private function getRelationList($mapping, $suffix)
    {
        if (!isset($mapping['embed'.$suffix]) && !isset($mapping['reference'.$suffix])) {
            return [];
        }

        $relations = [];
        if (isset($mapping['embed'.$suffix])) {
            $relations = array_merge($relations, $mapping['embed'.$suffix]);
        }
        if (isset($mapping['reference'.$suffix])) {
            $relations = array_merge($relations, $mapping['reference'.$suffix]);
        }

        return array_map(
            function ($key, $value) {
                return [
                    'name' => $key,
                    'type' => $value['targetDocument']
                ];
            },
            array_keys($relations),
            $relations
        );
    }