如何评估从装饰器的包装器中调用的函数的参数？

Question

在装饰器的require_registered包装器中，如何检查“ John”是否在注册用户中？

def require_registered(some_function):

    def wrapper(*args, **kwargs):

        if username_parameter_from_login_function in registered_users: #how to replace "username_parameter_from_login_function"?
            some_function(*args, **kwargs)
        else:
            print("User is not registed")

    return wrapper

@require_registered
def login(username):
    print(username + ' has been logged in')

login('John')

Answer 1

您还应该定义wrapper函数以将username作为参数：

def wrapper(username, *args, **kwargs):
    if username in registered_users:
        some_function(username, *args, **kwargs)
    else:
        print("User is not registed")