cmis message
Subject: joining the TC, introduction, HTTP thoughts
From: Julian Reschke <julian.reschke@greenbytes.de>
To: cmis@lists.oasis-open.org
Date: Fri, 05 Dec 2008 15:39:17 +0100
so I finally joined OASIS and the CMIS TC -- sorry for the delay.
For those who do not know me already: I'm working for greenbytes, a
small consulting and development shop. In the past, we've been
concentrating mainly on JAVA based content management systems and the
associated APIs and wire protocols.
In particular, I've been a contributor to the IETF WebDAV working group
since around 2001, and have participated in the development of almost
all WebDAV specifications that came out after (DeltaV, ACL, property
types, redirects, search, ...).
The work on WebDAV also caused me to become interested in doing work on
HTTP -- there are many areas where RFC 2616 isn't as clear as it should
be with respect to *authoring* of WebDAV resources. It took some time,
but in the end the IETF decided to charter a new HTTP Working Group
(HTTPbis) in December 2007. We are now working on a revision of RFC2616,
and I'm one out of three editors. (see <http://tools.ietf.org/wg/httpbis/>).
I have also been a member of the JCR Expert Group (JSR-283) since May
2006, and implemented the spec for one customer, leveraging the Apache
Jackrabbit SPI interfaces and the "JCR2SPI" implementation (for which
I'm committer as well).
The first thing I'd like to work on is improving the CMIS text that
talks about the relation to WebDAV. In its current state it is (IMHO) in
the wrong place (I think the comparison should be made with the HTTP
binding, not the model), and lacks some precision.
In general, although JCR is an API, and WebDAV a wire protocol, both
*do* define a model as well. Sooner or later, people will want to map
between CMIS and those, so I think it's inevitable that mappings will be
defined -- this could be here, in a JSR, in an open-source project like
Jackrabbit, or the IETF. I don't think the place matters a lot, as long
as it's done properly.
It's some time ago that I read the CMIS base spec, but my first
impression was that CMIS is a proper subset of the functionality defined
in JCR (maybe except query), and defining a mapping CMIS->JCR should be
simple. The other way around however will be harder. It seems to me that
it would be good to minimize differences where possible.
Similarly, WebDAV has *large* overlap with CMIS, some stuff CMIS doesn't
need (like locking), and some stuff missing (type model). On the other
hand, WebDAV is extensible, and WebDAV extensions for remoting JCR will
be developed anyway.
Furthermore, there's some overlap with current discussions on the Atom
Protocol mailing list, such as defining extensions for hierarchical
collections. It would be cool if we could avoid inventing this for CMIS,
if it's already done somewhere else. In this context it would be great
to have somebody with GData (Google Data) knowledge in the TC. Also, I
expect that Microsoft's AtomPub experts should be involved as well (or
are they here already?).
Finally, I'd like to understand whether CMIS is mainly thought as a way
to connect document stores, or whether we expect it to be used for
client (desktop) integration as well. In the latter case it would be
good to understand why we're doing something new, instead of extending
WebDAV which already has broad client support.
Best regards, Julian
Re: [cmis] joining the TC, introduction, HTTP thoughts
From: Al Brown <albertcbrown@us.ibm.com>
From: "David Nuescheler" <david@day.com>