[Core Feature] flytekit - support positional args when calling tasks

[tekumara]

Flytekit doesn't support positional args for calling tasks in a workflow, eg:

from dataclasses import dataclass
from dataclasses_json import dataclass_json
from flytekit import task, workflow

@dataclass_json
@dataclass
class dc:
    its_a_kind_of:str

@task
def generate_reference_data() -> dc:
    return dc(its_a_kind_of="MAGIC")

@task
def process_reference_data(data: dc) -> str:
    return data.its_a_kind_of

@workflow
def main() -> str:
    reference_data = generate_reference_data()
    # Flyte takes keyword args here only
    return process_reference_data(reference_data)

if __name__ == "__main__":
    print(main())

Will error with

flytekit.common.exceptions.user.FlyteAssertion: When calling tasks, only keyword args are supported. Aborting execution as detected 1 positional args (Promise(node:n0.o0),)

Motivation: Why do you think this is important?

Supporting positional args would reduce friction when converting existing Python scripts to Flyte workflows.

[hebiao064]

It should be supported now, maybe this issue could be closed.

from dataclasses import dataclass
from dataclasses_json import dataclass_json
from flytekit import task, workflow


@dataclass_json
@dataclass
class dc:
    its_a_kind_of: str


@task
def generate_reference_data() -> dc:
    return dc(its_a_kind_of="MAGIC")


@task
def process_reference_data(data: dc) -> str:
    print("start executing process_reference_data task")
    return data.its_a_kind_of


@workflow
def main() -> str:
    reference_data = generate_reference_data()
    # Flyte takes keyword args here only
    return process_reference_data(data=reference_data)


if __name__ == "__main__":
    print(main())

[eapolinario]

We don't have plans to support this feature at this time.