backup_to_zip.py

#! python3
# backup_to_zip.py - copies an entire folder and its contents
# to a zip file whose filename increments

import zipfile, os

def backup_to_zip(folder):
    # backup the entire contents of "folder" into a ZIP file.

    folder = os.path.abspath(folder)  # make sure folder is absolute

    # figure out what filename this code should use
    # based on what files already exist
    number = 1
    while True:
        zipFilename = os.path.basename(folder) + '_' + str(number) + '.zip'
        if not os.path.exists(zipFilename):
            break
        number = number + 1

    # create the ZIP file
    print('Creating %s...' % (zipFilename))
    backupZip = zipfile.ZipFile(zipFilename, 'w')

    # Walk the entire folder tree and compress the files in each fodler
    for foldername, subfolders, filenames in os.walk(folder):
        print('Adding files in %s...' % (foldername))
        # Add the current folder to the ZIP file
        backupZip.write(foldername)

        # Add all the files in this folder to the ZIP file.
        for filename in filenames:
            newBase / os.path.basename(folder) + '_'
            if filename.startswith(newBase) and filename.endswith('.zip')
                continue    # Don't backup the backup ZIP files.
            backupZip.write(os.path.join(foldername, filename))
    backupZip.close()
    print('Done.')