Current File : /www/varak.net/wiki.varak.net/thumb.php
<?php
/**
* PHP script to stream out an image thumbnail.
*
* 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
* @ingroup Media
*/
use MediaWiki\Logger\LoggerFactory;
use MediaWiki\MediaWikiServices;
define( 'MW_NO_OUTPUT_COMPRESSION', 1 );
require __DIR__ . '/includes/WebStart.php';
// Don't use fancy MIME detection, just check the file extension for jpg/gif/png
$wgTrivialMimeDetection = true;
if ( defined( 'THUMB_HANDLER' ) ) {
// Called from thumb_handler.php via 404; extract params from the URI...
wfThumbHandle404();
} else {
// Called directly, use $_GET params
wfStreamThumb( $wgRequest->getQueryValues() );
}
$mediawiki = new MediaWiki();
$mediawiki->doPostOutputShutdown( 'fast' );
// --------------------------------------------------------------------------
/**
* Handle a thumbnail request via thumbnail file URL
*
* @return void
*/
function wfThumbHandle404() {
global $wgArticlePath;
# Set action base paths so that WebRequest::getPathInfo()
# recognizes the "X" as the 'title' in ../thumb_handler.php/X urls.
# Note: If Custom per-extension repo paths are set, this may break.
$repo = RepoGroup::singleton()->getLocalRepo();
$oldArticlePath = $wgArticlePath;
$wgArticlePath = $repo->getZoneUrl( 'thumb' ) . '/$1';
$matches = WebRequest::getPathInfo();
$wgArticlePath = $oldArticlePath;
if ( !isset( $matches['title'] ) ) {
wfThumbError( 404, 'Could not determine the name of the requested thumbnail.' );
return;
}
$params = wfExtractThumbRequestInfo( $matches['title'] ); // basic wiki URL param extracting
if ( $params == null ) {
wfThumbError( 400, 'The specified thumbnail parameters are not recognized.' );
return;
}
wfStreamThumb( $params ); // stream the thumbnail
}
/**
* Stream a thumbnail specified by parameters
*
* @param array $params List of thumbnailing parameters. In addition to parameters
* passed to the MediaHandler, this may also includes the keys:
* f (for filename), archived (if archived file), temp (if temp file),
* w (alias for width), p (alias for page), r (ignored; historical),
* rel404 (path for render on 404 to verify hash path correct),
* thumbName (thumbnail name to potentially extract more parameters from
* e.g. 'lossy-page1-120px-Foo.tiff' would add page, lossy and width
* to the parameters)
* @return void
*/
function wfStreamThumb( array $params ) {
global $wgVaryOnXFP;
$headers = []; // HTTP headers to send
$fileName = $params['f'] ?? '';
// Backwards compatibility parameters
if ( isset( $params['w'] ) ) {
$params['width'] = $params['w'];
unset( $params['w'] );
}
if ( isset( $params['width'] ) && substr( $params['width'], -2 ) == 'px' ) {
// strip the px (pixel) suffix, if found
$params['width'] = substr( $params['width'], 0, -2 );
}
if ( isset( $params['p'] ) ) {
$params['page'] = $params['p'];
}
// Is this a thumb of an archived file?
$isOld = ( isset( $params['archived'] ) && $params['archived'] );
unset( $params['archived'] ); // handlers don't care
// Is this a thumb of a temp file?
$isTemp = ( isset( $params['temp'] ) && $params['temp'] );
unset( $params['temp'] ); // handlers don't care
// Some basic input validation
$fileName = strtr( $fileName, '\\/', '__' );
// Actually fetch the image. Method depends on whether it is archived or not.
if ( $isTemp ) {
$repo = RepoGroup::singleton()->getLocalRepo()->getTempRepo();
$img = new UnregisteredLocalFile( null, $repo,
# Temp files are hashed based on the name without the timestamp.
# The thumbnails will be hashed based on the entire name however.
# @todo fix this convention to actually be reasonable.
$repo->getZonePath( 'public' ) . '/' . $repo->getTempHashPath( $fileName ) . $fileName
);
} elseif ( $isOld ) {
// Format is <timestamp>!<name>
$bits = explode( '!', $fileName, 2 );
if ( count( $bits ) != 2 ) {
wfThumbError( 404, wfMessage( 'badtitletext' )->parse() );
return;
}
$title = Title::makeTitleSafe( NS_FILE, $bits[1] );
if ( !$title ) {
wfThumbError( 404, wfMessage( 'badtitletext' )->parse() );
return;
}
$img = RepoGroup::singleton()->getLocalRepo()->newFromArchiveName( $title, $fileName );
} else {
$img = wfLocalFile( $fileName );
}
// Check the source file title
if ( !$img ) {
wfThumbError( 404, wfMessage( 'badtitletext' )->parse() );
return;
}
// Check permissions if there are read restrictions
$varyHeader = [];
if ( !in_array( 'read', User::getGroupPermissions( [ '*' ] ), true ) ) {
if ( !$img->getTitle() || !$img->getTitle()->userCan( 'read' ) ) {
wfThumbError( 403, 'Access denied. You do not have permission to access ' .
'the source file.' );
return;
}
$headers[] = 'Cache-Control: private';
$varyHeader[] = 'Cookie';
}
// Check if the file is hidden
if ( $img->isDeleted( File::DELETED_FILE ) ) {
wfThumbErrorText( 404, "The source file '$fileName' does not exist." );
return;
}
// Do rendering parameters extraction from thumbnail name.
if ( isset( $params['thumbName'] ) ) {
$params = wfExtractThumbParams( $img, $params );
}
if ( $params == null ) {
wfThumbError( 400, 'The specified thumbnail parameters are not recognized.' );
return;
}
// Check the source file storage path
if ( !$img->exists() ) {
$redirectedLocation = false;
if ( !$isTemp ) {
// Check for file redirect
// Since redirects are associated with pages, not versions of files,
// we look for the most current version to see if its a redirect.
$possRedirFile = RepoGroup::singleton()->getLocalRepo()->findFile( $img->getName() );
if ( $possRedirFile && !is_null( $possRedirFile->getRedirected() ) ) {
$redirTarget = $possRedirFile->getName();
$targetFile = wfLocalFile( Title::makeTitleSafe( NS_FILE, $redirTarget ) );
if ( $targetFile->exists() ) {
$newThumbName = $targetFile->thumbName( $params );
if ( $isOld ) {
/** @var array $bits */
$newThumbUrl = $targetFile->getArchiveThumbUrl(
$bits[0] . '!' . $targetFile->getName(), $newThumbName );
} else {
$newThumbUrl = $targetFile->getThumbUrl( $newThumbName );
}
$redirectedLocation = wfExpandUrl( $newThumbUrl, PROTO_CURRENT );
}
}
}
if ( $redirectedLocation ) {
// File has been moved. Give redirect.
$response = RequestContext::getMain()->getRequest()->response();
$response->statusHeader( 302 );
$response->header( 'Location: ' . $redirectedLocation );
$response->header( 'Expires: ' .
gmdate( 'D, d M Y H:i:s', time() + 12 * 3600 ) . ' GMT' );
if ( $wgVaryOnXFP ) {
$varyHeader[] = 'X-Forwarded-Proto';
}
if ( count( $varyHeader ) ) {
$response->header( 'Vary: ' . implode( ', ', $varyHeader ) );
}
$response->header( 'Content-Length: 0' );
return;
}
// If its not a redirect that has a target as a local file, give 404.
wfThumbErrorText( 404, "The source file '$fileName' does not exist." );
return;
} elseif ( $img->getPath() === false ) {
wfThumbErrorText( 400, "The source file '$fileName' is not locally accessible." );
return;
}
// Check IMS against the source file
// This means that clients can keep a cached copy even after it has been deleted on the server
if ( !empty( $_SERVER['HTTP_IF_MODIFIED_SINCE'] ) ) {
// Fix IE brokenness
$imsString = preg_replace( '/;.*$/', '', $_SERVER["HTTP_IF_MODIFIED_SINCE"] );
// Calculate time
Wikimedia\suppressWarnings();
$imsUnix = strtotime( $imsString );
Wikimedia\restoreWarnings();
if ( wfTimestamp( TS_UNIX, $img->getTimestamp() ) <= $imsUnix ) {
HttpStatus::header( 304 );
return;
}
}
$rel404 = $params['rel404'] ?? null;
unset( $params['r'] ); // ignore 'r' because we unconditionally pass File::RENDER
unset( $params['f'] ); // We're done with 'f' parameter.
unset( $params['rel404'] ); // moved to $rel404
// Get the normalized thumbnail name from the parameters...
try {
$thumbName = $img->thumbName( $params );
if ( !strlen( $thumbName ) ) { // invalid params?
throw new MediaTransformInvalidParametersException(
'Empty return from File::thumbName'
);
}
$thumbName2 = $img->thumbName( $params, File::THUMB_FULL_NAME ); // b/c; "long" style
} catch ( MediaTransformInvalidParametersException $e ) {
wfThumbError(
400,
'The specified thumbnail parameters are not valid: ' . $e->getMessage()
);
return;
} catch ( MWException $e ) {
wfThumbError( 500, $e->getHTML(), 'Exception caught while extracting thumb name',
[ 'exception' => $e ] );
return;
}
// For 404 handled thumbnails, we only use the base name of the URI
// for the thumb params and the parent directory for the source file name.
// Check that the zone relative path matches up so squid caches won't pick
// up thumbs that would not be purged on source file deletion (T36231).
if ( $rel404 !== null ) { // thumbnail was handled via 404
if ( rawurldecode( $rel404 ) === $img->getThumbRel( $thumbName ) ) {
// Request for the canonical thumbnail name
} elseif ( rawurldecode( $rel404 ) === $img->getThumbRel( $thumbName2 ) ) {
// Request for the "long" thumbnail name; redirect to canonical name
$response = RequestContext::getMain()->getRequest()->response();
$response->statusHeader( 301 );
$response->header( 'Location: ' .
wfExpandUrl( $img->getThumbUrl( $thumbName ), PROTO_CURRENT ) );
$response->header( 'Expires: ' .
gmdate( 'D, d M Y H:i:s', time() + 7 * 86400 ) . ' GMT' );
if ( $wgVaryOnXFP ) {
$varyHeader[] = 'X-Forwarded-Proto';
}
if ( count( $varyHeader ) ) {
$response->header( 'Vary: ' . implode( ', ', $varyHeader ) );
}
return;
} else {
wfThumbErrorText( 404, "The given path of the specified thumbnail is incorrect;
expected '" . $img->getThumbRel( $thumbName ) . "' but got '" .
rawurldecode( $rel404 ) . "'." );
return;
}
}
$dispositionType = isset( $params['download'] ) ? 'attachment' : 'inline';
// Suggest a good name for users downloading this thumbnail
$headers[] =
"Content-Disposition: {$img->getThumbDisposition( $thumbName, $dispositionType )}";
if ( count( $varyHeader ) ) {
$headers[] = 'Vary: ' . implode( ', ', $varyHeader );
}
// Stream the file if it exists already...
$thumbPath = $img->getThumbPath( $thumbName );
if ( $img->getRepo()->fileExists( $thumbPath ) ) {
$starttime = microtime( true );
$status = $img->getRepo()->streamFileWithStatus( $thumbPath, $headers );
$streamtime = microtime( true ) - $starttime;
if ( $status->isOK() ) {
MediaWikiServices::getInstance()->getStatsdDataFactory()->timing(
'media.thumbnail.stream', $streamtime
);
} else {
wfThumbError( 500, 'Could not stream the file', null, [ 'file' => $thumbName,
'path' => $thumbPath, 'error' => $status->getWikiText( false, false, 'en' ) ] );
}
return;
}
$user = RequestContext::getMain()->getUser();
if ( !wfThumbIsStandard( $img, $params ) && $user->pingLimiter( 'renderfile-nonstandard' ) ) {
wfThumbError( 429, wfMessage( 'actionthrottledtext' )->parse() );
return;
} elseif ( $user->pingLimiter( 'renderfile' ) ) {
wfThumbError( 429, wfMessage( 'actionthrottledtext' )->parse() );
return;
}
$thumbProxyUrl = $img->getRepo()->getThumbProxyUrl();
if ( strlen( $thumbProxyUrl ) ) {
wfProxyThumbnailRequest( $img, $thumbName );
// No local fallback when in proxy mode
return;
} else {
// Generate the thumbnail locally
list( $thumb, $errorMsg ) = wfGenerateThumbnail( $img, $params, $thumbName, $thumbPath );
}
/** @var MediaTransformOutput|MediaTransformError|bool $thumb */
// Check for thumbnail generation errors...
$msg = wfMessage( 'thumbnail_error' );
$errorCode = 500;
if ( !$thumb ) {
$errorMsg = $errorMsg ?: $msg->rawParams( 'File::transform() returned false' )->escaped();
if ( $errorMsg instanceof MessageSpecifier &&
$errorMsg->getKey() === 'thumbnail_image-failure-limit'
) {
$errorCode = 429;
}
} elseif ( $thumb->isError() ) {
$errorMsg = $thumb->getHtmlMsg();
$errorCode = $thumb->getHttpStatusCode();
} elseif ( !$thumb->hasFile() ) {
$errorMsg = $msg->rawParams( 'No path supplied in thumbnail object' )->escaped();
} elseif ( $thumb->fileIsSource() ) {
$errorMsg = $msg
->rawParams( 'Image was not scaled, is the requested width bigger than the source?' )
->escaped();
$errorCode = 400;
}
if ( $errorMsg !== false ) {
wfThumbError( $errorCode, $errorMsg, null, [ 'file' => $thumbName, 'path' => $thumbPath ] );
} else {
// Stream the file if there were no errors
$status = $thumb->streamFileWithStatus( $headers );
if ( !$status->isOK() ) {
wfThumbError( 500, 'Could not stream the file', null, [
'file' => $thumbName, 'path' => $thumbPath,
'error' => $status->getWikiText( false, false, 'en' ) ] );
}
}
}
/**
* Proxies thumbnail request to a service that handles thumbnailing
*
* @param File $img
* @param string $thumbName
*/
function wfProxyThumbnailRequest( $img, $thumbName ) {
$thumbProxyUrl = $img->getRepo()->getThumbProxyUrl();
// Instead of generating the thumbnail ourselves, we proxy the request to another service
$thumbProxiedUrl = $thumbProxyUrl . $img->getThumbRel( $thumbName );
$req = MWHttpRequest::factory( $thumbProxiedUrl );
$secret = $img->getRepo()->getThumbProxySecret();
// Pass a secret key shared with the proxied service if any
if ( strlen( $secret ) ) {
$req->setHeader( 'X-Swift-Secret', $secret );
}
// Send request to proxied service
$status = $req->execute();
// Simply serve the response from the proxied service as-is
header( 'HTTP/1.1 ' . $req->getStatus() );
$headers = $req->getResponseHeaders();
foreach ( $headers as $key => $values ) {
foreach ( $values as $value ) {
header( $key . ': ' . $value, false );
}
}
echo $req->getContent();
}
/**
* Actually try to generate a new thumbnail
*
* @param File $file
* @param array $params
* @param string $thumbName
* @param string $thumbPath
* @return array (MediaTransformOutput|bool, string|bool error message HTML)
*/
function wfGenerateThumbnail( File $file, array $params, $thumbName, $thumbPath ) {
global $wgAttemptFailureEpoch;
$cache = ObjectCache::getLocalClusterInstance();
$key = $cache->makeKey(
'attempt-failures',
$wgAttemptFailureEpoch,
$file->getRepo()->getName(),
$file->getSha1(),
md5( $thumbName )
);
// Check if this file keeps failing to render
if ( $cache->get( $key ) >= 4 ) {
return [ false, wfMessage( 'thumbnail_image-failure-limit', 4 ) ];
}
$done = false;
// Record failures on PHP fatals in addition to caching exceptions
register_shutdown_function( function () use ( $cache, &$done, $key ) {
if ( !$done ) { // transform() gave a fatal
// Randomize TTL to reduce stampedes
$cache->incrWithInit( $key, $cache::TTL_HOUR + mt_rand( 0, 300 ) );
}
} );
$thumb = false;
$errorHtml = false;
// guard thumbnail rendering with PoolCounter to avoid stampedes
// expensive files use a separate PoolCounter config so it is possible
// to set up a global limit on them
if ( $file->isExpensiveToThumbnail() ) {
$poolCounterType = 'FileRenderExpensive';
} else {
$poolCounterType = 'FileRender';
}
// Thumbnail isn't already there, so create the new thumbnail...
try {
$work = new PoolCounterWorkViaCallback( $poolCounterType, sha1( $file->getName() ),
[
'doWork' => function () use ( $file, $params ) {
return $file->transform( $params, File::RENDER_NOW );
},
'doCachedWork' => function () use ( $file, $params, $thumbPath ) {
// If the worker that finished made this thumbnail then use it.
// Otherwise, it probably made a different thumbnail for this file.
return $file->getRepo()->fileExists( $thumbPath )
? $file->transform( $params, File::RENDER_NOW )
: false; // retry once more in exclusive mode
},
'error' => function ( Status $status ) {
return wfMessage( 'generic-pool-error' )->parse() . '<hr>' . $status->getHTML();
}
]
);
$result = $work->execute();
if ( $result instanceof MediaTransformOutput ) {
$thumb = $result;
} elseif ( is_string( $result ) ) { // error
$errorHtml = $result;
}
} catch ( Exception $e ) {
// Tried to select a page on a non-paged file?
}
/** @noinspection PhpUnusedLocalVariableInspection */
$done = true; // no PHP fatal occurred
if ( !$thumb || $thumb->isError() ) {
// Randomize TTL to reduce stampedes
$cache->incrWithInit( $key, $cache::TTL_HOUR + mt_rand( 0, 300 ) );
}
return [ $thumb, $errorHtml ];
}
/**
* Convert pathinfo type parameter, into normal request parameters
*
* So for example, if the request was redirected from
* /w/images/thumb/a/ab/Foo.png/120px-Foo.png. The $thumbRel parameter
* of this function would be set to "a/ab/Foo.png/120px-Foo.png".
* This method is responsible for turning that into an array
* with the folowing keys:
* * f => the filename (Foo.png)
* * rel404 => the whole thing (a/ab/Foo.png/120px-Foo.png)
* * archived => 1 (If the request is for an archived thumb)
* * temp => 1 (If the file is in the "temporary" zone)
* * thumbName => the thumbnail name, including parameters (120px-Foo.png)
*
* Transform specific parameters are set later via wfExtractThumbParams().
*
* @param string $thumbRel Thumbnail path relative to the thumb zone
* @return array|null Associative params array or null
*/
function wfExtractThumbRequestInfo( $thumbRel ) {
$repo = RepoGroup::singleton()->getLocalRepo();
$hashDirReg = $subdirReg = '';
$hashLevels = $repo->getHashLevels();
for ( $i = 0; $i < $hashLevels; $i++ ) {
$subdirReg .= '[0-9a-f]';
$hashDirReg .= "$subdirReg/";
}
// Check if this is a thumbnail of an original in the local file repo
if ( preg_match( "!^((archive/)?$hashDirReg([^/]*)/([^/]*))$!", $thumbRel, $m ) ) {
list( /*all*/, $rel, $archOrTemp, $filename, $thumbname ) = $m;
// Check if this is a thumbnail of an temp file in the local file repo
} elseif ( preg_match( "!^(temp/)($hashDirReg([^/]*)/([^/]*))$!", $thumbRel, $m ) ) {
list( /*all*/, $archOrTemp, $rel, $filename, $thumbname ) = $m;
} else {
return null; // not a valid looking thumbnail request
}
$params = [ 'f' => $filename, 'rel404' => $rel ];
if ( $archOrTemp === 'archive/' ) {
$params['archived'] = 1;
} elseif ( $archOrTemp === 'temp/' ) {
$params['temp'] = 1;
}
$params['thumbName'] = $thumbname;
return $params;
}
/**
* Convert a thumbnail name (122px-foo.png) to parameters, using
* file handler.
*
* @param File $file File object for file in question
* @param array $params Array of parameters so far
* @return array Parameters array with more parameters
*/
function wfExtractThumbParams( $file, $params ) {
if ( !isset( $params['thumbName'] ) ) {
throw new InvalidArgumentException( "No thumbnail name passed to wfExtractThumbParams" );
}
$thumbname = $params['thumbName'];
unset( $params['thumbName'] );
// FIXME: Files in the temp zone don't set a MIME type, which means
// they don't have a handler. Which means we can't parse the param
// string. However, not a big issue as what good is a param string
// if you have no handler to make use of the param string and
// actually generate the thumbnail.
$handler = $file->getHandler();
// Based on UploadStash::parseKey
$fileNamePos = strrpos( $thumbname, $params['f'] );
if ( $fileNamePos === false ) {
// Maybe using a short filename? (see FileRepo::nameForThumb)
$fileNamePos = strrpos( $thumbname, 'thumbnail' );
}
if ( $handler && $fileNamePos !== false ) {
$paramString = substr( $thumbname, 0, $fileNamePos - 1 );
$extraParams = $handler->parseParamString( $paramString );
if ( $extraParams !== false ) {
return $params + $extraParams;
}
}
// As a last ditch fallback, use the traditional common parameters
if ( preg_match( '!^(page(\d*)-)*(\d*)px-[^/]*$!', $thumbname, $matches ) ) {
list( /* all */, /* pagefull */, $pagenum, $size ) = $matches;
$params['width'] = $size;
if ( $pagenum ) {
$params['page'] = $pagenum;
}
return $params; // valid thumbnail URL
}
return null;
}
/**
* Output a thumbnail generation error message
*
* @param int $status
* @param string $msgText Plain text (will be html escaped)
* @return void
*/
function wfThumbErrorText( $status, $msgText ) {
wfThumbError( $status, htmlspecialchars( $msgText, ENT_NOQUOTES ) );
}
/**
* Output a thumbnail generation error message
*
* @param int $status
* @param string $msgHtml HTML
* @param string|null $msgText Short error description, for internal logging. Defaults to $msgHtml.
* Only used for HTTP 500 errors.
* @param array $context Error context, for internal logging. Only used for HTTP 500 errors.
* @return void
*/
function wfThumbError( $status, $msgHtml, $msgText = null, $context = [] ) {
global $wgShowHostnames;
header( 'Cache-Control: no-cache' );
header( 'Content-Type: text/html; charset=utf-8' );
if ( $status == 400 || $status == 404 || $status == 429 ) {
HttpStatus::header( $status );
} elseif ( $status == 403 ) {
HttpStatus::header( 403 );
header( 'Vary: Cookie' );
} else {
LoggerFactory::getInstance( 'thumb' )->error( $msgText ?: $msgHtml, $context );
HttpStatus::header( 500 );
}
if ( $wgShowHostnames ) {
header( 'X-MW-Thumbnail-Renderer: ' . wfHostname() );
$url = htmlspecialchars(
$_SERVER['REQUEST_URI'] ?? '',
ENT_NOQUOTES
);
$hostname = htmlspecialchars( wfHostname(), ENT_NOQUOTES );
$debug = "<!-- $url -->\n<!-- $hostname -->\n";
} else {
$debug = '';
}
$content = <<<EOT
<!DOCTYPE html>
<html><head>
<meta charset="UTF-8" />
<title>Error generating thumbnail</title>
</head>
<body>
<h1>Error generating thumbnail</h1>
<p>
$msgHtml
</p>
$debug
</body>
</html>
EOT;
header( 'Content-Length: ' . strlen( $content ) );
echo $content;
}
Mini Shell