public static function build_restful_url($url, $params)
{
$url .= "?";
foreach ($params as $key => $value) {
$url .= "{$key}=" . SparqlUtil::encode($value) . "&";
}
return $url;
}
public function getData()
{
global $sparqlProxyIP, $sparqlProxyPort, $sparqlEndpointConfiguration;
$data = false;
$type = false;
if (isset($this->parameters[$sparqlEndpointConfiguration["output_type_parameter"]])) {
$type = $this->parameters[$sparqlEndpointConfiguration["output_type_parameter"]];
} else {
$type = $sparqlEndpointConfiguration["default_type"];
}
$url = $this->getEndpointRequestUrlForType($type);
$query_output = SparqlUtil::readQueryOutput($url, $sparqlProxyIP, $sparqlProxyPort, $type);
switch ($type) {
case "json":
$data = SparqlUtil::parse_json($query_output);
break;
default:
$data = SparqlUtil::parse_csv($query_output);
}
return $data;
}
function execute($par)
{
global $wgRequest, $wgOut, $sparqlEndpointConfiguration;
$request = $wgRequest->getValues();
if (is_null($wgRequest->getVal("query"))) {
// if no query provided - show the form page
$url = $this->getTitle()->getLinkUrl();
$formHTML = "<form action=\"" . $url . "\" method=\"get\">" . "<textarea name=\"query\" rows=\"40\">" . SparqlUtil::createPrefixes() . "select * where {\n" . "?x ?y ?z .\n" . "} limit 10" . "</textarea>" . "<div><select name=\"" . $sparqlEndpointConfiguration["output_type_parameter"] . "\">" . "<option value=\"" . SparqlExtension::$XML_TYPE . "\">XML</option>" . "<option value=\"" . SparqlExtension::$JSON_TYPE . "\">JSON</option>" . "<option value=\"" . SparqlExtension::$TEXT_TYPE . "\" selected=\"true\">TEXT</option>" . "<option value=\"" . SparqlExtension::$CSV_TYPE . "\">CSV</option>" . "<option value=\"" . SparqlExtension::$TSV_TYPE . "\">TSV</option>" . "<option value=\"" . SparqlExtension::$GDS_TYPE . "\">GOOGLE-VIS</option>" . "<option value=\"" . SparqlExtension::$SR_TYPE . "\">SEMANTIC REPORT</option>" . "</select><input type=\"submit\" value=\"Get Results\" /></form></div>";
$this->setHeaders();
$wgOut->addHTML($formHTML);
} else {
$sparql_url = $sparqlEndpointConfiguration["service_url"];
$response = "";
$header = "";
$output = isset($request["output"]) ? $request["output"] : "xml";
switch (strtolower($output)) {
case "xml":
$url = SparqlUtil::build_restful_url($sparql_url, $request);
$opts = array('http' => array('method' => 'GET', 'header' => 'Accept: application/sparql-results+xml, application/rdf+xml, application/xml'));
$context = stream_context_create($opts);
$response = file_get_contents($url, false, $context);
$header = "Content-type: application/xml; charset=utf-8";
break;
case "gds":
$url = SparqlUtil::build_restful_url($sparql_url, $request);
$inputparams = array();
if (isset($request["tqx"])) {
$inputparams["tqx"] = $request["tqx"];
}
$response = $this->xslt_transform($url, SparqlExtension::$GDS_XSL_URL, $inputparams);
$header = "Content-type: application/x-javascript; charset=utf-8";
break;
case "json":
$url = SparqlUtil::build_restful_url($sparql_url, $request);
$opts = array('http' => array('method' => 'GET', 'header' => 'Accept: application/sparql-results+json, application/rdf+json, application/json'));
$context = stream_context_create($opts);
$response = file_get_contents($url, false, $context);
$header = "Content-type: application/json; charset=utf-8";
break;
case "text":
$url = SparqlUtil::build_restful_url($sparql_url, $request);
$opts = array('http' => array('method' => 'GET', 'header' => 'Accept: text/plain, text/*, */*'));
$context = stream_context_create($opts);
$response = file_get_contents($url, false, $context);
$header = "Content-type: text/plain; charset=utf-8";
break;
case "csv":
$url = SparqlUtil::build_restful_url($sparql_url, $request);
$opts = array('http' => array('method' => 'GET', 'header' => 'Accept: text/csv, text/*, */*'));
$context = stream_context_create($opts);
$response = file_get_contents($url, false, $context);
$header = "Content-type: text/csv; charset=utf-8";
break;
case "tsv":
$url = SparqlUtil::build_restful_url($sparql_url, $request);
$opts = array('http' => array('method' => 'GET', 'header' => 'Accept: text/tsv, text/*, */*'));
$context = stream_context_create($opts);
$response = file_get_contents($url, false, $context);
$header = "Content-type: text/tsv; charset=utf-8";
break;
case "semantic-reports":
$request["endpoint"] = $sparql_url;
$request["view"] = "create";
$url = SparqlUtil::build_restful_url("http://semanticreports.com/reports/", $request);
//$response = file_get_contents($url);
$header = "Location: " . $url;
break;
default:
$url = SparqlUtil::build_restful_url($sparql_url, $request);
$opts = array('http' => array('method' => 'GET', 'header' => 'Accept: application/sparql-results+xml, application/rdf+xml, application/xml'));
$context = stream_context_create($opts);
$response = file_get_contents($url, false, $context);
$header = "Content-type: application/xml; charset=utf-8";
break;
}
$wgOut->disable();
header($header);
print $response;
}
}
