wikimedia/mediawiki-extensions-CirrusSearch

<?php

namespace CirrusSearch\Search;

use Elastica\ResultSet as ElasticaResultSet;

/**
 * Result type for aggregations.
 */
class SingleAggResultsType implements ResultsType {
    /** @var string Name of aggregation */
    private $name;

    /** @param string $name Name of aggregation to return */
    public function __construct( $name ) {
        $this->name = $name;
    }

    /**
     * @return false|string|array corresponding to Elasticsearch source filtering syntax
     */
    public function getSourceFiltering() {
        return false;
    }

    public function getFields() {
        return [];
    }

    public function getHighlightingConfiguration( array $extraHighlightFields ) {
        return null;
    }

    /**
     * @param ElasticaResultSet $resultSet
     * @return mixed|null Type depends on the aggregation performed. For
     *  a sum this will return an integer.
     */
    public function transformElasticsearchResult( ElasticaResultSet $resultSet ) {
        $aggs = $resultSet->getAggregations();
        if ( isset( $aggs[$this->name] ) ) {
            return $aggs[$this->name]['value'];
        }
        return $this->createEmptyResult();
    }

    /**
     * @return null
     */
    public function createEmptyResult() {
        return null;
    }
}