Accessing client_stream_profile settings in UDP stream app results in exception

[njferrant]

Issue:

When calling session.config.config.traffic_profiles[0].applications[0].stateless_stream.client_stream_profile the following exception occurs:

Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/home/user/cyperf-rest-client/.venv/lib/python3.11/site-packages/cyperf/dynamic_model_meta.py", line 361, in get_by_link
    field = self.link_based_request(link.name, "GET",
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/user/cyperf-rest-client/.venv/lib/python3.11/site-packages/cyperf/dynamic_model_meta.py", line 302, in <lambda>
    c.link_based_request = lambda self, link_name, method, return_type=None, body=None, query=[]: cls.link_based_request(self, link_name, method, return_type, body, query)
                                                                                                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/user/cyperf-rest-client/.venv/lib/python3.11/site-packages/cyperf/dynamic_model_meta.py", line 507, in link_based_request
    response = self.api_client.call_api(
               ^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/user/cyperf-rest-client/.venv/lib/python3.11/site-packages/cyperf/api_client.py", line 385, in call_api
    return self.__retry(lambda: self.__call_api(method, url, header_params,
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/user/cyperf-rest-client/.venv/lib/python3.11/site-packages/cyperf/api_client.py", line 127, in __retry
    result = request_func()
             ^^^^^^^^^^^^^^
  File "/home/user/cyperf-rest-client/.venv/lib/python3.11/site-packages/cyperf/api_client.py", line 385, in <lambda>
    return self.__retry(lambda: self.__call_api(method, url, header_params,
                                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/user/cyperf-rest-client/.venv/lib/python3.11/site-packages/cyperf/api_client.py", line 359, in __call_api
    return DynamicModel.dynamic_wrapper(self.response_deserialize(
                                        ^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/user/cyperf-rest-client/.venv/lib/python3.11/site-packages/cyperf/api_client.py", line 425, in response_deserialize
    return_data = self.deserialize(response_text, response_type, content_type)
                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/user/cyperf-rest-client/.venv/lib/python3.11/site-packages/cyperf/api_client.py", line 527, in deserialize
    return self.__deserialize(data, response_type)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/user/cyperf-rest-client/.venv/lib/python3.11/site-packages/cyperf/api_client.py", line 581, in __deserialize
    return self.__deserialize_model(data, klass)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/user/cyperf-rest-client/.venv/lib/python3.11/site-packages/cyperf/api_client.py", line 902, in __deserialize_model
    return klass.from_dict(data)
           ^^^^^^^^^^^^^^^^^^^^^
  File "/home/user/cyperf-rest-client/.venv/lib/python3.11/site-packages/cyperf/models/stream_profile.py", line 92, in from_dict
    _obj = cls.model_validate({
           ^^^^^^^^^^^^^^^^^^^^
  File "/home/user/cyperf-rest-client/.venv/lib/python3.11/site-packages/pydantic/main.py", line 705, in model_validate
    return cls.__pydantic_validator__.validate_python(
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
pydantic_core._pydantic_core.ValidationError: 1 validation error for StreamProfile
payloadType
  Input should be 'RANDOM', 'PSEUDORANDOM' or '<nil>' [type=enum, input_value='null', input_type=str]
    For further information visit https://errors.pydantic.dev/2.11/v/enum

It looks like the API is returning null for the StreamPayloadType (in client StreamProfile), which is being converted to the string 'null'. StreamPayloadType is expecting '<nil>', thus the exception.

Versions:

CyPerf Controller: 7.0 (build 14934)
cyperf-api-wrapper: commit c8e07832bf2befa4f3c1b179a422c0bfb3f2d69c
python: 3.11

Workaround:

I'm doing the following (shown as a diff patch):

--- stream_payload_type.py.orig 2025-09-08 13:22:09
+++ stream_payload_type.py      2025-09-08 13:22:23
@@ -29,7 +29,7 @@
     """
     RANDOM = 'RANDOM'
     PSEUDORANDOM = 'PSEUDORANDOM'
-    LESS_THAN_NIL_GREATER_THAN = '<nil>'
+    LESS_THAN_NIL_GREATER_THAN = 'null'
 
     @classmethod
     def from_json(cls, json_str: str) -> Self:

[tsimionescu]

Thank you for reporting this! It should be fixed in the latest build available in PyPI, and in the latest code here. We actually renamed the constant as well, so you will find at as NULL instead of LESS_THAN_NIL_GREATER_THAN.