Python Django模板过滤器上的装饰器？

我有一个模板过滤器，它执行一个非常简单的任务，并且工作得很好，但是我想在它上面使用一个装饰器。不幸的是，装饰程序导致了一个令人讨厌的django错误，没有任何意义

有效的代码：

@register.filter(name="has_network")
def has_network(profile, network):
    hasnetworkfunc = getattr(profile, "has_%s" % network)
    return hasnetworkfunc()

与Decorator（不起作用）：

以下是错误：

模板语法错误位于/

呈现时捕获到异常： 从空列表中弹出

我已经尝试在装饰器内设置断点，我有理由相信它甚至没有被称为

但以防万一，这里是装饰师（我知道有人会要它）

我（暂时）用一个不做任何事情的模拟装饰器替换了装饰器，但是我仍然得到相同的错误

def cache_function(cache_timeout):
    def wrapper(fn):
        def decorator(*args, **kwargs):
            return fn(*args, **kwargs)
        return decorator
    return wrapper

编辑确认：这是因为装饰程序使用了

*args

和

**kwargs

？我假设调用了

pop（）

，以确保所有筛选器都至少包含一个arg

将装饰器更改为此可修复此问题：

def cache_function(cache_timeout):
    def wrapper(fn):
        def decorator(arg1, arg2):
            return fn(arg1, arg2)
        return decorator
    return wrapper

---

不幸的是，这破坏了装饰器的一般性质：/现在该怎么办？

最终答案：向装饰器添加一个额外的参数，指示装饰的内容

也许有更优雅的东西，但这是可行的

from django.core.cache import cache
from django.db.models.query import QuerySet
try:
    from cPickle import dumps
except:
    from pickle import dumps
from hashlib import sha1

cache_miss = object()

class CantPickleAQuerySet(Exception): pass

def cache_function(cache_timeout, func_type='generic'):
    def wrapper(fn):
        def decorator(*args, **kwargs):
            try:
                cache_indentifiers = "%s%s%s%s" % (
                                         fn.__module__,
                                         fn.__name__,
                                         dumps(args),
                                         dumps(kwargs)
                                         )
            except Exception, e:
                print "Error: %s\nFailed to generate cache key: %s%s" % (e, fn.__module__, fn.__name__)
                return fn(*args, **kwargs)

            cache_key = sha1(cache_indentifiers).hexdigest()

            value = cache.get(cache_key, cache_miss)

            if value is cache_miss:
                value = fn(*args, **kwargs)

                if isinstance(value, QuerySet):
                    raise CantPickleAQuerySet("You can't cache a queryset. But you CAN cache a list! just convert your Queryset (the value you were returning) to a list like so `return list(queryset)`")

                try:
                    cache.set(cache_key, value, cache_timeout)
                except Exception, e:
                    print "Error: %s\nFailed to cache: %s\nvalue: %s" % (e, cache_indentifiers, value)

            return value

        no_arg2 = object()
        def filter_decorator(arg1, arg2=no_arg2):
            if arg2 is no_arg2:
                return decorator(arg1)
            else:
                return decorator(arg1, arg2)

        if func_type == 'generic':
            return decorator

        elif func_type == 'filter':
            return filter_decorator

    return wrapper

from django.core.cache import cache
from django.db.models.query import QuerySet
try:
    from cPickle import dumps
except:
    from pickle import dumps
from hashlib import sha1

cache_miss = object()

class CantPickleAQuerySet(Exception): pass

def cache_function(cache_timeout, func_type='generic'):
    def wrapper(fn):
        def decorator(*args, **kwargs):
            try:
                cache_indentifiers = "%s%s%s%s" % (
                                         fn.__module__,
                                         fn.__name__,
                                         dumps(args),
                                         dumps(kwargs)
                                         )
            except Exception, e:
                print "Error: %s\nFailed to generate cache key: %s%s" % (e, fn.__module__, fn.__name__)
                return fn(*args, **kwargs)

            cache_key = sha1(cache_indentifiers).hexdigest()

            value = cache.get(cache_key, cache_miss)

            if value is cache_miss:
                value = fn(*args, **kwargs)

                if isinstance(value, QuerySet):
                    raise CantPickleAQuerySet("You can't cache a queryset. But you CAN cache a list! just convert your Queryset (the value you were returning) to a list like so `return list(queryset)`")

                try:
                    cache.set(cache_key, value, cache_timeout)
                except Exception, e:
                    print "Error: %s\nFailed to cache: %s\nvalue: %s" % (e, cache_indentifiers, value)

            return value

        no_arg2 = object()
        def filter_decorator(arg1, arg2=no_arg2):
            if arg2 is no_arg2:
                return decorator(arg1)
            else:
                return decorator(arg1, arg2)

        if func_type == 'generic':
            return decorator

        elif func_type == 'filter':
            return filter_decorator

    return wrapper