Raptor is a free software / Open Source C library that provides a set of parsers and serializers that generate Resource Description Framework (RDF) triples by parsing syntaxes or serialize the triples into a syntax. The supported parsing syntaxes are RDF/XML, N-Triples, Turtle, RSS tag soup including Atom 0.3, GRDDL for XHTML and XML. The serializing syntaxes are RDF/XML, N-Triples and RSS 1.0.
Raptor was designed to work closely with the Redland RDF library (RDF Parser Toolkit for Redland) but is entirely separate. It is a portable library that works across many POSIX systems (Unix, GNU/Linux, BSDs, OSX, cygwin, win32). Raptor has no memory leaks and is fast.
This is a mature and stable library. See the todo list for the current state information. A summary of the changes can be found in the NEWS file, detailed API changes in the release notes and file-by-file changes in the CVS ChangeLog.
Known bugs and issues are recorded in the to do list.
A Parser for the standard RDF/XML syntax as revised by the W3C RDF Core working group.
xml:lang, RDF datatyping and Collections.rdf:resource / resource attributesA parser for the N-Triples syntax as used by the W3C RDF Core working group for the RDF Test Cases.
A parser for the Turtle Terse RDF Triple Language syntax, designed as a useful subset of Notation 3.
A parser for the multiple XML RSS formats that use the elements such as channel, item, title, description in different ways. Attempts to turn the input into RSS 1.0 RDF triples. True RSS 1.0, as a full RDF vocabulary, is best parsed by the RDF/XML parser. It also generates triples for RSS enclosures.
This parser also handles the Atom 0.3 syndication format currently being standardised by the IETF Atom Publishing Format and Protocol working group.
A parser for Gleaning Resource Descriptions from Dialects of Languages (GRDDL) which allows reading XHTML and XML as RDF triples by using profiles in the document that declare XSLT transforms from the XHTML/XML content into RDF/XML which is the RDF content.
The parser does not support all the GRDDL styles, for example
dataview:namespaceTransformation, or perform recursive
transformations.
A serializer to the standard RDF/XML syntax as revised by the W3C RDF Core working group. This writes a plain triple-based RDF/XML serialization with no optimisation or pretty-printing.
A second serializer is provided using several of the RDF/XML abbreviations to provide a more compact readable format, at the cost of some pre-processing. This is suitable for small documents.
A serializer to the N-Triples syntax as used by the W3C RDF Core working group for the RDF Test Cases.
A serializer to the RDF Site Summary (RSS) 1.0 format.
The public API is described in the libraptor.3 UNIX manual page. It is demonstrated in the rapper utility program which shows how to call the parser and write the triples in a serialization. When Raptor is used inside Redland, the Redland documentation explains how to call the parser and contains several example programs. There are also further examples in the example directory of the distribution.
To install Raptor see the Installation document.
The packaged sources are available from http://librdf.org/dist/source/ (master site) and also from the SourceForge site. There are nightly snapshots of the development version which can also be browsed via CVSweb.
This library is free software / open source software released under the LGPL (GPL) or Apache 2.0 licenses. See LICENSE.html for full details.
The Redland mailing lists discusses the development and use of Raptor and Redland as well as future plans and announcement of releases.
Copyright 2000-2005 Dave Beckett, Institute for Learning and Research Technology, University of Bristol