Allow overriding orchestration version when starting orchestrations via APIs

azure/durable_functions/models/DurableOrchestrationClient.py

@@ -48,7 +48,8 @@ def __init__(self, context: str):
     async def start_new(self,
                         orchestration_function_name: str,
                         instance_id: Optional[str] = None,
-                        client_input: Optional[Any] = None) -> str:
+                        client_input: Optional[Any] = None,
+                        version: Optional[str] = None) -> str:
         """Start a new instance of the specified orchestrator function.
 
         If an orchestration instance with the specified ID already exists, the
@@ -63,14 +64,19 @@ async def start_new(self,
             the Durable Functions extension will generate a random GUID (recommended).
         client_input : Optional[Any]
             JSON-serializable input value for the orchestrator function.
+        version : Optional[str]
+            The version to assign to the orchestration instance. If not specified,
+            the defaultVersion from host.json will be used.
 
         Returns
         -------
         str
             The ID of the new orchestration instance if successful, None if not.
         """
         request_url = self._get_start_new_url(
-            instance_id=instance_id, orchestration_function_name=orchestration_function_name)
+            instance_id=instance_id,
+            orchestration_function_name=orchestration_function_name,
+            version=version)
 
         trace_parent, trace_state = DurableOrchestrationClient._get_current_activity_context()
 
@@ -639,10 +645,15 @@ def _parse_purge_instance_history_response(
             raise Exception(result)
 
     def _get_start_new_url(
-            self, instance_id: Optional[str], orchestration_function_name: str) -> str:
+            self, instance_id: Optional[str], orchestration_function_name: str,
+            version: Optional[str] = None) -> 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}'
+
+        if version is not None:
+            request_url += f'?version={quote(version)}'
+
         return request_url
 
     def _get_raise_event_url(

azure/durable_functions/models/DurableOrchestrationContext.py

@@ -285,7 +285,8 @@ def call_http(self, method: str, uri: str, content: Optional[str] = None,
 
     def call_sub_orchestrator(self,
                               name: Union[str, Callable], input_: Optional[Any] = None,
-                              instance_id: Optional[str] = None) -> TaskBase:
+                              instance_id: Optional[str] = None,
+                              version: Optional[str] = None) -> TaskBase:
         """Schedule sub-orchestration function named `name` for execution.
 
         Parameters
@@ -296,6 +297,9 @@ def call_sub_orchestrator(self,
             The JSON-serializable input to pass to the orchestrator function.
         instance_id: Optional[str]
             A unique ID to use for the sub-orchestration instance.
+        version: Optional[str]
+            The version to assign to the sub-orchestration instance. If not specified,
+            the defaultVersion from host.json will be used.
 
         Returns
         -------
@@ -313,14 +317,15 @@ def call_sub_orchestrator(self,
         if isinstance(name, FunctionBuilder):
             name = self._get_function_name(name, OrchestrationTrigger)
 
-        action = CallSubOrchestratorAction(name, input_, instance_id)
+        action = CallSubOrchestratorAction(name, input_, instance_id, version)
         task = self._generate_task(action)
         return task
 
     def call_sub_orchestrator_with_retry(self,
                                          name: Union[str, Callable], retry_options: RetryOptions,
                                          input_: Optional[Any] = None,
-                                         instance_id: Optional[str] = None) -> TaskBase:
+                                         instance_id: Optional[str] = None,
+                                         version: Optional[str] = None) -> TaskBase:
         """Schedule sub-orchestration function named `name` for execution, with retry-options.
 
         Parameters
@@ -333,6 +338,9 @@ def call_sub_orchestrator_with_retry(self,
             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.
+        version: Optional[str]
+            The version to assign to the sub-orchestration instance. If not specified,
+            the defaultVersion from host.json will be used.
 
         Returns
         -------
@@ -350,7 +358,8 @@ def call_sub_orchestrator_with_retry(self,
         if isinstance(name, FunctionBuilder):
             name = self._get_function_name(name, OrchestrationTrigger)
 
-        action = CallSubOrchestratorWithRetryAction(name, retry_options, input_, instance_id)
+        action = CallSubOrchestratorWithRetryAction(
+            name, retry_options, input_, instance_id, version)
         task = self._generate_task(action, retry_options)
         return task
 

azure/durable_functions/models/actions/CallSubOrchestratorAction.py

@@ -11,10 +11,11 @@ class CallSubOrchestratorAction(Action):
     """Defines the structure of the Call SubOrchestrator object."""
 
     def __init__(self, function_name: str, _input: Optional[Any] = None,
-                 instance_id: Optional[str] = None):
+                 instance_id: Optional[str] = None, version: Optional[str] = None):
         self.function_name: str = function_name
         self._input: str = dumps(_input, default=_serialize_custom_object)
         self.instance_id: Optional[str] = instance_id
+        self.version: Optional[str] = version
 
         if not self.function_name:
             raise ValueError("function_name cannot be empty")
@@ -37,4 +38,5 @@ def to_json(self) -> Dict[str, Union[str, int]]:
         add_attrib(json_dict, self, 'function_name', 'functionName')
         add_attrib(json_dict, self, '_input', 'input')
         add_attrib(json_dict, self, 'instance_id', 'instanceId')
+        add_attrib(json_dict, self, 'version', 'version')
         return json_dict

azure/durable_functions/models/actions/CallSubOrchestratorWithRetryAction.py

@@ -13,11 +13,12 @@ class CallSubOrchestratorWithRetryAction(Action):
 
     def __init__(self, function_name: str, retry_options: RetryOptions,
                  _input: Optional[Any] = None,
-                 instance_id: Optional[str] = None):
+                 instance_id: Optional[str] = None, version: 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: Optional[str] = instance_id
+        self.version: Optional[str] = version
 
         if not self.function_name:
             raise ValueError("function_name cannot be empty")
@@ -41,4 +42,5 @@ def to_json(self) -> Dict[str, Union[str, int]]:
         add_attrib(json_dict, self, '_input', 'input')
         add_json_attrib(json_dict, self, 'retry_options', 'retryOptions')
         add_attrib(json_dict, self, 'instance_id', 'instanceId')
+        add_attrib(json_dict, self, 'version', 'version')
         return json_dict

samples-v2/orchestration_versioning/README.md

@@ -33,7 +33,7 @@ What happens to *existing orchestration instances* that were started *before* th
 6. Trigger the external event.
 7. Observe that the orchestration output.
 
-```
+```text
 Orchestration version: 1.0
 Suborchestration version: 2.0
 Hello from A!
@@ -42,3 +42,33 @@ Hello from A!
 Note that the value returned by `context.version` is permanently associated with the orchestrator instance and is not impacted by the `defaultVersion` change. As a result, the orchestrator follows the old execution path to guarantee deterministic replay behavior.
 
 However, the suborchestration version is `2.0` because this suborchestration was created *after* the `defaultVersion` change.
+
+## Overriding Version Programmatically
+
+In addition to using `defaultVersion` in `host.json`, you can also specify a version explicitly when starting an orchestration using the `version` parameter of `client.start_new()`:
+
+```python
+# Start with a specific version
+instance_id = await client.start_new("my_orchestrator", version="1.5")
+```
+
+You can also specify a version when calling sub-orchestrators from within an orchestrator function:
+
+```python
+# Call sub-orchestrator with specific version
+sub_result = yield context.call_sub_orchestrator('my_sub_orchestrator', version="1.5")
+
+# Call sub-orchestrator with retry and specific version
+sub_result = yield context.call_sub_orchestrator_with_retry(
+    'my_sub_orchestrator',
+    retry_options=retry_options,
+    version="2.0"
+)
+```
+
+When a version is explicitly provided, it takes precedence over the `defaultVersion` in `host.json`. This allows you to:
+
+- Test new orchestration versions without changing configuration
+- Run multiple versions simultaneously
+- Gradually roll out new versions by controlling which requests use which version
+- Running A/B tests with different sub-orchestrator implementations

samples-v2/orchestration_versioning/function_app.py

@@ -8,9 +8,17 @@
 @myApp.durable_client_input(client_name="client")
 async def http_start(req: func.HttpRequest, client):
     function_name = req.route_params.get('functionName')
-    instance_id = await client.start_new(function_name)
 
-    logging.info(f"Started orchestration with ID = '{instance_id}'.")
+    # Get optional version from query parameter
+    version = req.params.get('version')
+
+    if version:
+        instance_id = await client.start_new(function_name, version=version)
+        logging.info(f"Started orchestration with ID = '{instance_id}' and version = '{version}'.")
+    else:
+        instance_id = await client.start_new(function_name)
+        logging.info(f"Started orchestration with ID = '{instance_id}'.")
+
     return client.create_check_status_response(req, instance_id)
 
 @myApp.orchestration_trigger(context_name="context")
@@ -29,18 +37,27 @@ def my_orchestrator(context: df.DurableOrchestrationContext):
     yield context.wait_for_external_event("Continue")
     context.set_custom_status("Continue event received")
 
-    # New sub-orchestrations will use the current defaultVersion specified in host.json
-    sub_result = yield context.call_sub_orchestrator('my_sub_orchestrator')
-    return [f'Orchestration version: {context.version}', f'Suborchestration version: {sub_result}', activity_result]
+    # You can explicitly pass a version to sub-orchestrators
+    sub_result_with_version = yield context.call_sub_orchestrator('my_sub_orchestrator', version="0.9")
+
+    # Without specifying version, the sub-orchestrator will use the current defaultVersion
+    sub_result_default = yield context.call_sub_orchestrator('my_sub_orchestrator')
+
+    return [
+        f'Orchestration version: {context.version}', 
+        f'Suborchestration version (explicit): {sub_result_with_version}',
+        f'Suborchestration version (default): {sub_result_default}',
+        activity_result
+    ]
 
 @myApp.orchestration_trigger(context_name="context")
 def my_sub_orchestrator(context: df.DurableOrchestrationContext):
     return context.version
 
-@myApp.activity_trigger()
-def activity_a() -> str:
+@myApp.activity_trigger(input_name="input")
+def activity_a(input: str) -> str:
     return f"Hello from A!"
 
-@myApp.activity_trigger()
-def activity_b() -> str:
-    return f"Hello from B!"
+@myApp.activity_trigger(input_name="input")
+def activity_b(input: str) -> str:
+    return f"Hello from B!"

samples-v2/orchestration_versioning/host.json

@@ -12,5 +12,9 @@
     "durableTask": {
       "defaultVersion": "1.0"
     }
+  },
+  "extensionBundle": {
+    "id": "Microsoft.Azure.Functions.ExtensionBundle",
+    "version": "[4.26.0, 5.0.0)"
   }
 }

tests/models/test_DurableOrchestrationClient.py

@@ -82,6 +82,17 @@ def test_get_start_new_url(binding_string):
     assert expected_url == start_new_url
 
 
+def test_get_start_new_url_with_version(binding_string):
+    client = DurableOrchestrationClient(binding_string)
+    instance_id = "2e2568e7-a906-43bd-8364-c81733c5891e"
+    function_name = "my_function"
+    version = "2.0"
+    start_new_url = client._get_start_new_url(instance_id, function_name, version)
+    expected_url = replace_stand_in_bits(
+        f"{RPC_BASE_URL}orchestrators/{function_name}/{instance_id}?version={version}")
+    assert expected_url == start_new_url
+
+
 def test_get_input_returns_none_when_none_supplied():
     result = DurableOrchestrationClient._get_json_input(None)
     assert result is None