Jarves\Objects::getPrimaries PHP Method

    public function getPrimaries($objectId)
    {
        $objectDefinition = $this->getDefinition($objectId);
        $primaryFields = array();
        foreach ($objectDefinition->getFields() as $field) {
            if ($field->isPrimaryKey()) {
                $primaryFields[$field->getId()] = $field;
            }
        }
        return $primaryFields;
    }