QZeitgeist and Phonon

[Alexander Neundorf]

On Tuesday 08 March 2011, John Layt wrote:
> On Monday 07 March 2011 23:58:08 Trever Fischer wrote:
> > Very recently, we introduced an optional build time dependency on
> > QZeitgeist. Today, someone said I should mention this to k-c-d. So here
> > goes:
>
> That was me, I was just concerned we were introducing a new technology and
> library dependency into KDE without a proper understanding of the
> consequences or much awareness of it happening.
>
> The diff for this change can be found at
> https://projects.kde.org/projects/kdesupport/phonon/phonon/repository/diff?
>rev=94af71c5b5542766168594e432086b8cbbd77242&rev_to=b550ea553da5a4722242a3d6
>a453ad6bae34a6d1
>
> > * What is QZeitgeist?
> > A library that neatly wraps the Zeitgeist dbus API with some QObjects.
>
> Has there been a stable release of qzeitgeist yet, or plans to make a
> stable release with a api/abi guarantee?  I see it is in Gitorious, any
> plans to move it to KDE infrastructure or kdesupport and the KDE review
> that would include?
>
> > * Okay, but what is Zeitgeist?
>
> Could you also just touch on why Nepomuk isn't the right tool for this? 
> I'm vaguely aware they are seen as complimentary (afaik Zeigeist == when ,
> Nepomuk == what), but a reminder for those of us not following the semantic
> stuff would be good.  How well do they integrate (if that even makes
> sense)?
>
> > * How does this fit into Phonon?
>
> Just to confirm this is an opt-in setting by the media player itself?  I
> guess the players would need to make it very obvious an option in the api
> as I'm sure there's people who would hate for all their fluffy pink unicorn
> video viewing to get logged ;-)
>
> > 1) It is a new *optional* build-time dependency. If Phonon is compiled
> > with QZeitgeist, but zeitgeist isn't installed, stuff still works. Once
> > zeitgeist is installed, the dbus interfaces work their magic.
>
> So just to confirm the build time dependencies for qzeitgeist itself are
> really only dbus and qt, you don't need Zeitgeist?
>
> What's the runtime footprint of zeitgeist itself?  It appears to have a
> heavy dependency on python, gnome and gobject (at least that's what the
> openSUSE packages require)?  Can it be stripped down to the most basic
> storage layer and api for lighter install and runtime requirements?  Does
> it need yet another storage server to be running?
>
> > 2) The zeitgeist developers (and even the Phonon devs) would absolutely
> > *love* to see more KDE apps use Zeitgeist. Its pretty cool.
>
> Cool indeed, even cooler if its nice and light and we get a KDE front-end
> for it :-)
>
> Could you also drop a line to the kde-buildsystem and kde-packager lists so
> they know of the new requirement?

phonon/CMakeLists.txt:
+ macro_optional_find_package(QZeitgeist)
+ if (QZEITGEIST_INCLUDE_DIR)
+     set(QZEITGEIST_FOUND TRUE)
+ endif(QZEITGEIST_INCLUDE_DIR)

This is not good. QZEITGEIST_FOUND should be set inside FindQZeitgeist.cmake.


+ if (QZEITGEIST_FOUND)
+     target_link_libraries(phonon ${QZEITGEIST_LIBRARY})
+ endif(QZEITGEIST_FOUND)

Does FindQZeitgeist.cmake also define a QZEITGEIST_LIBRARIES variable ? If so, 
this should be used (because it might happen that you need to link more than 
one library to use some library, and then the _LIBRARIES variable will 
contain them all).

Alex