Files
PyPattyrn/pypat/creational/factory.py
2016-09-10 17:11:45 -04:00

61 lines
2.0 KiB
Python

from abc import abstractmethod, ABCMeta
class Factory(object, metaclass=ABCMeta):
"""
Factory Interface.
All Factories should inherit this class and overwrite the create method.
- External Usage documentation: U{https://github.com/tylerlaberge/PyPatterns/wiki/Creational-Pattern-Usage}
- External Factory Pattern documentation: U{https://en.wikipedia.org/wiki/Factory_method_pattern}
"""
@abstractmethod
def create(self, **kwargs):
"""
Abstract create method.
Concrete implementations should return a new instance of the object the factory class is responsible for.
@param kwargs: Arguments for object creation.
@return: A new instance of the object the factory is responsible for.
"""
pass
class AbstractFactory(Factory, metaclass=ABCMeta):
"""
Abstract Factory Class as part of the AbstractFactory design pattern.
- External Usage documentation: U{https://github.com/tylerlaberge/PyPatterns/wiki/Creational-Pattern-Usage}
- External Abstract Factory Pattern documentation: U{https://en.wikipedia.org/wiki/Abstract_factory_pattern}
"""
def __init__(self):
"""
Initialize the abstract factory.
Concrete implementations should call this from within their own __init__ method
and register all their factories to keys using the register method.
"""
self._factories = dict()
@abstractmethod
def create(self, **kwargs):
"""
Abstract create method.
Concrete implementations should return a new instance of an object by calling the appropriate factory.
@param kwargs: Arguments for object creation.
"""
pass
def _register(self, key, factory):
"""
Register a factory to a key.
@param key: Key for identifying which factory to use.
@type key: str
@param factory: The factory to register to the key.
"""
self._factories[str(key)] = factory