Python异常捕捉traceback.format_exc()

test.py
import traceback
import requests

def f():
        try:
                requests.get('http://1.1.1.1', timeout=0.1)
        except:
                print(traceback.format_exc(limit=2, chain=False))


if __name__ == '__main__':
        print(123)
        f()
        print(456)

输出：

123
Traceback (most recent call last):
    File "D:/software/work/code/test/traceback_test.py", line 13, in f
        requests.get('http://1.1.1.1', timeout=0.1)
    File "D:\software\work\code\test\venv\lib\site-packages\requests\api.py", line 72, in get
        return request('get', url, params=params, **kwargs)
requests.exceptions.ConnectTimeout: HTTPConnectionPool(host='1.1.1.1', port=80): Max retries exceeded with url: / (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x00000216B10256A0>, 'Connection to 1.1.1.1 timed out. (connect timeout=0.1)'))

456


test2.py
import traceback
import requests

def f():
        try:
                requests.get('http://1.1.1.1', timeout=0.1)
        except:
                print(traceback.format_exc(limit=1, chain=False))


if __name__ == '__main__':
        print(123)
        f()
        print(456)

输出
123
Traceback (most recent call last):
    File "D:/software/work/code/test/traceback_test.py", line 13, in f
        requests.get('http://1.1.1.1', timeout=0.1)
requests.exceptions.ConnectTimeout: HTTPConnectionPool(host='1.1.1.1', port=80): Max retries exceeded with url: / (Caused by ConnectTimeoutError(<urllib3.connection.HTTPConnection object at 0x0000012A61875630>, 'Connection to 1.1.1.1 timed out. (connect timeout=0.1)'))

456

import threading
import traceback

def my_func():
        raise BaseException("thread exception")


class ExceptionThread(threading.Thread):

        def __init__(self, group=None, target=None, name=None, args=(), kwargs=None, verbose=None):
                """
                Redirect exceptions of thread to an exception handler.
                """
                threading.Thread.__init__(self, group, target, name, args, kwargs, verbose)
                if kwargs is None:
                        kwargs = {}
                self._target = target
                self._args = args
                self._kwargs = kwargs
                self._exc = None

        def run(self):
                try:
                        if self._target:
                                self._target()
                except BaseException as e:
                        import sys
                        self._exc = sys.exc_info()
                finally:
                        #Avoid a refcycle if the thread is running a function with
                        #an argument that has a member that points to the thread.
                        del self._target, self._args, self._kwargs

        def join(self):
                threading.Thread.join(self)
                if self._exc:
                        msg = "Thread '%s' threw an exception: %s" % (self.getName(), self._exc[1])
                        new_exc = Exception(msg)
                        raise new_exc.__class__, new_exc, self._exc[2]


t = ExceptionThread(target=my_func, name='my_thread')
t.start()
try:
        t.join()
except:
        traceback.print_exc()

输出：
Traceback (most recent call last):
    File "/data/code/testcode/thread_exc.py", line 43, in <module>
        t.join()
    File "/data/code/testcode/thread_exc.py", line 23, in run
        self._target()
    File "/data/code/testcode/thread_exc.py", line 5, in my_func
        raise BaseException("thread exception")
Exception: Thread 'my_thread' threw an exception: thread exception