1 files changed, 234 insertions, 0 deletions
diff --git a/www/wiki/extensions/SemanticMediaWiki/src/SPARQLStore/QueryEngine/XmlResponseParser.php b/www/wiki/extensions/SemanticMediaWiki/src/SPARQLStore/QueryEngine/XmlResponseParser.php
new file mode 100644
index 00000000..24182051
--- /dev/null
+++ b/www/wiki/extensions/SemanticMediaWiki/src/SPARQLStore/QueryEngine/XmlResponseParser.php
@@ -0,0 +1,234 @@
+<?php
+
+namespace SMW\SPARQLStore\QueryEngine;
+
+use SMW\SPARQLStore\Exception\XmlParserException;
+use SMW\SPARQLStore\HttpResponseParser;
+use SMWExpLiteral as ExpLiteral;
+use SMWExpResource as ExpResource;
+
+/**
+ * Class for parsing SPARQL results in XML format
+ *
+ * @license GNU GPL v2+
+ * @since 1.6
+ *
+ * @author Markus Krötzsch
+ */
+class XmlResponseParser implements HttpResponseParser {
+
+	/**
+	 * @var resource
+	 */
+	private $parser;
+
+	/**
+	 * Associative array mapping SPARQL variable names to column indices.
+	 * @var array of integer
+	 */
+	private $header;
+
+	/**
+	 * List of result rows. Individual entries can be null if a cell in the
+	 * SPARQL result table is empty (this is different from finding a blank
+	 * node).
+	 * @var array of array of (SMWExpElement or null)
+	 */
+	private $data;
+
+	/**
+	 * List of comment strings found in the XML file (without surrounding
+	 * markup, i.e. the actual string only).
+	 * @var array of string
+	 */
+	private $comments;
+
+	/**
+	 * Stack of open XML tags during parsing.
+	 * @var array of string
+	 */
+	private $xmlOpenTags;
+
+	/**
+	 * Integer index of the column that the current result binding fills.
+	 * @var integer
+	 */
+	private $xmlBindIndex;
+
+	/**
+	 * Datatype URI for the current literal, or empty if none.
+	 * @var string
+	 */
+	private $currentDataType;
+
+	/**
+	 * @since 2.0
+	 */
+	public function __construct() {
+		$this->parser = xml_parser_create();
+
+		xml_parser_set_option( $this->parser, XML_OPTION_SKIP_WHITE, 0 );
+		xml_parser_set_option( $this->parser, XML_OPTION_TARGET_ENCODING, 'UTF-8' );
+		xml_parser_set_option( $this->parser, XML_OPTION_CASE_FOLDING, 0 );
+		xml_set_object( $this->parser, $this );
+		xml_set_element_handler( $this->parser, 'handleOpenElement', 'handleCloseElement' );
+		xml_set_character_data_handler( $this->parser, 'handleCharacterData' );
+		xml_set_default_handler( $this->parser, 'handleDefault' );
+		//xml_set_start_namespace_decl_handler($parser, 'handleNsDeclaration' );
+	}
+
+	/**
+	 * @since 2.0
+	 */
+	public function __destruct() {
+		xml_parser_free( $this->parser );
+	}
+
+	/**
+	 * Parse the given XML result and return an RepositoryResult for
+	 * the contained data.
+	 *
+	 * @param string $response
+	 *
+	 * @return RepositoryResult
+	 * @throws XmlParserException
+	 */
+	public function parse( $response ) {
+
+		$this->xmlOpenTags = [];
+		$this->header = [];
+		$this->data = [];
+		$this->comments = [];
+
+		// Sesame can return "" result
+		if ( $response === '' ) {
+			$this->data = [ [ new ExpLiteral( 'false', 'http://www.w3.org/2001/XMLSchema#boolean' ) ] ];
+		}
+
+		// #626 Virtuoso
+		if ( $response == 'true' ) {
+			$this->data = [ [ new ExpLiteral( 'true', 'http://www.w3.org/2001/XMLSchema#boolean' ) ] ];
+		}
+
+		// #474 Virtuoso allows `false` to be a valid raw result
+		if ( $response === '' || $response == 'false' || $response == 'true' || is_bool( $response ) || $this->parseXml( $response ) ) {
+			return new RepositoryResult(
+				$this->header,
+				$this->data,
+				$this->comments
+			);
+		}
+
+		throw new XmlParserException(
+			$this->getLastError(),
+			$this->getLastLineNumber(),
+			$this->getLastColumnNumber()
+		);
+	}
+
+	private function parseXml( $xmlResultData ) {
+		return xml_parse( $this->parser, $xmlResultData, true );
+	}
+
+	private function getLastError() {
+		return xml_error_string( xml_get_error_code( $this->parser ) );
+	}
+
+	private function getLastLineNumber() {
+		return xml_get_current_line_number( $this->parser );
+	}
+
+	private function getLastColumnNumber() {
+		return xml_get_current_column_number ( $this->parser );
+	}
+
+	private function handleDefault( $parser, $data ) {
+		if ( substr( $data, 0, 4 ) == '<!--' ) {
+			$comment = substr( $data, 4, strlen( $data ) - 7 );
+			$this->comments[] = trim( $comment );
+		}
+	}
+
+	/**
+	 * @see xml_set_element_handler
+	 */
+	private function handleOpenElement( $parser, $elementTag, $attributes ) {
+
+		$this->currentDataType = '';
+
+		$prevTag = end( $this->xmlOpenTags );
+		$this->xmlOpenTags[] = $elementTag;
+
+		switch ( $elementTag ) {
+			case 'binding' && ( $prevTag == 'result' ):
+					if ( ( array_key_exists( 'name', $attributes ) ) &&
+					     ( array_key_exists( $attributes['name'], $this->header ) ) ) {
+						 $this->xmlBindIndex = $this->header[$attributes['name']];
+					}
+				break;
+			case 'result' && ( $prevTag == 'results' ):
+				$this->data[] = array_fill( 0, count( $this->header ), null );
+				break;
+			case  'literal' && ( $prevTag == 'binding' ):
+				if ( array_key_exists( 'datatype', $attributes ) ) {
+					$this->currentDataType = $attributes['datatype'];
+				}
+				/// TODO handle xml:lang attributes here as well?
+				break;
+			case  'variable' && ( $prevTag == 'head' ):
+				if ( array_key_exists( 'name', $attributes ) ) {
+					$this->header[$attributes['name']] = count( $this->header );
+				}
+				break;
+		}
+	}
+
+	/**
+	 * @see xml_set_element_handler
+	 */
+	private function handleCloseElement( $parser, $elementTag ) {
+		array_pop( $this->xmlOpenTags );
+	}
+
+	/**
+	 * @see xml_set_character_data_handler
+	 */
+	private function handleCharacterData( $parser, $characterData ) {
+
+		$prevTag = end( $this->xmlOpenTags );
+		$rowcount = count( $this->data ) - 1;
+
+		// UTF-8 is being split therefore concatenate the string (use row as indicator
+		// to detect a sliced string)
+		if ( isset( $this->data[$rowcount] ) && ( $element = end( $this->data[$rowcount] ) ) !== null ) {
+			switch ( $prevTag ) {
+				case 'uri':
+					$characterData = $element->getUri() . $characterData;
+					break;
+				case 'literal':
+					$characterData = $element->getLexicalForm() . $characterData;
+			}
+		}
+
+		switch ( $prevTag ) {
+			case 'uri':
+				$this->data[$rowcount][$this->xmlBindIndex] = new ExpResource( $characterData );
+				break;
+			case 'literal':
+				$this->data[$rowcount][$this->xmlBindIndex] = new ExpLiteral( $characterData, $this->currentDataType );
+				break;
+			case 'bnode':
+				$this->data[$rowcount][$this->xmlBindIndex] = new ExpResource( '_' . $characterData );
+				break;
+			case 'boolean':
+				// no "results" in this case
+				$literal = new ExpLiteral( $characterData, 'http://www.w3.org/2001/XMLSchema#boolean' );
+
+				// ?? Really !!
+				$this->data = [ [ $literal ] ];
+				$this->header = [ '' => 0 ];
+				break;
+		}
+	}
+
+}