ANNOUNCE: Rx4RDF and Rhizome 0.3.0

Rx4RDF is application stack for building RDF-based applications and web
sites.
Rhizome is a Wiki-like content management and delivery system built on
Rx4RDF that generalizes the wiki concept in several ways.

What's new?

This release is focused on making Rhizome usable for running small-scale
web sites:

* Much improved documentation, including manuals for Rhizome, Raccoon
and ZML.

* Many features added to Rhizome -- it now has (nearly) all the
functionality
you'd expect in a full-featured Wiki. It also much easier to browse and edit
the underlying RDF model (and the default template is less ugly).

* Raccoon's security has been enhanced by disabling potentially dangerous
settings by default and by the creation of an audit log of changes to the
database. Rhizome now supports fine-grained authorization of the changes
to the RDF model and provides a secure default authorization schema.

In addition, there have several other enhancements, see
http://rx4rdf.liminalzone.org/changelog.txt for more details.

(In terms of RDF state of the art I think the most interesting thing in 
this release is its approach to the authorization of changes to the 
model. Basically triples are too low level to use for intuitive 
authorization rules in most problem domains -- generally you'll want 
create rules at an object level that will apply to a subgraph of 
resources, for example, access control to a page will extend to a 
collection of resources that make up the page.
To achieve this the user can partition the model by declaring properties 
as subproperties of a "authorizes" predicate. Then for any changed 
statement, the authorization routine can find relevant authorizing 
resources by transitively following those predicates. I suspect this 
pattern can be applied to other common problems, for example, for an 
intelligent merge of models.)

More Info:

* Rx4RDF is a set of technologies designed to make RDF more accessible
and easier to use. It includes:

** RxPath provides a deterministic mapping between the RDF abstract
syntax to the XPath data model,  allowing you to query, transform and
update a RDF model with languages syntactically indentical to XPath,
XSLT and XUpdate (dubbed RxPath, RxSLT, and RxUpdate respectively).

** ZML  is a Wiki-like text formatting language that lets you write
arbitrary XML or HTML (using Python-esque indentation rules), enabling
you to author XML documents with (nearly) the same ease as a Wiki entry.

** RxML is an alternative XML serialization for RDF that is designed for
easy authoring in ZML, allowing novices to author and edit RDF metadata.

* Raccoon  is a simple application server that uses an RDF model for its
data store, roughly analogous to RDF as Apache Cocoon is to XML. Raccoon
uses RxPath to translate arbitrary requests (currently HTTP, XML-RPC and
command line arguments) to RDF resources, each of which can be
associated with RxSLT and RxUpdate stylesheets.

* Rhizome is a Wiki-like content management and delivery system built on
Raccoon that takes the concept of the Wiki to the next level: everything
is editable, not just content but its meta-data and behavior, even the
structure of the site itself. Furthermore, wiki entries are abstract
globally unique RDF resources that can have any kind of content and
whose presentation is contextual.

Homepage:
http://rx4rdf.liminalzone.org/

Download:
http://sourceforge.net/project/showfiles.php?group_id=85676

-- adam (asouzis @ user.sf.net)

Received on Friday, 14 May 2004 07:49:25 UTC