configuration GUI error when clearing "Minimum size under which backup is considered failed" value

[GuitarBilly]

npbackup 3.0.2-dev-linux-gui-x64-legacy-public-3.10-i 2025040401
Ubuntu 22.04.2 LTS

( i was trying to reset the value in the assumption that the Group inherited value would appear instead of the current Repo value. )

steps to reproduce

1. open configuration

2. select a repo

3. empty the box with value "Minimum size under which backup is considered failed"
   

4. select any Repo in the "select configuration object" dropdown box
   

5. enjoy the error:
   

after pressing OK npbackup-gui will crash and exit:

2025-04-16 18:28:27,931 :: INFO :: Launching configuration GUI
2025-04-16 18:31:27,887 :: CRITICAL :: GUI Execution error Given string "" cannot be converted to bytes
2025-04-16 18:31:27,887 :: INFO :: Trace:
Traceback (most recent call last):
  File "/home/linux/npbackup.latest.github/npbackup/npbackup/gui/__main__.py", line 1274, in main_gui
    _main_gui(viewer_mode=viewer_mode)
  File "/home/linux/npbackup.latest.github/npbackup/npbackup/gui/__main__.py", line 1168, in _main_gui
    full_config = config_gui(full_config, config_file)
  File "/home/linux/npbackup.latest.github/npbackup/npbackup/gui/config.py", line 2449, in config_gui
    full_config = update_config_dict(
  File "/home/linux/npbackup.latest.github/npbackup/npbackup/gui/config.py", line 846, in update_config_dict
    == BytesConverter(value).bytes
  File "/home/linux/npbackup.latest.github/npbackup/venv/lib/python3.10/site-packages/ofunctions/misc/__init__.py", line 404, in __new__
    raise ValueError(
ValueError: Given string "" cannot be converted to bytes
2025-04-16 18:31:27,900 :: INFO :: ExecTime = 0:11:42.576405, finished, state is: critical.

expected behaviour

npbackup to not crash, restore the value enherited from the group setting, or provide a warning / error that it is not allowed to clear the box.

[deajan]

Thank you for the report.
Fixed in current master.

Current GUI implementation is not programmer friendly anymore:

• GUI Framework shifted to close source, so NPBackup switched to a fork, which doesn't get much development
• GUI Framework is adapted for small projects, the config GUI is quite a mess to maintain
• Inheritance code itself is nice (and allows inheritance between different object classes), but getting to know what was inherited via GUI is not simple, and that's where the culprit was

So I will maintain and make the current GUI as good as it gets, but will later switch to something more adapted, where widgets don't burn you like this one.
Don't hesitate to open other issues if needed.