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
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
