public static function ExtractExternalId($data, $singleResult = false, $CourseExtension = '', $ExternalIdExtension = '', $isResult = true)
{
// generates an assoc array of courses by using a defined list of
// its attributes
$course = DBJson::getObjectsByAttributes($data, Course::getDBPrimaryKey(), Course::getDBConvert(), $CourseExtension);
// generates an assoc array of external IDs by using a defined list of
// its attributes
$externalIds = DBJson::getObjectsByAttributes($data, ExternalId::getDBPrimaryKey(), ExternalId::getDBConvert(), $ExternalIdExtension);
// concatenates the external IDs and the associated courses
$res = DBJson::concatObjectListsSingleResult($data, $externalIds, ExternalId::getDBPrimaryKey(), ExternalId::getDBConvert()['EX_course'], $course, Course::getDBPrimaryKey(), $CourseExtension, $ExternalIdExtension);
if ($isResult) {
// to reindex
$res = array_values($res);
$res = ExternalId::decodeExternalId($res, false);
if ($singleResult == true) {
// only one object as result
if (count($res) > 0) {
$res = $res[0];
}
}
}
return $res;
}
