ApiQueryExternalLinks.php

Go to the documentation of this file.

<?php
class ApiQueryExternalLinks extends ApiQueryBase {

    public function __construct( ApiQuery $query, $moduleName ) {
        parent::__construct( $query, $moduleName, 'el' );
    }

    public function execute() {
        if ( $this->getPageSet()->getGoodTitleCount() == 0 ) {
            return;
        }

        $params = $this->extractRequestParams();

        $query = $params['query'];
        $protocol = ApiQueryExtLinksUsage::getProtocolPrefix( $params['protocol'] );

        $this->addFields( [
            'el_from',
            'el_to'
        ] );

        $this->addTables( 'externallinks' );
        $this->addWhereFld( 'el_from', array_keys( $this->getPageSet()->getGoodTitles() ) );

        $whereQuery = $this->prepareUrlQuerySearchString( $query, $protocol );

        if ( $whereQuery !== null ) {
            $this->addWhere( $whereQuery );
        }

        // Don't order by el_from if it's constant in the WHERE clause
        if ( count( $this->getPageSet()->getGoodTitles() ) != 1 ) {
            $this->addOption( 'ORDER BY', 'el_from' );
        }

        // If we're querying all protocols, use DISTINCT to avoid repeating protocol-relative links twice
        if ( $protocol === null ) {
            $this->addOption( 'DISTINCT' );
        }

        $this->addOption( 'LIMIT', $params['limit'] + 1 );
        $offset = isset( $params['offset'] ) ? $params['offset'] : 0;
        if ( $offset ) {
            $this->addOption( 'OFFSET', $params['offset'] );
        }

        $res = $this->select( __METHOD__ );

        $count = 0;
        foreach ( $res as $row ) {
            if ( ++$count > $params['limit'] ) {
                // We've reached the one extra which shows that
                // there are additional pages to be had. Stop here...
                $this->setContinueEnumParameter( 'offset', $offset + $params['limit'] );
                break;
            }
            $entry = [];
            $to = $row->el_to;
            // expand protocol-relative urls
            if ( $params['expandurl'] ) {
                $to = wfExpandUrl( $to, PROTO_CANONICAL );
            }
            ApiResult::setContentValue( $entry, 'url', $to );
            $fit = $this->addPageSubItem( $row->el_from, $entry );
            if ( !$fit ) {
                $this->setContinueEnumParameter( 'offset', $offset + $count - 1 );
                break;
            }
        }
    }

    public function getCacheMode( $params ) {
        return 'public';
    }

    public function getAllowedParams() {
        return [
            'limit' => [
                ApiBase::PARAM_DFLT => 10,
                ApiBase::PARAM_TYPE => 'limit',
                ApiBase::PARAM_MIN => 1,
                ApiBase::PARAM_MAX => ApiBase::LIMIT_BIG1,
                ApiBase::PARAM_MAX2 => ApiBase::LIMIT_BIG2
            ],
            'offset' => [
                ApiBase::PARAM_TYPE => 'integer',
                ApiBase::PARAM_HELP_MSG => 'api-help-param-continue',
            ],
            'protocol' => [
                ApiBase::PARAM_TYPE => ApiQueryExtLinksUsage::prepareProtocols(),
                ApiBase::PARAM_DFLT => '',
            ],
            'query' => null,
            'expandurl' => false,
        ];
    }

    protected function getExamplesMessages() {
        return [
            'action=query&prop=extlinks&titles=Main%20Page'
                => 'apihelp-query+extlinks-example-simple',
        ];
    }

    public function getHelpUrls() {
        return 'https://www.mediawiki.org/wiki/API:Extlinks';
    }
}