rdf-ext

RDF Interfaces Extension

Attention: a lot of work has gone through rdf-ext 0.3.0 and it doesn't match this documentation. Right now you can have a look at the tests and at the different packages under the rdf-ext organization. Documentation will be updated soon

RDF-Ext provides a JavaScript library for working with RDF & Linked Data.

Parsing

• Abstract
• JSON-LD
• Turtle
• N-Triples
• DOM/RDFa
• RDF/XML
• Microdata

Serializing

• Abstract
• JSON-LD
• Turtle
• Microdata

Stores

For persistence, RDF-Ext provides several store implementations.

• Abstract - Abstract implementation, can be used to build your own store
• LDP - Query an external Linked Data Platform via RESTful HTTP requests
• File system - Using the file system
• In Memory - Store loaded in memomory
• Single graph (memory) - Store has only a single graph
• SPARQL - Uses the Graph Store HTTP Protocol interface
• RDFStore wrapper - Store built on top of Rdfstore-js
• Multistore - Use multiple store depending on the IRI
• Local/Remote - Uses a local store or a remote store depending on the IRI
• ACL wrapper - Add ACL support to your RDF store

Design

RDF-Ext is an extension of the RDF Interfaces specification. The RDF Interfaces specification defines interfaces for graphs, triples, nodes and parsers/serializers. However, the spec does not define an interface to access triplestores using NamedGraph IRIs. RDF-Ext fills this gap by providing a definition of a Store-Interface with an asynchronous API.

The motivation for an asynchronous API is simple: A JSON-LD context for example can be defined as an URL. The parsing and serialization process must therefore be asynchronous. The RDF-Ext spec contains an extended interface for parsers and serializers to work asynchronously.

With ECMAScript 6 (ES6) JavaScript introduces some new features. RDF-Ext uses the new Promise feature to handle asynchronous function calls easier.

Requirements

RDF-Ext requires a library, which implements the W3C RDF Interfaces API. Here is a list of known working implementations:

• reference implementation
• rdf
• rdfstore-js

Usage

In general, consult the documentation for the RDF Interfaces and RDF-Ext specifications for details about how to interact with the library.

node.js

RDF-Ext is available on npm, to install it run:

npm install rdf-ext

In the code, import RDF-Ext:

var rdf = require('rdf-ext');

Browser

Just import RDF-Ext:

<script src="/js/rdf-ext.js"></script>

If you want to use rdfstore-js it must be imported first. Because rdfstore-js comes with an outdated version of JSON-LD it must be deleted afterwards:

<script src="/js/rdfstore.js"></script>
<script>delete jsonld;</script>

Support

Issues & feature requests should be reported on Github.

Pull requests are very welcome.