Example of a Python decorator which accepts parameters.

decorator_example.py

import functools
import inspect

# my_meta = {
#     "a": "ay",
#     "b": "bee",
# }
#
#
# def metadecorator(name, meta=None):
#     def decorator_name(func):
#         @functools.wraps(func)
#         def wrapper(*args, **kwargs):
#             if meta is not None and name in meta:
#                 return meta[name]
#             else:
#                 return func(*args, **kwargs)
#
#         return wrapper
#
#     return decorator_name
#
#
# @metadecorator(meta=my_meta, name="foobz")
# def my_foo():
#     return "fooby"
#
#
# def my_bar(a, b):
#     return (a, b)
#
#
# print("my_foo", my_foo())
#
#
# print("my_bar", my_bar("a", "b"))
#
# meta_my_bar = metadecorator(name="b", meta=my_meta)(my_bar)
#
# print("meta_my_bar", meta_my_bar("a", "b"))
#
# print(metadecorator(name="b", meta=my_meta)(my_bar)("aa", "bb"))

def generic_respect_required_args(required_kwargs):
    def outer_wrapper(function):
        @functools.wraps(function)
        def wrapper(*args, **kwargs):

            parameters = inspect.signature(function).parameters
            all_args = dict(zip(parameters, args), **kwargs)

            for required_kwarg in required_kwargs:

                if all_args.get(required_kwarg) is None:

                    return None

            return function(*args, **kwargs)
        return wrapper
    return outer_wrapper


import logging
log = logging.getLogger("loggy")
logging.basicConfig(level=logging.DEBUG)


@generic_respect_required_args(required_kwargs=['a','b'])
def my_fun(a, b=None, c=7):
    return (a, b, c)

log.info(my_fun(1, 2, 3))
log.info(my_fun(a=1, b=2, c=3))
log.info(my_fun(a=1, b=2, c=None))
log.info(my_fun(None, b=1, c=1)) #
log.info(my_fun(1, None, c=1)) #
log.info(my_fun(1, 2, None))
log.info(my_fun(1, 2, c=None))