includes/filerepo/ForeignAPIRepo.php
<?php
/**
* 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
*/
use MediaWiki\Json\FormatJson;
use MediaWiki\Linker\LinkTarget;
use MediaWiki\Logger\LoggerFactory;
use MediaWiki\MainConfigNames;
use MediaWiki\MediaWikiServices;
use MediaWiki\Page\PageIdentity;
use MediaWiki\Title\Title;
use Wikimedia\FileBackend\FileBackend;
/**
* A foreign repository for a remote MediaWiki accessible through api.php requests.
*
* @par Example config:
* @code
* $wgForeignFileRepos[] = [
* 'class' => ForeignAPIRepo::class,
* 'name' => 'shared',
* 'apibase' => 'https://en.wikipedia.org/w/api.php',
* 'fetchDescription' => true, // Optional
* 'descriptionCacheExpiry' => 3600,
* ];
* @endcode
*
* @ingroup FileRepo
*/
class ForeignAPIRepo extends FileRepo implements IForeignRepoWithMWApi {
/* This version string is used in the user agent for requests and will help
* server maintainers in identify ForeignAPI usage.
* Update the version every time you make breaking or significant changes. */
private const VERSION = "2.1";
/**
* List of iiprop values for the thumbnail fetch queries.
*/
private const IMAGE_INFO_PROPS = [
'url',
'timestamp',
];
/** @var callable */
protected $fileFactory = [ ForeignAPIFile::class, 'newFromTitle' ];
/** @var int Check back with Commons after this expiry */
protected $apiThumbCacheExpiry = 24 * 3600; // 1 day
/** @var int Redownload thumbnail files after this expiry */
protected $fileCacheExpiry = 30 * 24 * 3600; // 1 month
/**
* @var int API metadata cache time.
* @since 1.38
*
* This is often the performance bottleneck for ForeignAPIRepo. For
* each file used, we must fetch file metadata for it and every high-DPI
* variant, in serial, during the parse. This is slow if a page has many
* files, with RTT of the handshake often being significant. The metadata
* rarely changes, but if a new version of the file was uploaded, it might
* be displayed incorrectly until its metadata entry falls out of cache.
*/
protected $apiMetadataExpiry = 4 * 3600; // 4 hours
/** @var array */
protected $mFileExists = [];
/** @var string */
private $mApiBase;
/**
* @param array|null $info
*/
public function __construct( $info ) {
$localFileRepo = MediaWikiServices::getInstance()->getMainConfig()
->get( MainConfigNames::LocalFileRepo );
parent::__construct( $info );
// https://commons.wikimedia.org/w/api.php
$this->mApiBase = $info['apibase'] ?? null;
if ( isset( $info['apiThumbCacheExpiry'] ) ) {
$this->apiThumbCacheExpiry = $info['apiThumbCacheExpiry'];
}
if ( isset( $info['fileCacheExpiry'] ) ) {
$this->fileCacheExpiry = $info['fileCacheExpiry'];
}
if ( isset( $info['apiMetadataExpiry'] ) ) {
$this->apiMetadataExpiry = $info['apiMetadataExpiry'];
}
if ( !$this->scriptDirUrl ) {
// hack for description fetches
$this->scriptDirUrl = dirname( $this->mApiBase );
}
// If we can cache thumbs we can guess sensible defaults for these
if ( $this->canCacheThumbs() && !$this->url ) {
$this->url = $localFileRepo['url'];
}
if ( $this->canCacheThumbs() && !$this->thumbUrl ) {
$this->thumbUrl = $this->url . '/thumb';
}
}
/**
* Per docs in FileRepo, this needs to return false if we don't support versioned
* files. Well, we don't.
*
* @param PageIdentity|LinkTarget|string $title
* @param string|false $time
* @return File|false
*/
public function newFile( $title, $time = false ) {
if ( $time ) {
return false;
}
return parent::newFile( $title, $time );
}
/**
* @param string[] $files
* @return array
*/
public function fileExistsBatch( array $files ) {
$results = [];
foreach ( $files as $k => $f ) {
if ( isset( $this->mFileExists[$f] ) ) {
$results[$k] = $this->mFileExists[$f];
unset( $files[$k] );
} elseif ( self::isVirtualUrl( $f ) ) {
# @todo FIXME: We need to be able to handle virtual
# URLs better, at least when we know they refer to the
# same repo.
$results[$k] = false;
unset( $files[$k] );
} elseif ( FileBackend::isStoragePath( $f ) ) {
$results[$k] = false;
unset( $files[$k] );
wfWarn( "Got mwstore:// path '$f'." );
}
}
$data = $this->fetchImageQuery( [
'titles' => implode( '|', $files ),
'prop' => 'imageinfo' ]
);
if ( isset( $data['query']['pages'] ) ) {
# First, get results from the query. Note we only care whether the image exists,
# not whether it has a description page.
foreach ( $data['query']['pages'] as $p ) {
$this->mFileExists[$p['title']] = ( $p['imagerepository'] !== '' );
}
# Second, copy the results to any redirects that were queried
if ( isset( $data['query']['redirects'] ) ) {
foreach ( $data['query']['redirects'] as $r ) {
$this->mFileExists[$r['from']] = $this->mFileExists[$r['to']];
}
}
# Third, copy the results to any non-normalized titles that were queried
if ( isset( $data['query']['normalized'] ) ) {
foreach ( $data['query']['normalized'] as $n ) {
$this->mFileExists[$n['from']] = $this->mFileExists[$n['to']];
}
}
# Finally, copy the results to the output
foreach ( $files as $key => $file ) {
$results[$key] = $this->mFileExists[$file];
}
}
return $results;
}
/**
* @param string $virtualUrl
* @return array
*/
public function getFileProps( $virtualUrl ) {
return [];
}
/**
* Make an API query in the foreign repo, caching results
*
* @param array $query
* @return array|null
*/
public function fetchImageQuery( $query ) {
$languageCode = MediaWikiServices::getInstance()->getMainConfig()
->get( MainConfigNames::LanguageCode );
$query = array_merge( $query,
[
'format' => 'json',
'action' => 'query',
'redirects' => 'true'
] );
if ( !isset( $query['uselang'] ) ) { // uselang is unset or null
$query['uselang'] = $languageCode;
}
$data = $this->httpGetCached( 'Metadata', $query, $this->apiMetadataExpiry );
if ( $data ) {
return FormatJson::decode( $data, true );
} else {
return null;
}
}
/**
* @param array $data
* @return array|false
*/
public function getImageInfo( $data ) {
if ( $data && isset( $data['query']['pages'] ) ) {
foreach ( $data['query']['pages'] as $info ) {
if ( isset( $info['imageinfo'][0] ) ) {
$return = $info['imageinfo'][0];
if ( isset( $info['pageid'] ) ) {
$return['pageid'] = $info['pageid'];
}
return $return;
}
}
}
return false;
}
/**
* @param string $hash
* @return ForeignAPIFile[]
*/
public function findBySha1( $hash ) {
$results = $this->fetchImageQuery( [
'aisha1base36' => $hash,
'aiprop' => ForeignAPIFile::getProps(),
'list' => 'allimages',
] );
$ret = [];
if ( isset( $results['query']['allimages'] ) ) {
foreach ( $results['query']['allimages'] as $img ) {
// 1.14 was broken, doesn't return name attribute
if ( !isset( $img['name'] ) ) {
continue;
}
$ret[] = new ForeignAPIFile( Title::makeTitle( NS_FILE, $img['name'] ), $this, $img );
}
}
return $ret;
}
/**
* @param string $name
* @param int $width
* @param int $height
* @param array|null &$result Output-only parameter, guaranteed to become an array
* @param string $otherParams
*
* @return string|false
*/
private function getThumbUrl(
$name, $width = -1, $height = -1, &$result = null, $otherParams = ''
) {
$data = $this->fetchImageQuery( [
'titles' => 'File:' . $name,
'iiprop' => self::getIIProps(),
'iiurlwidth' => $width,
'iiurlheight' => $height,
'iiurlparam' => $otherParams,
'prop' => 'imageinfo' ] );
$info = $this->getImageInfo( $data );
if ( $data && $info && isset( $info['thumburl'] ) ) {
wfDebug( __METHOD__ . " got remote thumb " . $info['thumburl'] );
$result = $info;
return $info['thumburl'];
} else {
return false;
}
}
/**
* @param string $name
* @param int $width
* @param int $height
* @param string $otherParams
* @param string|null $lang Language code for language of error
* @return MediaTransformError|false
* @since 1.22
*/
public function getThumbError(
$name, $width = -1, $height = -1, $otherParams = '', $lang = null
) {
$data = $this->fetchImageQuery( [
'titles' => 'File:' . $name,
'iiprop' => self::getIIProps(),
'iiurlwidth' => $width,
'iiurlheight' => $height,
'iiurlparam' => $otherParams,
'prop' => 'imageinfo',
'uselang' => $lang,
] );
$info = $this->getImageInfo( $data );
if ( $data && $info && isset( $info['thumberror'] ) ) {
wfDebug( __METHOD__ . " got remote thumb error " . $info['thumberror'] );
return new MediaTransformError(
'thumbnail_error_remote',
$width,
$height,
$this->getDisplayName(),
$info['thumberror'] // already parsed message from foreign repo
);
} else {
return false;
}
}
/**
* Return the imageurl from cache if possible
*
* If the url has been requested today, get it from cache
* Otherwise retrieve remote thumb url, check for local file.
*
* @param string $name Is a dbkey form of a title
* @param int $width
* @param int $height
* @param string $params Other rendering parameters (page number, etc)
* from handler's makeParamString.
* @return string|false
*/
public function getThumbUrlFromCache( $name, $width, $height, $params = "" ) {
// We can't check the local cache using FileRepo functions because
// we override fileExistsBatch(). We have to use the FileBackend directly.
$backend = $this->getBackend(); // convenience
if ( !$this->canCacheThumbs() ) {
$result = null; // can't pass "null" by reference, but it's ok as default value
return $this->getThumbUrl( $name, $width, $height, $result, $params );
}
$key = $this->getLocalCacheKey( 'file-thumb-url', sha1( $name ) );
$sizekey = "$width:$height:$params";
/* Get the array of urls that we already know */
$knownThumbUrls = $this->wanCache->get( $key );
if ( !$knownThumbUrls ) {
/* No knownThumbUrls for this file */
$knownThumbUrls = [];
} elseif ( isset( $knownThumbUrls[$sizekey] ) ) {
wfDebug( __METHOD__ . ': Got thumburl from local cache: ' .
"{$knownThumbUrls[$sizekey]}" );
return $knownThumbUrls[$sizekey];
}
$metadata = null;
$foreignUrl = $this->getThumbUrl( $name, $width, $height, $metadata, $params );
if ( !$foreignUrl ) {
wfDebug( __METHOD__ . " Could not find thumburl" );
return false;
}
// We need the same filename as the remote one :)
$fileName = rawurldecode( pathinfo( $foreignUrl, PATHINFO_BASENAME ) );
if ( !$this->validateFilename( $fileName ) ) {
wfDebug( __METHOD__ . " The deduced filename $fileName is not safe" );
return false;
}
$localPath = $this->getZonePath( 'thumb' ) . "/" . $this->getHashPath( $name ) . $name;
$localFilename = $localPath . "/" . $fileName;
$localUrl = $this->getZoneUrl( 'thumb' ) . "/" . $this->getHashPath( $name ) .
rawurlencode( $name ) . "/" . rawurlencode( $fileName );
if ( $backend->fileExists( [ 'src' => $localFilename ] )
&& isset( $metadata['timestamp'] )
) {
wfDebug( __METHOD__ . " Thumbnail was already downloaded before" );
$modified = (int)wfTimestamp( TS_UNIX, $backend->getFileTimestamp( [ 'src' => $localFilename ] ) );
$remoteModified = (int)wfTimestamp( TS_UNIX, $metadata['timestamp'] );
$current = (int)wfTimestamp( TS_UNIX );
$diff = abs( $modified - $current );
if ( $remoteModified < $modified && $diff < $this->fileCacheExpiry ) {
/* Use our current and already downloaded thumbnail */
$knownThumbUrls[$sizekey] = $localUrl;
$this->wanCache->set( $key, $knownThumbUrls, $this->apiThumbCacheExpiry );
return $localUrl;
}
/* There is a new Commons file, or existing thumbnail older than a month */
}
$thumb = self::httpGet( $foreignUrl, 'default', [], $mtime );
if ( !$thumb ) {
wfDebug( __METHOD__ . " Could not download thumb" );
return false;
}
# @todo FIXME: Delete old thumbs that aren't being used. Maintenance script?
$backend->prepare( [ 'dir' => dirname( $localFilename ) ] );
$params = [ 'dst' => $localFilename, 'content' => $thumb ];
if ( !$backend->quickCreate( $params )->isOK() ) {
wfDebug( __METHOD__ . " could not write to thumb path '$localFilename'" );
return $foreignUrl;
}
$knownThumbUrls[$sizekey] = $localUrl;
$ttl = $mtime
? $this->wanCache->adaptiveTTL( $mtime, $this->apiThumbCacheExpiry )
: $this->apiThumbCacheExpiry;
$this->wanCache->set( $key, $knownThumbUrls, $ttl );
wfDebug( __METHOD__ . " got local thumb $localUrl, saving to cache" );
return $localUrl;
}
/**
* @see FileRepo::getZoneUrl()
* @param string $zone
* @param string|null $ext Optional file extension
* @return string
*/
public function getZoneUrl( $zone, $ext = null ) {
switch ( $zone ) {
case 'public':
return $this->url;
case 'thumb':
return $this->thumbUrl;
default:
return parent::getZoneUrl( $zone, $ext );
}
}
/**
* Get the local directory corresponding to one of the basic zones
* @param string $zone
* @return null|string|false
*/
public function getZonePath( $zone ) {
$supported = [ 'public', 'thumb' ];
if ( in_array( $zone, $supported ) ) {
return parent::getZonePath( $zone );
}
return false;
}
/**
* Are we locally caching the thumbnails?
* @return bool
*/
public function canCacheThumbs() {
return ( $this->apiThumbCacheExpiry > 0 );
}
/**
* The user agent the ForeignAPIRepo will use.
* @return string
*/
public static function getUserAgent() {
return MediaWikiServices::getInstance()->getHttpRequestFactory()->getUserAgent() .
" ForeignAPIRepo/" . self::VERSION;
}
/**
* Get information about the repo - overrides/extends the parent
* class's information.
* @return array
* @since 1.22
*/
public function getInfo() {
$info = parent::getInfo();
$info['apiurl'] = $this->mApiBase;
$query = [
'format' => 'json',
'action' => 'query',
'meta' => 'siteinfo',
'siprop' => 'general',
];
$data = $this->httpGetCached( 'SiteInfo', $query, 7200 );
if ( $data ) {
$siteInfo = FormatJson::decode( $data, true );
$general = $siteInfo['query']['general'];
$info['articlepath'] = $general['articlepath'];
$info['server'] = $general['server'];
if ( !isset( $info['favicon'] ) && isset( $general['favicon'] ) ) {
$info['favicon'] = $general['favicon'];
}
}
return $info;
}
/**
* @param string $url
* @param string $timeout
* @param array $options
* @param int|false &$mtime Resulting Last-Modified UNIX timestamp if received
* @return string|false
*/
public static function httpGet(
$url, $timeout = 'default', $options = [], &$mtime = false
) {
$options['timeout'] = $timeout;
$url = MediaWikiServices::getInstance()->getUrlUtils()
->expand( $url, PROTO_HTTP );
wfDebug( "ForeignAPIRepo: HTTP GET: $url" );
if ( !$url ) {
return false;
}
$options['method'] = "GET";
if ( !isset( $options['timeout'] ) ) {
$options['timeout'] = 'default';
}
$options['userAgent'] = self::getUserAgent();
$req = MediaWikiServices::getInstance()->getHttpRequestFactory()
->create( $url, $options, __METHOD__ );
$status = $req->execute();
if ( $status->isOK() ) {
$lmod = $req->getResponseHeader( 'Last-Modified' );
$mtime = $lmod ? (int)wfTimestamp( TS_UNIX, $lmod ) : false;
return $req->getContent();
} else {
$logger = LoggerFactory::getInstance( 'http' );
$logger->warning(
$status->getWikiText( false, false, 'en' ),
[ 'caller' => 'ForeignAPIRepo::httpGet' ]
);
return false;
}
}
/**
* @return string
* @since 1.23
*/
protected static function getIIProps() {
return implode( '|', self::IMAGE_INFO_PROPS );
}
/**
* HTTP GET request to a mediawiki API (with caching)
* @param string $attribute Used in cache key creation, mostly
* @param array $query The query parameters for the API request
* @param int $cacheTTL Time to live for the memcached caching
* @return string|null
*/
public function httpGetCached( $attribute, $query, $cacheTTL = 3600 ) {
if ( $this->mApiBase ) {
$url = wfAppendQuery( $this->mApiBase, $query );
} else {
$url = $this->makeUrl( $query, 'api' );
}
return $this->wanCache->getWithSetCallback(
// Allow reusing the same cached data across wikis (T285271).
// This does not use getSharedCacheKey() because caching here
// is transparent to client wikis (which are not expected to issue purges).
$this->wanCache->makeGlobalKey( "filerepo-$attribute", sha1( $url ) ),
$cacheTTL,
function ( $curValue, &$ttl ) use ( $url ) {
$html = self::httpGet( $url, 'default', [], $mtime );
// FIXME: This should use the mtime from the api response body
// not the mtime from the last-modified header which usually is not set.
if ( $html !== false ) {
$ttl = $mtime ? $this->wanCache->adaptiveTTL( $mtime, $ttl ) : $ttl;
} else {
$ttl = $this->wanCache->adaptiveTTL( $mtime, $ttl );
$html = null; // caches negatives
}
return $html;
},
[ 'pcGroup' => 'http-get:3', 'pcTTL' => WANObjectCache::TTL_PROC_LONG ]
);
}
/**
* @param callable $callback
* @return never
*/
public function enumFiles( $callback ) {
throw new RuntimeException( 'enumFiles is not supported by ' . static::class );
}
/**
* @return never
*/
protected function assertWritableRepo() {
throw new LogicException( static::class . ': write operations are not supported.' );
}
}