【发布时间】:2020-10-15 17:37:05
【问题描述】:
目标脚本
from threading import Thread
import instrument
import sys
args=None
def main():
function1()
def function1():
with open("help11.txt") as f:
print(f.read())
if __name__ == "__main__":
with instrument.FooManager():
t= Thread(target=main)
t.start()
t.join()
上下文管理器定义 Instrument.py
class FooManager(object):
def __init__(self, **kwargs):
self.kwargs = kwargs
def __enter__(self):
self.start_time, self.fmt_start_time = self.__timings()
def __exit__(self, exc_type, exc_value, traceback):
print(exc_type)
print(exc_value)
self.end_time, self.fmt_end_time = self.__timings()
duration = (self.end_time - self.start_time)
print("start_time",self.start_time)
print("end_time",self.end_time)
print("duration",duration)
def __timings(self):
return time.time(),time.strftime('%Y-%m-%d %H:%M %Z', time.gmtime(time.time()))
实际输出
Exception in thread Thread-1:
Traceback (most recent call last):
File "/usr/lib/python3.6/threading.py", line 916, in _bootstrap_inner
self.run()
File "/usr/lib/python3.6/threading.py", line 864, in run
self._target(*self._args, **self._kwargs)
File "test.py", line 10, in main
function1(10000000, 1)
File "test.py", line 14, in function1
with open("help11.txt") as f:
FileNotFoundError: [Errno 2] No such file or directory: 'help11.txt'
None
None
fmt_start_time 1602782848.645685
end_time 1602782848.6461706
duration 0.0004856586456298828
预期输出
我想要的只是使用上下文管理器以某种方式捕获错误,而不是我在 exc_type 和 exc_value 中将值设为 None 或者在上下文管理器中捕获线程引发的错误的推荐方法是什么
注意:当“with 语句”之后没有线程声明时,此代码可以正常工作
【问题讨论】:
-
线程没有引发错误。正如标题“线程 Thread-1 中的异常:”所说,错误只是 inside 线程。
t.start()和 t.join() 都没有向调用线程提供线程t的返回值或异常。你能改变线程有效负载的实现,或者线程是如何创建的吗? -
你能根据上面的情况给我一个例子吗
标签: python multithreading exception contextmanager