Loguru stops TKinter Application from Exiting

[Dominik-3D]

Hi!

First of all - i love loguru, it's a great tool and until now I had zero problem using it. Currently I run into a problem however, i have a fairly complex application that used loguru in multiple places and also multiple threads. In the TKinter UI I want to show the log (at >= Info level). Threfore i create a seperate handle:

self.logger_handler = logger.add(self.add_log_to_gui, colorize=False, level="INFO")

This works fine, until i try to use my _on_closing function

    def _on_closing(self):
        # stop everything
        self._middleware.stop()
        logger.remove(self.logger_handler)
        logger.success("closing application")

        # destroy main frame
        self.destroy()
        self.quit()

The call of the closing function happens when the "X" button in the window is clicked, an that is done by the following code: self.protocol("WM_DELETE_WINDOW", self._on_closing)

The last command in middleware.stop is also executed (which is another logging command) and than nothing more happens. If I remove adding of the logging handler (as shown before) defined for the UI everything works fine and the application closes. I'm not quite sure if the problem is a bug in loguru or if it's just me doing something wrong - if someone has an idea, I would appreciate that.

Thanks, Dominik

[Delgan]

Hi. :)

Would you be able to share a minimal reproducible example please?

It seems Loguru is encountered a dead lock. This can happens if the logger is used inside a __del__ method or a signal handler. However, I don't know exactly what happens in your case with Tkinter.

You can also try to install dev version of Loguru which contains a safety check avoiding deadlock:

pip install git+https://github.com/Delgan/loguru@11951c76d5b2a1bc5809b73b8fd41e804e23a6cc