topic ErrorDesc versus Err as exception in Python Snippets Questions

ErrorDesc versus Err as exception

JoeBorgione — Sun, 12 Dec 2021 08:34:12 GMT

I've been tasked with updating a number of scripts that we run over night as scheduled tasks. The original scripts use several try: except blocks that look like this:

if arcpy.Exists(gdbPathNameTestBAK):   
    try:
        arcpy.Delete_management(gdbPathNameTestBAK)
        print "Success: Deleted BACKUP  " + gdbPathNameTestBAK
    except Exception, ErrorDesc:
        errorFlag = True
        EmailNoticeDeleteBack = "Error: No Delete BACKUP " + gdbPathNameTestBAK
        print str(ErrorDesc) + "Error: No Delete BACKUP " + gdbPathNameTestBAK
# note the except Exception, ErrorDesc:


EmailNoticeExportXML = ""  
try:
    arcpy.ExportXMLWorkspaceDocument_management(sdePathName, xmlWorkspacePath, "SCHEMA_ONLY", "BINARY", "NO_METADATA")
    print "Success: Exported XML workspace to " + xmlWorkspacePath
except Exception, Err:
    errorFlag = True
    EmailNoticeExportXML =  "Error: No Export XML workspace to " + xmlWorkspacePath
    print str(Err) + " Error: No Export XML workspace to " + xmlWorkspacePath
#note the except Exception Err:‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

My question is in regards to the except arguments. What's the difference between ErrorDesc and Err? Also, I've changed the the print statements to :

###original --print str(ErrorDesc) + "Error: No Delete BACKUP " + gdbPathNameTestBAK
#mine:
print'{} Error: No Delete BACKUP'.format(gdbPathNameTestBAK)

### original -- print str(Err) + " Error: No Export XML workspace to " + xmlWorkspacePath
#mine:
print '{} Error: No Export XML workspace to'.format(xmlWorkspacePath)‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

After running the print statements I drop the str() method as it does not seem to make a difference. Thoughts there?

Re: ErrorDesc versus Err as exception

DanPatterson_Retired — Thu, 21 Jun 2018 23:59:52 GMT

Joe... I think your ErrDesc is the equivalent to 'e' in this example (and in the python docs)

Difference between except: and except Exception as e: in Python - Stack Overflow

and fancy-schmancy format strings that you are now using, automatically convert anything that has a string representation to a string. Some objects … like our favorite... None will show as NoneType

Re: ErrorDesc versus Err as exception

JoeBorgione — Fri, 22 Jun 2018 02:34:43 GMT

Hahaha- 'fancy-schmancy'?! I learned them from you!

Re: ErrorDesc versus Err as exception

JoeBorgione — Sun, 12 Dec 2021 08:34:14 GMT

As an after thought, these are all in Python 2.x scripts; I notice when I plug the the try-except blocks into Python 3.x in a Spyder IDE, it will complain if you don't use:

try:
    #some code that may throw an exception
except Exception as e:
    #exception handling code
#### Note the as e reference####‍‍‍‍‍