationStatus:
     """
 
     # parameter names are as defined by JSON schema and do not conform to PEP8 naming conventions
-    def __init__(self, name: str = None, instanceId: str = None, createdTime: str = None,
-                 lastUpdatedTime: str = None, input: Any = None, output: Any = None,
-                 runtimeStatus: str = None, customStatus: Any = None, history: List[Any] = None,
+    def __init__(self, name: Optional[str] = None, instanceId: Optional[str] = None,
+                 createdTime: Optional[str] = None, lastUpdatedTime: Optional[str] = None,
+                 input: Optional[Any] = None, output: Optional[Any] = None,
+                 runtimeStatus: Optional[str] = None, customStatus: Optional[Any] = None,
+                 history: Optional[List[Any]] = None,
                  **kwargs):
-        self._name: str = name
-        self._instance_id: str = instanceId
-        self._created_time: datetime = dt_parse(createdTime) if createdTime is not None else None
-        self._last_updated_time: datetime = dt_parse(lastUpdatedTime) \
+        self._name: Optional[str] = name
+        self._instance_id: Optional[str] = instanceId
+        self._created_time: Optional[datetime] = dt_parse(createdTime) if createdTime is not None else None
+        self._last_updated_time: Optional[datetime] = dt_parse(lastUpdatedTime) \
             if lastUpdatedTime is not None else None
         self._input: Any = input
         self._output: Any = output
-        self._runtime_status: OrchestrationRuntimeStatus = runtimeStatus
+        self._runtime_status: Optional[str] = runtimeStatus
         self._custom_status: Any = customStatus
-        self._history: List[Any] = history
+        self._history: Optional[List[Any]] = history
         if kwargs is not None:
             for key, value in kwargs.items():
                 self.__setattr__(key, value)
@@ -65,15 +67,15 @@ def from_json(cls, json_obj: Any):
         else:
             return cls(**json_obj)
 
-    def to_json(self) -> Dict[str, Any]:
+    def to_json(self) -> Dict[str, Union[int, str]]:
         """Convert object into a json dictionary.
 
         Returns
         -------
-        Dict[str, Any]
+        Dict[str, Union[int, str]]
             The instance of the class converted into a json dictionary
         """
-        json = {}
+        json: Dict[str, Union[int, str]] = {}
         add_attrib(json, self, 'name')
         add_attrib(json, self, 'instance_id', 'instanceId')
         add_datetime_attrib(json, self, 'created_time', 'createdTime')
@@ -86,12 +88,12 @@ def to_json(self) -> Dict[str, Any]:
         return json
 
     @property
-    def name(self) -> str:
+    def name(self) -> Optional[str]:
         """Get the orchestrator function name."""
         return self._name
 
     @property
-    def instance_id(self) -> str:
+    def instance_id(self) -> Optional[str]:
         """Get the unique ID of the instance.
 
         The instance ID is generated and fixed when the orchestrator
@@ -102,7 +104,7 @@ def instance_id(self) -> str:
         return self._instance_id
 
     @property
-    def created_time(self) -> datetime:
+    def created_time(self) -> Optional[datetime]:
         """Get the time at which the orchestration instance was created.
 
         If the orchestration instance is in the [[Pending]] status, this
@@ -112,7 +114,7 @@ def created_time(self) -> datetime:
         return self._created_time
 
     @property
-    def last_updated_time(self) -> datetime:
+    def last_updated_time(self) -> Optional[datetime]:
         """Get the time at which the orchestration instance last updated its execution history."""
         return self._last_updated_time
 
@@ -127,7 +129,7 @@ def output(self) -> Any:
         return self._output
 
     @property
-    def runtime_status(self) -> OrchestrationRuntimeStatus:
+    def runtime_status(self) -> Optional[str]:
         """Get the runtime status of the orchestration instance."""
         return self._runtime_status
 
@@ -140,7 +142,7 @@ def custom_status(self) -> Any:
         return self._custom_status
 
     @property
-    def history(self) -> List[Any]:
+    def history(self) -> Optional[List[Any]]:
         """Get the execution history of the orchestration instance.
 
         The history log can be large and is therefore `undefined` by
diff --git a/azure/durable_functions/models/OrchestratorState.py b/azure/durable_functions/models/OrchestratorState.py
index fa44655c..6ed6b505 100644
--- a/azure/durable_functions/models/OrchestratorState.py
+++ b/azure/durable_functions/models/OrchestratorState.py
@@ -1,5 +1,5 @@
 import json
-from typing import List, Any, Dict
+from typing import List, Any, Dict, Optional, Union
 
 from .utils.json_utils import add_attrib
 from azure.durable_functions.models.actions.Action import Action
@@ -21,7 +21,7 @@ def __init__(self,
         self._is_done: bool = is_done
         self._actions: List[List[Action]] = actions
         self._output: Any = output
-        self._error: str = error
+        self._error: Optional[str] = error
         self._custom_status: Any = custom_status
 
     @property
@@ -54,7 +54,7 @@ def output(self):
         return self._output
 
     @property
-    def error(self) -> str:
+    def error(self) -> Optional[str]:
         """Get the error received when running the orchestration.
 
         Optional.
@@ -66,7 +66,7 @@ def custom_status(self):
         """Get the JSON-serializable value used by DurableOrchestrationContext.SetCustomStatus."""
         return self._custom_status
 
-    def to_json(self) -> Dict[str, Any]:
+    def to_json(self) -> Dict[str, Union[str, int]]:
         """Convert object into a json dictionary.
 
         Returns
@@ -74,7 +74,7 @@ def to_json(self) -> Dict[str, Any]:
         Dict[str, Any]
             The instance of the class converted into a json dictionary
         """
-        json_dict = {}
+        json_dict: Dict[str, Union[str, int]] = {}
         add_attrib(json_dict, self, '_is_done', 'isDone')
         self._add_actions(json_dict)
         if self._output:
diff --git a/azure/durable_functions/models/PurgeHistoryResult.py b/azure/durable_functions/models/PurgeHistoryResult.py
index 11e69416..4ccd48d0 100644
--- a/azure/durable_functions/models/PurgeHistoryResult.py
+++ b/azure/durable_functions/models/PurgeHistoryResult.py
@@ -1,4 +1,4 @@
-from typing import Any
+from typing import Union, Dict, Any
 
 
 class PurgeHistoryResult:
@@ -12,12 +12,12 @@ def __init__(self, instancesDeleted: int, **kwargs):
                 self.__setattr__(key, value)
 
     @classmethod
-    def from_json(cls, json_obj: Any):
+    def from_json(cls, json_obj: Dict[Any, Any]):
         """Convert the value passed into a new instance of the class.
 
         Parameters
         ----------
-        json_obj: any
+        json_obj: Dict[Any, Any]
             JSON object to be converted into an instance of the class
 
         Returns
@@ -25,10 +25,7 @@ def from_json(cls, json_obj: Any):
         PurgeHistoryResult
             New instance of the durable orchestration status class
         """
-        if isinstance(json_obj, str):
-            return cls(message=json_obj)
-        else:
-            return cls(**json_obj)
+        return cls(**json_obj)
 
     @property
     def instances_deleted(self):
diff --git a/azure/durable_functions/models/RetryOptions.py b/azure/durable_functions/models/RetryOptions.py
index 85d7f5a5..1770293c 100644
--- a/azure/durable_functions/models/RetryOptions.py
+++ b/azure/durable_functions/models/RetryOptions.py
@@ -1,4 +1,4 @@
-from typing import Any, Dict
+from typing import Any, Dict, Union
 
 from .utils.json_utils import add_attrib
 
@@ -46,7 +46,7 @@ def max_number_of_attempts(self) -> int:
         """
         return self._max_number_of_attempts
 
-    def to_json(self) -> Dict[str, Any]:
+    def to_json(self) -> Dict[str, Union[str, int]]:
         """Convert object into a json dictionary.
 
         Returns
@@ -54,7 +54,7 @@ def to_json(self) -> Dict[str, Any]:
         Dict[str, Any]
             The instance of the class converted into a json dictionary
         """
-        json_dict = {}
+        json_dict: Dict[str, Union[str, int]] = {}
 
         add_attrib(
             json_dict,
diff --git a/azure/durable_functions/models/RpcManagementOptions.py b/azure/durable_functions/models/RpcManagementOptions.py
index a703a9d7..9fcc09e0 100644
--- a/azure/durable_functions/models/RpcManagementOptions.py
+++ b/azure/durable_functions/models/RpcManagementOptions.py
@@ -1,5 +1,5 @@
 from datetime import datetime
-from typing import Any, List
+from typing import Any, List, Optional
 
 from azure.durable_functions.constants import DATETIME_STRING_FORMAT
 from azure.durable_functions.models.OrchestrationRuntimeStatus import OrchestrationRuntimeStatus
@@ -29,27 +29,36 @@ def _add_arg(query: List[str], name: str, value: Any):
             query.append(f'{name}={value}')
 
     @staticmethod
-    def _add_date_arg(query: List[str], name: str, value: datetime):
+    def _add_date_arg(query: List[str], name: str, value: Optional[datetime]):
         if value:
             date_as_string = value.strftime(DATETIME_STRING_FORMAT)
             RpcManagementOptions._add_arg(query, name, date_as_string)
 
-    def to_url(self, base_url: str) -> str:
+    def to_url(self, base_url: Optional[str]) -> str:
         """Get the url based on the options selected.
 
         Parameters
         ----------
         base_url: str
             The base url to prepend to the url path
+        
+        Raises
+        ------
+        ValueError
+            When the `base_url` argument is None
 
         Returns
         -------
         str
             The Url used to get orchestration status information
         """
+        if base_url is None:
+            # TODO: In JS we manage a "legacy app frontend code path. Here too?"
+            raise ValueError("orchestration bindings has not RPC base url")
+
         url = f"{base_url}instances/{self._instance_id if self._instance_id else ''}"
 
-        query = []
+        query: List[str] = []
 
         self._add_arg(query, 'taskHub', self._task_hub_name)
         self._add_arg(query, 'connectionName', self._connection_name)
diff --git a/azure/durable_functions/models/Task.py b/azure/durable_functions/models/Task.py
index 7fa71410..67ee0466 100644
--- a/azure/durable_functions/models/Task.py
+++ b/azure/durable_functions/models/Task.py
@@ -1,6 +1,6 @@
 from datetime import datetime
 
-from .actions import Action
+from .actions.Action import Action
 
 
 class Task:
diff --git a/azure/durable_functions/models/TokenSource.py b/azure/durable_functions/models/TokenSource.py
index bf5a322a..375b84bd 100644
--- a/azure/durable_functions/models/TokenSource.py
+++ b/azure/durable_functions/models/TokenSource.py
@@ -1,5 +1,5 @@
 from abc import ABC
-from typing import Dict, Any
+from typing import Dict, Any, Union
 
 from azure.durable_functions.models.utils.json_utils import add_attrib
 
@@ -41,7 +41,7 @@ def resource(self) -> str:
         """
         return self._resource
 
-    def to_json(self) -> Dict[str, Any]:
+    def to_json(self) -> Dict[str, Union[str, int]]:
         """Convert object into a json dictionary.
 
         Returns
@@ -49,6 +49,6 @@ def to_json(self) -> Dict[str, Any]:
         Dict[str, Any]
             The instance of the class converted into a json dictionary
         """
-        json_dict = {}
+        json_dict: Dict[str, Union[str, int]] = {}
         add_attrib(json_dict, self, 'resource')
         return json_dict
diff --git a/azure/durable_functions/models/actions/CallActivityAction.py b/azure/durable_functions/models/actions/CallActivityAction.py
index a3e8d58f..37361832 100644
--- a/azure/durable_functions/models/actions/CallActivityAction.py
+++ b/azure/durable_functions/models/actions/CallActivityAction.py
@@ -1,4 +1,4 @@
-from typing import Any, Dict
+from typing import Any, Dict, Union
 
 from .Action import Action
 from .ActionType import ActionType
@@ -26,15 +26,15 @@ def action_type(self) -> int:
         """Get the type of action this class represents."""
         return ActionType.CALL_ACTIVITY
 
-    def to_json(self) -> Dict[str, Any]:
+    def to_json(self) -> Dict[str, Union[str, int]]:
         """Convert object into a json dictionary.
 
         Returns
         -------
-        Dict[str, Any]
+        Dict[str, Union[str, int]]
             The instance of the class converted into a json dictionary
         """
-        json_dict = {}
+        json_dict: Dict[str, Union[str, int]] = {}
         add_attrib(json_dict, self, 'action_type', 'actionType')
         add_attrib(json_dict, self, 'function_name', 'functionName')
         add_attrib(json_dict, self, 'input_', 'input')
diff --git a/azure/durable_functions/models/actions/CallActivityWithRetryAction.py b/azure/durable_functions/models/actions/CallActivityWithRetryAction.py
index 7f769065..72fdba46 100644
--- a/azure/durable_functions/models/actions/CallActivityWithRetryAction.py
+++ b/azure/durable_functions/models/actions/CallActivityWithRetryAction.py
@@ -1,4 +1,4 @@
-from typing import Any, Dict
+from typing import Any, Dict, Union
 
 from .Action import Action
 from .ActionType import ActionType
@@ -26,15 +26,15 @@ def action_type(self) -> int:
         """Get the type of action this class represents."""
         return ActionType.CALL_ACTIVITY_WITH_RETRY
 
-    def to_json(self) -> Dict[str, Any]:
+    def to_json(self) -> Dict[str, Union[str, int]]:
         """Convert object into a json dictionary.
 
         Returns
         -------
-        Dict[str, Any]
+        Dict[str, Union[str, int]]
             The instance of the class converted into a json dictionary
         """
-        json_dict = {}
+        json_dict: Dict[str, Union[str, int]] = {}
 
         add_attrib(json_dict, self, 'action_type', 'actionType')
         add_attrib(json_dict, self, 'function_name', 'functionName')
diff --git a/azure/durable_functions/models/actions/CallHttpAction.py b/azure/durable_functions/models/actions/CallHttpAction.py
index 283f24df..2d592bf2 100644
--- a/azure/durable_functions/models/actions/CallHttpAction.py
+++ b/azure/durable_functions/models/actions/CallHttpAction.py
@@ -2,7 +2,7 @@
 
 from .Action import Action
 from .ActionType import ActionType
-from .. import DurableHttpRequest
+from ..DurableHttpRequest import DurableHttpRequest
 from ..utils.json_utils import add_attrib, add_json_attrib
 
 
@@ -29,7 +29,7 @@ def to_json(self) -> Dict[str, Any]:
         Dict[str, Any]
             The instance of the class converted into a json dictionary
         """
-        json_dict = {}
+        json_dict: Dict[str, Any] = {}
         add_attrib(json_dict, self, 'action_type', 'actionType')
         add_json_attrib(json_dict, self, 'http_request', 'httpRequest')
         return json_dict
diff --git a/azure/durable_functions/models/actions/ContinueAsNewAction.py b/azure/durable_functions/models/actions/ContinueAsNewAction.py
index 52d00d7b..eed20d52 100644
--- a/azure/durable_functions/models/actions/ContinueAsNewAction.py
+++ b/azure/durable_functions/models/actions/ContinueAsNewAction.py
@@ -1,4 +1,4 @@
-from typing import Any, Dict
+from typing import Any, Dict, Union
 
 from .Action import Action
 from .ActionType import ActionType
@@ -20,7 +20,7 @@ def action_type(self) -> int:
         """Get the type of action this class represents."""
         return ActionType.CONTINUE_AS_NEW
 
-    def to_json(self) -> Dict[str, Any]:
+    def to_json(self) -> Dict[str, Union[int, str]]:
         """Convert object into a json dictionary.
 
         Returns
@@ -28,7 +28,7 @@ def to_json(self) -> Dict[str, Any]:
         Dict[str, Any]
             The instance of the class converted into a json dictionary
         """
-        json_dict = {}
+        json_dict: Dict[str, Union[int, str]] = {}
         add_attrib(json_dict, self, 'action_type', 'actionType')
         add_attrib(json_dict, self, 'input_', 'input')
         return json_dict
diff --git a/azure/durable_functions/models/actions/CreateTimerAction.py b/azure/durable_functions/models/actions/CreateTimerAction.py
index f2c918eb..d50baf8e 100644
--- a/azure/durable_functions/models/actions/CreateTimerAction.py
+++ b/azure/durable_functions/models/actions/CreateTimerAction.py
@@ -1,11 +1,12 @@
-from typing import Any, Dict
+from typing import Any, Dict, Union
 
 from .ActionType import ActionType
+from .Action import Action
 from ..utils.json_utils import add_attrib, add_datetime_attrib
 import datetime
 
 
-class CreateTimerAction:
+class CreateTimerAction(Action):
     """Defines the structure of the Create Timer object.
 
     Returns
@@ -18,9 +19,9 @@ class CreateTimerAction:
         if the event fired is not of valid datetime object
     """
 
-    def __init__(self, fire_at: datetime, is_cancelled: bool = False):
+    def __init__(self, fire_at: datetime.datetime, is_cancelled: bool = False):
         self.action_type: ActionType = ActionType.CREATE_TIMER
-        self.fire_at: datetime = fire_at
+        self.fire_at: datetime.datetime = fire_at
         self.is_cancelled: bool = is_cancelled
 
         if not isinstance(self.fire_at, datetime.date):
@@ -35,7 +36,7 @@ def to_json(self) -> Dict[str, Any]:
         Dict[str, Any]
             The instance of the class converted into a json dictionary
         """
-        json_dict = {}
+        json_dict: Dict[str, Union[int, str]] = {}
         add_attrib(json_dict, self, 'action_type', 'actionType')
         add_datetime_attrib(json_dict, self, 'fire_at', 'fireAt')
         add_attrib(json_dict, self, 'is_cancelled', 'isCanceled')
diff --git a/azure/durable_functions/models/actions/WaitForExternalEventAction.py b/azure/durable_functions/models/actions/WaitForExternalEventAction.py
index 561c953d..70d9c290 100644
--- a/azure/durable_functions/models/actions/WaitForExternalEventAction.py
+++ b/azure/durable_functions/models/actions/WaitForExternalEventAction.py
@@ -1,4 +1,4 @@
-from typing import Any, Dict
+from typing import Any, Dict, Union
 
 from .Action import Action
 from .ActionType import ActionType
@@ -36,10 +36,10 @@ def to_json(self) -> Dict[str, Any]:
 
         Returns
         -------
-        Dict[str, Any]
+        Dict[str, Union[str, int]]
             The instance of the class converted into a json dictionary
         """
-        json_dict = {}
+        json_dict: Dict[str, Union[str, int]] = {}
 
         add_attrib(json_dict, self, 'action_type', 'actionType')
         add_attrib(json_dict, self, 'external_event_name', 'externalEventName')
diff --git a/azure/durable_functions/models/history/HistoryEvent.py b/azure/durable_functions/models/history/HistoryEvent.py
index c0897d19..84023944 100644
--- a/azure/durable_functions/models/history/HistoryEvent.py
+++ b/azure/durable_functions/models/history/HistoryEvent.py
@@ -12,7 +12,7 @@ def __init__(self, EventType: HistoryEventType, EventId: int, IsPlayed: bool, Ti
         self._event_type: HistoryEventType = EventType
         self._event_id: int = EventId
         self._is_played: bool = IsPlayed
-        self._timestamp: datetime = dt_parse(Timestamp)
+        self._timestamp: datetime.datetime = dt_parse(Timestamp)
         self._is_processed: bool = False
         if kwargs is not None:
             for key, value in kwargs.items():
@@ -74,7 +74,7 @@ def is_processed(self, value: bool):
         self._is_processed = value
 
     @property
-    def timestamp(self) -> datetime:
+    def timestamp(self) -> datetime.datetime:
         """Get the timestamp property.
 
         Returns
diff --git a/azure/durable_functions/models/utils/http_utils.py b/azure/durable_functions/models/utils/http_utils.py
index ef8cb8ed..62d28f21 100644
--- a/azure/durable_functions/models/utils/http_utils.py
+++ b/azure/durable_functions/models/utils/http_utils.py
@@ -1,9 +1,9 @@
-from typing import Any
+from typing import Any, List, Union
 
 import aiohttp
 
 
-async def post_async_request(url: str, data: Any = None) -> [int, Any]:
+async def post_async_request(url: str, data: Any = None) -> List[Union[int, Any]]:
     """Post request with the data provided to the url provided.
 
     Parameters
@@ -29,7 +29,7 @@ async def post_async_request(url: str, data: Any = None) -> [int, Any]:
             return [response.status, data]
 
 
-async def get_async_request(url: str) -> [int, Any]:
+async def get_async_request(url: str) -> List[Any]:
     """Get the data from the url provided.
 
     Parameters
@@ -50,7 +50,7 @@ async def get_async_request(url: str) -> [int, Any]:
             return [response.status, data]
 
 
-async def delete_async_request(url: str) -> [int, Any]:
+async def delete_async_request(url: str) -> List[Union[int, Any]]:
     """Delete the data from the url provided.
 
     Parameters
diff --git a/azure/durable_functions/orchestrator.py b/azure/durable_functions/orchestrator.py
index 74a6c20a..8361eea7 100644
--- a/azure/durable_functions/orchestrator.py
+++ b/azure/durable_functions/orchestrator.py
@@ -3,7 +3,7 @@
 Responsible for orchestrating the execution of the user defined generator
 function.
 """
-from typing import Callable, Iterator, Any
+from typing import Callable, Iterator, Any, Generator
 
 from .models import (
     DurableOrchestrationContext,
@@ -24,14 +24,14 @@ class Orchestrator:
     """
 
     def __init__(self,
-                 activity_func: Callable[[DurableOrchestrationContext], Iterator[Any]]):
+                 activity_func: Callable[[DurableOrchestrationContext], Generator[Any, Any, Any]]):
         """Create a new orchestrator for the user defined generator.
 
         Responsible for orchestrating the execution of the user defined
         generator function.
         :param activity_func: Generator function to orchestrate.
         """
-        self.fn: Callable[[DurableOrchestrationContext], Iterator[Any]] = activity_func
+        self.fn: Callable[[DurableOrchestrationContext], Generator[Any, Any, Any]] = activity_func
 
     def handle(self, context: DurableOrchestrationContext):
         """Handle the orchestration of the user defined generator function.
@@ -132,7 +132,7 @@ def _reset_timestamp(self):
                 self.durable_context.decision_started_event.timestamp
 
     @classmethod
-    def create(cls, fn: Callable[[DurableOrchestrationContext], Iterator[Any]]) \
+    def create(cls, fn: Callable[[DurableOrchestrationContext], Generator[Any, Any, Any]]) \
             -> Callable[[Any], str]:
         """Create an instance of the orchestration class.
 
diff --git a/azure/durable_functions/tasks/call_http.py b/azure/durable_functions/tasks/call_http.py
index 0fb51b4d..85ec228f 100644
--- a/azure/durable_functions/tasks/call_http.py
+++ b/azure/durable_functions/tasks/call_http.py
@@ -1,5 +1,5 @@
 import json
-from typing import Dict, List
+from typing import Dict, List, Optional
 
 from .task_utilities import find_task_scheduled, find_task_completed, find_task_failed, \
     set_processed, parse_history_event
@@ -12,8 +12,8 @@
     Task)
 
 
-def call_http(state: List[HistoryEvent], method: str, uri: str, content: str = None,
-              headers: Dict[str, str] = None, token_source: TokenSource = None) -> Task:
+def call_http(state: List[HistoryEvent], method: str, uri: str, content: Optional[str] = None,
+              headers: Dict[str, str] = None, token_source: Optional[TokenSource] = None) -> Task:
     """Get task used to schedule a durable HTTP call to the specified endpoint.
 
     Parameters
@@ -37,6 +37,7 @@ def call_http(state: List[HistoryEvent], method: str, uri: str, content: str = N
     Task
         The durable HTTP request to schedule.
     """
+    json_content: Optional[str] = None
     if content and content is not isinstance(content, str):
         json_content = json.dumps(content)
     else:
diff --git a/azure/durable_functions/tasks/create_timer.py b/azure/durable_functions/tasks/create_timer.py
index e775790b..00da0b61 100644
--- a/azure/durable_functions/tasks/create_timer.py
+++ b/azure/durable_functions/tasks/create_timer.py
@@ -7,7 +7,7 @@
 
 
 def create_timer_task(state: List[HistoryEvent],
-                      fire_at: datetime) -> TimerTask:
+                      fire_at: datetime.datetime) -> TimerTask:
     """Durable Timers are used in orchestrator function to implement delays.
 
     Parameters
diff --git a/azure/durable_functions/tasks/new_uuid.py b/azure/durable_functions/tasks/new_uuid.py
index 0807876b..43140824 100644
--- a/azure/durable_functions/tasks/new_uuid.py
+++ b/azure/durable_functions/tasks/new_uuid.py
@@ -1,6 +1,5 @@
 from uuid import uuid5, NAMESPACE_OID
 
-from azure.durable_functions.models import DurableOrchestrationContext
 from azure.durable_functions.constants import DATETIME_STRING_FORMAT
 
 URL_NAMESPACE: str = "9e952958-5e33-4daf-827f-2fa12937b875"
@@ -11,7 +10,7 @@ def _create_deterministic_uuid(namespace_value: str, name: str) -> str:
     return str(uuid5(namespace_uuid, name))
 
 
-def new_uuid(context: DurableOrchestrationContext) -> str:
+def new_uuid(context) -> str:
     """Create a new UUID that is safe for replay within an orchestration or operation.
 
     The default implementation of this method creates a name-based UUID
@@ -31,7 +30,7 @@ def new_uuid(context: DurableOrchestrationContext) -> str:
         New UUID that is safe for replay within an orchestration or operation.
     """
     uuid_name_value = \
-        f"{context.instance_id}" \
+        f"{context._instance_id}" \
         f"_{context.current_utc_datetime.strftime(DATETIME_STRING_FORMAT)}" \
         f"_{context._new_uuid_counter}"
     context._new_uuid_counter += 1
diff --git a/azure/durable_functions/tasks/timer_task.py b/azure/durable_functions/tasks/timer_task.py
index 0eaca181..fdd719fe 100644
--- a/azure/durable_functions/tasks/timer_task.py
+++ b/azure/durable_functions/tasks/timer_task.py
@@ -1,4 +1,5 @@
 from ..models.Task import Task
+from ..models.actions.CreateTimerAction import CreateTimerAction
 
 
 class TimerTask(Task):
@@ -14,8 +15,8 @@ class TimerTask(Task):
     ```
     """
 
-    def __init__(self, action, is_completed, timestamp, id_):
-        self._action = action
+    def __init__(self, action: CreateTimerAction, is_completed, timestamp, id_):
+        self._action: CreateTimerAction = action
         self._is_completed = is_completed
         self._timestamp = timestamp
         self._id = id_
diff --git a/samples/function_chaining/DurableTrigger/__init__.py b/samples/function_chaining/DurableTrigger/__init__.py
index e4eccba6..d3ceaed7 100755
--- a/samples/function_chaining/DurableTrigger/__init__.py
+++ b/samples/function_chaining/DurableTrigger/__init__.py
@@ -27,4 +27,5 @@ async def main(req: func.HttpRequest, starter: str, message):
     client = DurableOrchestrationClient(starter)
     instance_id = await client.start_new(function_name)
     response = client.create_check_status_response(req, instance_id)
-    message.set(response)
+    var = client.create_http_management_payload(instance_id)
+    message.set(str(var))
diff --git a/samples/function_chaining/local.settings.json b/samples/function_chaining/local.settings.json
index 853a5a84..a2ded917 100644
--- a/samples/function_chaining/local.settings.json
+++ b/samples/function_chaining/local.settings.json
@@ -1,7 +1,7 @@
 {
   "IsEncrypted": false,
   "Values": {
-    "AzureWebJobsStorage": "",
+    "AzureWebJobsStorage": "UseDevelopmentStorage=true",
     "FUNCTIONS_WORKER_RUNTIME": "python"
   }
 }

From 27baacf5a9ec9f99e5882b134c619cbeb96f3226 Mon Sep 17 00:00:00 2001
From: David Justo <david.justo.1996@gmail.com>
Date: Thu, 16 Jul 2020 19:56:25 -0700
Subject: [PATCH 02/13] linting

---
 .../models/DurableHttpRequest.py                  |  2 +-
 .../models/DurableOrchestrationClient.py          |  2 +-
 .../models/DurableOrchestrationContext.py         | 15 +++++++--------
 .../models/DurableOrchestrationStatus.py          |  4 ++--
 .../models/PurgeHistoryResult.py                  |  2 +-
 azure/durable_functions/models/RetryOptions.py    |  2 +-
 .../models/RpcManagementOptions.py                |  2 +-
 azure/durable_functions/models/TokenSource.py     |  2 +-
 .../models/actions/CallActivityAction.py          |  2 +-
 .../models/actions/CallActivityWithRetryAction.py |  2 +-
 .../models/actions/ContinueAsNewAction.py         |  2 +-
 11 files changed, 18 insertions(+), 19 deletions(-)

diff --git a/azure/durable_functions/models/DurableHttpRequest.py b/azure/durable_functions/models/DurableHttpRequest.py
index eab80530..c1c96c92 100644
--- a/azure/durable_functions/models/DurableHttpRequest.py
+++ b/azure/durable_functions/models/DurableHttpRequest.py
@@ -1,4 +1,4 @@
-from typing import Dict, Any, Union, Optional
+from typing import Dict, Union, Optional
 
 from azure.durable_functions.models.TokenSource import TokenSource
 from azure.durable_functions.models.utils.json_utils import add_attrib, add_json_attrib
diff --git a/azure/durable_functions/models/DurableOrchestrationClient.py b/azure/durable_functions/models/DurableOrchestrationClient.py
index 8614e4bd..2a9b6640 100644
--- a/azure/durable_functions/models/DurableOrchestrationClient.py
+++ b/azure/durable_functions/models/DurableOrchestrationClient.py
@@ -1,6 +1,6 @@
 import json
 from datetime import datetime
-from typing import List, Any, Awaitable, Optional, Union, Dict
+from typing import List, Any, Optional, Dict
 from time import time
 from asyncio import sleep
 from urllib.parse import urlparse, quote
diff --git a/azure/durable_functions/models/DurableOrchestrationContext.py b/azure/durable_functions/models/DurableOrchestrationContext.py
index 995eb141..ba80ac3f 100644
--- a/azure/durable_functions/models/DurableOrchestrationContext.py
+++ b/azure/durable_functions/models/DurableOrchestrationContext.py
@@ -111,14 +111,13 @@ def call_activity_with_retry(self,
             fails completely.
         """
         return call_activity_with_retry_task(
-                state=self.histories,
-                retry_options=retry_options,
-                name=name,
-                input_=input_)
-        raise NotImplementedError("This is a placeholder.")
+            state=self.histories,
+            retry_options=retry_options,
+            name=name,
+            input_=input_)
 
     def call_http(self, method: str, uri: str, content: Optional[str] = None,
-                  headers: Optional[Dict[str, str]] = None, 
+                  headers: Optional[Dict[str, str]] = None,
                   token_source: TokenSource = None) -> Task:
         """Schedule a durable HTTP call to the specified endpoint.
 
@@ -141,8 +140,8 @@ def call_http(self, method: str, uri: str, content: Optional[str] = None,
             The durable HTTP request to schedule.
         """
         return call_http(
-                state=self.histories, method=method, uri=uri, content=content, headers=headers,
-                token_source=token_source)
+            state=self.histories, method=method, uri=uri, content=content, headers=headers,
+            token_source=token_source)
 
     def call_sub_orchestrator(self,
                               name: str, input_: Optional[Any] = None,
diff --git a/azure/durable_functions/models/DurableOrchestrationStatus.py b/azure/durable_functions/models/DurableOrchestrationStatus.py
index b4990c9a..e60850f5 100644
--- a/azure/durable_functions/models/DurableOrchestrationStatus.py
+++ b/azure/durable_functions/models/DurableOrchestrationStatus.py
@@ -2,7 +2,6 @@
 from dateutil.parser import parse as dt_parse
 from typing import Any, List, Dict, Optional, Union
 
-from .OrchestrationRuntimeStatus import OrchestrationRuntimeStatus
 from .utils.json_utils import add_attrib, add_datetime_attrib
 
 
@@ -21,7 +20,8 @@ def __init__(self, name: Optional[str] = None, instanceId: Optional[str] = None,
                  **kwargs):
         self._name: Optional[str] = name
         self._instance_id: Optional[str] = instanceId
-        self._created_time: Optional[datetime] = dt_parse(createdTime) if createdTime is not None else None
+        self._created_time: Optional[datetime] = \
+            dt_parse(createdTime) if createdTime is not None else None
         self._last_updated_time: Optional[datetime] = dt_parse(lastUpdatedTime) \
             if lastUpdatedTime is not None else None
         self._input: Any = input
diff --git a/azure/durable_functions/models/PurgeHistoryResult.py b/azure/durable_functions/models/PurgeHistoryResult.py
index 4ccd48d0..b3d6587a 100644
--- a/azure/durable_functions/models/PurgeHistoryResult.py
+++ b/azure/durable_functions/models/PurgeHistoryResult.py
@@ -1,4 +1,4 @@
-from typing import Union, Dict, Any
+from typing import Dict, Any
 
 
 class PurgeHistoryResult:
diff --git a/azure/durable_functions/models/RetryOptions.py b/azure/durable_functions/models/RetryOptions.py
index 1770293c..95734ed4 100644
--- a/azure/durable_functions/models/RetryOptions.py
+++ b/azure/durable_functions/models/RetryOptions.py
@@ -1,4 +1,4 @@
-from typing import Any, Dict, Union
+from typing import Dict, Union
 
 from .utils.json_utils import add_attrib
 
diff --git a/azure/durable_functions/models/RpcManagementOptions.py b/azure/durable_functions/models/RpcManagementOptions.py
index 9fcc09e0..36158315 100644
--- a/azure/durable_functions/models/RpcManagementOptions.py
+++ b/azure/durable_functions/models/RpcManagementOptions.py
@@ -41,7 +41,7 @@ def to_url(self, base_url: Optional[str]) -> str:
         ----------
         base_url: str
             The base url to prepend to the url path
-        
+
         Raises
         ------
         ValueError
diff --git a/azure/durable_functions/models/TokenSource.py b/azure/durable_functions/models/TokenSource.py
index 375b84bd..d6ced05f 100644
--- a/azure/durable_functions/models/TokenSource.py
+++ b/azure/durable_functions/models/TokenSource.py
@@ -1,5 +1,5 @@
 from abc import ABC
-from typing import Dict, Any, Union
+from typing import Dict, Union
 
 from azure.durable_functions.models.utils.json_utils import add_attrib
 
diff --git a/azure/durable_functions/models/actions/CallActivityAction.py b/azure/durable_functions/models/actions/CallActivityAction.py
index 37361832..2e5c4ade 100644
--- a/azure/durable_functions/models/actions/CallActivityAction.py
+++ b/azure/durable_functions/models/actions/CallActivityAction.py
@@ -1,4 +1,4 @@
-from typing import Any, Dict, Union
+from typing import Dict, Union
 
 from .Action import Action
 from .ActionType import ActionType
diff --git a/azure/durable_functions/models/actions/CallActivityWithRetryAction.py b/azure/durable_functions/models/actions/CallActivityWithRetryAction.py
index 72fdba46..7ec97580 100644
--- a/azure/durable_functions/models/actions/CallActivityWithRetryAction.py
+++ b/azure/durable_functions/models/actions/CallActivityWithRetryAction.py
@@ -1,4 +1,4 @@
-from typing import Any, Dict, Union
+from typing import Dict, Union
 
 from .Action import Action
 from .ActionType import ActionType
diff --git a/azure/durable_functions/models/actions/ContinueAsNewAction.py b/azure/durable_functions/models/actions/ContinueAsNewAction.py
index eed20d52..76e49f6e 100644
--- a/azure/durable_functions/models/actions/ContinueAsNewAction.py
+++ b/azure/durable_functions/models/actions/ContinueAsNewAction.py
@@ -1,4 +1,4 @@
-from typing import Any, Dict, Union
+from typing import Dict, Union
 
 from .Action import Action
 from .ActionType import ActionType

From 5e188880c21d4401278a65fa41163f7aa37edea8 Mon Sep 17 00:00:00 2001
From: David Justo <david.justo.1996@gmail.com>
Date: Thu, 16 Jul 2020 20:55:37 -0700
Subject: [PATCH 03/13] undoing sample changes

---
 samples/function_chaining/DurableTrigger/__init__.py | 3 +--
 samples/function_chaining/local.settings.json        | 2 +-
 2 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/samples/function_chaining/DurableTrigger/__init__.py b/samples/function_chaining/DurableTrigger/__init__.py
index d3ceaed7..e4eccba6 100755
--- a/samples/function_chaining/DurableTrigger/__init__.py
+++ b/samples/function_chaining/DurableTrigger/__init__.py
@@ -27,5 +27,4 @@ async def main(req: func.HttpRequest, starter: str, message):
     client = DurableOrchestrationClient(starter)
     instance_id = await client.start_new(function_name)
     response = client.create_check_status_response(req, instance_id)
-    var = client.create_http_management_payload(instance_id)
-    message.set(str(var))
+    message.set(response)
diff --git a/samples/function_chaining/local.settings.json b/samples/function_chaining/local.settings.json
index a2ded917..853a5a84 100644
--- a/samples/function_chaining/local.settings.json
+++ b/samples/function_chaining/local.settings.json
@@ -1,7 +1,7 @@
 {
   "IsEncrypted": false,
   "Values": {
-    "AzureWebJobsStorage": "UseDevelopmentStorage=true",
+    "AzureWebJobsStorage": "",
     "FUNCTIONS_WORKER_RUNTIME": "python"
   }
 }

From f43a2329060da03c3eface1bd28ff8fbd397cd5f Mon Sep 17 00:00:00 2001
From: David Justo <david.justo.1996@gmail.com>
Date: Thu, 16 Jul 2020 20:55:53 -0700
Subject: [PATCH 04/13] added mypy to build

---
 noxfile.py | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/noxfile.py b/noxfile.py
index a6c9770b..25632006 100644
--- a/noxfile.py
+++ b/noxfile.py
@@ -1,6 +1,6 @@
 import nox
 
-@nox.session(python="3.7")
+@nox.session(python=["3.7","3.8"])
 def tests(session):
     # same as pip install -r -requirements.txt
     session.install("-r", "requirements.txt")
@@ -8,8 +8,13 @@ def tests(session):
     session.run("pytest", "-v", "tests")
 
 
-@nox.session(python="3.7")
+@nox.session(python=["3.7", "3.8"])
 def lint(session):
     session.install("flake8")
     session.install("flake8-docstrings")
     session.run("flake8", "./azure/")
+
+@nox.session(python=["3.7", "3.8"])
+def typecheck(session):
+    session.install("mypy")
+    session.run("mypy", "./azure/")
\ No newline at end of file

From e17c03c52c04db11c3ac0a3d4477eba4b7365962 Mon Sep 17 00:00:00 2001
From: David Justo <david.justo.1996@gmail.com>
Date: Thu, 16 Jul 2020 21:44:01 -0700
Subject: [PATCH 05/13] added type alias for being SerializableToJSON

---
 .../models/DurableOrchestrationClient.py      | 76 +++++++++++--------
 .../models/utils/type_aliases.py              |  4 +
 2 files changed, 50 insertions(+), 30 deletions(-)
 create mode 100644 azure/durable_functions/models/utils/type_aliases.py

diff --git a/azure/durable_functions/models/DurableOrchestrationClient.py b/azure/durable_functions/models/DurableOrchestrationClient.py
index 2a9b6640..b3ab85e4 100644
--- a/azure/durable_functions/models/DurableOrchestrationClient.py
+++ b/azure/durable_functions/models/DurableOrchestrationClient.py
@@ -1,6 +1,6 @@
 import json
 from datetime import datetime
-from typing import List, Any, Optional, Dict
+from typing import List, Any, Optional, Dict, Union
 from time import time
 from asyncio import sleep
 from urllib.parse import urlparse, quote
@@ -13,6 +13,7 @@
 from .OrchestrationRuntimeStatus import OrchestrationRuntimeStatus
 from ..models.DurableOrchestrationBindings import DurableOrchestrationBindings
 from .utils.http_utils import get_async_request, post_async_request, delete_async_request
+from .utils.type_aliases import SerializableToJSON
 from azure.functions._durable_functions import _serialize_custom_object
 
 
@@ -45,7 +46,7 @@ def __init__(self, context: str):
     async def start_new(self,
                         orchestration_function_name: str,
                         instance_id: Optional[str] = None,
-                        client_input: object = None) -> str:
+                        client_input: Optional[SerializableToJSON] = None) -> str:
         """Start a new instance of the specified orchestrator function.
 
         If an orchestration instance with the specified ID already exists, the
@@ -55,10 +56,10 @@ async def start_new(self,
         ----------
         orchestration_function_name : str
             The name of the orchestrator function to start.
-        instance_id : str
+        instance_id : Optional[str]
             The ID to use for the new orchestration instance. If no instance id is specified,
             the Durable Functions extension will generate a random GUID (recommended).
-        client_input : object
+        client_input : Optional[Any]
             JSON-serializable input value for the orchestrator function.
 
         Returns
@@ -69,7 +70,7 @@ async def start_new(self,
         request_url = self._get_start_new_url(
             instance_id=instance_id, orchestration_function_name=orchestration_function_name)
 
-        response: List[Any] = await self._post_async_request(
+        response: List[SerializableToJSON] = await self._post_async_request(
             request_url, self._get_json_input(client_input))
 
         status_code: int = response[0]
@@ -83,10 +84,10 @@ async def start_new(self,
         else:
             # Catch all: simply surfacing the durable-extension exception
             # we surface the stack trace too, since this may be a more involed exception
-            ex_message: Any = response[1]
+            ex_message: SerializableToJSON = response[1]
             raise Exception(ex_message)
 
-    def create_check_status_response(self, request, instance_id):
+    def create_check_status_response(self, request: func.HttpRequest, instance_id: str) -> func.HttpResponse:
         """Create a HttpResponse that contains useful information for \
         checking the status of the specified instance.
 
@@ -115,7 +116,8 @@ def create_check_status_response(self, request, instance_id):
         }
         return func.HttpResponse(**response_args)
 
-    def get_client_response_links(self, request, instance_id):
+    def get_client_response_links(self, 
+            request: func.HttpRequest, instance_id: str) -> Dict[str, str]:
         """Create a dictionary of orchestrator management urls.
 
         Parameters
@@ -127,7 +129,7 @@ def get_client_response_links(self, request, instance_id):
 
         Returns
         -------
-        dict
+        Dict[str, str]
             a dictionary object of orchestrator instance management urls
         """
         payload = self._orchestration_bindings.management_urls.copy()
@@ -140,8 +142,9 @@ def get_client_response_links(self, request, instance_id):
 
         return payload
 
-    async def raise_event(self, instance_id, event_name, event_data=None,
-                          task_hub_name=None, connection_name=None):
+    async def raise_event(self, instance_id: str, 
+            event_name: str, event_data: SerializableToJSON = None,
+            task_hub_name: str = None, connection_name: str = None) -> None:
         """Send an event notification message to a waiting orchestration instance.
 
         In order to handle the event, the target orchestration instance must be
@@ -153,7 +156,7 @@ async def raise_event(self, instance_id, event_name, event_data=None,
             The ID of the orchestration instance that will handle the event.
         event_name : str
             The name of the event.
-        event_data : any, optional
+        event_data : Any, optional
             The JSON-serializable data associated with the event.
         task_hub_name : str, optional
             The TaskHubName of the orchestration that will handle the event.
@@ -167,7 +170,7 @@ async def raise_event(self, instance_id, event_name, event_data=None,
         Exception
             Raises an exception if the status code is 404 or 400 when raising the event.
         """
-        if not event_name:
+        if event_name == "":
             raise ValueError("event_name must be a valid string.")
 
         request_url = self._get_raise_event_url(
@@ -187,9 +190,9 @@ async def raise_event(self, instance_id, event_name, event_data=None,
         if error_message:
             raise Exception(error_message)
 
-    async def get_status(self, instance_id: str, show_history: bool = None,
-                         show_history_output: bool = None,
-                         show_input: bool = None) -> DurableOrchestrationStatus:
+    async def get_status(self, instance_id: str, show_history: bool = False,
+                         show_history_output: bool = False,
+                         show_input: bool = False) -> DurableOrchestrationStatus:
         """Get the status of the specified orchestration instance.
 
         Parameters
@@ -252,7 +255,7 @@ async def get_status_all(self) -> List[DurableOrchestrationStatus]:
         if error_message:
             raise Exception(error_message)
         else:
-            statuses: List[Any] = response[1]
+            statuses: List[SerializableToJSON] = response[1]
             return [DurableOrchestrationStatus.from_json(o) for o in statuses]
 
     async def get_status_by(self, created_time_from: datetime = None,
@@ -276,6 +279,7 @@ async def get_status_by(self, created_time_from: datetime = None,
         DurableOrchestrationStatus
             The status of the requested orchestration instances
         """
+        # TODO: do we really want folks to us this without specifying all the args?
         options = RpcManagementOptions(created_time_from=created_time_from,
                                        created_time_to=created_time_to,
                                        runtime_status=runtime_status)
@@ -311,19 +315,20 @@ async def purge_instance_history(self, instance_id: str) -> PurgeHistoryResult:
         response = await self._delete_async_request(request_url)
         return self._parse_purge_instance_history_response(response)
 
-    async def purge_instance_history_by(self, created_time_from: datetime = None,
-                                        created_time_to: datetime = None,
-                                        runtime_status: List[OrchestrationRuntimeStatus] = None) \
+    async def purge_instance_history_by(
+            self, created_time_from: Optional[datetime] = None,
+            created_time_to: Optional[datetime] = None,
+            runtime_status: Optional[List[OrchestrationRuntimeStatus]] = None) \
             -> PurgeHistoryResult:
         """Delete the history of all orchestration instances that match the specified conditions.
 
         Parameters
         ----------
-        created_time_from : datetime
+        created_time_from : Optional[datetime]
             Delete orchestration history which were created after this Date.
-        created_time_to: datetime
+        created_time_to: Optional[datetime]
             Delete orchestration history which were created before this Date.
-        runtime_status: List[OrchestrationRuntimeStatus]
+        runtime_status: Optional[List[OrchestrationRuntimeStatus]]
             Delete orchestration instances which match any of the runtimeStatus values
             in this list.
 
@@ -332,6 +337,7 @@ async def purge_instance_history_by(self, created_time_from: datetime = None,
         PurgeHistoryResult
             The results of the request to purge history
         """
+        # TODO: do we really want folks to us this without specifying all the args?
         options = RpcManagementOptions(created_time_from=created_time_from,
                                        created_time_to=created_time_to,
                                        runtime_status=runtime_status)
@@ -339,7 +345,7 @@ async def purge_instance_history_by(self, created_time_from: datetime = None,
         response = await self._delete_async_request(request_url)
         return self._parse_purge_instance_history_response(response)
 
-    async def terminate(self, instance_id: str, reason: str):
+    async def terminate(self, instance_id: str, reason: str) -> None:
         """Terminate the specified orchestration instance.
 
         Parameters
@@ -348,6 +354,11 @@ async def terminate(self, instance_id: str, reason: str):
             The ID of the orchestration instance to query.
         reason: str
             The reason for terminating the instance.
+        
+        Raises
+        ------
+        Exception:
+            When the terminate call failed with an unexpected status code
 
         Returns
         -------
@@ -431,7 +442,8 @@ async def wait_for_completion_or_create_check_status_response(
                 return self.create_check_status_response(request, instance_id)
 
     @staticmethod
-    def _create_http_response(status_code: int, body: Any) -> func.HttpResponse:
+    def _create_http_response(
+            status_code: int, body: Union[str, SerializableToJSON]) -> func.HttpResponse:
         body_as_json = body if isinstance(body, str) else json.dumps(body)
         response_args = {
             "status_code": status_code,
@@ -469,7 +481,7 @@ def _get_json_input(client_input: object) -> Optional[str]:
         return None
 
     @staticmethod
-    def _replace_url_origin(request_url, value_url):
+    def _replace_url_origin(request_url: str, value_url: str) -> str:
         request_parsed_url = urlparse(request_url)
         value_parsed_url = urlparse(value_url)
         request_url_origin = '{url.scheme}://{url.netloc}/'.format(url=request_parsed_url)
@@ -478,7 +490,8 @@ def _replace_url_origin(request_url, value_url):
         return value_url
 
     @staticmethod
-    def _parse_purge_instance_history_response(response: List[Any]):
+    def _parse_purge_instance_history_response(
+            response: List[Any]) -> PurgeHistoryResult:
         switch_statement = {
             200: lambda: PurgeHistoryResult.from_json(response[1]),  # instance completed
             404: lambda: PurgeHistoryResult(instancesDeleted=0),  # instance not found
@@ -493,17 +506,20 @@ def _parse_purge_instance_history_response(response: List[Any]):
         else:
             raise Exception(result)
 
-    def _get_start_new_url(self, instance_id, orchestration_function_name):
+    def _get_start_new_url(self, 
+            instance_id: Optional[str], orchestration_function_name: str) -> str:
         instance_path = f'/{instance_id}' if instance_id is not None else ''
         request_url = f'{self._orchestration_bindings.rpc_base_url}orchestrators/' \
                       f'{orchestration_function_name}{instance_path}'
         return request_url
 
-    def _get_raise_event_url(self, instance_id, event_name, task_hub_name, connection_name):
+    def _get_raise_event_url(self, 
+            instance_id: str, event_name: str, 
+            task_hub_name: Optional[str], connection_name: Optional[str]) -> str:
         request_url = f'{self._orchestration_bindings.rpc_base_url}' \
                       f'instances/{instance_id}/raiseEvent/{event_name}'
 
-        query = []
+        query: List[str] = []
         if task_hub_name:
             query.append(f'taskHub={task_hub_name}')
 
diff --git a/azure/durable_functions/models/utils/type_aliases.py b/azure/durable_functions/models/utils/type_aliases.py
new file mode 100644
index 00000000..031c2e59
--- /dev/null
+++ b/azure/durable_functions/models/utils/type_aliases.py
@@ -0,0 +1,4 @@
+from typing import Any
+
+# TODO: Use Python's NewType functionality to further constraint types
+SerializableToJSON = Any

From 17c99eeafeb3723f728125e65a0bea2a3588ca2d Mon Sep 17 00:00:00 2001
From: David Justo <david.justo.1996@gmail.com>
Date: Thu, 16 Jul 2020 21:51:53 -0700
Subject: [PATCH 06/13] lint

---
 .../models/DurableOrchestrationClient.py      | 21 ++++++++++---------
 1 file changed, 11 insertions(+), 10 deletions(-)

diff --git a/azure/durable_functions/models/DurableOrchestrationClient.py b/azure/durable_functions/models/DurableOrchestrationClient.py
index b3ab85e4..15f7f1cf 100644
--- a/azure/durable_functions/models/DurableOrchestrationClient.py
+++ b/azure/durable_functions/models/DurableOrchestrationClient.py
@@ -87,7 +87,8 @@ async def start_new(self,
             ex_message: SerializableToJSON = response[1]
             raise Exception(ex_message)
 
-    def create_check_status_response(self, request: func.HttpRequest, instance_id: str) -> func.HttpResponse:
+    def create_check_status_response(
+            self, request: func.HttpRequest, instance_id: str) -> func.HttpResponse:
         """Create a HttpResponse that contains useful information for \
         checking the status of the specified instance.
 
@@ -116,8 +117,8 @@ def create_check_status_response(self, request: func.HttpRequest, instance_id: s
         }
         return func.HttpResponse(**response_args)
 
-    def get_client_response_links(self, 
-            request: func.HttpRequest, instance_id: str) -> Dict[str, str]:
+    def get_client_response_links(
+            self, request: func.HttpRequest, instance_id: str) -> Dict[str, str]:
         """Create a dictionary of orchestrator management urls.
 
         Parameters
@@ -142,8 +143,8 @@ def get_client_response_links(self,
 
         return payload
 
-    async def raise_event(self, instance_id: str, 
-            event_name: str, event_data: SerializableToJSON = None,
+    async def raise_event(
+            self, instance_id: str, event_name: str, event_data: SerializableToJSON = None,
             task_hub_name: str = None, connection_name: str = None) -> None:
         """Send an event notification message to a waiting orchestration instance.
 
@@ -354,7 +355,7 @@ async def terminate(self, instance_id: str, reason: str) -> None:
             The ID of the orchestration instance to query.
         reason: str
             The reason for terminating the instance.
-        
+
         Raises
         ------
         Exception:
@@ -506,15 +507,15 @@ def _parse_purge_instance_history_response(
         else:
             raise Exception(result)
 
-    def _get_start_new_url(self, 
-            instance_id: Optional[str], orchestration_function_name: str) -> str:
+    def _get_start_new_url(
+            self, instance_id: Optional[str], orchestration_function_name: str) -> str:
         instance_path = f'/{instance_id}' if instance_id is not None else ''
         request_url = f'{self._orchestration_bindings.rpc_base_url}orchestrators/' \
                       f'{orchestration_function_name}{instance_path}'
         return request_url
 
-    def _get_raise_event_url(self, 
-            instance_id: str, event_name: str, 
+    def _get_raise_event_url(
+            self, instance_id: str, event_name: str,
             task_hub_name: Optional[str], connection_name: Optional[str]) -> str:
         request_url = f'{self._orchestration_bindings.rpc_base_url}' \
                       f'instances/{instance_id}/raiseEvent/{event_name}'

From a0686e39baa5e10ca9023093cbdb4ab54196027f Mon Sep 17 00:00:00 2001
From: David Justo <david.justo.1996@gmail.com>
Date: Tue, 28 Jul 2020 18:46:54 -0700
Subject: [PATCH 07/13] after merge, made everything typecheck

---
 .../models/DurableOrchestrationClient.py      |  3 +-
 .../models/DurableOrchestrationContext.py     | 98 ++++++++++++++-----
 .../actions/CallSubOrchestratorAction.py      |  5 +-
 .../CallSubOrchestratorWithRetryAction.py     |  4 +-
 .../models/actions/CreateTimerAction.py       |  7 +-
 .../tasks/call_suborchestrator.py             |  2 +-
 .../tasks/call_suborchestrator_with_retry.py  |  2 +-
 .../durable_functions/tasks/task_utilities.py | 38 +++----
 8 files changed, 109 insertions(+), 50 deletions(-)

diff --git a/azure/durable_functions/models/DurableOrchestrationClient.py b/azure/durable_functions/models/DurableOrchestrationClient.py
index 2363e92c..de170b09 100644
--- a/azure/durable_functions/models/DurableOrchestrationClient.py
+++ b/azure/durable_functions/models/DurableOrchestrationClient.py
@@ -152,8 +152,7 @@ def get_client_response_links(
         payload = self._orchestration_bindings.management_urls.copy()
 
         for key, _ in payload.items():
-            request_is_not_none = not (request is None)
-            if request_is_not_none and request.url:
+            if not(request is None) and request.url:
                 payload[key] = self._replace_url_origin(request.url, payload[key])
             payload[key] = payload[key].replace(
                 self._orchestration_bindings.management_urls["id"], instance_id)
diff --git a/azure/durable_functions/models/DurableOrchestrationContext.py b/azure/durable_functions/models/DurableOrchestrationContext.py
index 7fd35915..e93aecdb 100644
--- a/azure/durable_functions/models/DurableOrchestrationContext.py
+++ b/azure/durable_functions/models/DurableOrchestrationContext.py
@@ -33,26 +33,8 @@ def __init__(self,
         self._custom_status: Any = None
         self._new_uuid_counter: int = 0
         self._sub_orchestrator_counter: int = 0
-        self.call_sub_orchestrator = \
-            lambda n, i=None, _id=None: call_sub_orchestrator_task(
-                context=self,
-                state=self.histories,
-                name=n,
-                input_=i,
-                instance_id=_id)
-        self.call_sub_orchestrator_with_retry = \
-            lambda n, o, i=None, _id=None: call_sub_orchestrator_with_retry_task(
-                context=self,
-                state=self.histories,
-                retry_options=o,
-                name=n,
-                input_=i,
-                instance_id=_id)
-        self.wait_for_external_event = lambda n: wait_for_external_event_task(
-            state=self.histories,
-            name=n)
+        # TODO: waiting on the `continue_as_new` intellisense until that's implemented
         self.continue_as_new = lambda i: continue_as_new(input_=i)
-        self.create_timer = lambda d: create_timer_task(state=self.histories, fire_at=d)
         self.decision_started_event: HistoryEvent = \
             [e_ for e_ in self.histories
              if e_.event_type == HistoryEventType.ORCHESTRATOR_STARTED][0]
@@ -163,7 +145,7 @@ def call_http(self, method: str, uri: str, content: Optional[str] = None,
     def call_sub_orchestrator(self,
                               name: str, input_: Optional[Any] = None,
                               instance_id: Optional[str] = None) -> Task:
-        """Schedule an orchestration function named `name` for execution.
+        """Schedule sub-orchestration function named `name` for execution.
 
         Parameters
         ----------
@@ -172,11 +154,49 @@ def call_sub_orchestrator(self,
         input_: Optional[Any]
             The JSON-serializable input to pass to the orchestrator function.
         instance_id: Optional[str]
-            A unique ID to use for the sub-orchestration instance. If `instanceId` is not
-            specified, the extension will generate an id in the format `<calling orchestrator
-            instance ID>:<#>`
+            A unique ID to use for the sub-orchestration instance.
+
+        Returns
+        -------
+        Task
+            A Durable Task that completes when the called sub-orchestrator completes or fails.
         """
-        raise NotImplementedError("This is a placeholder.")
+        return call_sub_orchestrator_task(
+            context=self,
+            state=self.histories,
+            name=name,
+            input_=input_,
+            instance_id=instance_id)
+
+    def call_sub_orchestrator_with_retry(self,
+                                         name: str, retry_options: RetryOptions,
+                                         input_: Optional[Any] = None,
+                                         instance_id: Optional[str] = None) -> Task:
+        """Schedule sub-orchestration function named `name` for execution, with retry-options.
+
+        Parameters
+        ----------
+        name: str
+            The name of the activity function to schedule.
+        retry_options: RetryOptions
+            The settings for retrying this sub-orchestrator in case of a failure.
+        input_: Optional[Any]
+            The JSON-serializable input to pass to the activity function. Defaults to None.
+        instance_id: str
+            The instance ID of the sub-orchestrator to call.
+
+        Returns
+        -------
+        Task
+            A Durable Task that completes when the called sub-orchestrator completes or fails.
+        """
+        return call_sub_orchestrator_with_retry_task(
+            context=self,
+            state=self.histories,
+            retry_options=retry_options,
+            name=name,
+            input_=input_,
+            instance_id=instance_id)
 
     def get_input(self) -> Optional[Any]:
         """Get the orchestration input."""
@@ -338,3 +358,33 @@ def function_context(self) -> FunctionContext:
             Object containing function level attributes not used by durable orchestrator.
         """
         return self._function_context
+
+    def create_timer(self, fire_at: datetime.datetime) -> Task:
+        """Create a Durable Timer Task to implement a deadline at which to wake-up the orchestrator.
+
+        Parameters
+        ----------
+        fire_at : datetime.datetime
+            The time for the timer to trigger
+
+        Returns
+        -------
+        TimerTask
+            A Durable Timer Task that schedules the timer to wake up the activity
+        """
+        return create_timer_task(state=self.histories, fire_at=fire_at)
+
+    def wait_for_external_event(self, name: str) -> Task:
+        """Wait asynchronously for an event to be raised with the name `name`.
+
+        Parameters
+        ----------
+        name : str
+            The event name of the event that the task is waiting for.
+
+        Returns
+        -------
+        Task
+            Task to wait for the event
+        """
+        return wait_for_external_event_task(state=self.histories, name=name)
diff --git a/azure/durable_functions/models/actions/CallSubOrchestratorAction.py b/azure/durable_functions/models/actions/CallSubOrchestratorAction.py
index 5a733716..16b4c853 100644
--- a/azure/durable_functions/models/actions/CallSubOrchestratorAction.py
+++ b/azure/durable_functions/models/actions/CallSubOrchestratorAction.py
@@ -10,10 +10,11 @@
 class CallSubOrchestratorAction(Action):
     """Defines the structure of the Call SubOrchestrator object."""
 
-    def __init__(self, function_name: str, _input: Optional[Any] = None, instance_id: str = ""):
+    def __init__(self, function_name: str, _input: Optional[Any] = None,
+                 instance_id: Optional[str] = None):
         self.function_name: str = function_name
         self._input: str = dumps(_input, default=_serialize_custom_object)
-        self.instance_id: str = instance_id
+        self.instance_id: Optional[str] = instance_id
 
         if not self.function_name:
             raise ValueError("function_name cannot be empty")
diff --git a/azure/durable_functions/models/actions/CallSubOrchestratorWithRetryAction.py b/azure/durable_functions/models/actions/CallSubOrchestratorWithRetryAction.py
index dc77b454..07b0ba55 100644
--- a/azure/durable_functions/models/actions/CallSubOrchestratorWithRetryAction.py
+++ b/azure/durable_functions/models/actions/CallSubOrchestratorWithRetryAction.py
@@ -13,11 +13,11 @@ class CallSubOrchestratorWithRetryAction(Action):
 
     def __init__(self, function_name: str, retry_options: RetryOptions,
                  _input: Optional[Any] = None,
-                 instance_id: str = ""):
+                 instance_id: Optional[str] = None):
         self.function_name: str = function_name
         self._input: str = dumps(_input, default=_serialize_custom_object)
         self.retry_options: RetryOptions = retry_options
-        self.instance_id: str = instance_id
+        self.instance_id: Optional[str] = instance_id
 
         if not self.function_name:
             raise ValueError("function_name cannot be empty")
diff --git a/azure/durable_functions/models/actions/CreateTimerAction.py b/azure/durable_functions/models/actions/CreateTimerAction.py
index d50baf8e..40251f7e 100644
--- a/azure/durable_functions/models/actions/CreateTimerAction.py
+++ b/azure/durable_functions/models/actions/CreateTimerAction.py
@@ -20,7 +20,7 @@ class CreateTimerAction(Action):
     """
 
     def __init__(self, fire_at: datetime.datetime, is_cancelled: bool = False):
-        self.action_type: ActionType = ActionType.CREATE_TIMER
+        self._action_type: ActionType = ActionType.CREATE_TIMER
         self.fire_at: datetime.datetime = fire_at
         self.is_cancelled: bool = is_cancelled
 
@@ -41,3 +41,8 @@ def to_json(self) -> Dict[str, Any]:
         add_datetime_attrib(json_dict, self, 'fire_at', 'fireAt')
         add_attrib(json_dict, self, 'is_cancelled', 'isCanceled')
         return json_dict
+
+    @property
+    def action_type(self) -> int:
+        """Get the type of action this class represents."""
+        return ActionType.CREATE_TIMER
diff --git a/azure/durable_functions/tasks/call_suborchestrator.py b/azure/durable_functions/tasks/call_suborchestrator.py
index f17ee28e..851ea25c 100644
--- a/azure/durable_functions/tasks/call_suborchestrator.py
+++ b/azure/durable_functions/tasks/call_suborchestrator.py
@@ -14,7 +14,7 @@ def call_sub_orchestrator_task(
         state: List[HistoryEvent],
         name: str,
         input_: Optional[Any] = None,
-        instance_id: str = "") -> Task:
+        instance_id: Optional[str] = None) -> Task:
     """Determine the state of Scheduling a sub-orchestrator for execution.
 
     Parameters
diff --git a/azure/durable_functions/tasks/call_suborchestrator_with_retry.py b/azure/durable_functions/tasks/call_suborchestrator_with_retry.py
index e1f2766b..3be2fa65 100644
--- a/azure/durable_functions/tasks/call_suborchestrator_with_retry.py
+++ b/azure/durable_functions/tasks/call_suborchestrator_with_retry.py
@@ -16,7 +16,7 @@ def call_sub_orchestrator_with_retry_task(
         retry_options: RetryOptions,
         name: str,
         input_: Optional[Any] = None,
-        instance_id: str = "") -> Task:
+        instance_id: Optional[str] = None) -> Task:
     """Determine the state of Scheduling a sub-orchestrator for execution, with retry options.
 
     Parameters
diff --git a/azure/durable_functions/tasks/task_utilities.py b/azure/durable_functions/tasks/task_utilities.py
index 167a31d5..99a8d4b5 100644
--- a/azure/durable_functions/tasks/task_utilities.py
+++ b/azure/durable_functions/tasks/task_utilities.py
@@ -199,7 +199,7 @@ def set_processed(tasks):
 
 
 def find_sub_orchestration(
-        state: List[HistoryEventType],
+        state: List[HistoryEvent],
         event_type: HistoryEventType,
         name: Optional[str] = None,
         context=None,
@@ -209,11 +209,11 @@ def find_sub_orchestration(
 
     Parameters
     ----------
-    state: List[HistoryEventType]
+    state: List[HistoryEvent]
         The history of Durable events
     event_type: HistoryEventType
         The type of Durable event to look for.
-    name: str:
+    name: Optional[str]:
         Name of the sub-orchestrator.
     context: Optional['DurableOrchestrationContext']
         A reference to the orchestration context
@@ -246,30 +246,35 @@ def gen_err_message(counter: int, mid_message: str, found: str, expected: str) -
         context._sub_orchestrator_counter += 1
         counter: int = context._sub_orchestrator_counter
 
+        if name is None:
+            err = "Tried to lookup suborchestration in history but had not name to reference it."
+            raise ValueError(err)
+
         # TODO: The HistoryEvent does not necessarily have an name or an instance_id
         #       We should create sub-classes of these types like JS does
+        err_message: str = ""
         if not(event.Name == name):
             mid_message = "a function name of {} instead of the provided function name of {}."
-            err_message: str = gen_err_message(counter, mid_message, event.name, name)
+            err_message = gen_err_message(counter, mid_message, event.Name, name)
             raise ValueError(err_message)
         if instance_id and not(event.InstanceId == instance_id):
             mid_message = "an instance id of {} instead of the provided instance id of {}."
-            err_message: str = gen_err_message(counter, mid_message, event.name, name)
+            err_message = gen_err_message(counter, mid_message, event.Name, name)
             raise ValueError(err_message)
 
     return event
 
 
 def find_sub_orchestration_created(
-        state: List[HistoryEventType],
+        state: List[HistoryEvent],
         name: str,
         context=None,
-        instance_id: Optional[str] = None) -> Optional[HistoryEventType]:
+        instance_id: Optional[str] = None) -> Optional[HistoryEvent]:
     """Look-up matching sub-orchestrator created event in the state array.
 
     Parameters
     ----------
-    state: List[HistoryEventType]:
+    state: List[HistoryEvent]:
         The history of Durable events
     name: str:
         Name of the sub-orchestrator.
@@ -285,7 +290,7 @@ def find_sub_orchestration_created(
 
     Returns
     -------
-    Optional[HistoryEventType]:
+    Optional[HistoryEvent]:
         The matching sub-orchestration creation event. Else, None.
     """
     event_type = HistoryEventType.SUB_ORCHESTRATION_INSTANCE_CREATED
@@ -298,20 +303,20 @@ def find_sub_orchestration_created(
 
 
 def find_sub_orchestration_completed(
-        state: List[HistoryEventType],
-        scheduled_task: Optional[HistoryEventType]) -> Optional[HistoryEventType]:
+        state: List[HistoryEvent],
+        scheduled_task: Optional[HistoryEvent]) -> Optional[HistoryEvent]:
     """Look-up the sub-orchestration completed event.
 
     Parameters
     ----------
-    state: List[HistoryEventType]:
+    state: List[HistoryEvent]:
         The history of Durable events
-    scheduled_task: Optional[HistoryEventType]:
+    scheduled_task: Optional[HistoryEvent]:
         The sub-orchestration creation event, if found.
 
     Returns
     -------
-    Optional[HistoryEventType]:
+    Optional[HistoryEvent]:
         The matching sub-orchestration completed event, if found. Else, None.
     """
     event_type = HistoryEventType.SUB_ORCHESTRATION_INSTANCE_COMPLETED
@@ -395,8 +400,7 @@ def should_preserve(event: HistoryEvent) -> bool:
     event: Optional[HistoryEvent] = None
 
     # Preverse only the elements of the state array that correspond with the looked-up event
-    matches = filter(should_preserve, state)
-    matches = list(matches)
+    matches = list(filter(should_preserve, state))
 
     if len(matches) >= 1:
         # TODO: in many instances, `matches` will be greater than 1 in length. We take the
@@ -404,5 +408,5 @@ def should_preserve(event: HistoryEvent) -> bool:
         # we assume corresponds to the one we are looking for. This may be brittle but
         # is true about other areas of the code as well such as with `call_activity`.
         # We should try to refactor this logic at some point
-        event: HistoryEventType = matches[0]
+        event = matches[0]
     return event

From 31c981cdf1054d11b0983d33332ba442f395c318 Mon Sep 17 00:00:00 2001
From: David Justo <david.justo.1996@gmail.com>
Date: Thu, 30 Jul 2020 16:20:54 -0700
Subject: [PATCH 08/13] PR feedback

---
 .../models/DurableOrchestrationBindings.py                  | 1 +
 .../durable_functions/models/DurableOrchestrationClient.py  | 2 +-
 azure/durable_functions/models/RpcManagementOptions.py      | 3 +--
 azure/durable_functions/tasks/new_uuid.py                   | 6 +++++-
 4 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/azure/durable_functions/models/DurableOrchestrationBindings.py b/azure/durable_functions/models/DurableOrchestrationBindings.py
index 00f613a5..9deb597d 100644
--- a/azure/durable_functions/models/DurableOrchestrationBindings.py
+++ b/azure/durable_functions/models/DurableOrchestrationBindings.py
@@ -17,6 +17,7 @@ def __init__(self, taskHubName: str, creationUrls: Dict[str, str],
         self._task_hub_name: str = taskHubName
         self._creation_urls: Dict[str, str] = creationUrls
         self._management_urls: Dict[str, str] = managementUrls
+        # TODO: we can remove this once we drop support for 1.x, this is always provided in 2.x
         self._rpc_base_url: Optional[str] = rpcBaseUrl
         self._client_data = FunctionContext(**kwargs)
 
diff --git a/azure/durable_functions/models/DurableOrchestrationClient.py b/azure/durable_functions/models/DurableOrchestrationClient.py
index de170b09..65c599ee 100644
--- a/azure/durable_functions/models/DurableOrchestrationClient.py
+++ b/azure/durable_functions/models/DurableOrchestrationClient.py
@@ -188,7 +188,7 @@ async def raise_event(
             Raises an exception if the status code is 404 or 400 when raising the event.
         """
         if event_name == "":
-            raise ValueError("event_name must be a valid string.")
+            raise ValueError("event_name must be a non-empty string.")
 
         request_url = self._get_raise_event_url(
             instance_id, event_name, task_hub_name, connection_name)
diff --git a/azure/durable_functions/models/RpcManagementOptions.py b/azure/durable_functions/models/RpcManagementOptions.py
index 36158315..c142a3a4 100644
--- a/azure/durable_functions/models/RpcManagementOptions.py
+++ b/azure/durable_functions/models/RpcManagementOptions.py
@@ -53,8 +53,7 @@ def to_url(self, base_url: Optional[str]) -> str:
             The Url used to get orchestration status information
         """
         if base_url is None:
-            # TODO: In JS we manage a "legacy app frontend code path. Here too?"
-            raise ValueError("orchestration bindings has not RPC base url")
+             raise ValueError("orchestration bindings has not RPC base url")
 
         url = f"{base_url}instances/{self._instance_id if self._instance_id else ''}"
 
diff --git a/azure/durable_functions/tasks/new_uuid.py b/azure/durable_functions/tasks/new_uuid.py
index 43140824..a5cab69d 100644
--- a/azure/durable_functions/tasks/new_uuid.py
+++ b/azure/durable_functions/tasks/new_uuid.py
@@ -1,6 +1,10 @@
 from uuid import uuid5, NAMESPACE_OID
 
 from azure.durable_functions.constants import DATETIME_STRING_FORMAT
+import typing
+
+if typing.TYPE_CHECKING:
+    from azure.durable_functions.models.DurableOrchestrationContext import DurableOrchestrationContext
 
 URL_NAMESPACE: str = "9e952958-5e33-4daf-827f-2fa12937b875"
 
@@ -10,7 +14,7 @@ def _create_deterministic_uuid(namespace_value: str, name: str) -> str:
     return str(uuid5(namespace_uuid, name))
 
 
-def new_uuid(context) -> str:
+def new_uuid(context: 'DurableOrchestrationContext') -> str:
     """Create a new UUID that is safe for replay within an orchestration or operation.
 
     The default implementation of this method creates a name-based UUID

From d3c64a533fbe03dd8f17bdd2f010826539d2ab7c Mon Sep 17 00:00:00 2001
From: David Justo <david.justo.1996@gmail.com>
Date: Thu, 30 Jul 2020 16:28:55 -0700
Subject: [PATCH 09/13] PR feedback 2

---
 azure/durable_functions/models/DurableOrchestrationStatus.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/azure/durable_functions/models/DurableOrchestrationStatus.py b/azure/durable_functions/models/DurableOrchestrationStatus.py
index e60850f5..2712069a 100644
--- a/azure/durable_functions/models/DurableOrchestrationStatus.py
+++ b/azure/durable_functions/models/DurableOrchestrationStatus.py
@@ -26,7 +26,7 @@ def __init__(self, name: Optional[str] = None, instanceId: Optional[str] = None,
             if lastUpdatedTime is not None else None
         self._input: Any = input
         self._output: Any = output
-        self._runtime_status: Optional[str] = runtimeStatus
+        self._runtime_status: Optional[str] = runtimeStatus # TODO: GH issue 178
         self._custom_status: Any = customStatus
         self._history: Optional[List[Any]] = history
         if kwargs is not None:

From 50470fd5dc62ec8f1ced5ff91fab9740c1ba99fa Mon Sep 17 00:00:00 2001
From: David Justo <david.justo.1996@gmail.com>
Date: Thu, 30 Jul 2020 16:33:06 -0700
Subject: [PATCH 10/13] linting fix

---
 azure/durable_functions/models/DurableOrchestrationStatus.py | 2 +-
 azure/durable_functions/models/RpcManagementOptions.py       | 2 +-
 azure/durable_functions/tasks/new_uuid.py                    | 3 ++-
 3 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/azure/durable_functions/models/DurableOrchestrationStatus.py b/azure/durable_functions/models/DurableOrchestrationStatus.py
index 2712069a..3dd20a51 100644
--- a/azure/durable_functions/models/DurableOrchestrationStatus.py
+++ b/azure/durable_functions/models/DurableOrchestrationStatus.py
@@ -26,7 +26,7 @@ def __init__(self, name: Optional[str] = None, instanceId: Optional[str] = None,
             if lastUpdatedTime is not None else None
         self._input: Any = input
         self._output: Any = output
-        self._runtime_status: Optional[str] = runtimeStatus # TODO: GH issue 178
+        self._runtime_status: Optional[str] = runtimeStatus  # TODO: GH issue 178
         self._custom_status: Any = customStatus
         self._history: Optional[List[Any]] = history
         if kwargs is not None:
diff --git a/azure/durable_functions/models/RpcManagementOptions.py b/azure/durable_functions/models/RpcManagementOptions.py
index c142a3a4..c16c508f 100644
--- a/azure/durable_functions/models/RpcManagementOptions.py
+++ b/azure/durable_functions/models/RpcManagementOptions.py
@@ -53,7 +53,7 @@ def to_url(self, base_url: Optional[str]) -> str:
             The Url used to get orchestration status information
         """
         if base_url is None:
-             raise ValueError("orchestration bindings has not RPC base url")
+            raise ValueError("orchestration bindings has not RPC base url")
 
         url = f"{base_url}instances/{self._instance_id if self._instance_id else ''}"
 
diff --git a/azure/durable_functions/tasks/new_uuid.py b/azure/durable_functions/tasks/new_uuid.py
index a5cab69d..364e4798 100644
--- a/azure/durable_functions/tasks/new_uuid.py
+++ b/azure/durable_functions/tasks/new_uuid.py
@@ -4,7 +4,8 @@
 import typing
 
 if typing.TYPE_CHECKING:
-    from azure.durable_functions.models.DurableOrchestrationContext import DurableOrchestrationContext
+    from azure.durable_functions.models.DurableOrchestrationContext \
+        import DurableOrchestrationContext
 
 URL_NAMESPACE: str = "9e952958-5e33-4daf-827f-2fa12937b875"
 

From a52b75388d4520c15219e81191e1efb373ad8a48 Mon Sep 17 00:00:00 2001
From: David Justo <david.justo.1996@gmail.com>
Date: Mon, 3 Aug 2020 10:44:01 -0700
Subject: [PATCH 11/13] removed SerializableToJSON 4 Any, may want to revisit
 the idea via typing Protocols later

---
 .../models/DurableOrchestrationClient.py            | 13 ++++++-------
 .../durable_functions/models/utils/type_aliases.py  |  4 ----
 2 files changed, 6 insertions(+), 11 deletions(-)
 delete mode 100644 azure/durable_functions/models/utils/type_aliases.py

diff --git a/azure/durable_functions/models/DurableOrchestrationClient.py b/azure/durable_functions/models/DurableOrchestrationClient.py
index 65c599ee..8bc22786 100644
--- a/azure/durable_functions/models/DurableOrchestrationClient.py
+++ b/azure/durable_functions/models/DurableOrchestrationClient.py
@@ -13,7 +13,6 @@
 from .OrchestrationRuntimeStatus import OrchestrationRuntimeStatus
 from ..models.DurableOrchestrationBindings import DurableOrchestrationBindings
 from .utils.http_utils import get_async_request, post_async_request, delete_async_request
-from .utils.type_aliases import SerializableToJSON
 from azure.functions._durable_functions import _serialize_custom_object
 
 
@@ -46,7 +45,7 @@ def __init__(self, context: str):
     async def start_new(self,
                         orchestration_function_name: str,
                         instance_id: Optional[str] = None,
-                        client_input: Optional[SerializableToJSON] = None) -> str:
+                        client_input: Optional[Any] = None) -> str:
         """Start a new instance of the specified orchestrator function.
 
         If an orchestration instance with the specified ID already exists, the
@@ -70,7 +69,7 @@ async def start_new(self,
         request_url = self._get_start_new_url(
             instance_id=instance_id, orchestration_function_name=orchestration_function_name)
 
-        response: List[SerializableToJSON] = await self._post_async_request(
+        response: List[Any] = await self._post_async_request(
             request_url, self._get_json_input(client_input))
 
         status_code: int = response[0]
@@ -84,7 +83,7 @@ async def start_new(self,
         else:
             # Catch all: simply surfacing the durable-extension exception
             # we surface the stack trace too, since this may be a more involed exception
-            ex_message: SerializableToJSON = response[1]
+            ex_message: Any = response[1]
             raise Exception(ex_message)
 
     def create_check_status_response(
@@ -160,7 +159,7 @@ def get_client_response_links(
         return payload
 
     async def raise_event(
-            self, instance_id: str, event_name: str, event_data: SerializableToJSON = None,
+            self, instance_id: str, event_name: str, event_data: Any = None,
             task_hub_name: str = None, connection_name: str = None) -> None:
         """Send an event notification message to a waiting orchestration instance.
 
@@ -272,7 +271,7 @@ async def get_status_all(self) -> List[DurableOrchestrationStatus]:
         if error_message:
             raise Exception(error_message)
         else:
-            statuses: List[SerializableToJSON] = response[1]
+            statuses: List[Any] = response[1]
             return [DurableOrchestrationStatus.from_json(o) for o in statuses]
 
     async def get_status_by(self, created_time_from: datetime = None,
@@ -460,7 +459,7 @@ async def wait_for_completion_or_create_check_status_response(
 
     @staticmethod
     def _create_http_response(
-            status_code: int, body: Union[str, SerializableToJSON]) -> func.HttpResponse:
+            status_code: int, body: Union[str, Any]) -> func.HttpResponse:
         body_as_json = body if isinstance(body, str) else json.dumps(body)
         response_args = {
             "status_code": status_code,
diff --git a/azure/durable_functions/models/utils/type_aliases.py b/azure/durable_functions/models/utils/type_aliases.py
deleted file mode 100644
index 031c2e59..00000000
--- a/azure/durable_functions/models/utils/type_aliases.py
+++ /dev/null
@@ -1,4 +0,0 @@
-from typing import Any
-
-# TODO: Use Python's NewType functionality to further constraint types
-SerializableToJSON = Any

From aae83c98f52120a8495d31aa52fa25a694f1c1af Mon Sep 17 00:00:00 2001
From: David Justo <david.justo.1996@gmail.com>
Date: Wed, 5 Aug 2020 09:28:56 -0700
Subject: [PATCH 12/13] ContinueAsNew works, needed to mark the orchestrator as
 completed (#158)

---
 .../models/DurableOrchestrationContext.py     |  8 +-
 azure/durable_functions/orchestrator.py       | 99 +++++++++++--------
 .../tasks/continue_as_new.py                  | 13 +--
 tests/orchestrator/test_continue_as_new.py    |  3 +-
 4 files changed, 69 insertions(+), 54 deletions(-)

diff --git a/azure/durable_functions/models/DurableOrchestrationContext.py b/azure/durable_functions/models/DurableOrchestrationContext.py
index b2656c0a..ec6b9197 100644
--- a/azure/durable_functions/models/DurableOrchestrationContext.py
+++ b/azure/durable_functions/models/DurableOrchestrationContext.py
@@ -32,6 +32,7 @@ def __init__(self,
         self._custom_status: Any = None
         self._new_uuid_counter: int = 0
         self._sub_orchestrator_counter: int = 0
+        self._continue_as_new_flag: bool = False
         self.call_activity = lambda n, i=None: call_activity_task(
             state=self.histories,
             name=n,
@@ -65,7 +66,7 @@ def __init__(self,
             state=self.histories,
             name=n)
         self.new_uuid = lambda: new_uuid(context=self)
-        self.continue_as_new = lambda i: continue_as_new(input_=i)
+        self.continue_as_new = lambda i: continue_as_new(context=self, input_=i)
         self.task_any = lambda t: task_any(tasks=t)
         self.task_all = lambda t: task_all(tasks=t)
         self.create_timer = lambda d: create_timer_task(state=self.histories, fire_at=d)
@@ -344,3 +345,8 @@ def function_context(self) -> FunctionContext:
             Object containing function level attributes not used by durable orchestrator.
         """
         return self._function_context
+
+    @property
+    def will_continue_as_new(self) -> bool:
+        """Return true if continue_as_new was called."""
+        return self._continue_as_new_flag
diff --git a/azure/durable_functions/orchestrator.py b/azure/durable_functions/orchestrator.py
index 74a6c20a..00abe940 100644
--- a/azure/durable_functions/orchestrator.py
+++ b/azure/durable_functions/orchestrator.py
@@ -49,57 +49,66 @@ def handle(self, context: DurableOrchestrationContext):
         suspended = False
 
         fn_output = self.fn(self.durable_context)
+
         # If `fn_output` is not an Iterator, then the orchestrator
         # function does not make use of its context parameter. If so,
         # `fn_output` is the return value instead of a generator
-        if isinstance(fn_output, Iterator):
-            self.generator = fn_output
-
-        else:
+        if not isinstance(fn_output, Iterator):
             orchestration_state = OrchestratorState(
                 is_done=True,
                 output=fn_output,
                 actions=self.durable_context.actions,
                 custom_status=self.durable_context.custom_status)
-            return orchestration_state.to_json_string()
-        try:
-            generation_state = self._generate_next(None)
-
-            while not suspended:
-                self._add_to_actions(generation_state)
-
-                if should_suspend(generation_state):
-                    orchestration_state = OrchestratorState(
-                        is_done=False,
-                        output=None,
-                        actions=self.durable_context.actions,
-                        custom_status=self.durable_context.custom_status)
-                    suspended = True
-                    continue
-
-                if (isinstance(generation_state, Task)
-                    or isinstance(generation_state, TaskSet)) and (
-                        generation_state.is_faulted):
-                    generation_state = self.generator.throw(
-                        generation_state.exception)
-                    continue
-
-                self._reset_timestamp()
-                generation_state = self._generate_next(generation_state)
-
-        except StopIteration as sie:
-            orchestration_state = OrchestratorState(
-                is_done=True,
-                output=sie.value,
-                actions=self.durable_context.actions,
-                custom_status=self.durable_context.custom_status)
-        except Exception as e:
-            orchestration_state = OrchestratorState(
-                is_done=False,
-                output=None,  # Should have no output, after generation range
-                actions=self.durable_context.actions,
-                error=str(e),
-                custom_status=self.durable_context.custom_status)
+
+        else:
+            self.generator = fn_output
+            try:
+                generation_state = self._generate_next(None)
+
+                while not suspended:
+                    self._add_to_actions(generation_state)
+
+                    if should_suspend(generation_state):
+
+                        # The `is_done` field should be False here unless
+                        # `continue_as_new` was called. Therefore,
+                        # `will_continue_as_new` essentially "tracks"
+                        # whether or not the orchestration is done.
+                        orchestration_state = OrchestratorState(
+                            is_done=self.durable_context.will_continue_as_new,
+                            output=None,
+                            actions=self.durable_context.actions,
+                            custom_status=self.durable_context.custom_status)
+                        suspended = True
+                        continue
+
+                    if (isinstance(generation_state, Task)
+                        or isinstance(generation_state, TaskSet)) and (
+                            generation_state.is_faulted):
+                        generation_state = self.generator.throw(
+                            generation_state.exception)
+                        continue
+
+                    self._reset_timestamp()
+                    generation_state = self._generate_next(generation_state)
+
+            except StopIteration as sie:
+                orchestration_state = OrchestratorState(
+                    is_done=True,
+                    output=sie.value,
+                    actions=self.durable_context.actions,
+                    custom_status=self.durable_context.custom_status)
+            except Exception as e:
+                orchestration_state = OrchestratorState(
+                    is_done=False,
+                    output=None,  # Should have no output, after generation range
+                    actions=self.durable_context.actions,
+                    error=str(e),
+                    custom_status=self.durable_context.custom_status)
+
+        # No output if continue_as_new was called
+        if self.durable_context.will_continue_as_new:
+            orchestration_state._output = None
 
         return orchestration_state.to_json_string()
 
@@ -108,9 +117,13 @@ def _generate_next(self, partial_result):
             gen_result = self.generator.send(partial_result.result)
         else:
             gen_result = self.generator.send(None)
+
         return gen_result
 
     def _add_to_actions(self, generation_state):
+        # Do not add new tasks to action if continue_as_new was called
+        if self.durable_context.will_continue_as_new:
+            return
         if (isinstance(generation_state, Task)
                 and hasattr(generation_state, "action")):
             self.durable_context.actions.append([generation_state.action])
diff --git a/azure/durable_functions/tasks/continue_as_new.py b/azure/durable_functions/tasks/continue_as_new.py
index 552a6c67..dd07765f 100644
--- a/azure/durable_functions/tasks/continue_as_new.py
+++ b/azure/durable_functions/tasks/continue_as_new.py
@@ -1,24 +1,19 @@
 from typing import Any
 
-from ..models.Task import (
-    Task)
 from ..models.actions.ContinueAsNewAction import ContinueAsNewAction
 
 
 def continue_as_new(
-        input_: Any = None) -> Task:
+        context,
+        input_: Any = None):
     """Create a new continue as new action.
 
     Parameters
     ----------
     input_: Any
         The JSON-serializable input to pass to the activity function.
-
-    Returns
-    -------
-    Task
-        A Durable Task that causes the orchestrator reset and start as a new orchestration.
     """
     new_action = ContinueAsNewAction(input_)
 
-    return Task(is_completed=False, is_faulted=False, action=new_action)
+    context.actions.append([new_action])
+    context._continue_as_new_flag = True
diff --git a/tests/orchestrator/test_continue_as_new.py b/tests/orchestrator/test_continue_as_new.py
index 8c8f1595..ec7956d9 100644
--- a/tests/orchestrator/test_continue_as_new.py
+++ b/tests/orchestrator/test_continue_as_new.py
@@ -10,7 +10,7 @@
 
 def generator_function(context):
     yield context.call_activity("Hello", "Tokyo")
-    yield context.continue_as_new("Cause I can")
+    context.continue_as_new("Cause I can")
 
 
 def base_expected_state(output=None) -> OrchestratorState:
@@ -25,6 +25,7 @@ def add_hello_action(state: OrchestratorState, input_: str):
 def add_continue_as_new_action(state: OrchestratorState, input_: str):
     action = ContinueAsNewAction(input_=input_)
     state.actions.append([action])
+    state._is_done = True
 
 
 def add_hello_completed_events(

From 1ed44961f4270a9b662308d6468b581db9f5c05d Mon Sep 17 00:00:00 2001
From: David Justo <david.justo.1996@gmail.com>
Date: Wed, 5 Aug 2020 10:20:42 -0700
Subject: [PATCH 13/13] linting fix

---
 azure/durable_functions/models/DurableOrchestrationBindings.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/azure/durable_functions/models/DurableOrchestrationBindings.py b/azure/durable_functions/models/DurableOrchestrationBindings.py
index 98a40f96..8c8d8576 100644
--- a/azure/durable_functions/models/DurableOrchestrationBindings.py
+++ b/azure/durable_functions/models/DurableOrchestrationBindings.py
@@ -17,7 +17,8 @@ def __init__(self, taskHubName: str, creationUrls: Dict[str, str],
         self._task_hub_name: str = taskHubName
         self._creation_urls: Dict[str, str] = creationUrls
         self._management_urls: Dict[str, str] = managementUrls
-        # TODO: we can remove the Optional once we drop support for 1.x, this is always provided in 2.x
+        # TODO: we can remove the Optional once we drop support for 1.x,
+        # this is always provided in 2.x
         self._rpc_base_url: Optional[str] = rpcBaseUrl
         self._client_data = FunctionContext(**kwargs)