如何将自己传递给装饰者?

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如何将self.key传递给装饰器?

    class CacheMix(object):

        def __init__(self,*args,**kwargs):
            super(CacheMix,self).__init__(*args,**kwargs)

        key_func = Constructor(
            memoize_for_request=True,params={'updated_at': self.key}
        )

        @cache_response(key_func=key_func)
        def list(self,**kwargs):
            pass

    class ListView(CacheMix,generics.ListCreateAPIView):
        key = 'test_key'

我收到错误

'self' is not defined
最佳答案
这是一个用类装饰器做的例子,我试着在评论中向你描述.我在你的问题中填写了一些未定义的引用,并使用了cache_response函数装饰器的超简化版本,但希望这将足够具体地传达这个想法,使你能够适应你的真实代码.

import inspect
import types

class Constructor(object):
    def __init__(self,memoize_for_request=True,params=None):
        self.memoize_for_request = memoize_for_request
        self.params = params
    def __call__(self):
        def key_func():
            print('key_func called with params:')
            for k,v in self.params.items():
                print('  {}: {!r}'.format(k,v))
        key_func()

def cache_response(key_func):
    def decorator(fn):
        def decorated(*args,**kwargs):
            key_func()
            fn(*args,**kwargs)
        return decorated
    return decorator

def example_class_decorator(cls):
    key_func = Constructor(  # define key_func here using cls.key
        memoize_for_request=True,params={'updated_at': cls.key} # use decorated class's attribute
    )
    # create and apply cache_response decorator to marked methods
    # (in Python 3 use types.FunctionType instead of types.UnboundMethodType)
    decorator = cache_response(key_func)
    for name,fn in inspect.getmembers(cls):
        if isinstance(fn,types.UnboundMethodType) and hasattr(fn,'marked'):
            setattr(cls,name,decorator(fn))
    return cls

def decorate_me(fn):
    setattr(fn,'marked',1)
    return fn

class CacheMix(object):
    def __init__(self,**kwargs):
        super(CacheMix,**kwargs)

    @decorate_me
    def list(self,**kwargs):
        classname = self.__class__.__name__
        print('list() method of {} object called'.format(classname))

@example_class_decorator
class ListView(CacheMix):
    key = 'test_key'

listview = ListView()
listview.list()

输出

key_func called with params:
  updated_at: 'test_key'
list() method of ListView object called
原文链接:https://www.f2er.com/python/438440.html

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