Python 获取函数的局部变量

我正试图从装饰器中获取一个局部变量。例如：

def needs_privilege(privilege, project=None):
    """Check whether the logged-in user is authorised based on the
    given privilege

    @type privilege: Privilege object, id, or str
    @param privilege: The requested privilege"""

    def validate(func, self, *args, **kwargs):
        """Validator of needs_privillige"""
        try: check(self.user, privilege, project)
        except AccessDenied:
            return abort(status_code=401)
        else: 
            return func(self, *args, **kwargs)

    return decorator(validate)

class TestClass(object):
    def needs_privilege(privilege, project=None):
        def wrapper(func):
            def validate(self, *args, **kwargs):
                """Validator of needs_privillige"""
                print 'validator check for %s' % privilege
                return func(*args, **kwargs)
            validate.privilege = privilege
            return validate

        return wrapper

    @needs_privilege("foo")
    def bar():
        print "called"

>>> test.TestClass().bar()
validator check for foo
called
>>> test.TestClass.bar.privilege
'foo'
>>> test.TestClass().bar.privilege
'foo'

修饰函数后，如下所示：

 @needs_privilege("some_privilege")
 def some_function():
     pass

def needs_privilege(privilege, project=None):
    def validate(func):
        def _validate(self, *args, **kwargs):
            return func(self, *args, **kwargs)
        _validate.decorator_args=(privilege,project)
        return _validate
    return validate

@needs_privilege("some_privilege")
def some_function(self):
    pass

a = some_function
print(a.decorator_args)
# ('some_privilege', None)

我想从某个函数中检索“privilige”变量（validate（）使用）。搜索了一个多小时后，我觉得很迷茫。这可能吗

编辑： 让我更彻底地描述一下我的问题：我可以在不执行某些函数的情况下获得字符串“some_prvilege”吗？比如：

a = getattr(module, 'somefunction')
print a.decorator_arguments

---

?？谢谢你迄今为止对我的帮助

您可以将其作为参数传递：

def needs_privilege(privilege, project=None):
    """Check whether the logged-in user is authorised based on the
    given privilege

    @type privilege: Privilege object, id, or str
    @param privilege: The requested privilege"""

    def validate(func, self, *args, **kwargs):
        """Validator of needs_privillige"""
        try: check(self.user, privilege, project)
        except AccessDenied:
            return abort(status_code=401)
        else: 
            return func(self, privilege, *args, **kwargs)

    return decorator(validate)

@needs_privilege("some_privilege")
def some_function(privilege):
    pass

---

您的decorator基本上检查用户是否具有执行给定函数的权限，我不理解您为什么要检索（附加）正在包装的函数的权限，但您可以在不向所有函数添加其他参数的情况下执行此操作

def needs_privilege(privilege, project=None):
    """Check whether the logged-in user is authorised based on the
    given privilege

    @type privilege: Privilege object, id, or str
    @param privilege: The requested privilege"""

    def validate(func, self, *args, **kwargs):
        """Validator of needs_privillige"""
        try: check(self.user, privilege, project)
        except AccessDenied:
            return abort(status_code=401)
        else:
            return func(self, *args, **kwargs)
    validate.privelege = privelege
    return decorator(validate)

顺便说一句，你的装饰师应该是这样的：

def needs_privilege(privilege, project=None):
    def validate(func):
        def new_func(self, *args, **kwargs):
            try: 
                check(self.user, privilege, project)
            except AccessDenied:
                return abort(status_code=401)
            else:
                return func(self, *args, **kwargs)
        new_func.privilege = privilege
        return new_func
    return validate

---

函数也是可以具有属性的对象。您可以在装饰器中设置属性。下面是一个例子：

def needs_privilege(privilege, project=None):
    """Check whether the logged-in user is authorised based on the
    given privilege

    @type privilege: Privilege object, id, or str
    @param privilege: The requested privilege"""

    def validate(func, self, *args, **kwargs):
        """Validator of needs_privillige"""
        try: check(self.user, privilege, project)
        except AccessDenied:
            return abort(status_code=401)
        else: 
            return func(self, *args, **kwargs)

    return decorator(validate)

class TestClass(object):
    def needs_privilege(privilege, project=None):
        def wrapper(func):
            def validate(self, *args, **kwargs):
                """Validator of needs_privillige"""
                print 'validator check for %s' % privilege
                return func(*args, **kwargs)
            validate.privilege = privilege
            return validate

        return wrapper

    @needs_privilege("foo")
    def bar():
        print "called"

>>> test.TestClass().bar()
validator check for foo
called
>>> test.TestClass.bar.privilege
'foo'
>>> test.TestClass().bar.privilege
'foo'

---

如果不需要

decorator

模块，您的问题会简单得多。 如果您不严格需要

decorator

模块，您可以这样编写decorator：

 @needs_privilege("some_privilege")
 def some_function():
     pass

def needs_privilege(privilege, project=None):
    def validate(func):
        def _validate(self, *args, **kwargs):
            return func(self, *args, **kwargs)
        _validate.decorator_args=(privilege,project)
        return _validate
    return validate

@needs_privilege("some_privilege")
def some_function(self):
    pass

a = some_function
print(a.decorator_args)
# ('some_privilege', None)

---

感谢您的回复！但不完全是我想要的。我想在不执行实际函数的情况下将参数传递给needs_privilege（在这个场景中是某个_函数）。谢谢，但这不是我想要的，抱歉。我想在不实际执行函数的情况下检索“privilege”。请看我的编辑。+1我正想办法说同样的话。decorator包增加了问题的复杂性。谢谢！很遗憾，我只能选择一个答案作为解决方案。有几个人提出了基本相同的答案，但不清楚的是您是否需要decorator包（使用

decorator（validate）

）。这是要求吗？不，这不是要求。我的问题在这个帖子中得到了回答（见下文）。谢谢大家！谢谢你的回答！就像我对unutbu所说的，很遗憾我只能选择一个答案！