Re: Bug#811036: wireshark-qt: aborts immediately

[Bálint Réczey <balint@balintreczey.hu>]

Hi Olaf,

2016-01-15 10:28 GMT+01:00 Olaf Meeuwissen <olaf.meeuwissen@avasys.jp>:
>
> Bálint Réczey writes:
>
>> Hi Olaf,
>>
>> 2016-01-15 5:51 GMT+01:00 Olaf Meeuwissen <olaf.meeuwissen@avasys.jp>:
>>> Package: wireshark-qt
>>> Version: 2.0.0+g9a73b82-1
>>> Severity: grave
>>>
>>> Dear Maintainer,
>>>
>>> I tried starting wireshark from the comman-line and it immediately
>>> aborted.  Like so:
>>>
>>>   $ wireshark
>>>   This application failed to start because it could not find or load the Qt platform plugin "xcb".
>>>
>>>   Available platform plugins are: linuxfb, minimal, minimalegl, offscreen.
>>>
>>>   Reinstalling the application may fix this problem.
>>>   Aborted
>>>
>>> I had expected it to start like it used to do.  I don't recall when I
>>> last used it.  I keep my system up-to-date with unattended-upgrades and
>>> my logs indicate wireshark-qt was installed on 2015-12-01 with the
>>> upgrade of wireshark from 1.12.8+g5b6e543-2 to 2.0.0+g9a73b82-1.  I do
>>> remember being surprised at the changed look-and-feel of wireshark, so I
>>> am pretty sure that I have run wireshark-qt successfully in the past.
>
>> Please install libqt5xcbqpa5 to let it run again.
>>
>> I suspect you installed wireshark/libqt5gui5 with --no-install-recommends,
>> since libqt5gui5 recommends libqt5xcbqpa5:
>
> Almost, I ran unattended-upgrade and my apt.conf has
>
>   APT::Install-Recommends              "false";
>   Apt::AutoRemove::RecommendsImportant "false";
>   Unattended-Upgrade::Remove-Unused-Dependencies "true";
>
>> Package: libqt5gui5
>> Source: qtbase-opensource-src
>> Version: 5.5.1+dfsg-12
>> Installed-Size: 7096
>> Maintainer: Debian Qt/KDE Maintainers <debian-qt-kde@lists.debian.org>
>> Architecture: amd64
>> ...
>> Recommends: libqt5svg5, libqt5xcbqpa5
>>
>> --no-install-recommends may cause parts of functionality not available
>> in packages.
>
> Well, in this case *all* of the functionality was not available.  The
> wireshark executable is the only thing in /usr/bin/ of wireshark-qt.
>
>> It that was the case, please close the bug since the default behavior
>> of installing all
>> needed packages for proper operation was overridden.
>
> I think we have different opinions on what is "needed" for proper
> operation.  From Debian Policy, section 7.2 under `Depends`:
>
>   The `Depends` field should be used if the depended-on package is
>   required for the depending package to provide a significant amount
>   of functionality.
>
> I would argue that showing the GUI is a prerequisite for any of the
> functionality.  The GUI isn't shown, hence, zero functionality.
It still had wireshark manpage which is not present in wireshark-gtk and
can be useful, but I see your point. :-)

> I don't know how wireshark-qt obtained the dependency but it needs that
> xcb plugin very badly to provide any functionality.  Can't you add the
> libqt5xcbqpa5 dependency to wireshark-qt (even if only temporarily)?
I can, but fixing that a fixed libqt5gui5 would reach testing as fast a
fix in wireshark-qt, thus I would like to as KDE Maintaintainers to share
their thoughts first.

IMO packages should not follow how Qt packages are structured to set
their dependencies, but Qt should provide helper scripts which set the
needed dependencies for the binary packages. Many other frameworks
do that.

If the KDE team still decides to split the packages with no helper scripts,
please coordinate with reverse dependencies in advance to avoid bugs
like this one.

Cheers,
Balint