ApiQueryExtracts.php

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<?php
 
namespace TextExtracts;
 
use ApiBase;
use ApiMain;
use ApiQueryBase;
use BagOStuff;
use Config;
use FauxRequest;
use MediaWiki\Logger\LoggerFactory;
use MediaWiki\MediaWikiServices;
use MWTidy;
 
use ParserOptions;
use Title;
use ApiUsageException;
use User;
use WikiPage;
 
class ApiQueryExtracts extends ApiQueryBase {
 
    const CACHE_VERSION = 2;
 
    const PREFIX = 'ex';
 
    private $params;
    private $config;
 
    // TODO: Allow extensions to hook into this to opt-in.
    // This is partly for security reasons; see T107170.
    private $supportedContentModels = [ 'wikitext' ];
 
    public function __construct( $query, $moduleName, Config $conf ) {
        parent::__construct( $query, $moduleName, self::PREFIX );
        $this->config = $conf;
    }
 
    public function execute() {
        $titles = $this->getPageSet()->getGoodTitles();
        if ( $titles === [] ) {
            return;
        }
        $isXml = $this->getMain()->isInternalMode()
            || $this->getMain()->getPrinter()->getFormat() == 'XML';
        $result = $this->getResult();
        $params = $this->params = $this->extractRequestParams();
        $this->requireMaxOneParameter( $params, 'chars', 'sentences' );
        $continue = 0;
        $limit = intval( $params['limit'] );
        if ( $limit > 1 && !$params['intro'] ) {
            $limit = 1;
            $this->addWarning( [ 'apiwarn-textextracts-limit', $limit ] );
        }
        if ( isset( $params['continue'] ) ) {
            $continue = intval( $params['continue'] );
            $this->dieContinueUsageIf( $continue < 0 || $continue > count( $titles ) );
            $titles = array_slice( $titles, $continue, null, true );
        }
        $count = 0;
        $titleInFileNamespace = false;
        foreach ( $titles as $id => $t ) {
            if ( ++$count > $limit ) {
                $this->setContinueEnumParameter( 'continue', $continue + $count - 1 );
                break;
            }
 
            if ( $t->inNamespace( NS_FILE ) ) {
                $text = '';
                $titleInFileNamespace = true;
            } else {
                $params = $this->params;
                $text = $this->getExtract( $t );
                $text = $this->truncate( $text );
                if ( $params['plaintext'] ) {
                    $text = $this->doSections( $text );
                } else {
                    if ( $params['sentences'] ) {
                        $this->addWarning( $this->msg( 'apiwarn-textextracts-sentences-and-html', self::PREFIX ) );
                    }
                    $this->addWarning( 'apiwarn-textextracts-malformed-html' );
                }
            }
 
            if ( $isXml ) {
                $fit = $result->addValue( [ 'query', 'pages', $id ], 'extract', [ '*' => $text ] );
            } else {
                $fit = $result->addValue( [ 'query', 'pages', $id ], 'extract', $text );
            }
            if ( !$fit ) {
                $this->setContinueEnumParameter( 'continue', $continue + $count - 1 );
                break;
            }
        }
        if ( $titleInFileNamespace ) {
            $this->addWarning( 'apiwarn-textextracts-title-in-file-namespace' );
        }
    }
 
    public function getCacheMode( $params ) {
        return 'public';
    }
 
    private function getExtract( Title $title ) {
        $contentModel = $title->getContentModel();
        if ( !in_array( $contentModel, $this->supportedContentModels, true ) ) {
            $this->addWarning( [
                'apiwarn-textextracts-unsupportedmodel',
                wfEscapeWikiText( $title->getPrefixedText() ),
                $contentModel
            ] );
            return '';
        }
 
        $page = WikiPage::factory( $title );
 
        $introOnly = $this->params['intro'];
        $text = $this->getFromCache( $page, $introOnly );
        // if we need just first section, try retrieving full page and getting first section out of it
        if ( $text === false && $introOnly ) {
            $text = $this->getFromCache( $page, false );
            if ( $text !== false ) {
                $text = $this->getFirstSection( $text, $this->params['plaintext'] );
            }
        }
        if ( $text === false ) {
            $text = $this->parse( $page );
            $text = $this->convertText( $text );
            $this->setCache( $page, $text );
        }
        return $text;
    }
 
    private function cacheKey( BagOStuff $cache, WikiPage $page, $introOnly ) {
        return $cache->makeKey( 'textextracts', self::CACHE_VERSION,
            $page->getId(), $page->getTouched(),
            $page->getTitle()->getPageLanguage()->getPreferredVariant(),
            $this->params['plaintext'], $introOnly
        );
    }
 
    private function getFromCache( WikiPage $page, $introOnly ) {
        global $wgMemc;
 
        $key = $this->cacheKey( $wgMemc, $page, $introOnly );
        return $wgMemc->get( $key );
    }
 
    private function setCache( WikiPage $page, $text ) {
        global $wgMemc;
 
        $key = $this->cacheKey( $wgMemc, $page, $this->params['intro'] );
        $wgMemc->set( $key, $text, $this->getConfig()->get( 'ParserCacheExpireTime' ) );
    }
 
    private function getFirstSection( $text, $plainText ) {
        if ( $plainText ) {
            $regexp = '/^(.*?)(?=' . ExtractFormatter::SECTION_MARKER_START . ')/s';
        } else {
            $regexp = '/^(.*?)(?=<h[1-6]\b)/s';
        }
        if ( preg_match( $regexp, $text, $matches ) ) {
            $text = $matches[0];
        }
        return $text;
    }
 
    private function parse( WikiPage $page ) {
        $apiException = null;
        $parserOptions = new ParserOptions( new User() );
 
        // first try finding full page in parser cache
        if ( $page->shouldCheckParserCache( $parserOptions, 0 ) ) {
            $pout = MediaWikiServices::getInstance()->getParserCache()->get( $page, $parserOptions );
            if ( $pout ) {
                $text = $pout->getText( [ 'unwrap' => true ] );
                if ( $this->params['intro'] ) {
                    $text = $this->getFirstSection( $text, false );
                }
                return $text;
            }
        }
        $request = [
            'action' => 'parse',
            'page' => $page->getTitle()->getPrefixedText(),
            'prop' => 'text',
            // Invokes special handling when using partial wikitext (T168743)
            'sectionpreview' => 1,
            'wrapoutputclass' => '',
        ];
        if ( $this->params['intro'] ) {
            $request['section'] = 0;
        }
        // in case of cache miss, render just the needed section
        $api = new ApiMain( new FauxRequest( $request ) );
        try {
            $api->execute();
            $data = $api->getResult()->getResultData( null, [
                'BC' => [],
                'Types' => [],
            ] );
        } catch ( ApiUsageException $e ) {
            $apiException = $e->__toString();
            if ( $e->getStatusValue()->hasMessage( 'apierror-nosuchsection' ) ) {
                // Looks like we tried to get the intro to a page without
                // sections!  Lets just grab what we can get.
                unset( $request['section'] );
                $api = new ApiMain( new FauxRequest( $request ) );
                $api->execute();
                $data = $api->getResult()->getResultData( null, [
                    'BC' => [],
                    'Types' => [],
                ] );
            } else {
                // Some other unexpected error - lets just report it to the user
                // on the off chance that is the right thing.
                throw $e;
            }
        }
        if ( !array_key_exists( 'parse', $data ) ) {
            LoggerFactory::getInstance( 'textextracts' )->warning(
                'API Parse request failed while generating text extract', [
                    'title' => $page->getTitle()->getFullText(),
                    'url' => $this->getRequest()->getFullRequestURL(),
                    'exception' => $apiException,
                    'request' => $request
            ] );
            return null;
        }
 
        return $data['parse']['text']['*'];
    }
 
    public static function factory( $query, $name ) {
        $config = MediaWikiServices::getInstance()->getConfigFactory()->makeConfig( 'textextracts' );
        return new self( $query, $name, $config );
    }
 
    private function convertText( $text ) {
        $fmt = new ExtractFormatter( $text, $this->params['plaintext'] );
        $fmt->remove( $this->config->get( 'ExtractsRemoveClasses' ) );
        $text = $fmt->getText();
        return $text;
    }
 
    private function truncate( $text ) {
        if ( !$this->params['plaintext'] && MWTidy::isEnabled() ) {
            $truncator = new TextTruncator( MWTidy::singleton() );
        } else {
            $truncator = new TextTruncator();
        }
 
        if ( $this->params['chars'] ) {
            $text = $truncator->getFirstChars( $text, $this->params['chars'] ) .
                $this->msg( 'ellipsis' )->text();
        } elseif ( $this->params['sentences'] ) {
            $text = $truncator->getFirstSentences( $text, $this->params['sentences'] );
        }
        return $text;
    }
 
    private function doSections( $text ) {
        $pattern = '/' .
            ExtractFormatter::SECTION_MARKER_START . '(\d)' .
            ExtractFormatter::SECTION_MARKER_END . '(.*)/';
 
        switch ( $this->params['sectionformat'] ) {
            case 'raw':
                return $text;
 
            case 'wiki':
                return preg_replace_callback( $pattern, function ( $matches ) {
                    $bars = str_repeat( '=', $matches[1] );
                    return "\n$bars " . trim( $matches[2] ) . " $bars";
                }, $text );
 
            case 'plain':
                return preg_replace_callback( $pattern, function ( $matches ) {
                    return "\n" . trim( $matches[2] );
                }, $text );
 
            default:
                throw new \LogicException( 'Invalid sectionformat' );
        }
    }
 
    public function getAllowedParams() {
        return [
            'chars' => [
                ApiBase::PARAM_TYPE => 'integer',
                ApiBase::PARAM_MIN => 1,
                ApiBase::PARAM_MAX => 1200,
            ],
            'sentences' => [
                ApiBase::PARAM_TYPE => 'integer',
                ApiBase::PARAM_MIN => 1,
                ApiBase::PARAM_MAX => 10,
            ],
            'limit' => [
                ApiBase::PARAM_DFLT => 20,
                ApiBase::PARAM_TYPE => 'limit',
                ApiBase::PARAM_MIN => 1,
                ApiBase::PARAM_MAX => 20,
                ApiBase::PARAM_MAX2 => 20,
            ],
            'intro' => false,
            'plaintext' => false,
            'sectionformat' => [
                ApiBase::PARAM_TYPE => [ 'plain', 'wiki', 'raw' ],
                ApiBase::PARAM_DFLT => 'wiki',
            ],
            'continue' => [
                ApiBase::PARAM_TYPE => 'integer',
                ApiBase::PARAM_HELP_MSG => 'api-help-param-continue',
            ],
        ];
    }
 
    protected function getExamplesMessages() {
        return [
            'action=query&prop=extracts&exchars=175&titles=Therion'
                => 'apihelp-query+extracts-example-1',
        ];
    }
 
    public function getHelpUrls() {
        return 'https://www.mediawiki.org/wiki/Special:MyLanguage/Extension:TextExtracts#API';
    }
}