RDF.dart: A Dart Library for Working with RDF

RDF.dart is a Dart library designed to make it easy to work with RDF (Resource Description Framework) data structures and concepts. It provides core data structures for representing RDF triples, graphs, datasets, and literals, along with utilities for managing datatypes and IRIs.

Features

• Core RDF 1.2 Data Structures:
  • IRI: Represents an Internationalized Resource Identifier string.
  • IRITerm: Represents an IRI used as an RDF term (subject, predicate, object, or graph name).
  • Literal: Represents an RDF literal with datatype and optional language tag.
  • BlankNode: Represents an RDF blank node.
  • TripleTerm: Represents an RDF triple used as an RDF term (subject or object) as defined in RDF 1.2.
  • RdfTerm: The abstract base class for all RDF terms (IRITerm, BlankNode, Literal, TripleTerm).
  • Triple: Represents an RDF triple (subject, predicate, object - where object can be any RdfTerm, including a TripleTerm).
  • Graph: Represents a collection of RDF triples.
  • Dataset: Represents a collection consisting of one default graph and zero or more named graphs.
• Datatype Handling:
  • Built-in support and validation for common XSD datatypes (e.g., xsd:string, xsd:integer, xsd:double, xsd:dateTime, xsd:boolean, xsd:date, xsd:duration, and more). See XSD class.
  • Support for rdf:langString.
  • (Planned) DatatypeRegistry for managing custom datatypes.
• IRI Validation & Parsing:
  • Robust IRI parsing based on RFC 3987.
  • Validation checks for IRIs.
  • Access to IRI components (scheme, authority, path, query, fragment).
• Immutability: Core data structures (IRITerm, BlankNode, Literal, TripleTerm, Triple, IRI) are immutable.
• Well-Tested: Core features have comprehensive unit tests.

Getting Started

1. Add the Dependency: Open your pubspec.yaml file and add rdf_dart to your dependencies:

   dependencies:
     rdf_dart: ^1.0.0 # Replace with the latest version

2. Install the Package: Run this command in your terminal:

   dart pub get

3. Import the Library: In your Dart code, import the rdf_dart library:

   import 'package:rdf_dart/rdf_dart.dart';

Usage

Here's a simple example demonstrating how to create RDF objects:

import 'package:rdf_dart/rdf_dart.dart';

void main() {
  // Create some IRIs
  final subject = IRITerm(IRI('http://example.org/subject'));
  final predicate = IRITerm(IRI('http://example.org/predicate'));
  final object = IRITerm(IRI('http://example.org/object'));

  // Create a string literal
  final stringLiteral = Literal('Hello, world!', XSD.string);
  print(stringLiteral); // Output: "Hello, world!"

  // Create a triple
  final triple = Triple(subject, predicate, object);

  // Create a Dataset
  final dataset = Dataset();

  // Add the Triple to the Dataset
  dataset.defaultGraph.add(triple);
}