includes/filerepo/ForeignAPIRepo.php

   1 <?php
   2 /**
   3  * Foreign repository accessible through api.php requests.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @ingroup FileRepo
  22  */
  23
  24 use MediaWiki\Logger\LoggerFactory;
  25
  26 /**
  27  * A foreign repository with a remote MediaWiki with an API thingy
  28  *
  29  * Example config:
  30  *
  31  * $wgForeignFileRepos[] = array(
  32  *   'class'                  => 'ForeignAPIRepo',
  33  *   'name'                   => 'shared',
  34  *   'apibase'                => 'https://en.wikipedia.org/w/api.php',
  35  *   'fetchDescription'       => true, // Optional
  36  *   'descriptionCacheExpiry' => 3600,
  37  * );
  38  *
  39  * @ingroup FileRepo
  40  */
  41 class ForeignAPIRepo extends FileRepo {
  42         /* This version string is used in the user agent for requests and will help
  43          * server maintainers in identify ForeignAPI usage.
  44          * Update the version every time you make breaking or significant changes. */
  45         const VERSION = "2.1";
  46
  47         /**
  48          * List of iiprop values for the thumbnail fetch queries.
  49          * @since 1.23
  50          */
  51         protected static $imageInfoProps = array(
  52                 'url',
  53                 'timestamp',
  54         );
  55
  56         protected $fileFactory = array( 'ForeignAPIFile', 'newFromTitle' );
  57         /** @var int Check back with Commons after this expiry */
  58         protected $apiThumbCacheExpiry = 86400; // 1 day (24*3600)
  59
  60         /** @var int Redownload thumbnail files after this expiry */
  61         protected $fileCacheExpiry = 2592000; // 1 month (30*24*3600)
  62
  63         /** @var array */
  64         protected $mFileExists = array();
  65
  66         /** @var array */
  67         private $mQueryCache = array();
  68
  69         /**
  70          * @param array|null $info
  71          */
  72         function __construct( $info ) {
  73                 global $wgLocalFileRepo;
  74                 parent::__construct( $info );
  75
  76                 // https://commons.wikimedia.org/w/api.php
  77                 $this->mApiBase = isset( $info['apibase'] ) ? $info['apibase'] : null;
  78
  79                 if ( isset( $info['apiThumbCacheExpiry'] ) ) {
  80                         $this->apiThumbCacheExpiry = $info['apiThumbCacheExpiry'];
  81                 }
  82                 if ( isset( $info['fileCacheExpiry'] ) ) {
  83                         $this->fileCacheExpiry = $info['fileCacheExpiry'];
  84                 }
  85                 if ( !$this->scriptDirUrl ) {
  86                         // hack for description fetches
  87                         $this->scriptDirUrl = dirname( $this->mApiBase );
  88                 }
  89                 // If we can cache thumbs we can guess sane defaults for these
  90                 if ( $this->canCacheThumbs() && !$this->url ) {
  91                         $this->url = $wgLocalFileRepo['url'];
  92                 }
  93                 if ( $this->canCacheThumbs() && !$this->thumbUrl ) {
  94                         $this->thumbUrl = $this->url . '/thumb';
  95                 }
  96         }
  97
  98         /**
  99          * @return string
 100          * @since 1.22
 101          */
 102         function getApiUrl() {
 103                 return $this->mApiBase;
 104         }
 105
 106         /**
 107          * Per docs in FileRepo, this needs to return false if we don't support versioned
 108          * files. Well, we don't.
 109          *
 110          * @param Title $title
 111          * @param string|bool $time
 112          * @return File
 113          */
 114         function newFile( $title, $time = false ) {
 115                 if ( $time ) {
 116                         return false;
 117                 }
 118
 119                 return parent::newFile( $title, $time );
 120         }
 121
 122         /**
 123          * @param array $files
 124          * @return array
 125          */
 126         function fileExistsBatch( array $files ) {
 127                 $results = array();
 128                 foreach ( $files as $k => $f ) {
 129                         if ( isset( $this->mFileExists[$f] ) ) {
 130                                 $results[$k] = $this->mFileExists[$f];
 131                                 unset( $files[$k] );
 132                         } elseif ( self::isVirtualUrl( $f ) ) {
 133                                 # @todo FIXME: We need to be able to handle virtual
 134                                 # URLs better, at least when we know they refer to the
 135                                 # same repo.
 136                                 $results[$k] = false;
 137                                 unset( $files[$k] );
 138                         } elseif ( FileBackend::isStoragePath( $f ) ) {
 139                                 $results[$k] = false;
 140                                 unset( $files[$k] );
 141                                 wfWarn( "Got mwstore:// path '$f'." );
 142                         }
 143                 }
 144
 145                 $data = $this->fetchImageQuery( array(
 146                         'titles' => implode( $files, '|' ),
 147                         'prop' => 'imageinfo' )
 148                 );
 149
 150                 if ( isset( $data['query']['pages'] ) ) {
 151                         # First, get results from the query. Note we only care whether the image exists,
 152                         # not whether it has a description page.
 153                         foreach ( $data['query']['pages'] as $p ) {
 154                                 $this->mFileExists[$p['title']] = ( $p['imagerepository'] !== '' );
 155                         }
 156                         # Second, copy the results to any redirects that were queried
 157                         if ( isset( $data['query']['redirects'] ) ) {
 158                                 foreach ( $data['query']['redirects'] as $r ) {
 159                                         $this->mFileExists[$r['from']] = $this->mFileExists[$r['to']];
 160                                 }
 161                         }
 162                         # Third, copy the results to any non-normalized titles that were queried
 163                         if ( isset( $data['query']['normalized'] ) ) {
 164                                 foreach ( $data['query']['normalized'] as $n ) {
 165                                         $this->mFileExists[$n['from']] = $this->mFileExists[$n['to']];
 166                                 }
 167                         }
 168                         # Finally, copy the results to the output
 169                         foreach ( $files as $key => $file ) {
 170                                 $results[$key] = $this->mFileExists[$file];
 171                         }
 172                 }
 173
 174                 return $results;
 175         }
 176
 177         /**
 178          * @param string $virtualUrl
 179          * @return bool
 180          */
 181         function getFileProps( $virtualUrl ) {
 182                 return false;
 183         }
 184
 185         /**
 186          * @param array $query
 187          * @return string
 188          */
 189         function fetchImageQuery( $query ) {
 190                 global $wgLanguageCode;
 191
 192                 $query = array_merge( $query,
 193                         array(
 194                                 'format' => 'json',
 195                                 'action' => 'query',
 196                                 'redirects' => 'true'
 197                         ) );
 198
 199                 if ( !isset( $query['uselang'] ) ) { // uselang is unset or null
 200                         $query['uselang'] = $wgLanguageCode;
 201                 }
 202
 203                 $data = $this->httpGetCached( 'Metadata', $query );
 204
 205                 if ( $data ) {
 206                         return FormatJson::decode( $data, true );
 207                 } else {
 208                         return null;
 209                 }
 210         }
 211
 212         /**
 213          * @param array $data
 214          * @return bool|array
 215          */
 216         function getImageInfo( $data ) {
 217                 if ( $data && isset( $data['query']['pages'] ) ) {
 218                         foreach ( $data['query']['pages'] as $info ) {
 219                                 if ( isset( $info['imageinfo'][0] ) ) {
 220                                         $return = $info['imageinfo'][0];
 221                                         if ( isset( $info['pageid'] ) ) {
 222                                                 $return['pageid'] = $info['pageid'];
 223                                         }
 224                                         return $return;
 225                                 }
 226                         }
 227                 }
 228
 229                 return false;
 230         }
 231
 232         /**
 233          * @param string $hash
 234          * @return array
 235          */
 236         function findBySha1( $hash ) {
 237                 $results = $this->fetchImageQuery( array(
 238                         'aisha1base36' => $hash,
 239                         'aiprop' => ForeignAPIFile::getProps(),
 240                         'list' => 'allimages',
 241                 ) );
 242                 $ret = array();
 243                 if ( isset( $results['query']['allimages'] ) ) {
 244                         foreach ( $results['query']['allimages'] as $img ) {
 245                                 // 1.14 was broken, doesn't return name attribute
 246                                 if ( !isset( $img['name'] ) ) {
 247                                         continue;
 248                                 }
 249                                 $ret[] = new ForeignAPIFile( Title::makeTitle( NS_FILE, $img['name'] ), $this, $img );
 250                         }
 251                 }
 252
 253                 return $ret;
 254         }
 255
 256         /**
 257          * @param string $name
 258          * @param int $width
 259          * @param int $height
 260          * @param array $result Out parameter that will be changed by the function.
 261          * @param string $otherParams
 262          *
 263          * @return bool
 264          */
 265         function getThumbUrl( $name, $width = -1, $height = -1, &$result = null, $otherParams = '' ) {
 266                 $data = $this->fetchImageQuery( array(
 267                         'titles' => 'File:' . $name,
 268                         'iiprop' => self::getIIProps(),
 269                         'iiurlwidth' => $width,
 270                         'iiurlheight' => $height,
 271                         'iiurlparam' => $otherParams,
 272                         'prop' => 'imageinfo' ) );
 273                 $info = $this->getImageInfo( $data );
 274
 275                 if ( $data && $info && isset( $info['thumburl'] ) ) {
 276                         wfDebug( __METHOD__ . " got remote thumb " . $info['thumburl'] . "\n" );
 277                         $result = $info;
 278
 279                         return $info['thumburl'];
 280                 } else {
 281                         return false;
 282                 }
 283         }
 284
 285         /**
 286          * @param string $name
 287          * @param int $width
 288          * @param int $height
 289          * @param string $otherParams
 290          * @param string $lang Language code for language of error
 291          * @return bool|MediaTransformError
 292          * @since 1.22
 293          */
 294         function getThumbError( $name, $width = -1, $height = -1, $otherParams = '', $lang = null ) {
 295                 $data = $this->fetchImageQuery( array(
 296                         'titles' => 'File:' . $name,
 297                         'iiprop' => self::getIIProps(),
 298                         'iiurlwidth' => $width,
 299                         'iiurlheight' => $height,
 300                         'iiurlparam' => $otherParams,
 301                         'prop' => 'imageinfo',
 302                         'uselang' => $lang,
 303                 ) );
 304                 $info = $this->getImageInfo( $data );
 305
 306                 if ( $data && $info && isset( $info['thumberror'] ) ) {
 307                         wfDebug( __METHOD__ . " got remote thumb error " . $info['thumberror'] . "\n" );
 308
 309                         return new MediaTransformError(
 310                                 'thumbnail_error_remote',
 311                                 $width,
 312                                 $height,
 313                                 $this->getDisplayName(),
 314                                 $info['thumberror'] // already parsed message from foreign repo
 315                         );
 316                 } else {
 317                         return false;
 318                 }
 319         }
 320
 321         /**
 322          * Return the imageurl from cache if possible
 323          *
 324          * If the url has been requested today, get it from cache
 325          * Otherwise retrieve remote thumb url, check for local file.
 326          *
 327          * @param string $name Is a dbkey form of a title
 328          * @param int $width
 329          * @param int $height
 330          * @param string $params Other rendering parameters (page number, etc)
 331          *   from handler's makeParamString.
 332          * @return bool|string
 333          */
 334         function getThumbUrlFromCache( $name, $width, $height, $params = "" ) {
 335                 $cache = ObjectCache::getMainWANInstance();
 336                 // We can't check the local cache using FileRepo functions because
 337                 // we override fileExistsBatch(). We have to use the FileBackend directly.
 338                 $backend = $this->getBackend(); // convenience
 339
 340                 if ( !$this->canCacheThumbs() ) {
 341                         $result = null; // can't pass "null" by reference, but it's ok as default value
 342                         return $this->getThumbUrl( $name, $width, $height, $result, $params );
 343                 }
 344                 $key = $this->getLocalCacheKey( 'ForeignAPIRepo', 'ThumbUrl', $name );
 345                 $sizekey = "$width:$height:$params";
 346
 347                 /* Get the array of urls that we already know */
 348                 $knownThumbUrls = $cache->get( $key );
 349                 if ( !$knownThumbUrls ) {
 350                         /* No knownThumbUrls for this file */
 351                         $knownThumbUrls = array();
 352                 } else {
 353                         if ( isset( $knownThumbUrls[$sizekey] ) ) {
 354                                 wfDebug( __METHOD__ . ': Got thumburl from local cache: ' .
 355                                         "{$knownThumbUrls[$sizekey]} \n" );
 356
 357                                 return $knownThumbUrls[$sizekey];
 358                         }
 359                         /* This size is not yet known */
 360                 }
 361
 362                 $metadata = null;
 363                 $foreignUrl = $this->getThumbUrl( $name, $width, $height, $metadata, $params );
 364
 365                 if ( !$foreignUrl ) {
 366                         wfDebug( __METHOD__ . " Could not find thumburl\n" );
 367
 368                         return false;
 369                 }
 370
 371                 // We need the same filename as the remote one :)
 372                 $fileName = rawurldecode( pathinfo( $foreignUrl, PATHINFO_BASENAME ) );
 373                 if ( !$this->validateFilename( $fileName ) ) {
 374                         wfDebug( __METHOD__ . " The deduced filename $fileName is not safe\n" );
 375
 376                         return false;
 377                 }
 378                 $localPath = $this->getZonePath( 'thumb' ) . "/" . $this->getHashPath( $name ) . $name;
 379                 $localFilename = $localPath . "/" . $fileName;
 380                 $localUrl = $this->getZoneUrl( 'thumb' ) . "/" . $this->getHashPath( $name ) .
 381                         rawurlencode( $name ) . "/" . rawurlencode( $fileName );
 382
 383                 if ( $backend->fileExists( array( 'src' => $localFilename ) )
 384                         && isset( $metadata['timestamp'] )
 385                 ) {
 386                         wfDebug( __METHOD__ . " Thumbnail was already downloaded before\n" );
 387                         $modified = $backend->getFileTimestamp( array( 'src' => $localFilename ) );
 388                         $remoteModified = strtotime( $metadata['timestamp'] );
 389                         $current = time();
 390                         $diff = abs( $modified - $current );
 391                         if ( $remoteModified < $modified && $diff < $this->fileCacheExpiry ) {
 392                                 /* Use our current and already downloaded thumbnail */
 393                                 $knownThumbUrls[$sizekey] = $localUrl;
 394                                 $cache->set( $key, $knownThumbUrls, $this->apiThumbCacheExpiry );
 395
 396                                 return $localUrl;
 397                         }
 398                         /* There is a new Commons file, or existing thumbnail older than a month */
 399                 }
 400                 $thumb = self::httpGet( $foreignUrl );
 401                 if ( !$thumb ) {
 402                         wfDebug( __METHOD__ . " Could not download thumb\n" );
 403
 404                         return false;
 405                 }
 406
 407                 # @todo FIXME: Delete old thumbs that aren't being used. Maintenance script?
 408                 $backend->prepare( array( 'dir' => dirname( $localFilename ) ) );
 409                 $params = array( 'dst' => $localFilename, 'content' => $thumb );
 410                 if ( !$backend->quickCreate( $params )->isOK() ) {
 411                         wfDebug( __METHOD__ . " could not write to thumb path '$localFilename'\n" );
 412
 413                         return $foreignUrl;
 414                 }
 415                 $knownThumbUrls[$sizekey] = $localUrl;
 416                 $cache->set( $key, $knownThumbUrls, $this->apiThumbCacheExpiry );
 417                 wfDebug( __METHOD__ . " got local thumb $localUrl, saving to cache \n" );
 418
 419                 return $localUrl;
 420         }
 421
 422         /**
 423          * @see FileRepo::getZoneUrl()
 424          * @param string $zone
 425          * @param string|null $ext Optional file extension
 426          * @return string
 427          */
 428         function getZoneUrl( $zone, $ext = null ) {
 429                 switch ( $zone ) {
 430                         case 'public':
 431                                 return $this->url;
 432                         case 'thumb':
 433                                 return $this->thumbUrl;
 434                         default:
 435                                 return parent::getZoneUrl( $zone, $ext );
 436                 }
 437         }
 438
 439         /**
 440          * Get the local directory corresponding to one of the basic zones
 441          * @param string $zone
 442          * @return bool|null|string
 443          */
 444         function getZonePath( $zone ) {
 445                 $supported = array( 'public', 'thumb' );
 446                 if ( in_array( $zone, $supported ) ) {
 447                         return parent::getZonePath( $zone );
 448                 }
 449
 450                 return false;
 451         }
 452
 453         /**
 454          * Are we locally caching the thumbnails?
 455          * @return bool
 456          */
 457         public function canCacheThumbs() {
 458                 return ( $this->apiThumbCacheExpiry > 0 );
 459         }
 460
 461         /**
 462          * The user agent the ForeignAPIRepo will use.
 463          * @return string
 464          */
 465         public static function getUserAgent() {
 466                 return Http::userAgent() . " ForeignAPIRepo/" . self::VERSION;
 467         }
 468
 469         /**
 470          * Get information about the repo - overrides/extends the parent
 471          * class's information.
 472          * @return array
 473          * @since 1.22
 474          */
 475         function getInfo() {
 476                 $info = parent::getInfo();
 477                 $info['apiurl'] = $this->getApiUrl();
 478
 479                 $query = array(
 480                         'format' => 'json',
 481                         'action' => 'query',
 482                         'meta' => 'siteinfo',
 483                         'siprop' => 'general',
 484                 );
 485
 486                 $data = $this->httpGetCached( 'SiteInfo', $query, 7200 );
 487
 488                 if ( $data ) {
 489                         $siteInfo = FormatJson::decode( $data, true );
 490                         $general = $siteInfo['query']['general'];
 491
 492                         $info['articlepath'] = $general['articlepath'];
 493                         $info['server'] = $general['server'];
 494
 495                         if ( isset( $general['favicon'] ) ) {
 496                                 $info['favicon'] = $general['favicon'];
 497                         }
 498                 }
 499
 500                 return $info;
 501         }
 502
 503         /**
 504          * Like a Http:get request, but with custom User-Agent.
 505          * @see Http::get
 506          * @param string $url
 507          * @param string $timeout
 508          * @param array $options
 509          * @return bool|string
 510          */
 511         public static function httpGet( $url, $timeout = 'default', $options = array() ) {
 512                 $options['timeout'] = $timeout;
 513                 /* Http::get */
 514                 $url = wfExpandUrl( $url, PROTO_HTTP );
 515                 wfDebug( "ForeignAPIRepo: HTTP GET: $url\n" );
 516                 $options['method'] = "GET";
 517
 518                 if ( !isset( $options['timeout'] ) ) {
 519                         $options['timeout'] = 'default';
 520                 }
 521
 522                 $req = MWHttpRequest::factory( $url, $options, __METHOD__ );
 523                 $req->setUserAgent( ForeignAPIRepo::getUserAgent() );
 524                 $status = $req->execute();
 525
 526                 if ( $status->isOK() ) {
 527                         return $req->getContent();
 528                 } else {
 529                         $logger = LoggerFactory::getInstance( 'http' );
 530                         $logger->warning( $status->getWikiText(), array( 'caller' => 'ForeignAPIRepo::httpGet' ) );
 531                         return false;
 532                 }
 533         }
 534
 535         /**
 536          * @return string
 537          * @since 1.23
 538          */
 539         protected static function getIIProps() {
 540                 return join( '|', self::$imageInfoProps );
 541         }
 542
 543         /**
 544          * HTTP GET request to a mediawiki API (with caching)
 545          * @param string $target Used in cache key creation, mostly
 546          * @param array $query The query parameters for the API request
 547          * @param int $cacheTTL Time to live for the memcached caching
 548          * @return null
 549          */
 550         public function httpGetCached( $target, $query, $cacheTTL = 3600 ) {
 551                 if ( $this->mApiBase ) {
 552                         $url = wfAppendQuery( $this->mApiBase, $query );
 553                 } else {
 554                         $url = $this->makeUrl( $query, 'api' );
 555                 }
 556
 557                 if ( !isset( $this->mQueryCache[$url] ) ) {
 558                         $data = ObjectCache::getMainWANInstance()->getWithSetCallback(
 559                                 $this->getLocalCacheKey( get_class( $this ), $target, md5( $url ) ),
 560                                 $cacheTTL,
 561                                 function () use ( $url ) {
 562                                         return ForeignAPIRepo::httpGet( $url );
 563                                 }
 564                         );
 565
 566                         if ( !$data ) {
 567                                 return null;
 568                         }
 569
 570                         if ( count( $this->mQueryCache ) > 100 ) {
 571                                 // Keep the cache from growing infinitely
 572                                 $this->mQueryCache = array();
 573                         }
 574
 575                         $this->mQueryCache[$url] = $data;
 576                 }
 577
 578                 return $this->mQueryCache[$url];
 579         }
 580
 581         /**
 582          * @param callable $callback
 583          * @throws MWException
 584          */
 585         function enumFiles( $callback ) {
 586                 throw new MWException( 'enumFiles is not supported by ' . get_class( $this ) );
 587         }
 588
 589         /**
 590          * @throws MWException
 591          */
 592         protected function assertWritableRepo() {
 593                 throw new MWException( get_class( $this ) . ': write operations are not supported.' );
 594         }
 595 }