A simple python decorator that prevents calling functions if other class attributes are not set. Beware this breaks the "Errors should never pass silently" rule!

conditional_on.py

from functools import wraps


def has_all_attr(self, *attribute_names):
    '''
    An aid function to determine the condition of "not calling", this could be a parameter of conditional on potentially
    '''
    return all((hasattr(self, attr) and getattr(self, attr) is not None) for attr in attribute_names)


def conditional_on(*parameters):
    def decorator(func):

        @wraps(func)
        def wrapper(self, *args, **kwargs):
            if has_all_attr(self, *parameters):
                func(self, *args, **kwargs)

        return wrapper

    return decorator

if __name__ == '__main__':
    # It works as follows
    class Foo:
        def __init__(self, cond = None):
            self.cond = cond

        @cond('cond')
        def conditionated(self):
            print('Hello world!')
    
       
    non_calling_foo = Foo()
    # The following function will not be called
    non_calling_foo.condtionated()
    
    calling_foo = Foo(3)
    # The following function will print "Hello world!"
    calling_foo.conditionated()