alcamo/rdf-literal-workbench

RDF literal creation and validation

0.1.1 2026-07-09 08:26 UTC

Requires

• php: 7.3 - 8.5
• alcamo/dom: 0.16 - 0.18

Requires (Dev)

• phpunit/phpunit: ^9.5
• squizlabs/php_codesniffer: 3.*

Apache-2.0

• factory
• RDF
• datatype
• literal

Published on Packagist.org on 2026-07-09 08:31 UTC

README

namespace alcamo\rdf_literal_workbench;

use alcamo\rdf_literal\StringLiteral;
use alcamo\uri\FileUriFactory;

include $_composer_autoload_path ?? __DIR__ . '/../vendor/autoload.php';

$factory = new LiteralFactory();

$factory->getSchema()->addUris(
    [
        (new FileUriFactory)->create(
            dirname(__DIR__) . DIRECTORY_SEPARATOR . 'vendor'
                . DIRECTORY_SEPARATOR . 'alcamo'
                . DIRECTORY_SEPARATOR . 'dom'
                . DIRECTORY_SEPARATOR . 'xsd'
                . DIRECTORY_SEPARATOR . 'xhtml-datatypes-1.xsd'
        )
    ]
);

$ncNameType =
    $factory->getSchema()->getGlobalType(LiteralFactory::XH11D_NS . ' Pixels');

$literal1 = $factory->create(1024, $ncNameType);

echo "$literal1: class " . get_class($literal1) . PHP_EOL;

$typeMap = new LiteralTypeMap();

$typeMap->validateLiteral($literal1);

$literal2 = new StringLiteral('foo', LiteralFactory::XSD_NS . '#QName');

$typeMap->validateLiteral($literal2);

This example is contained in this package as a file in the bin directory. It will output

1024: class alcamo\rdf_literal\NonNegativeIntegerLiteral
PHP Fatal error:  Uncaught alcamo\exception\DataValidationFailed: Validation failed; literal datatype http://www.w3.org/2001/XMLSchema QName not derived from default datatype http://www.w3.org/2001/XMLSchema string in /home/rve/src/alcamo-rdf-literal-workbench/src/LiteralTypeMap.php:62

Unlike alcamo\rdf_literal\LiteralFactory, the class alcamo\rdf_literal_workbench\LiteralFactory contains an XML schema and hence is aware of the type hierarchy. Thus, the above call to create() creates an instance of NonNegativeIntegerLiteral since the factory knows that the simple type xh11d:Pixels is derived from xsd:NonNegativeInteger.

The class alcamo\rdf_literal\LiteralTypeMap, which contains an XML Schema as well, can be used to validate whether the datatype of a literal is actually supported by the literal class, i.e. derived from its defaut type. In the above example, $literal1 is valid while $literal2 is not. The literal classes themselves do not check this because they would need an XML schema for this.