/**
* This method sends a SPARQL query to the store.
*
* @param string $query The SPARQL query to send to the store.
* @param array $options optional It contains key-value pairs and should provide additional
* introductions for the store and/or its adapter(s).
* @return Result Returns result of the query. Its type depends on the type of the query.
* @throws \Exception If query is no string.
* @throws \Exception If query is malformed.
* @throws \Exception If query is a DELETE query and contains quads, where the graph of one quad is of type var
* @throws \Exception If a non-graph query contains no triples and quads.
* @todo handle multiple graphs in FROM clause
*/
public function query($query, array $options = array())
{
$queryObject = $this->queryFactory->createInstanceByQueryString($query);
$queryParts = $queryObject->getQueryParts();
// if a non-graph query was given, we assume triples or quads. If neither quads nor triples were found,
// throw an exception.
if (false === $queryObject->isGraphQuery() && false === isset($queryParts['triple_pattern']) && false === isset($queryParts['quad_pattern'])) {
throw new \Exception('Non-graph queries must have triples or quads.');
}
// execute query on the store
$result = $this->store->query($query);
/*
* special case: if you execute a SELECT COUNT(*) query, ARC2 will return the number of triples
instead of a result set
*/
$countCheck = preg_match('/selectcount\\([a-z*]\\)(from|where)/si', preg_replace('/\\s+/', '', $query));
if (1 == $countCheck) {
$variable = 'callret-0';
// build a set result, because the user expects it as result type because a SELECT query
// was sent.
$setResult = $this->resultFactory->createSetResult(array(array($variable => $this->nodeFactory->createLiteral($result, 'http://www.w3.org/2001/XMLSchema#int'))));
$setResult->setVariables(array($variable));
return $setResult;
/*
* ARC2 does not support quads, especially not in DELETE queries. The following code construct
* tries to close that gap by transforming the query in a one which ARC2 can understand.
*
* This part transform queries of the kind:
*
* DELETE WHERE {
* Graph <http://localhost/Saft/TestGraph/> {
* ?s ?p ?o .
* }
* }
*
* to SPARQL+ ones:
*
* DELETE FROM <http://localhost/Saft/TestGraph/> {
* ?s ?p ?o .
* }
* WHERE {
* ?s ?p ?o .
* }
*
*
* IMPORTANT: Please adapt
* https://github.com/SaftIng/safting.github.io/blob/master/doc/phpframework/addition/ARC2.md
* if you change the support for SPARQL 1.0/1.1 here!
*/
} elseif ($queryObject->isUpdateQuery() && isset($queryParts['quad_pattern']) && 'deleteWhere' === $queryParts['sub_type']) {
foreach ($queryParts['quad_pattern'] as $quad) {
if ('uri' != $quad['g_type']) {
throw new \Exception('The graph of a quad must be an URI here.');
}
// subject
$s = NodeUtils::createNodeInstance($this->nodeFactory, $quad['s'], $quad['s_type']);
$s = SparqlUtils::getNodeInSparqlFormat($s);
// predicate
$p = NodeUtils::createNodeInstance($this->nodeFactory, $quad['p'], $quad['p_type']);
$p = SparqlUtils::getNodeInSparqlFormat($p);
// object
$o = NodeUtils::createNodeInstance($this->nodeFactory, $quad['o'], $quad['o_type'], $quad['o_datatype'], $quad['o_lang']);
$o = SparqlUtils::getNodeInSparqlFormat($o);
return $this->query('DELETE FROM <' . $quad['g'] . '> {' . $s . ' ' . $p . ' ' . $o . ' }
WHERE {' . $s . ' ' . $p . ' ' . $o . ' }');
}
/*
* SELECT query
*/
} elseif ('selectQuery' === AbstractQuery::getQueryType($query)) {
/*
* For a SELECT query the result looks like:
*
* array(
* 'query_time' => 0.2
* 'query_type' => 'select',
* 'result' => array(
* 'variables' => array('s', 'o')
* 'rows' =>
* array(
* 's' => "http://s/"
* 's type' => 'uri',
* 'o' => '42',
* 'o type' => "literal"
* 'o datatype' => "http://www.w3.org/2001/XMLSchema#string"
* )
*/
$entries = array();
// go through all rows
foreach ($result['result']['rows'] as $row) {
$newEntry = array();
foreach ($result['result']['variables'] as $variable) {
// checks for variable type
// example: $row['s type']
switch ($row[$variable . ' type']) {
// ARC2 does not differenciate between typed literal and literal, like Virtuoso does
// for instance. You have to check for lang and datatype key by yourself.
case 'literal':
// if language is set
if (isset($row[$variable . ' lang'])) {
$newEntry[$variable] = $this->nodeFactory->createLiteral($row[$variable], 'http://www.w3.org/1999/02/22-rdf-syntax-ns#langString', $row[$variable . ' lang']);
// if datatype is set
} elseif (isset($row[$variable . ' datatype'])) {
$newEntry[$variable] = $this->nodeFactory->createLiteral($row[$variable], $row[$variable . ' datatype']);
// if neither one is set, we assume its a string and use xsd:string as datatype
} else {
$newEntry[$variable] = $this->nodeFactory->createLiteral($row[$variable], 'http://www.w3.org/2001/XMLSchema#string');
}
break;
case 'uri':
$newEntry[$variable] = $this->nodeFactory->createNamedNode($row[$variable]);
break;
}
}
$entries[] = $newEntry;
}
// Create and fill SetResult instance
$setResult = $this->resultFactory->createSetResult($entries);
$setResult->setVariables($result['result']['variables']);
return $setResult;
} else {
if ('askQuery' === AbstractQuery::getQueryType($query)) {
return $this->resultFactory->createValueResult($result['result']);
} else {
return $this->resultFactory->createEmptyResult();
}
}
}
public function testCreateNodeInstanceUri()
{
$node = NodeUtils::createNodeInstance(new NodeFactoryImpl(), 'http://foo', 'uri');
$this->assertEquals(new NamedNodeImpl('http://foo'), $node);
}