OpenNebula

Hi,
I've found an issue that is related to both ONE and the OCCI specification. Currently ONE uses XML as
OCCI representation format. Meanwhile OCCI seems to go onto another direction: defines only HTTP header
and X/HTML formats.

I've already started a discussion on the OCCI mailing list regarding this topic, eg. to clarify OCCI's
directions in this regard. See: http://www.ogf.org/pipermail/occi-wg/2010-May/001805.html

Thijs Metsch wrote: "Right now Andy (Edmonds) and Gary (Mazzaferro) are working on this topic. Especially
with an eye on RDFa and XHTML5." (http://www.ogf.org/pipermail/occi-wg/2010-May/001806.html)

Sam Johnston wrote: "For the XML rendering, in order to support both user (browser) and machine (software)
clients we decided to go with XHTML which we'll focus on once we've digested the public feedback and filled
in the gaps in the existing specification." (http://www.ogf.org/pipermail/occi-wg/2010-May/001809.html)

As a future ONE/OCCI user, I have great concerns with the above approach. Backed by some designer,
developer background, I have great fears that neither X/HTML nor RDFa would really support machine clients
that matter eg. clients having the role to control the cloud (remote CLI clients, batch agents, system
integration...) What's more I even don't think that an X/HTML interface would support web applications'
needs (eg. would it be good as a business logic layer?).

Since the topic is related mainly to the ONE platform (and not our planned extensions) I decided not to
keep up the discussion on my own, but kindly ask you to help. If you also have concerns with the above
approach, would you be so kind as to contact OCCI and discuss the issue:) Maybe it is not too late, since
Sam Johnston also put: "It's not too late for you to provide input so if you have any feedback then it
would be gratefully received."

Kind regards,
Gyula

Bottom line: I've got no working experience with RDFa, just "googled" the topic and looked thru some
intros. Well, since RDFa is a relatively young spec, less then 2 year old, noone could have much
working experience:)). Meanwhile the authors' original intention and the current user base might be
relevant:

• "We introduce RDFa, which provides a set of XHTML attributes to augment visual data with machine-readable
  hints." (http://www.w3.org/TR/xhtml-rdfa-primer/)
• Some names of the current user base: Facebook, Google (http://rdfa.info/wiki/RDFa_Wiki)

To my understanding RDFa is an annotation language, that is used to embed structured data within the user
interface (eg. X/HTML) and is useful for search engines and the like in order to index pages, and to provide
structured and more usable query interfaces. I do not see how cloud management agents would fit this picture.