[XESAM] Extension proposal, alternative search services

[Evgeny Egorochkin]

On Friday 08 June 2007 09:05:19 you wrote:
> > I just wanna toss this idea out in the wild.
> >
> > I want to make it easy to have multiple services expose a xesam search
> > interface. We would still have the standard desktop search engine with
> > the dbus path and name as specified, but other implementations of the
> > search interface could be useful too. Consider fx if Gnome's Mugshot
> > applet ( http://mugshot.org) exposed a xesam search service that could
> > search in mugshot groups, feeds, and persons. This would not be suitable
> > as an integrated part of the main desktop search service. Another example
> > could be a xesam wrapper for the Yahoo REST api.
> >
> > This way we could (at some point in the future) have a small "swarm" of
> > xesam search services (likely with the desktop one as the most
> > prominent), and applications like deskbar could aggregate these in a a
> > nice
> > search-everything-you-can-dream-of-and-then-some applications.
> >
> > We can achieve this with almost no changes to the current search
> > proposal. What we basically need is some way to introspect what
> > ontologies the search engine is capable of using, and we probably need
> > that anyway.
> >
> > What I actually propose is this: Add a session property
> > vendor.ontologiesthat has value type aas, an array of ontology
> > definitions which are triplets [unique_name,version,path]. So fx hooking
> > up to the Yahoo service and calling GetProperty(session, "
> > vendor.ontologies") returns [["yahoo", "1.0",
> > "/usr/share/ontologies/yahoo-1.0"]].
> >
> > If the main xesam desktop search service had a 3rd party onto installed
> > it might return [["xesam", " 1.0", "/usr/share/ontologies/xesam-1.0],
> > ["my-app", "0.3.4", "/usr/share/ontologies/my-app-0.3.4]].
>
> I was quite in a rush  last night so I forgot half the message of course...
>
> The values of the ontology-triples [unique_name, version, path] deserve
> description:
>  - unique_name: This is a name that uniquely describes the vendor of the
> ontology.
>  - version: the version of the ontology
>  - path: the absolute path to the ontology
>
> This leads me with a need to define how ontologies are installed.  I would
> suggest that an ontology is a directory under
> {XDG_USER_DATA_DIR,XDG_SYSTEM_DATA_DIR}/ontologies named
> <unique_name>-<version>. All files (in a yet to be specified format) in
> here are treated as part of the ontology except one designated file (in a
> yet to be specified format) which contain metadata about the ontology. This
> metadata could fx be:
>  - Vendor name (the unique name as in the dir-name)
>  - Ontology version
>  - Full vendor name (free form string)
>  - Ontology description
>
> Anyways, any thoughts? Cheers,

For RDF(S) you don't really need this file. You can embed this info anywhere. 

The problem I see here is I'm not sure this is the only change necessary to 
let several xesam indexers work in parallel... I'm no DBUS expert and 
actually hardly know anything, but can several programs run a service with 
the same name?

Also, consider that indexers will likely have plug-ins which extend their 
ontologies, so ontology version may not be as informative, or at least it 
should be clarified that you are describing only the core part of the 
ontology.

Another point: many ontologies can co-exist with the aid of namespacing. You 
can lump together results from queries to any number of indexers, and it'll 
work just fine.

-- Evgeny