如何让装饰器从装饰函数访问变量

Question

我正在使用通用的Python超时装饰器。我希望装饰器从它正在装饰的函数中访问变量。在此示例中，我希望消息从准备函数传递到超时函数。我不想使用全局变量，因为这听起来像是不好的做法。

def timeout(seconds):
    def decorator(func):
        def _handle_timeout(signum, frame):
            # Do something with variable message
            print("Sending the message didn't work!")
            print(message)
        def wrapper(*args, **kwargs):
            signal.signal(signal.SIGALRM, _handle_timeout)
            signal.alarm(seconds)
            try:
                result = func(*args, **kwargs)
            finally:
                signal.alarm(0)
            return result
        return wraps(func)(wrapper)
    return decorator
@timeout(5)
def prepare(message):
    """Deploy app using Heroku to the MTurk Sandbox."""
    print("Preparing to send message!")
    send(message)

Answer 1

将处理程序推送到包装器中，以便它有权访问该变量。

from functools import wraps
import signal
import time
def timeout(seconds):
    def decorator(func):
        def wrapper(message, *args, **kwargs):
            def _handle_timeout(signum, frame):
                # Do something with variable message
                print("Sending the message didn't work!")
                print(message)
            signal.signal(signal.SIGALRM, _handle_timeout)
            signal.alarm(seconds)
            try:
                result = func(message, *args, **kwargs)
            finally:
                signal.alarm(0)
            return result
        return wraps(func)(wrapper)
    return decorator
@timeout(1)
def prepare(message):
    # Uncomment to force error
    # time.sleep(3)
    """Deploy app using Heroku to the MTurk Sandbox."""
    print("Preparing to send message!")
    print(message)

if __name__ == "__main__":
    prepare("hi")