Error handling with python script in ArcGIS 10

Question

I have a python script that I am using to create a list of all mxd files (with full pathing) in our Projects folder. The script then uses that to iterate through the list and do a findandreplaceworkspacepaths on each mxd per ESRI's how to. I am running into problems when I hit a corrupted mxd file. The have tried try/except and haven't gotten it to work. The ideal situation would be to write the corrupt filename to a file and move on so I can come back to them at the end. I'm very new with python scripting, any help would be greatly appreciated.

import arcpy, os, sys, traceback, time

oldpath = 'W:'
newpath = 'W:\\GIS'

def find(path,pattern):
    matches = []
    for r,d,f in os.walk(path):
        for files in f:
            if files.endswith(pattern):
                fpath = os.path.join(r,files)
                matches.append(fpath)
                print (fpath)
    return matches


print ("Go: ")
mxdlist = (find('C:\\gis','.mxd'))
print (mxdlist)


print ("Starting Path Conversion")
try:
        for mxdold in mxdlist:
            mxd = arcpy.mapping.MapDocument(mxdold)
            mxd.findAndReplaceWorkspacePaths(oldpath, newpath)
            time.sleep(6)
            mxd.save()
            time.sleep(6)
            print (mxdold)
            del mxd
    except arcpy.ExecuteError:    
        arcpy.AddError(arcpy.GetMessages(2))    

    except:    
        arcpy.AddError("Non-tool error occurred")

Answer 1

First thing to do is bring the top of your for loop outside the try statement. You want to get into your iteration before you give the try statement a chance to kill your operation. Next you'll want to add a few lines to open an error log and write filenames of corrupt files.

import arcpy, os, sys, traceback, time

oldpath = 'W:\\'
newpath = 'W:\\GIS'
cgis_dir = 'C:\\gis'

mxdlist = []

print 'Go: '
files = os.listdir(cgis_dir)
for file in files:
    try:
        if file.split('.')[1] == 'mxd':
            mxdlist.append(file)
            print cgis_dir,file
    except:
        pass


print ("Starting Path Conversion")

for mxdold in mxdlist:
    try:
        mxd = arcpy.mapping.MapDocument(mxdold)
        mxd.findAndReplaceWorkspacePaths(oldpath, newpath)
        time.sleep(6)
        mxd.save()
        time.sleep(6)
        print (mxdold)
        del mxd
    except arcpy.ExecuteError:    
        arcpy.AddError(arcpy.GetMessages(2))
        f=open(r'W:\GIS\error.log','a')
        f.write(mxdold,'\n')
        f.close()

    except:    
        arcpy.AddError("Non-tool error occurred")

Answer 2

This has nothing to do with your error on the corrupt MXDs, but since you are wanting to log, here is a little bare-bones nugget (pretty much straight from the Python docs) using the logging module (as suggested by @om_henners). @sgillies comment above looks excellent as well.

import logging
import datetime
import os

date_tag = datetime.datetime.now().strftime("%Y_%m_%d_%H_%M_%S")
log_file = os.path.join(os.path.dirname(os.curdir), "LogFileTest_%s.log" % date_tag)

# Setup logger
logging.basicConfig(level=logging.DEBUG,
                    format='%(asctime)s %(levelname)-8s %(message)s',
                    datefmt='%Y-%m-%d %H:%M:%S',
                    filename=log_file,
                    filemode='w')
logging.info(': START LOGGING')

try:
    logging.info(": Do something here")
except Exception, err:
    logging.error(": %s" % str(err))

When run as-is, it gives: