parseGrouping example

if (!$criteria->getGroupFields()) {
            $array = $search->toArray();
            $array['timeout'] = $this->timeout;

            return $array;
        }

        $aggregation = $this->buildTotalCountAggregation($criteria, $definition, $context);

        $search->addAggregation($aggregation);
        $array = $search->toArray();
        $array['collapse'] = $this->parseGrouping($criteria->getGroupFields(), $definition, $context);
        $array['timeout'] = $this->timeout;

        return $array;
    }

    /** * @param FieldGrouping[] $groupings * * @return array{field: string, inner_hits?: array{name: string}} */
    private function parseGrouping(array $groupings, EntityDefinition $definition, Context $context): array
    {