so_magic.data.features.phi.PhiFunctionRegistrator.register()

Complexity

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6

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Total Lines	87
Code Lines	21

Duplication

Lines	0
Ratio	0 %

Importance

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0

"""This module is responsible to provide a formal way of registering phi functions
    @classmethod
    def register(cls, phi_name=''):
        """Add a new phi function to phi function registry and notify listeners/observers.

        Use this decorator around either a callable function (defined with the 'def' python special word) or a class
        with a takes-no-arguments (or all-optional-arguments) constructor and a __call__ magic method.

        All phi functions are expected to be registered with a __name__ and a __doc__ attribute.

        You can select your custom phi_name under which to register the phi function or default to an automatic
        determination of the phi_name to use.

        Automatic determination of phi_name is done by examining either the __name__ attribute of the function or the
        class name of the class.

        Example:

            >>> from so_magic.data.features.phi import PhiFunctionRegistry, PhiFunctionRegistrator

            >>> registered_phis = PhiFunctionRegistry()

            >>> @PhiFunctionRegistrator.register()
            ... def f1(x):
            ...  return x * 2
            Registering input function f1 as phi function, at key f1.

            >>> input_value = 5
            >>> print(f"{input_value} * 2 = {registered_phis.get('f1')(input_value)}")
            5 * 2 = 10

            >>> @PhiFunctionRegistrator.register()
            ... class f2:
            ...  def __call__(self, data, **kwargs):
            ...   return data + 5
            Registering input class f2 instance as phi function, at key f2.

            >>> input_value = 1
            >>> print(f"{input_value} + 5 = {registered_phis.get('f2')(input_value)}")
            1 + 5 = 6

            >>> @PhiFunctionRegistrator.register('f3')
            ... class MyCustomClass:
            ...  def __call__(self, data, **kwargs):
            ...   return data + 1
            Registering input class MyCustomClass instance as phi function, at key f3.

            >>> input_value = 3
            >>> print(f"{input_value} + 1 = {registered_phis.get('f3')(input_value)}")
            3 + 1 = 4

        Args:
            phi_name (str, optional): custom name to register the phi function. Defaults to automatic computation.
        """
        def wrapper(a_callable):
            """Add a callable object to the phi function registry and preserve info for __name__ and __doc__ attributes.

            The callable object should either be function (defined with def) or a class (defined with class). In case of
            a class the class must have a constructor that takes no arguments (or all arguments are optional) and a
            __call__ magic method.

            Registers the callable as a phi function under the given or automatically computed name, makes sure the
            __name__ and __doc__ attributes preserve information and notifies potential listeners/observers.

            Args:
                a_callable (Callable): the object (function or class) to register as phi function
            """
            if hasattr(a_callable, '__code__'):  # it is a function (def func_name ..)
                logging.info("Registering input function %s as phi function.", a_callable.__code__.co_name)
                key = phi_name if phi_name else cls.get_name(a_callable)
                print(f"Registering input function {a_callable.__code__.co_name} as phi function, at key {key}.")
                cls._register(a_callable, key)
            else:
                if not hasattr(a_callable, '__call__'):
                    raise RuntimeError("Expected an class definition with a '__call__' instance method defined 1."
                                       f" Got {type(a_callable)}")
                members = inspect.getmembers(a_callable)
                if ('__call__', a_callable.__call__) not in members:
                    raise RuntimeError("Expected an class definition with a '__call__' instance method defined 2."
                                       f" Got {type(a_callable)}")
                instance = a_callable()
                instance.__name__ = a_callable.__name__
                instance.__doc__ = a_callable.__call__.__doc__
                key = phi_name if phi_name else cls.get_name(instance)
                print(f"Registering input class {a_callable.__name__} instance as phi function, at key {key}.")
                cls._register(instance, key)
            return a_callable
        return wrapper