像Python一样格式化异常

Question

如果我在Python中引发异常,这就是我得到的:

raise Exception("Hello world")
Traceback (most recent call last):

  File "<ipython-input-24-dd3f3f45afbe>", line 1, in <module>
    raise Exception("Hello world")

Exception: Hello world

注意最后一行说的Exception: Hello world.给定Exception(foo = Exception("Hello world")),我该如何生成这样的文本？以下工作均不属于:

str(foo)
Out[27]: 'Hello world'

repr(foo)
Out[28]: "Exception('Hello world',)"

"{}".format(foo)
Out[29]: 'Hello world'

"{}: {}".format(type(foo), foo)
Out[30]: "<type 'exceptions.Exception'>: Hello world"

Answer 1

如果你的异常对象是exc,那么:

• 结肠前的部分是type(exc).__name__.
• 结肠后的部分是str(exc).

所以你可以这样做:

print('{}: {}'.format(type(exc).__name__, exc))

Answer 2

使tdelaney的回答正式化并证明与众不同...

弦乐

#test.py
import traceback

try :
    raise TypeError("Wrong Type baby!")

except Exception, e:
    print( "EXCEPTION FORMAT PRINT:\n{}".format( e ) )
    print( "EXCEPTION TRACE  PRINT:\n{}".format( traceback.format_exc(e) ) )

结果控制台输出

EXCEPTION FORMAT PRINT:
Wrong Type baby!
EXCEPTION TRACE  PRINT:
Traceback (most recent call last):
  File "/Users/me/test.py", line 4, in <module>
    raise TypeError("Wrong Type baby!")
TypeError: Wrong Type baby!

记录中

如果您处于日志记录的环境中，那么还有异常方法和exc_infokwarg将为您进行格式化。我们应该注意，由于root logger将警告作为其默认日志级别，因此忽略了debug和info级别的日志消息。

# logTest.py
import logging

try :
    raise ValueError("my bad value")
except Exception as e :
    logging.exception( e )
    logging.debug("\n{}\nDEBUG LEVEL EXAMPLE".format('-'*30), exc_info=e)
    logging.info("\n{}\nINFO LEVEL EXAMPLE".format('-'*30), exc_info=e)
    logging.warning("\n{}\nWARNING LEVEL EXAMPLE".format('-'*30), exc_info=e)
    logging.error("\n{}\nERROR LEVEL EXAMPLE".format('-'*30), exc_info=e)

与最终的控制台输出...

ERROR:root:my bad value
Traceback (most recent call last):
  File "/Users/me/logTest.py", line 5, in <module>
    raise ValueError("my bad value")
ValueError: my bad value
WARNING:root:
------------------------------
WARNING LEVEL EXAMPLE
Traceback (most recent call last):
  File "/Users/me/logTest.py", line 5, in <module>
    raise ValueError("my bad value")
ValueError: my bad value
ERROR:root:
------------------------------
ERROR LEVEL EXAMPLE
Traceback (most recent call last):
  File "/Users/me/logTest.py", line 5, in <module>
    raise ValueError("my bad value")
ValueError: my bad value