Re: libgnomeoffice* plugin management

[David Malcolm <dmalcolm redhat com>]

On Thu, 2005-01-13 at 01:11 +0100, Sven Herzberg wrote:
> Hi,
> 
>   I'm currently looking for plugin system that I can use for my
> presentation application [1]. I took a look at the libgnomeoffice plugin
> system [2] which looks quite nice for me. I had some objections and just
> want to keep them here for discussion, so flame me:
> 
> 1. There hasn't been any release (thus making it hard to add even a
> versioned dependency)
> 
>   not hard to fix
> 
> 2. Plugin definitions are not translatable
> 
>   we should include translation for plugin description in the XML file
> (like we do with GConf schemas) so the library can provide a
> translation.
> 
> 3. There seems to be no definition of a plugin search path but the path
> for xml definitions seems to be hardcoded
> 
>   This makes it quite hard to keep clean systems like /usr being only
> for distribution stuff. I'd like to have a small configuration file (or
> GConf key) so admins/users can specify paths for themselves. The GConf
> solution would make it very easy to have an admin specifying some sane
> defaults and some users can overwrite it for themselves (e.g. I can use
> different plugins as different users, stable ones when showing
> presentations, unstable ones when developing)
> 
> 4. It depends on libgda
> 
>   Unfortunately not every application will need to depend on GDA. Read
> more in the next section.
> 
> 5. The project's structure seems to be a bit blocking
> 
>   I think that services should be specified as GInterfaces that can be
> implemented by my own code, so I cannot run into a case when I want to
> subclass one of my classes to implement a service.
> 
>   Services might be provided as loadable plugins as well, so we end up
> with one base service and all other ones deriving from them. This makes
> it easy to let interfaces depend on other ones. This way we can depend
> on GDA optionally to provide the DataService and applications that build
> plugins can check for this module at compile time (enabling a small
> build for developers and good module splitting for distributors).
> 
> Regards,
>   Sven
> 
> [1] http://www.nongnu.org/criawips
> [2] http://cvs.gnome.org/viewcvs/gnome-office
> 
> PS: Does anyone here know projects that already use libgnomeoffice? I
> don't think there are any as Malcom was mentioning it for conglomerate,
> but configure.in doesn't mention it.

I've reorganised Conglomerate's plugin API to correspond closely to the
one used in libgnomeoffice, but we don't actually use it yet.  I plan to
do so once libgnomeoffice is readily available in the popular
distributions.

(Conglomerate doesn't _actually_ have plugins yet; they're still all
compiled into the main executable; they do go through a plugin-style
registration/discovery interface, though)

(Have been a bit busy with other stuff, alas)

Dave Malcolm