Question

我们说我有以下代码，另外还有10个代码。

try:
   session.get('http://www.google.com')
except rex.MissingSchema as e:
    raise RESTClientException('Bad URL for request: ' + str(url), 'error:url', e)
except rex.ConnectionError as e:
    raise RESTClientException('Cannot connect for token', 'error:connection', e)
except rfcex.InsecureTransportError as e:
    raise RESTClientException('Verify certificates True without https', 'error:https', e)

让我们说我想在多个功能中使用所有这些，除了它们，它们究竟是怎样的。我能想到的唯一方法就是：

try:
    session.get('http://www.google.com')
except Exception as e:
    interpret_exception(e)

def interpret_exception(e)
    if isinstance(e, rex.MissingSchema):
        raise RESTClientException('Bad URL for request: ' + str(url), 'error:url', e)
    elif isinstance(e, rex.ConnectionError):
        raise RESTClientException('Cannot connect for token', 'error:connection', e)
    #etc...

有更好的方法吗？感谢

Answer 1

我使用装饰器将某些类型的已知异常（可能在函数中发生）包装到另一个异常类型中。目标是为客户端代码提供一个除之外的的异常类型。这可能会帮助您优雅地为每个函数重新提升RESTClientException，如果这是您主要追求的。但是它不会转换任何错误消息。（也许这对你来说更重要，因为原始信息不够清晰！？）

def wrap_known_exceptions(exceptions_to_wrap, exception_to_raise): """Wrap a tuple of known exceptions into another exception to offer client code a single error to try/except against. Args: exceptions_to_wrap (instance or tuple): Tuple of exception types that are caught when arising and wrapped. exception_to_raise (Exception type): Exception that will be raised on an occurence of an exception from ``exceptions_to_wrap``. Raises: exception_to_raise's type. """ def closure(func): @wraps(func) def wrapped_func(*args, **kwargs): try: return func(*args, **kwargs) except exceptions_to_wrap as exception_instance: msg = u"wraps {0}: {1}" msg = msg.format(type(exception_instance).__name__, exception_instance) raise exception_to_raise(msg) return wrapped_func return closure

以下是它的使用方法：

class RESTClientException(Exception): """RESTClientException""" @wrap_known_exceptions(ValueError, RESTClientException) # could also be a tuple def test(): raise ValueError("Problem occured") test()

输出：

Traceback (most recent call last): File "C:/symlinks/..../utilities/decorators.py", line 69, in <module> test() File "C:/symlinks/..../utilities/decorators.py", line 32, in wrapped_func raise exception_to_raise(msg) __main__.RESTClientException: wraps ValueError: Problem occured

Python - 将异常捕获视为通用函数的简单方法

1 个答案: