from flytekit import workflow, task
from flytekit.types.file import FlyteFile


@task
def task_long(f_in: FlyteFile) -> int:
    data = f_in.open("r").read()
    print(data)
    ret = len(data)
    return ret


@workflow
def runme(input_file: FlyteFile) -> int:
    return task_long(input_file)

$ pyflyte run   --remote  tmptest.py runme --input_file ./1ycr.pdb
Failed with Exception Code: USER:AssertionError
Underlying Exception: When calling tasks, only keyword args are supported. Aborting execution as detected 1 positional args (Promise(node:.input_file),)
Error encountered while executing 'runme':
  When calling tasks, only keyword args are supported. Aborting execution as detected 1 positional args (Promise(node:.input_file),)

from flytekit import workflow, task, dynamic
from flytekit.types.file import FlyteFile


@task
def task_long(f_in: FlyteFile) -> int:
    with f_in.open("r") as fh:
        data = fh.read()
    print(data)
    ret = len(data)
    return ret


@workflow
def runme(input_file: FlyteFile) -> int:
    return task_long(f_in=input_file)