[Pkg-utopia-maintainers] Bug#936371: dbus-python: Python2 removal in sid/bullseye

[Simon McVittie]

On Mon, 27 Jul 2020 at 17:18:03 +0100, peter green wrote:
> On 27/07/2020 16:31, smcv at debian.org wrote:
> > - revert the removal of python-dbus, but drop the python-gi B-D
> >    and the python-gi dependency of the python2 autopkgtest
> >    (test coverage will be reduced, and python-dbus will be of
> >    limited practical use)
> 
> What exactly do you mean by "limited practical use", what are the
> consequences of running jackd2 with python-dbus installed but
> python-gi not installed (I notice that python-dbus recommends
> python-gi)

With a main loop (provided by python-gi, PyQt or some Enlightenment-related
library, but most commonly python-gi), python-dbus can call D-Bus methods
synchronously (blocking) or asynchronously (non-blocking), listen for
D-Bus signals, and export D-Bus objects.

Without a main loop, it can call methods synchronously, and that's all
(similar to dbus-send(1) but in Python).

It looks as though jackd2 only uses python(3)-dbus for
https://sources.debian.org/src/jackd2/1.9.14%7Edfsg-0.1/example-clients/jack_control/
which seems to only be using synchronous method calls anyway, so a cut-down
python-dbus without the python-gi bits would probably be sufficient.

If Raspbian is a bullseye derivative, and if I'm understanding its reason
for the dependency correctly, another way to address this would be to
drop the /usr/bin/jack_control example program and the python-dbus
dependency from a Raspbian-patched version of bullseye's jackd2.

> > - revert the removal of python-gi (revert pygobject 3.36.0-4)
> 
> I went with this approach in raspbian, it turned out not to be as simple
> as a revert though.

That's because the maintainers of pycairo already noticed that python-gi
had been dropped, and took the opportunity to remove python-cairo-dev, one
more step down the dependency chain.

    smcv