如何将捕获的异常(其描述和堆栈跟踪)转换为外部使用的str ?

try:
    method_that_can_raise_an_exception(params)
except Exception as e:
    print(complete_exception_description(e))

当前回答

如果你想将你的回溯转换为dict的列表(适用于python > 3.5):

from traceback import TracebackException


def list_traceback(exc_value: BaseException):
    result = list()

    # get previous fails, so errors are appended by order of execution
    if exc_value.__context__:
        result += list_traceback(exc_value.__context__)

    # convert Exception into TracebackException
    tbe = TracebackException.from_exception(exc_value)

    # get stacktrace (cascade methods calls)
    error_lines = list()
    for frame_summary in tbe.stack:
        summary_details = {
            'filename': frame_summary.filename,
            'method'  : frame_summary.name,
            'lineno'  : frame_summary.lineno,
            'code'    : frame_summary.line
        }
        error_lines.append(summary_details)

    # append error, by order of execution
    result.append({"error_lines": error_lines,
                   "type"       : tbe.exc_type.__name__,
                   "message"    : str(tbe)})

    return result

这将是结果(一个例子):

[
   {
      "error_lines": [
         {
            "filename": "/home/demo/file2.py",
            "method": "do_error_2",
            "lineno": 18,
            "code": "a=1/0"
         }
      ],
      "type": "ZeroDivisionError",
      "message": "division by zero"
   },
   {
      "error_lines": [
         {
            "filename": "/home/demo/file_main.py",
            "method": "demo2",
            "lineno": 50,
            "code": "file2.DEMO().do_error_2()"
         },
         {
            "filename": "/home/demo/file2.py",
            "method": "do_error_2",
            "lineno": 20,
            "code": "raise AssertionError(\"Raised inside the except, after division by zero\")"
         }
      ],
      "type": "AssertionError",
      "message": "Raised inside the except, after division by zero"
   }
]

其他回答

>>> import sys
>>> import traceback
>>> try:
...   5 / 0
... except ZeroDivisionError as e:
...   type_, value_, traceback_ = sys.exc_info()
>>> traceback.format_tb(traceback_)
['  File "<stdin>", line 2, in <module>\n']
>>> value_
ZeroDivisionError('integer division or modulo by zero',)
>>> type_
<type 'exceptions.ZeroDivisionError'>
>>>
>>> 5 / 0
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ZeroDivisionError: integer division or modulo by zero

您可以使用sys.exc_info()收集信息,并使用traceback模块中的函数对其进行格式化。 下面是一些格式化的例子。

整个异常字符串位于:

>>> ex = traceback.format_exception(type_, value_, traceback_)
>>> ex
['Traceback (most recent call last):\n', '  File "<stdin>", line 2, in <module>\n', 'ZeroDivisionError: integer division or modulo by zero\n']

对于Python 3.5+ 使用回溯。TracebackException,它可以处理在任何地方捕获的异常。

def print_trace(ex: BaseException):
    print(''.join(traceback.TracebackException.from_exception(ex).format()))

例子

import traceback

try:
    1/0
except Exception as ex:
    print(''.join(traceback.TracebackException.from_exception(ex).format()))

> >输出

Traceback (most recent call last):
  File "your_file_name_here.py", line 29, in <module>
    1/0
ZeroDivisionError: division by zero

它与from_exec()和format_exception()相同:

    a = ''.join(traceback.TracebackException.from_exception(ex).format())
    b = traceback.format_exc()
    c = ''.join(traceback.format_exception(type(ex), ex, ex.__traceback__))
    print(a == b == c)  # This is True !!

我的2美分。

import sys, traceback
try: 
  ...
except Exception, e:
  T, V, TB = sys.exc_info()
  print ''.join(traceback.format_exception(T,V,TB))

请参阅traceback模块,特别是format_exc()函数。在这里。

import traceback

try:
    raise ValueError
except ValueError:
    tb = traceback.format_exc()
else:
    tb = "No error"
finally:
    print tb

如果您希望在未处理异常时获得相同的信息,可以这样做。执行import trace,然后:

try:
    ...
except Exception as e:
    print(traceback.print_tb(e.__traceback__))

我使用的是Python 3.7。