1
|
|
|
<?php declare(strict_types = 1); |
2
|
|
|
|
3
|
|
|
namespace JSKOS\RDF; |
4
|
|
|
|
5
|
|
|
use JSKOS\PrettyJsonSerializable; |
6
|
|
|
use JSKOS\Set; |
7
|
|
|
use ML\JsonLD\JsonLD; |
8
|
|
|
use ML\JsonLD\NQuads; |
9
|
|
|
use ML\IRI\IRI; |
10
|
|
|
use ML\JsonLD\LanguageTaggedString; |
11
|
|
|
use EasyRdf_Graph; |
12
|
|
|
|
13
|
|
|
/** |
14
|
|
|
* EasyRdf parser to support JSON-LD to RDF conversion. |
15
|
|
|
* |
16
|
|
|
* Bridges PHP packages EasyRDF and json-ld. |
17
|
|
|
*/ |
18
|
|
|
class Parser extends \EasyRdf_Parser |
19
|
|
|
{ |
20
|
|
|
protected $context; |
21
|
|
|
|
22
|
|
|
/** |
23
|
|
|
* Parse JSKOS Resources to RDF. |
24
|
|
|
*/ |
25
|
|
|
public function parseJSKOS(PrettyJsonSerializable $jskos): EasyRdf_Graph |
26
|
|
|
{ |
27
|
|
|
if (!$this->context) { |
28
|
|
|
$this->context = json_decode(file_get_contents(__DIR__.'/jskos-context.json')); |
29
|
|
|
} |
30
|
|
|
|
31
|
|
|
if ($jskos instanceof Set) { |
32
|
|
|
$json = '{"@graph":'.json_encode($jskos->jsonLDSerialize('', true)).'}'; |
33
|
|
|
} else { |
34
|
|
|
$json = json_encode($jskos->jsonLDSerialize('', true)); |
35
|
|
|
} |
36
|
|
|
|
37
|
|
|
$rdf = JsonLD::toRdf($json, ['expandContext' => $this->context]); |
38
|
|
|
# TODO: catch (\ML\JsonLD\Exception\JsonLdException $e) |
39
|
|
|
|
40
|
|
|
$graph = new EasyRdf_Graph(); |
41
|
|
|
$this->parse($graph, $rdf); |
42
|
|
|
|
43
|
|
|
return $graph; |
44
|
|
|
} |
45
|
|
|
|
46
|
|
|
/** |
47
|
|
|
* Parse Quads as returned by JsonLD. |
48
|
|
|
*/ |
49
|
|
|
public function parse($graph, $data, $format = 'jsonld', $baseUri = null) |
50
|
|
|
{ |
51
|
|
|
parent::checkParseParams($graph, $data, $format, $baseUri); |
52
|
|
|
|
53
|
|
|
foreach ($data as $quad) { |
54
|
|
|
$subject = (string)$quad->getSubject(); |
55
|
|
|
|
56
|
|
|
if ('_:' === substr($subject, 0, 2)) { |
57
|
|
|
$subject = $this->remapBnode($subject); |
58
|
|
|
} |
59
|
|
|
|
60
|
|
|
$predicate = (string)$quad->getProperty(); |
61
|
|
|
|
62
|
|
|
if ($quad->getObject() instanceof IRI) { |
63
|
|
|
$object = [ |
64
|
|
|
'type' => 'uri', |
65
|
|
|
'value' => (string)$quad->getObject() |
66
|
|
|
]; |
67
|
|
|
|
68
|
|
|
if ('_:' === substr($object['value'], 0, 2)) { |
69
|
|
|
$object = [ |
70
|
|
|
'type' => 'bnode', |
71
|
|
|
'value' => $this->remapBnode($object['value']) |
72
|
|
|
]; |
73
|
|
|
} |
74
|
|
|
} else { |
75
|
|
|
$object = [ |
76
|
|
|
'type' => 'literal', |
77
|
|
|
'value' => $quad->getObject()->getValue() |
78
|
|
|
]; |
79
|
|
|
|
80
|
|
|
if ($quad->getObject() instanceof LanguageTaggedString) { |
81
|
|
|
$object['lang'] = $quad->getObject()->getLanguage(); |
82
|
|
|
} else { |
83
|
|
|
$object['datatype'] = $quad->getObject()->getType(); |
84
|
|
|
} |
85
|
|
|
} |
86
|
|
|
|
87
|
|
|
$this->addTriple($subject, $predicate, $object); |
88
|
|
|
} |
89
|
|
|
} |
90
|
|
|
} |
91
|
|
|
|