rdbms: Avoid selectDB() call in LoadMonitor new connections

[mediawiki.git] / includes / api / ApiQuerySearch.php

<?php
/**
 *
 *
 * Created on July 30, 2007
 *
 * Copyright © 2007 Yuri Astrakhan "<Firstname><Lastname>@gmail.com"
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 * http://www.gnu.org/copyleft/gpl.html
 *
 * @file
 */

/**
 * Query module to perform full text search within wiki titles and content
 *
 * @ingroup API
 */
class ApiQuerySearch extends ApiQueryGeneratorBase {
        use SearchApi;

        /** @var array list of api allowed params */
        private $allowedParams;

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

        public function execute() {
                $this->run();
        }

        public function executeGenerator( $resultPageSet ) {
                $this->run( $resultPageSet );
        }

        /**
         * @param ApiPageSet $resultPageSet
         * @return void
         */
        private function run( $resultPageSet = null ) {
                global $wgContLang;
                $params = $this->extractRequestParams();

                // Extract parameters
                $query = $params['search'];
                $what = $params['what'];
                $interwiki = $params['interwiki'];
                $searchInfo = array_flip( $params['info'] );
                $prop = array_flip( $params['prop'] );

                // Create search engine instance and set options
                $search = $this->buildSearchEngine( $params );
                $search->setFeatureData( 'rewrite', (bool)$params['enablerewrites'] );
                $search->setFeatureData( 'interwiki', (bool)$interwiki );

                $query = $search->transformSearchTerm( $query );
                $query = $search->replacePrefixes( $query );

                // Perform the actual search
                if ( $what == 'text' ) {
                        $matches = $search->searchText( $query );
                } elseif ( $what == 'title' ) {
                        $matches = $search->searchTitle( $query );
                } elseif ( $what == 'nearmatch' ) {
                        // near matches must receive the user input as provided, otherwise
                        // the near matches within namespaces are lost.
                        $matches = $search->getNearMatcher( $this->getConfig() )
                                ->getNearMatchResultSet( $params['search'] );
                } else {
                        // We default to title searches; this is a terrible legacy
                        // of the way we initially set up the MySQL fulltext-based
                        // search engine with separate title and text fields.
                        // In the future, the default should be for a combined index.
                        $what = 'title';
                        $matches = $search->searchTitle( $query );

                        // Not all search engines support a separate title search,
                        // for instance the Lucene-based engine we use on Wikipedia.
                        // In this case, fall back to full-text search (which will
                        // include titles in it!)
                        if ( is_null( $matches ) ) {
                                $what = 'text';
                                $matches = $search->searchText( $query );
                        }
                }

                if ( $matches instanceof Status ) {
                        $status = $matches;
                        $matches = $status->getValue();
                } else {
                        $status = null;
                }

                if ( $status ) {
                        if ( $status->isOK() ) {
                                $this->getMain()->getErrorFormatter()->addMessagesFromStatus(
                                        $this->getModuleName(),
                                        $status
                                );
                        } else {
                                $this->dieStatus( $status );
                        }
                } elseif ( is_null( $matches ) ) {
                        $this->dieWithError( [ 'apierror-searchdisabled', $what ], "search-{$what}-disabled" );
                }

                if ( $resultPageSet === null ) {
                        $apiResult = $this->getResult();
                        // Add search meta data to result
                        if ( isset( $searchInfo['totalhits'] ) ) {
                                $totalhits = $matches->getTotalHits();
                                if ( $totalhits !== null ) {
                                        $apiResult->addValue( [ 'query', 'searchinfo' ],
                                                'totalhits', $totalhits );
                                }
                        }
                        if ( isset( $searchInfo['suggestion'] ) && $matches->hasSuggestion() ) {
                                $apiResult->addValue( [ 'query', 'searchinfo' ],
                                        'suggestion', $matches->getSuggestionQuery() );
                                $apiResult->addValue( [ 'query', 'searchinfo' ],
                                        'suggestionsnippet', $matches->getSuggestionSnippet() );
                        }
                        if ( isset( $searchInfo['rewrittenquery'] ) && $matches->hasRewrittenQuery() ) {
                                $apiResult->addValue( [ 'query', 'searchinfo' ],
                                        'rewrittenquery', $matches->getQueryAfterRewrite() );
                                $apiResult->addValue( [ 'query', 'searchinfo' ],
                                        'rewrittenquerysnippet', $matches->getQueryAfterRewriteSnippet() );
                        }
                }

                // Add the search results to the result
                $terms = $wgContLang->convertForSearchResult( $matches->termMatches() );
                $titles = [];
                $count = 0;
                $result = $matches->next();
                $limit = $params['limit'];

                while ( $result ) {
                        if ( ++$count > $limit ) {
                                // We've reached the one extra which shows that there are
                                // additional items to be had. Stop here...
                                $this->setContinueEnumParameter( 'offset', $params['offset'] + $params['limit'] );
                                break;
                        }

                        // Silently skip broken and missing titles
                        if ( $result->isBrokenTitle() || $result->isMissingRevision() ) {
                                $result = $matches->next();
                                continue;
                        }

                        if ( $resultPageSet === null ) {
                                $vals = $this->getSearchResultData( $result, $prop, $terms );
                                if ( $vals ) {
                                        // Add item to results and see whether it fits
                                        $fit = $apiResult->addValue( [ 'query', $this->getModuleName() ], null, $vals );
                                        if ( !$fit ) {
                                                $this->setContinueEnumParameter( 'offset', $params['offset'] + $count - 1 );
                                                break;
                                        }
                                }
                        } else {
                                $titles[] = $result->getTitle();
                        }

                        $result = $matches->next();
                }

                // Here we assume interwiki results do not count with
                // regular search results. We may want to reconsider this
                // if we ever return a lot of interwiki results or want pagination
                // for them.
                // Interwiki results inside main result set
                $canAddInterwiki = (bool)$params['enablerewrites'] && ( $resultPageSet === null );
                if ( $canAddInterwiki ) {
                        $this->addInterwikiResults( $matches, $apiResult, $prop, $terms, 'additional',
                                SearchResultSet::INLINE_RESULTS );
                }

                // Interwiki results outside main result set
                if ( $interwiki && $resultPageSet === null ) {
                        $this->addInterwikiResults( $matches, $apiResult, $prop, $terms, 'interwiki',
                                SearchResultSet::SECONDARY_RESULTS );
                }

                if ( $resultPageSet === null ) {
                        $apiResult->addIndexedTagName( [
                                'query', $this->getModuleName()
                        ], 'p' );
                } else {
                        $resultPageSet->setRedirectMergePolicy( function ( $current, $new ) {
                                if ( !isset( $current['index'] ) || $new['index'] < $current['index'] ) {
                                        $current['index'] = $new['index'];
                                }
                                return $current;
                        } );
                        $resultPageSet->populateFromTitles( $titles );
                        $offset = $params['offset'] + 1;
                        foreach ( $titles as $index => $title ) {
                                $resultPageSet->setGeneratorData( $title, [ 'index' => $index + $offset ] );
                        }
                }
        }

        /**
         * Assemble search result data.
         * @param SearchResult $result Search result
         * @param array        $prop Props to extract (as keys)
         * @param array        $terms Terms list
         * @return array|null Result data or null if result is broken in some way.
         */
        private function getSearchResultData( SearchResult $result, $prop, $terms ) {
                // Silently skip broken and missing titles
                if ( $result->isBrokenTitle() || $result->isMissingRevision() ) {
                        return null;
                }

                $vals = [];

                $title = $result->getTitle();
                ApiQueryBase::addTitleInfo( $vals, $title );
                $vals['pageid'] = $title->getArticleID();

                if ( isset( $prop['size'] ) ) {
                        $vals['size'] = $result->getByteSize();
                }
                if ( isset( $prop['wordcount'] ) ) {
                        $vals['wordcount'] = $result->getWordCount();
                }
                if ( isset( $prop['snippet'] ) ) {
                        $vals['snippet'] = $result->getTextSnippet( $terms );
                }
                if ( isset( $prop['timestamp'] ) ) {
                        $vals['timestamp'] = wfTimestamp( TS_ISO_8601, $result->getTimestamp() );
                }
                if ( isset( $prop['titlesnippet'] ) ) {
                        $vals['titlesnippet'] = $result->getTitleSnippet();
                }
                if ( isset( $prop['categorysnippet'] ) ) {
                        $vals['categorysnippet'] = $result->getCategorySnippet();
                }
                if ( !is_null( $result->getRedirectTitle() ) ) {
                        if ( isset( $prop['redirecttitle'] ) ) {
                                $vals['redirecttitle'] = $result->getRedirectTitle()->getPrefixedText();
                        }
                        if ( isset( $prop['redirectsnippet'] ) ) {
                                $vals['redirectsnippet'] = $result->getRedirectSnippet();
                        }
                }
                if ( !is_null( $result->getSectionTitle() ) ) {
                        if ( isset( $prop['sectiontitle'] ) ) {
                                $vals['sectiontitle'] = $result->getSectionTitle()->getFragment();
                        }
                        if ( isset( $prop['sectionsnippet'] ) ) {
                                $vals['sectionsnippet'] = $result->getSectionSnippet();
                        }
                }
                if ( isset( $prop['isfilematch'] ) ) {
                        $vals['isfilematch'] = $result->isFileMatch();
                }
                return $vals;
        }

        /**
         * Add interwiki results as a section in query results.
         * @param SearchResultSet $matches
         * @param ApiResult       $apiResult
         * @param array           $prop Props to extract (as keys)
         * @param array           $terms Terms list
         * @param string          $section Section name where results would go
         * @param int             $type Interwiki result type
         * @return int|null Number of total hits in the data or null if none was produced
         */
        private function addInterwikiResults(
                SearchResultSet $matches, ApiResult $apiResult, $prop,
                $terms, $section, $type
        ) {
                $totalhits = null;
                if ( $matches->hasInterwikiResults( $type ) ) {
                        foreach ( $matches->getInterwikiResults( $type ) as $interwikiMatches ) {
                                // Include number of results if requested
                                $totalhits += $interwikiMatches->getTotalHits();

                                $result = $interwikiMatches->next();
                                while ( $result ) {
                                        $title = $result->getTitle();
                                        $vals = $this->getSearchResultData( $result, $prop, $terms );

                                        $vals['namespace'] = $result->getInterwikiNamespaceText();
                                        $vals['title'] = $title->getText();
                                        $vals['url'] = $title->getFullURL();

                                        // Add item to results and see whether it fits
                                        $fit = $apiResult->addValue( [
                                                        'query',
                                                        $section . $this->getModuleName(),
                                                        $result->getInterwikiPrefix()
                                                ], null, $vals );

                                        if ( !$fit ) {
                                                // We hit the limit. We can't really provide any meaningful
                                                // pagination info so just bail out
                                                break;
                                        }

                                        $result = $interwikiMatches->next();
                                }
                        }
                        if ( $totalhits !== null ) {
                                $apiResult->addValue( [ 'query', $section . 'searchinfo' ], 'totalhits', $totalhits );
                                $apiResult->addIndexedTagName( [
                                        'query', $section . $this->getModuleName()
                                ], 'p' );
                        }
                }
                return $totalhits;
        }

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

        public function getAllowedParams() {
                if ( $this->allowedParams !== null ) {
                        return $this->allowedParams;
                }

                $this->allowedParams = $this->buildCommonApiParams() + [
                        'what' => [
                                ApiBase::PARAM_TYPE => [
                                        'title',
                                        'text',
                                        'nearmatch',
                                ]
                        ],
                        'info' => [
                                ApiBase::PARAM_DFLT => 'totalhits|suggestion|rewrittenquery',
                                ApiBase::PARAM_TYPE => [
                                        'totalhits',
                                        'suggestion',
                                        'rewrittenquery',
                                ],
                                ApiBase::PARAM_ISMULTI => true,
                        ],
                        'prop' => [
                                ApiBase::PARAM_DFLT => 'size|wordcount|timestamp|snippet',
                                ApiBase::PARAM_TYPE => [
                                        'size',
                                        'wordcount',
                                        'timestamp',
                                        'snippet',
                                        'titlesnippet',
                                        'redirecttitle',
                                        'redirectsnippet',
                                        'sectiontitle',
                                        'sectionsnippet',
                                        'isfilematch',
                                        'categorysnippet',
                                        'score', // deprecated
                                        'hasrelated', // deprecated
                                ],
                                ApiBase::PARAM_ISMULTI => true,
                                ApiBase::PARAM_HELP_MSG_PER_VALUE => [],
                                ApiBase::PARAM_DEPRECATED_VALUES => [
                                        'score' => true,
                                        'hasrelated' => true
                                ],
                        ],
                        'interwiki' => false,
                        'enablerewrites' => false,
                ];

                return $this->allowedParams;
        }

        public function getSearchProfileParams() {
                return [
                        'qiprofile' => [
                                'profile-type' => SearchEngine::FT_QUERY_INDEP_PROFILE_TYPE,
                                'help-message' => 'apihelp-query+search-param-qiprofile',
                        ],
                ];
        }

        protected function getExamplesMessages() {
                return [
                        'action=query&list=search&srsearch=meaning'
                                => 'apihelp-query+search-example-simple',
                        'action=query&list=search&srwhat=text&srsearch=meaning'
                                => 'apihelp-query+search-example-text',
                        'action=query&generator=search&gsrsearch=meaning&prop=info'
                                => 'apihelp-query+search-example-generator',
                ];
        }

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