[PYTHON/COMMON] 메타 클래스 : 자식 클래스 직렬화/역직렬화 기능 추가하기

■ 메타 클래스를 사용해 자식 클래스에 직렬화/역직렬화 기능을 추가하는 방법을 보여준다.

▶ 예제 코드 (PY)


import json

serializableClassDictionary = {}

def registerClass(sourceClass):
    serializableClassDictionary[sourceClass.__name__] = sourceClass

class RegisteredSerializableMeta(type):
    def __new__(metaClass, className, baseClassTuple, classMemberDictionary):
        classInstance = type.__new__(metaClass, className, baseClassTuple, classMemberDictionary)
        registerClass(classInstance)
        return classInstance

class Serializable:
    def __init__(self, *argumentTuple):
        self.argumentTuple = argumentTuple

    def serialize(self):
        return json.dumps(
            {
                "className"     : self.__class__.__name__,
                "argumentTuple" : self.argumentTuple,
            }
        )

class RegisteredSerializable(Serializable, metaclass = RegisteredSerializableMeta):
    pass

def deserialize(jsonString):
    jsonDictionary = json.loads(jsonString)
    className = jsonDictionary["className"]
    targetClassName = serializableClassDictionary[className]
    return targetClassName(*jsonDictionary["argumentTuple"])

class Vector3D(RegisteredSerializable):
    def __init__(self, x, y, z):
        super().__init__(x, y, z)
        self.x, self.y, self.z = x, y, z

vector = Vector3D(10, -7, 3)

jsonString = vector.serialize()

print("기존     : ", vector                 )
print("직렬화   : ", jsonString             )
print("역직렬화 : ", deserialize(jsonString))

"""
기존     :  <__main__.Vector3D object at 0x7fab3278fb80>
직렬화   :  {"className": "Vector3D", "argumentTuple": [10, -7, 3]}
역직렬화 :  <__main__.Vector3D object at 0x7fab325d9930>
"""

import json

serializableClassDictionary = {}

def registerClass(sourceClass):

serializableClassDictionary[sourceClass.__name__] = sourceClass

class RegisteredSerializableMeta(type):

def __new__(metaClass, className, baseClassTuple, classMemberDictionary):

classInstance = type.__new__(metaClass, className, baseClassTuple, classMemberDictionary)

registerClass(classInstance)

return classInstance

class Serializable:

def __init__(self, *argumentTuple):

self.argumentTuple = argumentTuple

def serialize(self):

return json.dumps(

{

"className" : self.__class__.__name__,

"argumentTuple" : self.argumentTuple,

}

)

class RegisteredSerializable(Serializable, metaclass = RegisteredSerializableMeta):

pass

def deserialize(jsonString):

jsonDictionary = json.loads(jsonString)

className = jsonDictionary["className"]

targetClassName = serializableClassDictionary[className]

return targetClassName(*jsonDictionary["argumentTuple"])

class Vector3D(RegisteredSerializable):

def __init__(self, x, y, z):

super().__init__(x, y, z)

self.x, self.y, self.z = x, y, z

vector = Vector3D(10, -7, 3)

jsonString = vector.serialize()

print("기존 : ", vector )

print("직렬화 : ", jsonString )

print("역직렬화 : ", deserialize(jsonString))

"""

기존 : <__main__.Vector3D object at 0x7fab3278fb80>

직렬화 : {"className": "Vector3D", "argumentTuple": [10, -7, 3]}

역직렬화 : <__main__.Vector3D object at 0x7fab325d9930>

"""