[Core feature] Flytekit create automatic bindings for Task default values

[kumare3]

Motivation: Why do you think this is important?

Currently this will not work, as rotation is not provided

@task(cache=True, cache_version="1")
def rotate_image(img: FlyteFile, rotation: int = 180) -> FlyteFile:
    img.download()
    with Image.open(img.path) as im:
        rotated = im.rotate(rotation)
        rotated.save("/tmp/rotated.jpeg")
    return FlyteFile("/tmp/rotated.jpeg")


@workflow
def wf(img: FlyteFile = "testdir/maradona.jpeg") -> FlyteFile:
    return rotate_image(img=img)

Goal: What should the final outcome look like, ideally?

Ideally we should automatically create a node binding in the workflow where the default value in the task inputs should be added to the node in the workflow

Describe alternatives you've considered

NA

Propose: Link/Inline OR Additional context

No response

Are you sure this issue hasn't been raised already?

• [X] Yes

Have you read the Code of Conduct?

• [X] Yes

### Tasks

[Future-Outlier]

Will start it after 5/12, thank you

[runllm[bot]]

The issue you're describing relates to the current limitation in Flyte where default values for task inputs are not automatically recognized and used in workflows. This is a known limitation, as discussed in GitHub issue #2426, where the Flyte type system does not automatically bind default values or None for optional variables unless explicitly provided. This behavior is intentional to ensure explicitness in workflow definitions.

Your proposed feature to automatically create node bindings for default task input values in workflows would require changes to the FlyteIDL and the core handling of task and workflow interfaces. This feature could simplify workflow definitions by reducing the need for explicit default value bindings at the workflow level, aligning task behavior more closely with standard Python function behavior.

Would you like more detail on how this could be implemented or the current discussions around this feature?

Sources:

• Support for Optional value types in Tasks
• And launchplans seem the only way to specify default values
• Me again I have a question about default parameters

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[MortalHappiness]

#take