Hi Sebastian. Thank you! We had been looking forward to that and will
gladly dig through it.
Alessandro
On 7/22/11 3:06 PM, Sebastian Schaffert wrote:
Dear all,
following up the discussion in the community workshop in Paris, I would like to
formally offer the integration of our Linked Media Framework into Apache
Stanbol. The software is currently available under BSD license at the Google
Code website at http://code.google.com/p/kiwi/. Here is a short summary of the
functionality it can offer (mostly from the website where you can also find
more in-detail documentation):
--- 8< ---- 8< ---
The Linked Media Framework is an easy-to-setup server application that bundles
central Semantic Web technologies to offer advanced services. The Linked Media
Framework consists of LMF Core and LMF Modules.
LMF Core
========
The core component of the Linked Media Framework is a Linked Data Server that
allows to expose data following the Linked Data Principles:
* Use URIs as names for things.
* Use HTTP URIs, so that people can look up those names.
* When someone looks up a URI, provide useful information, using the standards
(RDF, SPARQL).
* Include links to other URIs, so that they can discover more things.
The Linked Data Server implemented as part of the LMF goes beyond the Linked
Data principles by extending them with Linked Data Updates and by integrating
management of metadata and content and making both accessible in a uniform way.
In addition to the Linked Data Server, the LMF Core also offers a SPARQL
endpoint.
LMF Modules
===========
As extension for the LMF Core, we are working on a number of optional modules
that can be used to extend the functionality of the Linked Media Server:
Implemented:
* LMF Semantic Search offers a highly configurable Semantic Search service
based on Apache SOLR. Several semantic search indexes can be configured in the
same LMF instance using an RDF Path Language that allows traversal over several
Linked Data sources.
* LMF Linked Data Cache implements a cache to the Linked Data Cloud that is
transparently used when querying the content of the LMF using either SPARQL or
the Semantic Search component. In case a local resource links to a remote
resource in the Linked Data Cloud and this relationship is queried, the remote
resource will be retrieved in the background and cached locally.
* LMF Reasoner implements a rule-based reasoner that allows to process
Datalog-style rules over RDF triples; the LMF Reasoner is based on the
reasoning component developed in the KiWi project, the predecessor of the LMF
Under Progress:
* LMF Permissions implements and extends the WebID and WebACL specifications
for standards-conforming authentication and access control in the Linked Media
Framework. (state: almost completed)
* LMF Enhancer offers semantic enhancement of content by analysing textual and
media content; the LMF Enhancer will build upon the Apache Stanbol framework
(state: started)
* LMF Media Interlinking will implement support for multimedia interlinking
based on the work in the W3C Multimedia Fragments WG and theW3C Multimedia
Annotations WG
* LMF Versioning implements versioning of metadata updates; versioning itself
is already carried out by LMF Core, but the management of versions will be
carried out by this module (state: started)
--- 8< ---- 8< ---
As far as I can see, Apache Stanbol and the Linked Media Framework currently
cover mostly complementary areas and I think that a combination could be of
benefit for both projects. In particular, I would think that the Linked Media
Framework can also offer an almost ready implementation of the Stanbol Content
Hub, as well as a free reasoner and full Linked Data capabilities (server as
well as client) and Semantic Search.
Last but not least it is also of strategic interest for the KMT group at
Salzburg Research to (1) integrate the technologies developed in the group, and
(2) avoid duplication of effort if it is not necessary.
What I can offer is that - following a discussion on the mailinglist - we
donate the LMF code base to Apache Stanbol and try integrating the two projects
in the next months. Since the LMF is easily deployable as a .war file, a first
step could be to deploy the web application inside Apache Stanbol as an OSGi
web application. This could demonstrate the usefulness of the combination. Of
course, in the course of the integration it would be necessary to isolate the
individual modules of the LMF as separate components.
Difficulties I see at the moment (just to mention these...):
- technological issue: LMF is currently not using OSGi, but it uses a Gradle build system, Java 6
EE dependency injection (CDI) and a typical Java EE architecture which is incompatible with OSGi
for now; one of our selling points is also "easy setup" and "lightweight", so I
would not really like to change this for a complicated architecture ...
- license issue: LMF might still use libraries that are released under
incompatible licenses, so this needs to be checked. In particular, Hibernate is
still licensed under LGPL, and it is one of the core libraries of the LMF;
porting to other persistence frameworks might require a lot of effort
- organisational issue: LMF is developed in several projects that have their
specific goals; we will in some way need to still be able to follow our goals
in these projects, e.g. by appropriate Stanbol extensions; all software
developed in these projects is Open Source though...
Now let the discussion begin ... ;-)
Sebastian
--
M.Sc. Alessandro Adamou
Alma Mater Studiorum - Università di Bologna
Department of Computer Science
Mura Anteo Zamboni 7, Bologna - Italy
Semantic Technology Laboratory (STLab)
Institute for Cognitive Science and Technology (ISTC)
National Research Council (CNR)
Via Nomentana 56, 00161 Rome - Italy
"As for the charges against me, I am unconcerned. I am beyond their timid, lying
morality, and so I am beyond caring."
(Col. Walter E. Kurtz)
