[Tutor] catching any exception?

[BELSEY, Dylan]

Hi Lance,
	I have been working on something similar to catch all the exceptions
from a python script file that the user creates.  It initially checks for
some particular exception types that I know could be raised and the final
clause is a catch-all for any exceptions that are not accounted for such as
syntax errors in the script.  It makes use of the "traceback" module,
obtains a trace of the latest exception and sends the info to an error
logger as a single line.  From the code it is obvious that this is embedded
within a class and makes use of other objects, but I hope that the ideas and
logic are clear.
	Anyway, I'm not sure how relevant it will be for you but I have
posted the code below.  Hope you can make use of it.

		Dylan.

PS: Using Python 2.1.1

# Code begins:

import sys, traceback, string

# Capture the latest stack trace for an exception.
# Use a function to avoid a circular reference problem in Python.
# Refer: http://www.python.org/doc/current/lib/module-sys.html
# for further information.
# INPUT: None.
# OUTPUT: List of strings containing the error.
def ObtainTrace(self):
    # "Thread-safe" capture of the exception.
    excType, excValue, excTraceback = sys.exc_info()
                    
    # Format the most recent stack trace and info. for exceptions.
    Trace = traceback.format_exception(excType, excValue, excTraceback,
None)

    # Delete the traceback object to avoid causing a circular reference
problem.
    del excTraceback

    return Trace



# Capture the exception if the script file is in error.
try:
    execfile(self.ScriptFile)
                        
except exceptions.TypeError, errMsg:
    # Don't really need to specify the "exceptions" class in the line above.
    # Handle this exception....

except: # For syntax and other errors in the file.
    # Create the error message.
	
    # Capture the latest exception.
    TraceList = self.ObtainTrace()

    # Extract important lines into a string.
    # refer to traceback doco for more info here.
    if len(TraceList) > 3:
        lines = TraceList[2] + TraceList[3]
    else:
        lines = ''.join(TraceList)       # Whole stack trace.

    # Replace newlines with a full-stop and a space.
    errMsg = string.replace(lines, '\n', '. ')
    
    EMessage = """Exception in script file: %s"""%(errMsg)
 
    # Send to the logger.
    self.ErrorHandler.Capture(ErrorLogWindow.UI_SCRIPT_OP_ERROR, EMessage)
    
    # Set the file path string to None so that the error does not repeat.
    self.ScriptFile = None


# Code ends.