How can I print the traceback and exception of a zmq.REQ worker?

Question

I'm using pexpect.spawn to write some script that can run in parallel.

But I found that the traceback and exception of a zmq.REQ worker won't be printed out in the terminal where I run the master.py (zmq.REP).

I know sys.stderr can be used to redirect the traceback and exception, but I have no idea how should I use this in the worker.py so that the exceptions happen in worker.py can be printed out.

Answer 1

Use logging.exception and log into a file.

Example:

import logging

logging.basicConfig(filename='example.log') 


def fail():
    return 10/0

try:
    fail()
except Exception as err:
    loggin.exception(err)

Output (example.log) :

ERROR:root:integer division or modulo by zero
Traceback (most recent call last):
  File "<ipython-input-4-d63f4b56d991>", line 2, in <module>
    fail()
  File "<ipython-input-3-edce7c179301>", line 2, in fail
    return 10/0
ZeroDivisionError: integer division or modulo by zero