import os
import sys
import shutil
import traceback

def dirEntries(dir_name, subdir, *args):
    '''Return a list of file names found in directory 'dir_name'
    If 'subdir' is True, recursively access subdirectories under 'dir_name'.
    Additional arguments, if any, are file extensions to match filenames. Matched
        file names are added to the list.
    If there are no additional arguments, all files found in the directory are
        added to the list.
    Example usage: fileList = dirEntries(r'H:\TEMP', False, 'txt', 'py')
        Only files with 'txt' and 'py' extensions will be added to the list.
    Example usage: fileList = dirEntries(r'H:\TEMP', True)
        All files and all the files in subdirectories under H:\TEMP will be added
        to the list.
    '''
    fileList = []
    for file in os.listdir(dir_name):
        dirfile = os.path.join(dir_name, file)
        if os.path.isfile(dirfile):
            if not args:
                fileList.append(dirfile)
            else:
                if os.path.splitext(dirfile)[1][1:] in args:
                    fileList.append(dirfile)
        # recursively access file names in subdirectories
        elif os.path.isdir(dirfile) and subdir:
            print "Accessing directory:", dirfile
            fileList.extend(dirEntries(dirfile, subdir, *args))
    return fileList

def updateString(infileName, srchString,rplString):
    bakFileName = os.path.splitext(infileName)[0] + ".bak"
    if not os.path.exists(bakFileName):
        # copy the original file
        shutil.copy(infileName, bakFileName)

    # Open the backup (= original) file to read
    inFileHndl = open(bakFileName,"r")
    outFileHndl = open(infileName,"w")  

    for line in inFileHndl:
        if line.find(searchString) > 0:
            line = line.replace(searchString, replaceString)
        outFileHndl.write(line)
        
    outFileHndl.close()
    inFileHndl.close()
    # remove the backup (=original content file)
    os.remove(bakFileName)

if __name__ == '__main__':

    try:
        inFolder = r"C:\inetpub\wwwroot\viewer"  # path to search
        searchString = "http://mydevserver"      # string to find
        replaceString = "http://mystgserver"     # string - replace searchString with replaceString
        
        fList = dirEntries(inFolder, True, 'xml')
        for f in fList:
            updateString(f, searchString, replaceString)
            
        print '\n\n\n' + 'Process Complete'

    except:
        # Return any python specific errors as well as any errors from the geoprocessor
        #
        tb = sys.exc_info()[2]
        tbinfo = traceback.format_tb(tb)[0]
        pymsg = "PYTHON ERRORS:\nTraceback Info:\n" + tbinfo + "\nError Info:\n    " + \
                str(sys.exc_type)+ ": " + str(sys.exc_value) + "\n"
        print '\n\n\n' + pymsg