RDFauthor

is an editing solution for distributed and syndicated structured content on the World Wide Web.

The system is able to extract structured information from RDFa-enhanced websites and to create an edit form based on this data. To this end, we make use of semantics-aware editing widgets that hide most of the RDF data model from the user, thus allowing more people to author semantic content. If the embedded data does not suffice to create a rich user-supporting editing view, the underlying Semantic Web infrastructure is used to retrieve additional schema-related information about the elements used.

RDFauthor Google Code project page

RDFauthor API Documentation

Overview

The idea of RDFauthor is to make arbitrary RDFa-annotated web pages editable. By extending RDFa with named graphs, it is even possible to edit information originating from different sources within the same form.

The basic cycle of how the RDFauthor approach works is depicted on the right. It consists of the following processes:

• Page creation and delivery (a): An HTML page is created based on data from e.g. an RDF store. Triples are embedded using RDFa with named graphs extension. Additionally, for each writable graph, a SPARQL/Update endpoint is defined.
• Client-side page processing (b): Embedded triples are extracted and placed into rdfQuery databanks, one for each named graph.
• Form creation (c): Based on the triples extracted, an edit form is created. It contains widgets for all the triples based on rdf:type, property, datatype etc.
• Update propagation (d): Changes are sent back to the sources via SPARQL/Update for each named graph separately. Access control rules can therefore be ovserved on the graph level.

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Provenance

In order to be able to use RDFauthor, a few requirements must be met. All triples that are to be editable must beembedded in the page by means of RDFa. If triples for the page originate from different sources, they have to be placed in different named graphs. We use the named graphs extension proposed by Toby Inkster. Additionally. the page must contain provenance information for each named graph as RDFa triples. To this end, we provide an update vocabulary. It allows to define for each named graph an update endpoint and optionally a query endpoint. The update endpoint is assumed by RDFauthor to understand SPARQL/Update queries. RDFauthor uses a subset of SPARQL/Update (INSERT DATA syntax) where each triple to be inserted is explicitely given. It is sufficient to support only this subset.

Examples

As of version 0.9, the OntoWiki Project uses RDFauthor as its primary editing system. To make use of RDFauthor, OntoWiki had to be extended in two ways:

• all resource templates have been upated to include RDFa and provenance information,
• a SPARQL/Update enpoint was added.

Additional examples will be added subsequently.

Contact

Norman Heino Johannisgasse 26, Zimmer 5-08 04103 Leipzig Tel.:   +49 341 97 32368 E-Mail, Research Group, Workpage

Sebastian Tramp (geb. Dietzold) Johannisgasse 26, Zimmer 5-08 04103 Leipzig Tel.:   +49 341 97-32366 E-Mail, Workpage, Research Group, WebID