ApiQueryExternalLinks.php

Go to the documentation of this file.

<?php
class ApiQueryExternalLinks extends ApiQueryBase {

        public function __construct( $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( array(
                        '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 = array();
                        $to = $row->el_to;
                        // expand protocol-relative urls
                        if( $params['expandurl'] ) {
                                $to = wfExpandUrl( $to, PROTO_CANONICAL );
                        }
                        ApiResult::setContent( $entry, $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 array(
                        'limit' => array(
                                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' => array(
                                ApiBase::PARAM_TYPE => 'integer'
                        ),
                        'protocol' => array(
                                ApiBase::PARAM_TYPE => ApiQueryExtLinksUsage::prepareProtocols(),
                                ApiBase::PARAM_DFLT => '',
                        ),
                        'query' => null,
                        'expandurl' => false,
                );
        }

        public function getParamDescription() {
                $p = $this->getModulePrefix();
                return array(
                        'limit' => 'How many links to return',
                        'offset' => 'When more results are available, use this to continue',
                        'protocol' => array(
                                "Protocol of the url. If empty and {$p}query set, the protocol is http.",
                                "Leave both this and {$p}query empty to list all external links"
                        ),
                        'query' => 'Search string without protocol. Useful for checking whether a certain page contains a certain external url',
                        'expandurl' => 'Expand protocol-relative urls with the canonical protocol',
                );
        }

        public function getResultProperties() {
                return array(
                        '' => array(
                                '*' => 'string'
                        )
                );
        }

        public function getDescription() {
                return 'Returns all external urls (not interwikis) from the given page(s)';
        }

        public function getPossibleErrors() {
                return array_merge( parent::getPossibleErrors(), array(
                        array( 'code' => 'bad_query', 'info' => 'Invalid query' ),
                ) );
        }

        public function getExamples() {
                return array(
                        'api.php?action=query&prop=extlinks&titles=Main%20Page' => 'Get a list of external links on the [[Main Page]]',
                );
        }

        public function getHelpUrls() {
                return 'https://www.mediawiki.org/wiki/API:Properties#extlinks_.2F_el';
        }
}