[sdk] Component parameters with 'Bool' type cannot be used in conditions ("invalid truth value")

[senarvi]

Environment

• KFP SDK version: kfp 1.6.3 kfp-pipeline-spec 0.1.8 kfp-server-api 1.6.0

Steps to reproduce

Using a boolean parameter in an "if" condition in container arguments used to work in kfp==1.4.0, but kfp==1.6.x gives the following "invalid truth value" error (apparently trying to pass the parameter placeholder to strtobool() even if the value is available):

Traceback (most recent call last):
  File "test_case.py", line 25, in <module>
    compiler.Compiler().compile(pipeline, 'pipeline.yaml')
  File ".../lib/python3.9/site-packages/kfp/compiler/compiler.py", line 1053, in compile
    self._create_and_write_workflow(
  File ".../lib/python3.9/site-packages/kfp/compiler/compiler.py", line 1106, in _create_and_write_workflow
    workflow = self._create_workflow(
  File ".../lib/python3.9/site-packages/kfp/compiler/compiler.py", line 896, in _create_workflow
    pipeline_func(*args_list, **kwargs_dict)
  File "test_case.py", line 22, in pipeline
    op()
  File ".../lib/python3.9/site-packages/kfp/components/_dynamic.py", line 34, in Component
    return dict_func(locals())  # noqa: F821 TODO
  File ".../lib/python3.9/site-packages/kfp/components/_components.py", line 343, in create_task_object_from_component_and_pythonic_arguments
    return _create_task_object_from_component_and_arguments(
  File ".../lib/python3.9/site-packages/kfp/components/_components.py", line 290, in _create_task_object_from_component_and_arguments
    task = _container_task_constructor(
  File ".../lib/python3.9/site-packages/kfp/dsl/_component_bridge.py", line 302, in _create_container_op_from_component_and_arguments
    _attach_v2_specs(task, component_spec, original_arguments)
  File ".../lib/python3.9/site-packages/kfp/dsl/_component_bridge.py", line 596, in _attach_v2_specs
    resolved_cmd = _resolve_commands_and_args_v2(
  File ".../lib/python3.9/site-packages/kfp/dsl/_component_bridge.py", line 442, in _resolve_commands_and_args_v2
    resolved_cmd = _components._resolve_command_line_and_paths(
  File ".../lib/python3.9/site-packages/kfp/components/_components.py", line 511, in _resolve_command_line_and_paths
    expanded_args = expand_argument_list(container_spec.args)
  File ".../lib/python3.9/site-packages/kfp/components/_components.py", line 502, in expand_argument_list
    expanded_part = expand_command_part(part)
  File ".../lib/python3.9/site-packages/kfp/components/_components.py", line 482, in expand_command_part
    condition_result_bool = condition_result and strtobool(condition_result) #Python gotcha: bool('False') == True; Need to use strtobool; Also need to handle None and []
  File ".../lib/python3.9/distutils/util.py", line 320, in strtobool
    raise ValueError("invalid truth value %r" % (val,))
ValueError: invalid truth value "{{$.inputs.parameters['enable']}}"

Code to reproduce the problem:

# test_case.py

@dsl.pipeline(name="Pipeline", description="Pipeline")
def pipeline() -> None:
    op = components.load_component_from_text(
        """
        name: Component
        inputs:
        - {name: enable, type: Bool, default: False}
        implementation:
          container:
            image: some/container
            args:
            - if:
                cond:
                  inputValue: enable
                then:
                  - '--enable'
        """
    )

    op()

if __name__ == '__main__':
    compiler.Compiler().compile(pipeline, 'pipeline.yaml')

Expected result

The pipeline is expected to compile. In the code sample, the component would not have any arguments. Calling op(True) would add the --enable argument to the component. (This is how kfp==1.4.0 works.)

---

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[Bobgy]

/cc @chensun

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[senarvi]

Bump

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[BroderPeters]

Is there any workaround or alternative that can be used?

[senarvi]

Started using Kubeflow after a long while and ran into this problem again with Kubeflow 1.8.22. I think this workaround should work:

• Make the default value of all Bool parameters False.
• Use isPresent instead of the inputValue condition.
• Never set a parameter to False, i.e. either use the default or True.

[senarvi]

The workaround gets tricky if you want to pass a boolean pipeline parameter to the component. I thought it would be possible (although ugly) using two dsl.Conditions in the pipeline: one dsl.Condition is executed when the pipeline parameter is True and passes a True value to the component and the other one is executed when the pipeline parameter is False and doesn't pass the component parameter. However, I couldn't get it to work due to another bug. Maybe it works in KFP 2.0.

[github-actions[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[github-actions[bot]]

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