1 files changed, 333 insertions, 0 deletions
diff --git a/www/wiki/extensions/SemanticMediaWiki/src/SPARQLStore/TurtleTriplesBuilder.php b/www/wiki/extensions/SemanticMediaWiki/src/SPARQLStore/TurtleTriplesBuilder.php
new file mode 100644
index 00000000..fa6e9659
--- /dev/null
+++ b/www/wiki/extensions/SemanticMediaWiki/src/SPARQLStore/TurtleTriplesBuilder.php
@@ -0,0 +1,333 @@
+<?php
+
+namespace SMW\SPARQLStore;
+
+use Onoi\Cache\Cache;
+use SMW\ApplicationFactory;
+use SMW\DIWikiPage;
+use SMW\Exporter\Element;
+use SMW\Exporter\Element\ExpElement;
+use SMW\Exporter\Element\ExpNsResource;
+use SMW\Exporter\Element\ExpResource;
+use SMW\SemanticData;
+use SMWExpData as ExpData;
+use SMWExporter as Exporter;
+use SMWTurtleSerializer as TurtleSerializer;
+
+/**
+ * @license GNU GPL v2+
+ * @since 2.0
+ *
+ * @author Markus Krötzsch
+ * @author mwjames
+ */
+class TurtleTriplesBuilder {
+
+	/**
+	 * ID used for the InMemoryPoolCache
+	 */
+	const POOLCACHE_ID = 'sparql.turtle.triplesbuilder';
+
+	/**
+	 * @var SemanticData
+	 */
+	private $semanticData = null;
+
+	/**
+	 * @var RepositoryRedirectLookup
+	 */
+	private $repositoryRedirectLookup = null;
+
+	/**
+	 * @var null|string
+	 */
+	private $triples = null;
+
+	/**
+	 * @var array
+	 */
+	private $prefixes = [];
+
+	/**
+	 * @var boolean
+	 */
+	private $hasTriplesForUpdate = false;
+
+	/**
+	 * @var integer
+	 */
+	private $triplesChunkSize = 80;
+
+	/**
+	 * @var Cache
+	 */
+	private $dataItemExportInMemoryCache;
+
+	/**
+	 * @since 2.0
+	 *
+	 * @param RepositoryRedirectLookup $repositoryRedirectLookup
+	 * @param Cache|null $cache
+	 */
+	public function __construct( RepositoryRedirectLookup $repositoryRedirectLookup, Cache $cache = null ) {
+		$this->repositoryRedirectLookup = $repositoryRedirectLookup;
+		$this->dataItemExportInMemoryCache = ApplicationFactory::getInstance()->getInMemoryPoolCache()->getPoolCacheById( self::POOLCACHE_ID );
+	}
+
+	/**
+	 * @since 2.3
+	 *
+	 * @param integer $chunkSize
+	 */
+	public function setTriplesChunkSize( $triplesChunkSize ) {
+		$this->triplesChunkSize = (int)$triplesChunkSize;
+	}
+
+	/**
+	 * @since 2.0
+	 *
+	 * @param SemanticData $semanticData
+	 */
+	public function doBuildTriplesFrom( SemanticData $semanticData ) {
+
+		$this->hasTriplesForUpdate = false;
+		$this->triples  = '';
+		$this->prefixes = [];
+
+		$this->doSerialize( $semanticData );
+	}
+
+	/**
+	 * @since 2.0
+	 *
+	 * @return boolean
+	 */
+	public function hasTriples() {
+		return $this->hasTriplesForUpdate;
+	}
+
+	/**
+	 * @since 2.3
+	 *
+	 * @return string
+	 */
+	public function getTriples() {
+		return $this->triples === null ? '' : $this->triples;
+	}
+
+	/**
+	 * Split the triples into group of chunks as it can happen that some subjects
+	 * contain SPARQL strings that exceed 1800 lines which may reach the capacity
+	 * limit of a RespositoryConnector (#1110).
+	 *
+	 * @since 2.3
+	 *
+	 * @return array
+	 */
+	public function getChunkedTriples() {
+
+		$chunkedTriples = [];
+
+		if ( $this->triples === null ) {
+			return $chunkedTriples;
+		}
+
+		if ( strpos( $this->triples, " ." ) === false ) {
+			return $chunkedTriples;
+		}
+
+		$triplesArrayChunks = array_chunk(
+			explode( " .", $this->triples ), $this->triplesChunkSize
+		);
+
+		foreach( $triplesArrayChunks as $triplesChunk ) {
+			$chunkedTriples[] = implode( " .", $triplesChunk ) . "\n";
+		}
+
+		return $chunkedTriples;
+	}
+
+	/**
+	 * @since 2.0
+	 *
+	 * @return array
+	 */
+	public function getPrefixes() {
+		return $this->prefixes;
+	}
+
+	/**
+	 * @since 2.0
+	 */
+	public static function reset() {
+		TurtleSerializer::reset();
+	}
+
+	private function doSerialize( SemanticData $semanticData ) {
+
+		$expDataArray = $this->prepareUpdateExpData( $semanticData );
+
+		if ( count( $expDataArray ) > 0 ) {
+
+			$this->hasTriplesForUpdate = true;
+
+			$turtleSerializer = new TurtleSerializer( true );
+			$turtleSerializer->startSerialization();
+
+			foreach ( $expDataArray as $expData ) {
+				$turtleSerializer->serializeExpData( $expData );
+			}
+
+			$turtleSerializer->finishSerialization();
+
+			$this->triples = $turtleSerializer->flushContent();
+			$this->prefixes = $turtleSerializer->flushSparqlPrefixes();
+		}
+	}
+
+	/**
+	 * Prepare an array of SMWExpData elements that should be written to
+	 * the SPARQL store. The result is empty if no updates should be done.
+	 * Note that this is different from writing an SMWExpData element that
+	 * has no content.
+	 * Otherwise, the first SMWExpData object in the array is a translation
+	 * of the given input data, but with redirects resolved. Further
+	 * SMWExpData objects might be included in the resulting list to
+	 * capture necessary stub declarations for objects that do not have
+	 * any data in the RDF store yet.
+	 *
+	 * @since 1.6
+	 *
+	 * @param SemanticData $semanticData
+	 *
+	 * @return array of SMWExpData
+	 */
+	private function prepareUpdateExpData( SemanticData $semanticData ) {
+
+		$result = [];
+
+		$expData = Exporter::getInstance()->makeExportData( $semanticData );
+		$newExpData = $this->expandUpdateExpData( $expData, $result, false );
+		array_unshift( $result, $newExpData );
+
+		return $result;
+	}
+
+	/**
+	 * Find a normalized representation of the given SMWExpElement that can
+	 * be used in an update of the stored data. Normalization uses
+	 * redirects. The type of the ExpElement might change, especially into
+	 * SMWExpData in order to store auxiliary properties.
+	 * Moreover, the method records any auxiliary data that should be
+	 * written to the store when including this SMWExpElement into updates.
+	 * This auxiliary data is collected in a call-by-ref array.
+	 *
+	 * @since 1.6
+	 *
+	 * @param Element $expElement object containing the update data
+	 * @param $auxiliaryExpData array of SMWExpData
+	 *
+	 * @return ExpElement
+	 */
+	private function expandUpdateExpElement( Element $expElement, array &$auxiliaryExpData ) {
+
+		if ( $expElement instanceof ExpResource ) {
+			return $this->expandUpdateExpResource( $expElement, $auxiliaryExpData );
+		}
+
+		if ( $expElement instanceof ExpData ) {
+			return $this->expandUpdateExpData( $expElement, $auxiliaryExpData, true );
+		}
+
+		return $expElement;
+	}
+
+	/**
+	 * Find a normalized representation of the given SMWExpResource that can
+	 * be used in an update of the stored data. Normalization uses
+	 * redirects. The type of the ExpElement might change, especially into
+	 * SMWExpData in order to store auxiliary properties.
+	 * Moreover, the method records any auxiliary data that should be
+	 * written to the store when including this SMWExpElement into updates.
+	 * This auxiliary data is collected in a call-by-ref array.
+	 *
+	 * @since 1.6
+	 *
+	 * @param ExpResource $expResource object containing the update data
+	 * @param $auxiliaryExpData array of SMWExpData
+	 *
+	 * @return ExpElement
+	 */
+	private function expandUpdateExpResource( ExpResource $expResource, array &$auxiliaryExpData ) {
+
+		$exists = true;
+
+		if ( $expResource instanceof ExpNsResource ) {
+			$elementTarget = $this->repositoryRedirectLookup->findRedirectTargetResource( $expResource, $exists );
+		} else {
+			$elementTarget = $expResource;
+		}
+
+		if ( !$exists && $elementTarget->getDataItem() instanceof DIWikiPage && $elementTarget->getDataItem()->getDBKey() !== '' ) {
+
+			$diWikiPage = $elementTarget->getDataItem();
+			$hash = $diWikiPage->getHash();
+
+			if ( !$this->dataItemExportInMemoryCache->contains( $hash ) ) {
+				$this->dataItemExportInMemoryCache->save( $hash, Exporter::getInstance()->makeExportDataForSubject( $diWikiPage, true ) );
+			}
+
+			$auxiliaryExpData[$hash] = $this->dataItemExportInMemoryCache->fetch( $hash );
+		}
+
+		return $elementTarget;
+	}
+
+	/**
+	 * Find a normalized representation of the given SMWExpData that can
+	 * be used in an update of the stored data. Normalization uses
+	 * redirects.
+	 * Moreover, the method records any auxiliary data that should be
+	 * written to the store when including this SMWExpElement into updates.
+	 * This auxiliary data is collected in a call-by-ref array.
+	 *
+	 * @since 1.6
+	 * @param ExpData $expData object containing the update data
+	 * @param $auxiliaryExpData array of SMWExpData
+	 * @param $expandSubject boolean controls if redirects/auxiliary data should also be sought for subject
+	 *
+	 * @return ExpData
+	 */
+	private function expandUpdateExpData( ExpData $expData, array &$auxiliaryExpData, $expandSubject ) {
+
+		$subjectExpResource = $expData->getSubject();
+
+		if ( $expandSubject ) {
+
+			$expandedExpElement = $this->expandUpdateExpElement( $subjectExpResource, $auxiliaryExpData );
+
+			if ( $expandedExpElement instanceof ExpData ) {
+				$newExpData = $expandedExpElement;
+			} else { // instanceof SMWExpResource
+				$newExpData = new ExpData( $subjectExpResource );
+			}
+		} else {
+			$newExpData = new ExpData( $subjectExpResource );
+		}
+
+		foreach ( $expData->getProperties() as $propertyResource ) {
+
+			$propertyTarget = $this->expandUpdateExpElement( $propertyResource, $auxiliaryExpData );
+
+			foreach ( $expData->getValues( $propertyResource ) as $element ) {
+				$newExpData->addPropertyObjectValue(
+					$propertyTarget,
+					$this->expandUpdateExpElement( $element, $auxiliaryExpData )
+				);
+			}
+		}
+
+		return $newExpData;
+	}
+
+}