W3C | Submissions

Team Comment on the "Linked Data Basic Profile 1.0" Submission

This Submission provides a Use Cases and Requirements document which motivates development of a Linked Data web environment managable and manipulatable with accepted HTTP REST architecture. The accompanying Linked Data Basic Profile defines such an environment by defining specific REST interfaces for Linked Data resources. This environment complements the popular RDF stack provided by RDF/XML, Turtle and SPARQL to build an infrastructure suitable for enterprise environments, leveraging RDF's ability to provide loose coupling of applications. The principle contribution of this Submission is the definition of a Basic Profile Resource (BPR) and a Basic Profile Container (BPC), drawing a practical distinction between Resources, representing entities in the world like people, cars or software bugs, and Containers, which provide access to groups of resources.

The definitions of BPR and BPC offer profiles which select from the flourishing family of RDF representations by requiring RDF/XML and encouraging Turtle. They promotes an architecture which links well with WEBARCH, e.g. exploiting the usual HTTP verbs as well as management concepts such as Etags.

The Submission picks a practical but potentially controversial approach to minimal metadata by defining some processor-added properties (dcterms:modified, dcterms:creator). Other than that, the Submission preserves RDF's anybody-can-say-anything-about-anything semantics, advising a BPR's types and predicates are unconstrained, even requiring clients to preserve unknown assertions when updating BPRs.

Probably the most novel contribution is the Basic Profile Container (BPC), which specifies a protocol around the relatively common design pattern of lists of REST resources. Similarly to the way AtomPub exposes POST interfaces to add e.g. blog pages to a blog, BPC defines a convention for adding RDF resources to lists of such resources. These lists can be fetched by a client, manipulated, and even be traversed in discrete chunks by paging information embedded in the RDF about the container.

Future Work

As noted above, this document provides a Linked Data groundwork. This leaves some work items for the community or a future Working Group, such as the proposed Linked Data Platform Working Group:

  1. The document specifies that "No minimal set of patch document formats is mandated by this document." Of course for interoperability, the world will need concrete patch proposals, e.g. TurtlePatch.
  2. Evaluation of the selection of the langagues for the profile; the profile requires RDF/XML and encourages Turtle, but much of the REST world is focused on JSON. JSON-LD or some other JSON representation may reach a wider audience than RDF/XML or Turtle.

Continuing discussion of this topic is welcome on the mailing list public-ldp@w3.org (achives).

Eric Prud'hommeaux <eric@w3.org>