Empty task.config.variables_to_fetch when using **kwargs

[sergiobuj]

Hello!
I am trying to understand the reason why the task.config.variables_to_fetch attribute is empty when including a **kwargs as a parameter.

Consider the following task definitions:

from pyzeebe import ZeebeWorker, create_insecure_channel

channel = create_insecure_channel(hostname="localhost", port=26500)
worker = ZeebeWorker(channel)

@worker.task(task_type="example")
def example_task_var(input: str) -> dict:
    return {"output": f"Hello world, {input}!"}

@worker.task(task_type="extended_example")
def example_task_var_and_kwargs(input: str, **kwargs) -> dict:
    return {"output": f"Hello world, {input}!"}

From these, I would expect the following:

# This is fine and expected
assert task1.config.variables_to_fetch == ["input"], task1.config.variables_to_fetch

# Here, while we can't specify all the possible variables. We do know about 'input'.
assert task2.config.variables_to_fetch == ["input"], task2.config.variables_to_fetch

However, it returns empty:

assert task2.config.variables_to_fetch == ["input"], task2.config.variables_to_fetch
       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
AssertionError: []

Any ideas on what might be reasoning behind this choice?

Here's the source code:

pyzeebe/pyzeebe/function_tools/parameter_tools.py

Line 10 in 9aa314d

def get_parameters_from_function(task_function: Function[..., Any]) -> Optional[List[str]]:

Thanks!

[dimastbk]

Hi. It's empty because of pyzeebe retrieve all variables when kwargs is present (and variables_to_fetch is passed to ActivateJobsRequest, because of empty fetchVariable retrieves all variables). See https://github.com/camunda-community-hub/pyzeebe/blob/master/pyzeebe/function_tools/parameter_tools.py#L10