class CustomSerializerClassesMixin():
    serializer_class = None
    request_serialiser_classes = {}  # {'action': SerializerClass}
    response_serializer_classes = {}
    def get_serializer_class(self):
        if hasattr(self, 'action') and self.action in self.request_serialiser_classes:
            return self.request_serialiser_classes[self.action]
        return self.serializer_class
    def get_response_serializer_class(self):
        if hasattr(self, 'action') and self.action in self.response_serializer_classes:
            return self.response_serializer_classes[self.action]
        return self.serializer_class

 # -*- coding: utf-8 -*-
"""-------------------------------------------------------------"""
class ABussinesLogic:
  """
    Абстрактный класс, родитель для конкретных фунций бизнес-логики
  """
  def __init__(self, validator, processor, serializator):
    self.validator = validator
    self.processor = processor
    self.serializator = serializator
  def isValid(self, data):
    return self.validator.isValid(data)
  def process(self, data):
    return self.processor.process(data) # Сама логика
  def serialize(self, data):
    return self.serializator.serialize(data)
"""-------------------------------------------------------------"""
class DocCreator(ABussinesLogic):
  """
  Конкретная функция бизнес-логики
  """
  def __init__():
    super(someValidator, someProcessor, someSerializator)
"""-------------------------------------------------------------"""
class Router:
  """
  Обработчи маршрутов и методов
  """
  """
    Конфиг для REST. Вид:
    route: {
      {
        method1: BussinesLogic1(),
        method2: BussinesLogic2()
      }
    }
  """
  config = {
      '/doc/createBy': {
          'POST': DocCreator(),
         },
     '/doc/': {
          'GET': DocPresenter()
      },
   .....
  }
  def applyRoute(route, method, requestData):
    logic = config[route][method]
    if logic.isValid(requestData):
      try:
        data = logic.process(requestData)
        serilizedData = logic.serialize(data)
        return Response(serilizedData)
      except Exception:
        return Response(500)
    else:
      Response('Not valid')

 class SomeSerializer(serializers.ModelSerializer):
    class Meta:
        model = models.SomeModel
        fields = (
            'id',
            'attribute',
            'oneElseAttribute',       
        )
    oneElseAttribute = serializers.CharField(source='one_else_attribute', validators=[val1, val2])
    def validate(self):
        '''
            Object level validation, must raise ValidationError on failure
        '''
        pass