[Xesam] Meaning of xesam:url

[Mikkel Kamstrup Erlandsen]

2008/8/3 Michael Albinus <michael.albinus at gmx.de>:
> Hi,
>
> I'm currently playing with different search engine. It looks to me like
> all of them have an own idea of xesam:url, which makes it a little bit
> hard to interpret in a client.
>
> - The XesamOntology95 says as data type "list of URLs". This seems to be
>  an error, all engines return just a string.

Yes, this should just be a string. Luckily no-one used it like this :-)

> - When it is a local file, beagle returns a "file:///a/b" URL. Contrary,
>  strigi returns a local file name like "/a/b". I guess, it shall always
>  be a URL.

Right.

> - The engines use xesam:url for providing further information. Examples:
>
>  * "file:///.../Mail/Local Folders/Inbox/?id=240915" means file "Inbox",
>    char position 240915 (beagle)
>
>  * "/home/albinus/Mail/default/21/ChangeLog" means (email in) file
>    "21", attachment "ChangeLog" (strigi)
>
>  * ".../gnome-keyring_2.20.orig.tar.gz/gnome-keyring-2.20/po/ChangeLog"
>    means a file in a zipped tar (strigi)
>
>  I believe, such information shall be given in other xesam fields.

Well, that's hard to decide. Requests for standardizing the contents
of xesam:url has been aired a few times, but I think it is really hard
to achieve. For example Evolution and KMail handles email uris very
differently, same applies for all manner of similar apps between KDE
and Gnome. It would almost be a whole spec in itself to do full
standadization of this.

I think you can only trust it when you have good reason to do so. Fx
for files, web pages, and the likes. If you have apriori knowledge of
your platform you can use them as well. For instance Gnome's deskbar
can open the emails in Evolution.

I wish we could do better, but I don't have many ideas. Anyone with a
fresh mind please chime in.

Cheers,
Mikkel