src/pydolphinscheduler/tasks/func_wrap.py

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"""Task function wrapper allows using decorator to create a task."""

import functools
import inspect
import itertools
import types

from pydolphinscheduler.exceptions import PyDSParamException
from pydolphinscheduler.tasks.python import Python


def _get_func_str(func: types.FunctionType) -> str:
    """Get Python function string without indent from decorator.

    :param func: The function which wraps by decorator ``@task``.
    """
    lines = inspect.getsourcelines(func)[0]

    src_strip = ""
    lead_space_num = None
    for line in lines:
        if lead_space_num is None:
            lead_space_num = sum(1 for _ in itertools.takewhile(str.isspace, line))
        if line.strip() == "@task":
            continue
        elif line.strip().startswith("@"):
            raise PyDSParamException(
                "Do no support other decorators for function ``task`` decorator."
            )
        src_strip += line[lead_space_num:]
    return src_strip


def task(func: types.FunctionType):
    """Decorate which covert Python function into pydolphinscheduler task."""

    @functools.wraps(func)
    def wrapper(*args, **kwargs):
        func_str = _get_func_str(func)
        return Python(
            name=kwargs.get("name", func.__name__), definition=func_str, *args, **kwargs
        )

    return wrapper