Soprano 2.0 released

The Soprano development team is proud to announce the release of Soprano 2.0, the completely revamped stable version of the powerful desktop RDF framework.

The Soprano project was born from the QRDF prototype by Daniele Galdi and Duncan Mac-Vicar when the need for a proper RDF[1] storage solution for the KDE implementation of Nepomuk[2] technologies arose. In the Nepomuk project, all data is stored as RDF quadruples, and as such Soprano is one of the core elements for Nepomuk in KDE. Today Soprano is developed within the KDE source code repository as a direct dependency of the KDE Nepomuk[3] components.

Soprano is a pluggable open-source RDF storage, parsing, and serialization framework based on QT4[4]. Soprano is targeted at desktop applications that need an RDF solution for (meta)data storage. From the beginning its API has been optimized for easy usage and simplicity.

Soprano has a wide range of features, the most important ones include:

  • Storage backends for Redland[5] and Sesame2[6]
  • RDF parser and serialization plugins for Raptor (rdf+xml, Trig, Turtle) and NQuads
  • An iterator-based design for query result iteration and triple/quadruple listing
  • Hierarchical model (graph) design allowing to stack different filters on top of an RDF repository
  • Full support for contexts (aka named graphs or RDF quadruples)
  • A rule-based forward inference engine
  • A full-text index based on CLucene[7] which allows fast queries on literal statements
  • A server and client library including a simple daemon implementation
  • A powerful command line tool to control a Soprano server or directly modify and query a Soprano repository

The Soprano source code package can be retrieved from