implement BACKUPMODE_INCREMENTAL

import sys

import time

import traceback

from typing import Dict, Union

parser = argparse.ArgumentParser(description='tool to synchronize ceph rbd images between two clusters, using ssh', usage='python3 main.py --source username@server:rbd/image_name --destination rbd_backup/backup_test_destination')

    raise RuntimeError('cannot determine ceph snapshot name, aborting!')

def get_backup_mode(from_source, to_destination, command_inject: str = ''):

def get_backup_mode(from_source, to_destination, command_inject: str = '') -> Union[Dict[str, str], Dict[str, str]]:

    source_exists = ceph_rbd_image_exists(from_source['pool'], from_source['image'], command_inject)

    if not source_exists:

        raise RuntimeError('invalid arguments, source image does not exist ' + ceph_rbd_object_to_path(from_source))

        raise RuntimeError('inconsistent state, source snapshot not found but destination does exist')

    if source_previous_snapshot_count == 0 and not destination_exists:

        return {'mode': BACKUPMODE_INITIAL}

        return {'mode': BACKUPMODE_INITIAL, 'base_snapshot': ''}

    else:

        return {'mode': BACKUPMODE_INCREMENTAL, 'base_snapshot': get_previous_ceph_rbd_snapshot_name(from_source['pool'], from_source['image'], command_inject)}

def get_ceph_rbd_properties(pool: str, image: str, command_inject: str = ''):

    return exec_parse_json('rbd -p ' + pool + ' --format json info ' + image, command_inject)

    return exec_parse_json(command_inject + 'rbd -p ' + pool + ' --format json info ' + image)

def set_ceph_scrubbing(enable: bool, command_inject: str = ''):

        create_ceph_rbd_image(destination_pool, destination_image)

        log_message('beginning full copy from ' + ceph_rbd_object_to_path(source) + ' to ' + ceph_rbd_object_to_path(destination), LOGLEVEL_INFO)

        # TODO: start full image copy, using export-diff, to destination

        # ssh $DESTHOST rbd export-diff $SOURCEPOOL/$LOCAL_IMAGE@$TODAY - | rbd import-diff - $DESTPOOL/$LOCAL_IMAGE

        exec_raw(execute_on_remote_command + 'rbd export-diff ' + whole_object_command + source_pool + '/' + source_image + ' - 2>/dev/null | pv --rate --bytes | rbd import-diff - ' + destination_pool + '/' + destination_image + ' 2>/dev/null')

        exec_raw(execute_on_remote_command + 'rbd export-diff ' + whole_object_command + ceph_rbd_object_to_path(source) + ' - 2>/dev/null | pv --rate --bytes | rbd import-diff - ' + ceph_rbd_object_to_path(destination) + ' 2>/dev/null')

        log_message('copy finished', LOGLEVEL_INFO)

        create_ceph_rbd_snapshot(source_pool, source_image, execute_on_remote_command)

        create_ceph_rbd_snapshot(destination_pool, destination_image)

    if mode['mode'] == BACKUPMODE_INCREMENTAL:

        snapshot1 = mode['base_snapshot']

        snapshot2 = create_ceph_rbd_snapshot(source_pool, source_image, execute_on_remote_command)

        snapshot_old = mode['base_snapshot']

        snapshot_new = create_ceph_rbd_snapshot(source_pool, source_image, execute_on_remote_command)

        log_message('beginning incremental copy from ' + ceph_rbd_object_to_path(source) + ' to ' + ceph_rbd_object_to_path(destination), LOGLEVEL_INFO)

        log_message('beginning incremental copy from ' + ceph_rbd_object_to_path(source) + '@' + snapshot_old + ' to ' + ceph_rbd_object_to_path(destination), LOGLEVEL_INFO)

        # TODO: start incremental image copy, using export-diff, to destination

        # TODO: datarate to strderr via command "pv"

        #ssh rbd export-diff --from-snap $YESTERDAY $SOURCEPOOL/$LOCAL_IMAGE@$TODAY - | $DESTHOST rbd import-diff - $DESTPOOL/$LOCAL_IMAGE

        exec_raw(execute_on_remote_command + 'rbd export-diff ' + whole_object_command + ' --from-snap ' + snapshot_old + ' ' + ceph_rbd_object_to_path(source) + '@' + snapshot_new + ' - 2>/dev/null | pv --rate --bytes | rbd import-diff - ' + ceph_rbd_object_to_path(destination) + ' 2>/dev/null')

        log_message('copy finished', LOGLEVEL_INFO)

        create_ceph_rbd_snapshot(destination_pool, destination_image)

        remove_ceph_rbd_snapshot(source_pool, source_image, snapshot, execute_on_remote_command)

        remove_ceph_rbd_snapshot(source_pool, source_image, snapshot_old, execute_on_remote_command)

    log_message(BackgroundColors.OKGREEN + 'Done with ' + ceph_rbd_object_to_path(source) + ' -> ' + ceph_rbd_object_to_path(destination) + BackgroundColors.ENDC, LOGLEVEL_INFO)