Question

我正在尝试调试多线程脚本。一旦例外是提出我想：

向监控系统报告（仅在以下示例中打印）
停止整个脚本（包括所有其他线程）
在透视引发异常中调用post mortem调试器提示

我准备了非常复杂的例子来说明我是如何解决它的：

#!/usr/bin/env python

import threading
import inspect
import traceback
import sys
import os
import time


def POST_PORTEM_DEBUGGER(type, value, tb):
    traceback.print_exception(type, value, tb)
    print
    if hasattr(sys, 'ps1') or not sys.stderr.isatty():
        import rpdb
        rpdb.pdb.pm()
    else:
        import pdb
        pdb.pm()

sys.excepthook = POST_PORTEM_DEBUGGER



class MyThread(threading.Thread):

    def __init__(self):

        threading.Thread.__init__(self)
        self.exception = None
        self.info = None
        self.the_calling_script_name = os.path.abspath(inspect.currentframe().f_back.f_code.co_filename)

    def main(self):
        "Virtual method to be implemented by inherited worker"
        return self

    def run(self):
        try:
            self.main()
        except Exception as exception:
            self.exception = exception
            self.info = traceback.extract_tb(sys.exc_info()[2])[-1]
            # because of bug http://bugs.python.org/issue1230540
            # I cannot use just "raise" under threading.Thread
            sys.excepthook(*sys.exc_info())

    def __del__(self):
        print 'MyThread via {} catch "{}: {}" in {}() from {}:{}: {}'.format(self.the_calling_script_name, type(self.exception).__name__, str(self.exception), self.info[2], os.path.basename(self.info[0]), self.info[1], self.info[3])




class Worker(MyThread):

    def __init__(self):
        super(Worker, self).__init__()

    def main(self):
        """ worker job """
        counter = 0
        while True:
            counter += 1
            print self
            time.sleep(1.0)
            if counter == 3:
                pass # print 1/0


def main():

    Worker().start()

    counter = 1
    while True:
        counter += 1
        time.sleep(1.0)
        if counter == 3:
            pass # print 1/0

if __name__ == '__main__':
    main()

sys.excepthook = POST_PORTEM_DEBUGGER

完美地工作。我发现如果是的话多线程脚本我可以通过调用：

rpdb

import rpdb; rpdb.set_trace()

它适用于定义的断点，但我想调试多线程脚本post mortem（在未捕获的异常之后）提高）。当我尝试在POST_PORTEM_DEBUGGER函数中使用rpdb时多线程应用程序我得到以下：

Exception in thread Thread-1:
Traceback (most recent call last):
    File "/usr/lib/python2.7/threading.py", line 552, in __bootstrap_inner
        self.run()
    File "./demo.py", line 49, in run
        sys.excepthook(*sys.exc_info())
    File "./demo.py", line 22, in POST_PORTEM_DEBUGGER
        pdb.pm()
    File "/usr/lib/python2.7/pdb.py", line 1270, in pm
        post_mortem(sys.last_traceback)
AttributeError: 'module' object has no attribute 'last_traceback'

我看起来像

sys.excepthook(*sys.exc_info())

没有设置raise命令的全部内容。如果在main（）中引发异常，我想要相同的行为在启动线程下。

Answer 1

（我没有测试过我的答案，但在我看来......）

对pdb.pm（pm =“post mortem”）的调用失败只是因为之前没有“死亡”。即该程序仍在运行。

查看pdb源代码，您会发现pdb.pm的实现：

def pm():
    post_mortem(sys.last_traceback)

这让我觉得你真正想要做的就是调用pdb.post_mortem()而没有args。看起来默认行为完全符合您的需要。

更多源代码（注意t = sys.exc_info()[2]行）：

def post_mortem(t=None):
    # handling the default
    if t is None:
        # sys.exc_info() returns (type, value, traceback) if an exception is
        # being handled, otherwise it returns None
        t = sys.exc_info()[2]
        if t is None:
            raise ValueError("A valid traceback must be passed if no "
                                               "exception is being handled")

    p = Pdb()
    p.reset()
    p.interaction(None, t)

Answer 2

这可以提供帮助：

import sys
from IPython.core import ultratb

sys.excepthook = ultratb.FormattedTB(mode='Verbose', color_scheme='Linux',
    call_pdb=True, ostream=sys.__stdout__)

事后调试多线程脚本

2 个答案: