Return the cached file name for a bucket path file

def _get_cached_file_name(bucket_name, saltenv, path):
    '''
    Return the cached file name for a bucket path file
    '''

    file_path = os.path.join(_get_cache_dir(), saltenv, bucket_name, path)

    # make sure bucket and saltenv directories exist
    if not os.path.exists(os.path.dirname(file_path)):
        os.makedirs(os.path.dirname(file_path))

    return file_path