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How to handle the unexpected

Thanks to a french blog, I just discovered that python allow you to handle the unexecpected python errors.
It is called "excepthook" and it is a must have in a studio framework !
So I urged myself to put a routine into the of anyone in the studio that starts Maya or MotionBuilder:

import sys

def handleCrash(_ErrorType, _Value, _TraceBack):
  """ do your stuff """
  sys.__excepthook__(_ErrorType, _Value, _TraceBack) #as Sam says, be polite.

sys.excepthook = handleCrash
With that, you can send you an email with a HTML-formated text, with all the details, but be careful about the possible lag when sending email.
My best guest right now is to insert an sql request into a debug.db file using sqlite3.
With a little additional efforts (or a database reading app), you can track anything happening in the studio.
My advice is to get exact time, the user name, machine name and its opened-file's name to fill the logging.
Here is the final snippet:

import sys

def handleCrash(_ErrorType, _Value, _TraceBack):
  import traceback
  import sys
  import datetime
  import os

  UserName = os.getenv('USERNAME')
  MachineName = os.getenv('COMPUTERNAME')

  FileName = "" # could be, regarding your current environment,

  HtmlBuffer+="UNEXPECTED:"+str(_ErrorType) +" ==> "+ str(_Value)+"<br>"
  HtmlBuffer+= UserName+" on "+MachineName+"<br>"
  HtmlBuffer+= "on File ="+FileName+"<br>"

  dt =
  DateNiceName = dt.strftime("%A, %d. %B %Y %I:%M%p")
  HtmlBuffer+= "At "+DateNiceName+"<br>"

  formatted_lines = traceback.format_tb(_TraceBack)
  for cur in  formatted_lines:

  #do your stuff

  sys.__excepthook__(_ErrorType, _Value, _TraceBack)

sys.excepthook = handleCrash

By the way, in Maya you will find that some of your errors will not be caught by that system.
Cyrille Fauvel wrote about that in the awesome "Around the corner" dev blog.
import maya.utils

def handleCrash_Maya(etype, value, tb, detail=2):
handleCrash(etype, value, tb)
  return maya.utils._formatGuiException(etype, value, tb, detail)

maya.utils.formatGuiException = handleCrash_Maya

PS: Coming back from GDC2013, I attended to an awesome conference called "Spend Time Where it Matters: Friction Free Bug Reporting" by Raphael Saint-Pierre (Ubisoft) , talking about auto-BugReporting.
I learned here a very great tips to identify and index a bug into a database without creating some clones of similar ones everytime a new occurence pop. How ? Very easy: give an Id coming from a hash of the call stack ! Tested... and approved !

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