Monday, November 5, 2012

W3C Linked Data Platform WG -- 1st Face to Face Meeting

I recently attended the 2012 W3C Technical Plenary / Advisory Committee (TPAC) in Lyon, France from October 29 to November 2.

RDF WG: Monday and Tuesday 
I attended the RDF F2F Working Group face to face meeting as an observer since I'm not an member of that WG though of course interested in a number of topics.  The RDF working group is nearing the end of its charter (Jan 2013) and making good progress on a number of its deliverables such as Turtle, JSON, TriG, n-triple, n-quad serialization formats.  There are a number of key issues that are of great interest such as ISSUE-77 marking rdf:Seq as archaic (this if particular interest to work at OSLC). There was a breakthrough in direction with named graphs by resolving to not define detailed semantics on identification of graphs, instead just allowing simply names/labels for graphs.
RDF WG Minutes: Day 1 and Day 2

TPAC Plenary Day: Wednesday
Jeff Jaffe CEO of W3C kicked off the day with a brief keynote and then logistics for breakout sessions.
I attended these sessions:
  • Social Web: lots of interest in linked data and social web.
  • Government Linked Data: discussion and update on work going on with existing WG, there is need for some guidelines and have need for LDP work
  • Linked Data for Web Developers: a fair amount of discussion around JSON, including a "white-boarding" session by Tim Berners-Lee talking about some approaches using JSON.  There was also discussion of a need for some schema-like need for RDF data, which I explained we have similar need and have some experience with OSLC Resource Shapes.
Linked Data Platform (LDP): Thursday and Friday 
Of course this was the primary reason I was here.  Agenda covered a range of topics as it was our first face to face meeting. Discussed Use Case and Requirements, Primer, Test Suite, Implementations, next F2F and of course spec issues.  Tim Berners-Lee attended both days and was very active in discussing the issues, he had strong views on how some of LDP should be shaped.
Probably the biggest change is the resolution around ISSUE-25 where the ldp:Container follows strong composition model instead of weaker aggregation.  There was discussion for a common set of needs around paging and ordering of contents.
LDP WG Minutes: Day 1 and Day 2

Overall Impressions
It is clear there are many W3C members that are very passionate and believers of Linked Data, including Tim Berners-Lee.  Discussions with many shown they are interested in keeping LDP simple and willing to jump in and add support to their products early.

Saturday, October 27, 2012

Trip Report from JavaOne 2012

Trip Report: JavaOne 2012 October 1-4, San Francisco 

I attended my first JavaOne conference, where I presented and attended a number of sessions and events.

Leveraging W3C Linked Data for Loosely Coupled Application Integrations

Tuesday Oct 2, 8:30
Track: Enterprise Service Architectures and the Cloud

There were about 90 people who preregistered for the session (see attachment) but seemed like there was a bit less than that at the actual session (50). Since they don’t serve the free coffee until after the 8:30 sessions, I felt like the attendees seemed very engaged by their responses and didn’t see anyone sleeping. The best was at the end where I had about 10 people approach me. Someone stated he was from a major news media company who asked how they could get involved in W3C Linked Data Platform (LDP) work and I highlighted some work at BBC that he might be interested in as well. Also a development manager from automative sector, asked how they could get involved as he was very interested in requirements traceability. Good news was that I could connect him with what other efforts in automative that were already occurring. There were a few others from healthcare and life sciences sector that said they were interested as well, handing out my card to a number of folks.

Linking the Java Application Lifecycle with Hudson

Wednesday Oct 3 4:30
Track: Development Tools

I was not on the original agenda to speak here but Mik Kersten CEO of Tasktop asked that I join him to explain Linked Data and OSLC, and give an overview of current activities. This session was also co-presented by Gregory Stachnick, Oracle Senior Director, Product Management. Greg is responsible for Oracle’s Eclipse-based tools strategy. Good overall flow considering some late changes, story around linking the lifecycle and need for standard integrations was good.

Some other activities:

Tuesday night Eclipse community meetup, good to talk with some Eclipse community members and talk about Lyo futures.
A number of sessions on JAX-RS, REST, WebSockets, Cloud, NoSQL, Hudson, CI, e4, ...
It was interesting to see the overall interest in REST, WebSockets, NoSQL and big data.

Overall very useful trip, look forward to trying to get back in 2013.

Friday, October 5, 2012

Quick Introduction to Linked Data and OSLC

I thought it would be useful to explain both Linked Data and OSLC using a simple buildup example.  Hoping to also show where Linked Data ends and OSLC picks up.  This was taken from a presentation that I did at Innovate 2012 and received better than bad feedback.

Monday, June 11, 2012

Innovate 2012: OSLC growing strong

This is my 4th IBM Rational conference where I've been a part of OSLC.  OSLC initiative was first announced at Rational Software Developer's Conference 2008 and after that I started working on OSLC specifications and implementations.  I co-presented then in 2009 with Mik Kersten of Tasktop Technologies, where we demonstrated OSLC in action.

Things have come a long way.  At Innovate 2011, there are a good number of OSLC sessions including a first even Jazz Interoperability Center powered by OSLC and other open specifications. I arrived early to help setup the renamed Integration Center which doubled in size from the previous year.  Thanks to the hard work of many, it was well organized and things went very smoothly.

I was able to meet with a number of customers who are very interested and excited about integrations using OSLC.  I was also able to attend a number of sessions where customers, partners and IBMers presented their findings, experiences and vision for integrations.  It was very rewarding to see so much OSLC content, there were about 40 sessions with OSLC content.

I ran a packed OSLC Workshop with Eclipse Lyo Project co-lead Michael Fiedler.  I get the feeling we'll be repurposing the workshop and running it many times over the year, perhaps even make it for a 3rd year in 2013?  I also co-presented with Angel Diaz, IBM VP Software Standards on "W3C Linked Data and OSLC".

It was also great to be part of the inaugural OSLC Steering Committee face to face meeting held in Orlando the day before Innovate kicked off.

There were many great conversations and events there in Orlando, the ability to put faces with names and have in person conversations is extremely valuable.  There is also a nice summary on OSLC website regarding OSLC activities at Innovate.

Thursday, May 10, 2012

W3C Launches Linked Data Platform (LDP) Working Group

Following on the W3C Submission Linked Data Basic Profile 1.0 and the Linked Enterprise Data Workshop around needs for standardization around Linked Data, the W3C has created the Linked Data Platform Working Group to look into this problem and produce a specification (W3C Recommendation) to address the stated items in the charter.

This is great news and follows on what we have been leveraging and learning when developing OSLC specifications built off of Linked Data as an architectural basis.  Many of the things you see in the charter and use cases the working group will face, have been a result of work by the OSLC community and community members such as IBM Rational.  By taking this effort to W3C this enables a broader set of applications and data to interoperate.  How does it do this?  By prescribing a single, simple, consistent way for applications to support Linked Data this means that more we can expect to see more and more compliant servers that are exposing their data.  This has a great quality that it makes it easier for client implementers being able to wring a client once and use across multiple server vendors -- this is a standard reason that we have done standards and continue to do standards.  There is much value in this alone, no doubt.  We gain additional value by building applications that pull data from a variety of servers and sources, leveraging the relationships (links) between the data and the meaning behind these links using standard and common vocabularies.  Reading the data is all good, though we need to a way to create and update the data.  We additionally need to a have a simple way to have these clients be able to create and update this data, it improves the quality of the data from the source and all benefit from a social and distributed set of clients/applications that operate over this data.

As the charter points out "The combination of RDF and RESTful APIs is therefore natural".  Why is this natural?  Since we operate on resources on the Web: get them, create them, update them, remove them, we need a way to identify these things, which URIs provide a nice mechanism for that, and access them over a network, which HTTP URIs provide a nice mechanism for that.  Since these resources on the Web are really not on the Web, for example a URI that produces a representations for a toaster isn't the toaster but a Web resource representing some information about it: it is a useful to have a model (RDF) for representing the state of these things.  Even though these concepts seem simple, there are many variations that exist on interpretation of existing specifications, best practices when multiple options exist and so on.  The Linked Data Platform WG looks to address a number of questions such as:

What is the current set of RDF datatypes that must be supported?
Currently it is left open to implementations to select a set, hopefully from a common and compatible set.
Which RDF formats must be supported?
RDF is a "resource description framework" and not a format, it has multiple formats that support it: RDF/XML, Turtle, N-3, JSON-LD, etc.  It would be nice for clients to be able to rely on a minimal subset of representations.
Which vocabulary terms are recommended?
When pulling together resource representations from separate servers, you gain value in analyzing these two resources by seeing which links they have in common and other interesting relationship.  Though, if both the resource representations used common, well-understood and standardized vocabulary terms to describe their data and links, then applications could correlate meaning from these common term usages without the need for extensive mappings applied.
What URL should be used to create new resources?  What should I receive back from that URL?
A common best practice is to enable new resource creation by POSTing a representation on a given say container URL.  A subsequent GET of that container URL would find that new resource any any previous resources that were created and still exist in that container.  This same model could apply to deleting the previously created resource, by issuing a DELETE on the resource URL it would both delete the resource and remove it from the container.
How can a client ensure it can create and update resources that have constraints applied by the server?
There are a number of existing applications and cases for future applications, where constraints may need to be made on the validity of the resource representation prior to the server creating a resource or allowing a new updated revision to be created.  It would helpful to have a representation of these constraints that a client could easily fetch and apply to its representation prior to submitting it to a server.
These are just a sample of the issues that the charter highlights and the working group looks to tackle.  The member submission for a Linked Data Basic Profile address a subset of these issues and a future derivative or version will likely be introduced to handle these cases.  Though in the spirit of making progress and getting value out of something in the near future, it would seem logical that the working group would focus on a subset in its version 1.0 specification.

The working group charter outlines a timetable that is an initial guess on when a final "Recommendation" is available, which is looking like early 2014 with a first draft for review later in 2012.  I highly encourage  everyone to get involved: providing use cases and requirements, reviewing material, providing implementation feedback, writing specification...the more review and collaboration we have on the better changes for success we'll have.  This has proven true in OSLC and W3C.

Monday, April 2, 2012

Linked Data Basic Profile - W3C Member Submission

A W3C member submission titled "Linked Data Basic Profile" has been published at  This submission highlights some of the key best practices and patterns that have helped leverage Linked Data as an approach to integrating lifecycle tools and applications.  This submission contains a proposed specification, use cases and requirements, and a simple RDF schema document describing the vocabulary.  The outcome of a W3C Workshop in December 2011 on "Linked Enterprise Data Patterns" explored various topics around the usage of Linked Data approach for read-write application integration use cases and concluded with the workshop attendees recommending the formation of a W3C workgroup to develop and endorce a specification around the need for a minimal foundation to build Linked Data application from.  Be on the look out to participate in the evolution of this at W3C and the adoption of it within OSLC.  This submission represents a significant step in the adoption of Linked Data as an integration architecture and thank those who helped contribute.

Wednesday, January 25, 2012

Reconsidering the "S" in OSLC (as it is not the same "S" in SOA)

 technically stands for "Services" in OSLC but what are these "Services"? In doing a little digging, the original intent of the name was to focus on REST and therefore the word "services" was introduced to represent "REST services". This has led to a number of problems with confusion over what type and kind of services are we talking about. For instance, there is a natural tendency to map the OSLC use of the word service with that of SOA (Service Oriented Architecture), which is not at all the association we want. Will this be a constant problem as OSLC expands into new domains and 3rd party adoption?  I believe so.

There are a couple of things to focus on, is what we really want to achieve with OSLC and what name awareness we want. So that means, continue to focus on "OSLC" as a term and not worry too much about what each letter means without context.

I'm proposing to fix the problem with "S" standing for "Services" and instead introduce "Specifications". So try this on for size,

    Open Specifications for Lifecycle Collaboration (OSLC)

I'd be interested in any reaction to this change, support or problems. I believe this is a necessary change and the right one. It captures what OSLC is really about. Yes, changing this provides a bit of short term pain but the longer we wait it will be harder to change and we'll have to continue to deal with the confusion it introduces.

Of course there are a number of logistics to consider with such a change:
  • Fixing names used on websites, articles, charts, etc (like the title of this Community)
  • Considering updating more complicated things like OSLC intro videos
  • Considering a better domain name
I did blog last year on The "O" in OSLC, which is still valid as "open" by the way.

Do you see this as being an issue worth addressing?
Do you have other suggestions for the letter "S"?

Be interested in hearing both support for this, as well as any concerns.