includes/api/ApiOpenSearch.php

   1 <?php
   2 /**
   3  * Created on Oct 13, 2006
   4  *
   5  * Copyright © 2006 Yuri Astrakhan "<Firstname><Lastname>@gmail.com"
   6  * Copyright © 2008 Brion Vibber <brion@wikimedia.org>
   7  * Copyright © 2014 Brad Jorsch <bjorsch@wikimedia.org>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License along
  20  * with this program; if not, write to the Free Software Foundation, Inc.,
  21  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  22  * http://www.gnu.org/copyleft/gpl.html
  23  *
  24  * @file
  25  */
  26
  27 use MediaWiki\MediaWikiServices;
  28 use Wikimedia\Rdbms\Database;
  29
  30 /**
  31  * @ingroup API
  32  */
  33 class ApiOpenSearch extends ApiBase {
  34         use SearchApi;
  35
  36         private $format = null;
  37         private $fm = null;
  38
  39         /** @var array list of api allowed params */
  40         private $allowedParams = null;
  41
  42         /**
  43          * Get the output format
  44          *
  45          * @return string
  46          */
  47         protected function getFormat() {
  48                 if ( $this->format === null ) {
  49                         $params = $this->extractRequestParams();
  50                         $format = $params['format'];
  51
  52                         $allowedParams = $this->getAllowedParams();
  53                         if ( !in_array( $format, $allowedParams['format'][ApiBase::PARAM_TYPE] ) ) {
  54                                 $format = $allowedParams['format'][ApiBase::PARAM_DFLT];
  55                         }
  56
  57                         if ( substr( $format, -2 ) === 'fm' ) {
  58                                 $this->format = substr( $format, 0, -2 );
  59                                 $this->fm = 'fm';
  60                         } else {
  61                                 $this->format = $format;
  62                                 $this->fm = '';
  63                         }
  64                 }
  65                 return $this->format;
  66         }
  67
  68         public function getCustomPrinter() {
  69                 switch ( $this->getFormat() ) {
  70                         case 'json':
  71                                 return new ApiOpenSearchFormatJson(
  72                                         $this->getMain(), $this->fm, $this->getParameter( 'warningsaserror' )
  73                                 );
  74
  75                         case 'xml':
  76                                 $printer = $this->getMain()->createPrinterByName( 'xml' . $this->fm );
  77                                 $printer->setRootElement( 'SearchSuggestion' );
  78                                 return $printer;
  79
  80                         default:
  81                                 ApiBase::dieDebug( __METHOD__, "Unsupported format '{$this->getFormat()}'" );
  82                 }
  83         }
  84
  85         public function execute() {
  86                 $params = $this->extractRequestParams();
  87                 $search = $params['search'];
  88                 $suggest = $params['suggest'];
  89                 $results = [];
  90                 if ( !$suggest || $this->getConfig()->get( 'EnableOpenSearchSuggest' ) ) {
  91                         // Open search results may be stored for a very long time
  92                         $this->getMain()->setCacheMaxAge( $this->getConfig()->get( 'SearchSuggestCacheExpiry' ) );
  93                         $this->getMain()->setCacheMode( 'public' );
  94                         $results = $this->search( $search, $params );
  95
  96                         // Allow hooks to populate extracts and images
  97                         Hooks::run( 'ApiOpenSearchSuggest', [ &$results ] );
  98
  99                         // Trim extracts, if necessary
 100                         $length = $this->getConfig()->get( 'OpenSearchDescriptionLength' );
 101                         foreach ( $results as &$r ) {
 102                                 if ( is_string( $r['extract'] ) && !$r['extract trimmed'] ) {
 103                                         $r['extract'] = self::trimExtract( $r['extract'], $length );
 104                                 }
 105                         }
 106                 }
 107
 108                 // Populate result object
 109                 $this->populateResult( $search, $results );
 110         }
 111
 112         /**
 113          * Perform the search
 114          * @param string $search the search query
 115          * @param array $params api request params
 116          * @return array search results. Keys are integers.
 117          */
 118         private function search( $search, array $params ) {
 119                 $searchEngine = $this->buildSearchEngine( $params );
 120                 $titles = $searchEngine->extractTitles( $searchEngine->completionSearchWithVariants( $search ) );
 121                 $results = [];
 122
 123                 if ( !$titles ) {
 124                         return $results;
 125                 }
 126
 127                 // Special pages need unique integer ids in the return list, so we just
 128                 // assign them negative numbers because those won't clash with the
 129                 // always positive articleIds that non-special pages get.
 130                 $nextSpecialPageId = -1;
 131
 132                 if ( $params['redirects'] === null ) {
 133                         // Backwards compatibility, don't resolve for JSON.
 134                         $resolveRedir = $this->getFormat() !== 'json';
 135                 } else {
 136                         $resolveRedir = $params['redirects'] === 'resolve';
 137                 }
 138
 139                 if ( $resolveRedir ) {
 140                         // Query for redirects
 141                         $redirects = [];
 142                         $lb = new LinkBatch( $titles );
 143                         if ( !$lb->isEmpty() ) {
 144                                 $db = $this->getDB();
 145                                 $res = $db->select(
 146                                         [ 'page', 'redirect' ],
 147                                         [ 'page_namespace', 'page_title', 'rd_namespace', 'rd_title' ],
 148                                         [
 149                                                 'rd_from = page_id',
 150                                                 'rd_interwiki IS NULL OR rd_interwiki = ' . $db->addQuotes( '' ),
 151                                                 $lb->constructSet( 'page', $db ),
 152                                         ],
 153                                         __METHOD__
 154                                 );
 155                                 foreach ( $res as $row ) {
 156                                         $redirects[$row->page_namespace][$row->page_title] =
 157                                                 [ $row->rd_namespace, $row->rd_title ];
 158                                 }
 159                         }
 160
 161                         // Bypass any redirects
 162                         $seen = [];
 163                         foreach ( $titles as $title ) {
 164                                 $ns = $title->getNamespace();
 165                                 $dbkey = $title->getDBkey();
 166                                 $from = null;
 167                                 if ( isset( $redirects[$ns][$dbkey] ) ) {
 168                                         list( $ns, $dbkey ) = $redirects[$ns][$dbkey];
 169                                         $from = $title;
 170                                         $title = Title::makeTitle( $ns, $dbkey );
 171                                 }
 172                                 if ( !isset( $seen[$ns][$dbkey] ) ) {
 173                                         $seen[$ns][$dbkey] = true;
 174                                         $resultId = $title->getArticleID();
 175                                         if ( $resultId === 0 ) {
 176                                                 $resultId = $nextSpecialPageId;
 177                                                 $nextSpecialPageId -= 1;
 178                                         }
 179                                         $results[$resultId] = [
 180                                                 'title' => $title,
 181                                                 'redirect from' => $from,
 182                                                 'extract' => false,
 183                                                 'extract trimmed' => false,
 184                                                 'image' => false,
 185                                                 'url' => wfExpandUrl( $title->getFullURL(), PROTO_CURRENT ),
 186                                         ];
 187                                 }
 188                         }
 189                 } else {
 190                         foreach ( $titles as $title ) {
 191                                 $resultId = $title->getArticleID();
 192                                 if ( $resultId === 0 ) {
 193                                         $resultId = $nextSpecialPageId;
 194                                         $nextSpecialPageId -= 1;
 195                                 }
 196                                 $results[$resultId] = [
 197                                         'title' => $title,
 198                                         'redirect from' => null,
 199                                         'extract' => false,
 200                                         'extract trimmed' => false,
 201                                         'image' => false,
 202                                         'url' => wfExpandUrl( $title->getFullURL(), PROTO_CURRENT ),
 203                                 ];
 204                         }
 205                 }
 206
 207                 return $results;
 208         }
 209
 210         /**
 211          * @param string $search
 212          * @param array &$results
 213          */
 214         protected function populateResult( $search, &$results ) {
 215                 $result = $this->getResult();
 216
 217                 switch ( $this->getFormat() ) {
 218                         case 'json':
 219                                 // http://www.opensearch.org/Specifications/OpenSearch/Extensions/Suggestions/1.1
 220                                 $result->addArrayType( null, 'array' );
 221                                 $result->addValue( null, 0, strval( $search ) );
 222                                 $terms = [];
 223                                 $descriptions = [];
 224                                 $urls = [];
 225                                 foreach ( $results as $r ) {
 226                                         $terms[] = $r['title']->getPrefixedText();
 227                                         $descriptions[] = strval( $r['extract'] );
 228                                         $urls[] = $r['url'];
 229                                 }
 230                                 $result->addValue( null, 1, $terms );
 231                                 $result->addValue( null, 2, $descriptions );
 232                                 $result->addValue( null, 3, $urls );
 233                                 break;
 234
 235                         case 'xml':
 236                                 // http://msdn.microsoft.com/en-us/library/cc891508%28v=vs.85%29.aspx
 237                                 $imageKeys = [
 238                                         'source' => true,
 239                                         'alt' => true,
 240                                         'width' => true,
 241                                         'height' => true,
 242                                         'align' => true,
 243                                 ];
 244                                 $items = [];
 245                                 foreach ( $results as $r ) {
 246                                         $item = [
 247                                                 'Text' => $r['title']->getPrefixedText(),
 248                                                 'Url' => $r['url'],
 249                                         ];
 250                                         if ( is_string( $r['extract'] ) && $r['extract'] !== '' ) {
 251                                                 $item['Description'] = $r['extract'];
 252                                         }
 253                                         if ( is_array( $r['image'] ) && isset( $r['image']['source'] ) ) {
 254                                                 $item['Image'] = array_intersect_key( $r['image'], $imageKeys );
 255                                         }
 256                                         ApiResult::setSubelementsList( $item, array_keys( $item ) );
 257                                         $items[] = $item;
 258                                 }
 259                                 ApiResult::setIndexedTagName( $items, 'Item' );
 260                                 $result->addValue( null, 'version', '2.0' );
 261                                 $result->addValue( null, 'xmlns', 'http://opensearch.org/searchsuggest2' );
 262                                 $result->addValue( null, 'Query', strval( $search ) );
 263                                 $result->addSubelementsList( null, 'Query' );
 264                                 $result->addValue( null, 'Section', $items );
 265                                 break;
 266
 267                         default:
 268                                 ApiBase::dieDebug( __METHOD__, "Unsupported format '{$this->getFormat()}'" );
 269                 }
 270         }
 271
 272         public function getAllowedParams() {
 273                 if ( $this->allowedParams !== null ) {
 274                         return $this->allowedParams;
 275                 }
 276                 $this->allowedParams = $this->buildCommonApiParams( false ) + [
 277                         'suggest' => false,
 278                         'redirects' => [
 279                                 ApiBase::PARAM_TYPE => [ 'return', 'resolve' ],
 280                         ],
 281                         'format' => [
 282                                 ApiBase::PARAM_DFLT => 'json',
 283                                 ApiBase::PARAM_TYPE => [ 'json', 'jsonfm', 'xml', 'xmlfm' ],
 284                         ],
 285                         'warningsaserror' => false,
 286                 ];
 287
 288                 // Use open search specific default limit
 289                 $this->allowedParams['limit'][ApiBase::PARAM_DFLT] = $this->getConfig()->get(
 290                         'OpenSearchDefaultLimit'
 291                 );
 292
 293                 return $this->allowedParams;
 294         }
 295
 296         public function getSearchProfileParams() {
 297                 return [
 298                         'profile' => [
 299                                 'profile-type' => SearchEngine::COMPLETION_PROFILE_TYPE,
 300                                 'help-message' => 'apihelp-query+prefixsearch-param-profile'
 301                         ],
 302                 ];
 303         }
 304
 305         protected function getExamplesMessages() {
 306                 return [
 307                         'action=opensearch&search=Te'
 308                                 => 'apihelp-opensearch-example-te',
 309                 ];
 310         }
 311
 312         public function getHelpUrls() {
 313                 return 'https://www.mediawiki.org/wiki/Special:MyLanguage/API:Opensearch';
 314         }
 315
 316         /**
 317          * Trim an extract to a sensible length.
 318          *
 319          * Adapted from Extension:OpenSearchXml, which adapted it from
 320          * Extension:ActiveAbstract.
 321          *
 322          * @param string $text
 323          * @param int $length Target length; actual result will continue to the end of a sentence.
 324          * @return string
 325          */
 326         public static function trimExtract( $text, $length ) {
 327                 static $regex = null;
 328
 329                 if ( $regex === null ) {
 330                         $endchars = [
 331                                 '([^\d])\.\s', '\!\s', '\?\s', // regular ASCII
 332                                 '。', // full-width ideographic full-stop
 333                                 '．', '！', '？', // double-width roman forms
 334                                 '｡', // half-width ideographic full stop
 335                         ];
 336                         $endgroup = implode( '|', $endchars );
 337                         $end = "(?:$endgroup)";
 338                         $sentence = ".{{$length},}?$end+";
 339                         $regex = "/^($sentence)/u";
 340                 }
 341
 342                 $matches = [];
 343                 if ( preg_match( $regex, $text, $matches ) ) {
 344                         return trim( $matches[1] );
 345                 } else {
 346                         // Just return the first line
 347                         return trim( explode( "\n", $text )[0] );
 348                 }
 349         }
 350
 351         /**
 352          * Fetch the template for a type.
 353          *
 354          * @param string $type MIME type
 355          * @return string
 356          * @throws MWException
 357          */
 358         public static function getOpenSearchTemplate( $type ) {
 359                 $config = MediaWikiServices::getInstance()->getSearchEngineConfig();
 360                 $template = $config->getConfig()->get( 'OpenSearchTemplate' );
 361
 362                 if ( $template && $type === 'application/x-suggestions+json' ) {
 363                         return $template;
 364                 }
 365
 366                 $ns = implode( '|', $config->defaultNamespaces() );
 367                 if ( !$ns ) {
 368                         $ns = '0';
 369                 }
 370
 371                 switch ( $type ) {
 372                         case 'application/x-suggestions+json':
 373                                 return $config->getConfig()->get( 'CanonicalServer' ) . wfScript( 'api' )
 374                                         . '?action=opensearch&search={searchTerms}&namespace=' . $ns;
 375
 376                         case 'application/x-suggestions+xml':
 377                                 return $config->getConfig()->get( 'CanonicalServer' ) . wfScript( 'api' )
 378                                         . '?action=opensearch&format=xml&search={searchTerms}&namespace=' . $ns;
 379
 380                         default:
 381                                 throw new MWException( __METHOD__ . ": Unknown type '$type'" );
 382                 }
 383         }
 384 }
 385
 386 class ApiOpenSearchFormatJson extends ApiFormatJson {
 387         private $warningsAsError = false;
 388
 389         public function __construct( ApiMain $main, $fm, $warningsAsError ) {
 390                 parent::__construct( $main, "json$fm" );
 391                 $this->warningsAsError = $warningsAsError;
 392         }
 393
 394         public function execute() {
 395                 $result = $this->getResult();
 396                 if ( !$result->getResultData( 'error' ) && !$result->getResultData( 'errors' ) ) {
 397                         // Ignore warnings or treat as errors, as requested
 398                         $warnings = $result->removeValue( 'warnings', null );
 399                         if ( $this->warningsAsError && $warnings ) {
 400                                 $this->dieWithError(
 401                                         'apierror-opensearch-json-warnings',
 402                                         'warnings',
 403                                         [ 'warnings' => $warnings ]
 404                                 );
 405                         }
 406
 407                         // Ignore any other unexpected keys (e.g. from $wgDebugToolbar)
 408                         $remove = array_keys( array_diff_key(
 409                                 $result->getResultData(),
 410                                 [ 0 => 'search', 1 => 'terms', 2 => 'descriptions', 3 => 'urls' ]
 411                         ) );
 412                         foreach ( $remove as $key ) {
 413                                 $result->removeValue( $key, null );
 414                         }
 415                 }
 416
 417                 parent::execute();
 418         }
 419 }