Re-raise different exception with original stack trace

[Prasad, Ramit]

Hi all,
Hopefully you guys can help me with my problem.

Basically I have a UI program that can "save" information. The UI passes the save to the controller and the controller saves a file and does some post processing. If saving the file fails, I want to handle the error differently than if the error was in post processing. In both cases the possible exceptions are varied and unknown so I cannot pick and choose certain exception. The problem with the sample program below is that the stack trace is replaced by the re-raise. What would be the best way(s) to get the original stack trace in save_from_UI if the exception occurs in post_process? Using Python 2.6 and Windows(XP and 7) / Linux.

Def save_from_model():
    save() # do not catch exception (could be any exception)
    try:
        post_process()
    except Exception as e: 
        #do something
        raise CustomException() # "wrap" exception so bar knows to handle it differently

def save_from_UI():
    try:
        foo()
    except CustomException() as e:
        # How do I get the original stacktrace instead of the reraise?
    except Exception as e:
        # do something else with this exception


Ramit


Ramit Prasad | JPMorgan Chase Investment Bank | Currencies Technology
712 Main Street | Houston, TX 77002
work phone: 713 - 216 - 5423



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