Re: Support for more ontology foo in beagle xesam adaptor

["Mikkel Kamstrup Erlandsen" <mikkel kamstrup gmail com>]

On 17/12/2007, Debajyoti Bera <dbera web gmail com> wrote:
> > Small question, why are there two different page-count fields?
> > Couldn't they just be one like it is done in tracker. And what about
> > pdf's, does beagle support extracting the page-count from that?
>
> Noticing the ongoing effort to add more ontology to the beagle-xesam adapter,
> I think I should mention one shortcoming (or feature, depending on how it
> looks like):
> Beagle was designed to be a desktop search infrastructure which can index any
> kind of data you want it to index. The "backends" and "filters", which are
> responsible for actually generating the indexed data, are free to put the
> data in any format they like. We never had any restriction on the names of
> the fields that they use. We mildly _suggested_ that they use commonly used
> names (either looking at similar Filter or Backend or by following Dublin
> Core metadata names) so that the UIs can also display results from that
> source. But it was never a requirement.
>
> Developing the right namespace and name of the field for a particular property
> of a some kind of data is not an easy task. Also such a list was available an
> year or two ago, when most of the Filters and Backends were written. Thus it
> made sense to give the freedom to Filter and Backend authors. Note that
> nothing stops from anyone running Beagle to create a Backend or a Filter out
> of the Beagle tree and dropping it in the right place for Beagle to pick it
> up as a plugin. Probably the usual beagle UIs would not be able to display
> results from the new source, but thats the authors responsibility
> (BeagleClient API exists if he wants to create a special purpose UI for his
> specialized data).
>
> What the above caused was a hotchpotch of property names and abundunt use of
> the namespace "fixme". I would not be surprised to find names
> like "dc:author", "fixme:author" or "fixme:tags" and "fixme:tag". Its stupid
> but it is a daunting task to decide a policy and make the changes
> everywhere :(
>
> Frankly I am without clues how to resolve this. That, given the fact that life
> has been going well even with this mess, at least till now ;-).
>

Hi, (I am one of the xesam guys in case you wonder why I drop in)

I think there are three ways to solve this:

1) The current approach of beagle-xesam; create a mapper from the
xesam ontology <-> Beagle "ontology".

2) Adapt Beagle to use the xesam onto throughout - note that this
would still not ban people from making up their own fields.

3) Decide not to use the xesam onto, but create another one for
beagle, then use 1).

Being a Xesam guy, 2) is obviously my long term preference. However I
think the current approach (1) is a very good start. It allows to use
the xesam ontology without index changes.

As far as my Beagle knowledge goes it will not be easy change
everything to the xesam onto as the field names are hard coded in many
places. So a temporary solution is probably good...

Cheers,
Mikkel