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diff --git a/www/wiki/includes/media/MediaHandler.php b/www/wiki/includes/media/MediaHandler.php
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+<?php
+/**
+ * Media-handling base classes and generic functionality.
+ *
+ * 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\MediaWikiServices;
+
+/**
+ * Base media handler class
+ *
+ * @ingroup Media
+ */
+abstract class MediaHandler {
+	const TRANSFORM_LATER = 1;
+	const METADATA_GOOD = true;
+	const METADATA_BAD = false;
+	const METADATA_COMPATIBLE = 2; // for old but backwards compatible.
+	/**
+	 * Max length of error logged by logErrorForExternalProcess()
+	 */
+	const MAX_ERR_LOG_SIZE = 65535;
+
+	/**
+	 * Get a MediaHandler for a given MIME type from the instance cache
+	 *
+	 * @param string $type
+	 * @return MediaHandler|bool
+	 */
+	static function getHandler( $type ) {
+		return MediaWikiServices::getInstance()
+			->getMediaHandlerFactory()->getHandler( $type );
+	}
+
+	/**
+	 * Get an associative array mapping magic word IDs to parameter names.
+	 * Will be used by the parser to identify parameters.
+	 */
+	abstract public function getParamMap();
+
+	/**
+	 * Validate a thumbnail parameter at parse time.
+	 * Return true to accept the parameter, and false to reject it.
+	 * If you return false, the parser will do something quiet and forgiving.
+	 *
+	 * @param string $name
+	 * @param mixed $value
+	 */
+	abstract public function validateParam( $name, $value );
+
+	/**
+	 * Merge a parameter array into a string appropriate for inclusion in filenames
+	 *
+	 * @param array $params Array of parameters that have been through normaliseParams.
+	 * @return string
+	 */
+	abstract public function makeParamString( $params );
+
+	/**
+	 * Parse a param string made with makeParamString back into an array
+	 *
+	 * @param string $str The parameter string without file name (e.g. 122px)
+	 * @return array|bool Array of parameters or false on failure.
+	 */
+	abstract public function parseParamString( $str );
+
+	/**
+	 * Changes the parameter array as necessary, ready for transformation.
+	 * Should be idempotent.
+	 * Returns false if the parameters are unacceptable and the transform should fail
+	 * @param File $image
+	 * @param array &$params
+	 */
+	abstract function normaliseParams( $image, &$params );
+
+	/**
+	 * Get an image size array like that returned by getimagesize(), or false if it
+	 * can't be determined.
+	 *
+	 * This function is used for determining the width, height and bitdepth directly
+	 * from an image. The results are stored in the database in the img_width,
+	 * img_height, img_bits fields.
+	 *
+	 * @note If this is a multipage file, return the width and height of the
+	 *  first page.
+	 *
+	 * @param File|FSFile $image The image object, or false if there isn't one.
+	 *   Warning, FSFile::getPropsFromPath might pass an FSFile instead of File (!)
+	 * @param string $path The filename
+	 * @return array|bool Follow the format of PHP getimagesize() internal function.
+	 *   See https://secure.php.net/getimagesize. MediaWiki will only ever use the
+	 *   first two array keys (the width and height), and the 'bits' associative
+	 *   key. All other array keys are ignored. Returning a 'bits' key is optional
+	 *   as not all formats have a notion of "bitdepth". Returns false on failure.
+	 */
+	abstract function getImageSize( $image, $path );
+
+	/**
+	 * Get handler-specific metadata which will be saved in the img_metadata field.
+	 *
+	 * @param File|FSFile $image The image object, or false if there isn't one.
+	 *   Warning, FSFile::getPropsFromPath might pass an FSFile instead of File (!)
+	 * @param string $path The filename
+	 * @return string A string of metadata in php serialized form (Run through serialize())
+	 */
+	function getMetadata( $image, $path ) {
+		return '';
+	}
+
+	/**
+	 * Get metadata version.
+	 *
+	 * This is not used for validating metadata, this is used for the api when returning
+	 * metadata, since api content formats should stay the same over time, and so things
+	 * using ForeignApiRepo can keep backwards compatibility
+	 *
+	 * All core media handlers share a common version number, and extensions can
+	 * use the GetMetadataVersion hook to append to the array (they should append a unique
+	 * string so not to get confusing). If there was a media handler named 'foo' with metadata
+	 * version 3 it might add to the end of the array the element 'foo=3'. if the core metadata
+	 * version is 2, the end version string would look like '2;foo=3'.
+	 *
+	 * @return string Version string
+	 */
+	static function getMetadataVersion() {
+		$version = [ '2' ]; // core metadata version
+		Hooks::run( 'GetMetadataVersion', [ &$version ] );
+
+		return implode( ';', $version );
+	}
+
+	/**
+	 * Convert metadata version.
+	 *
+	 * By default just returns $metadata, but can be used to allow
+	 * media handlers to convert between metadata versions.
+	 *
+	 * @param string|array $metadata Metadata array (serialized if string)
+	 * @param int $version Target version
+	 * @return array Serialized metadata in specified version, or $metadata on fail.
+	 */
+	function convertMetadataVersion( $metadata, $version = 1 ) {
+		if ( !is_array( $metadata ) ) {
+			// unserialize to keep return parameter consistent.
+			Wikimedia\suppressWarnings();
+			$ret = unserialize( $metadata );
+			Wikimedia\restoreWarnings();
+
+			return $ret;
+		}
+
+		return $metadata;
+	}
+
+	/**
+	 * Get a string describing the type of metadata, for display purposes.
+	 *
+	 * @note This method is currently unused.
+	 * @param File $image
+	 * @return string
+	 */
+	function getMetadataType( $image ) {
+		return false;
+	}
+
+	/**
+	 * Check if the metadata string is valid for this handler.
+	 * If it returns MediaHandler::METADATA_BAD (or false), Image
+	 * will reload the metadata from the file and update the database.
+	 * MediaHandler::METADATA_GOOD for if the metadata is a-ok,
+	 * MediaHandler::METADATA_COMPATIBLE if metadata is old but backwards
+	 * compatible (which may or may not trigger a metadata reload).
+	 *
+	 * @note Returning self::METADATA_BAD will trigger a metadata reload from
+	 *  file on page view. Always returning this from a broken file, or suddenly
+	 *  triggering as bad metadata for a large number of files can cause
+	 *  performance problems.
+	 * @param File $image
+	 * @param string $metadata The metadata in serialized form
+	 * @return bool
+	 */
+	function isMetadataValid( $image, $metadata ) {
+		return self::METADATA_GOOD;
+	}
+
+	/**
+	 * Get an array of standard (FormatMetadata type) metadata values.
+	 *
+	 * The returned data is largely the same as that from getMetadata(),
+	 * but formatted in a standard, stable, handler-independent way.
+	 * The idea being that some values like ImageDescription or Artist
+	 * are universal and should be retrievable in a handler generic way.
+	 *
+	 * The specific properties are the type of properties that can be
+	 * handled by the FormatMetadata class. These values are exposed to the
+	 * user via the filemetadata parser function.
+	 *
+	 * Details of the response format of this function can be found at
+	 * https://www.mediawiki.org/wiki/Manual:File_metadata_handling
+	 * tl/dr: the response is an associative array of
+	 * properties keyed by name, but the value can be complex. You probably
+	 * want to call one of the FormatMetadata::flatten* functions on the
+	 * property values before using them, or call
+	 * FormatMetadata::getFormattedData() on the full response array, which
+	 * transforms all values into prettified, human-readable text.
+	 *
+	 * Subclasses overriding this function must return a value which is a
+	 * valid API response fragment (all associative array keys are valid
+	 * XML tagnames).
+	 *
+	 * Note, if the file simply has no metadata, but the handler supports
+	 * this interface, it should return an empty array, not false.
+	 *
+	 * @param File $file
+	 * @return array|bool False if interface not supported
+	 * @since 1.23
+	 */
+	public function getCommonMetaArray( File $file ) {
+		return false;
+	}
+
+	/**
+	 * Get a MediaTransformOutput object representing an alternate of the transformed
+	 * output which will call an intermediary thumbnail assist script.
+	 *
+	 * Used when the repository has a thumbnailScriptUrl option configured.
+	 *
+	 * Return false to fall back to the regular getTransform().
+	 * @param File $image
+	 * @param string $script
+	 * @param array $params
+	 * @return bool|ThumbnailImage
+	 */
+	function getScriptedTransform( $image, $script, $params ) {
+		return false;
+	}
+
+	/**
+	 * Get a MediaTransformOutput object representing the transformed output. Does not
+	 * actually do the transform.
+	 *
+	 * @param File $image
+	 * @param string $dstPath Filesystem destination path
+	 * @param string $dstUrl Destination URL to use in output HTML
+	 * @param array $params Arbitrary set of parameters validated by $this->validateParam()
+	 * @return MediaTransformOutput
+	 */
+	final function getTransform( $image, $dstPath, $dstUrl, $params ) {
+		return $this->doTransform( $image, $dstPath, $dstUrl, $params, self::TRANSFORM_LATER );
+	}
+
+	/**
+	 * Get a MediaTransformOutput object representing the transformed output. Does the
+	 * transform unless $flags contains self::TRANSFORM_LATER.
+	 *
+	 * @param File $image
+	 * @param string $dstPath Filesystem destination path
+	 * @param string $dstUrl Destination URL to use in output HTML
+	 * @param array $params Arbitrary set of parameters validated by $this->validateParam()
+	 *   Note: These parameters have *not* gone through $this->normaliseParams()
+	 * @param int $flags A bitfield, may contain self::TRANSFORM_LATER
+	 * @return MediaTransformOutput
+	 */
+	abstract function doTransform( $image, $dstPath, $dstUrl, $params, $flags = 0 );
+
+	/**
+	 * Get the thumbnail extension and MIME type for a given source MIME type
+	 *
+	 * @param string $ext Extension of original file
+	 * @param string $mime MIME type of original file
+	 * @param array $params Handler specific rendering parameters
+	 * @return array Thumbnail extension and MIME type
+	 */
+	function getThumbType( $ext, $mime, $params = null ) {
+		$magic = MediaWiki\MediaWikiServices::getInstance()->getMimeAnalyzer();
+		if ( !$ext || $magic->isMatchingExtension( $ext, $mime ) === false ) {
+			// The extension is not valid for this MIME type and we do
+			// recognize the MIME type
+			$extensions = $magic->getExtensionsForType( $mime );
+			if ( $extensions ) {
+				return [ strtok( $extensions, ' ' ), $mime ];
+			}
+		}
+
+		// The extension is correct (true) or the MIME type is unknown to
+		// MediaWiki (null)
+		return [ $ext, $mime ];
+	}
+
+	/**
+	 * @deprecated since 1.30, use MediaHandler::getContentHeaders instead
+	 * @param array $metadata
+	 * @return array
+	 */
+	public function getStreamHeaders( $metadata ) {
+		wfDeprecated( __METHOD__, '1.30' );
+		return $this->getContentHeaders( $metadata );
+	}
+
+	/**
+	 * True if the handled types can be transformed
+	 *
+	 * @param File $file
+	 * @return bool
+	 */
+	public function canRender( $file ) {
+		return true;
+	}
+
+	/**
+	 * True if handled types cannot be displayed directly in a browser
+	 * but can be rendered
+	 *
+	 * @param File $file
+	 * @return bool
+	 */
+	public function mustRender( $file ) {
+		return false;
+	}
+
+	/**
+	 * True if the type has multi-page capabilities
+	 *
+	 * @param File $file
+	 * @return bool
+	 */
+	public function isMultiPage( $file ) {
+		return false;
+	}
+
+	/**
+	 * Page count for a multi-page document, false if unsupported or unknown
+	 *
+	 * @param File $file
+	 * @return bool
+	 */
+	function pageCount( File $file ) {
+		return false;
+	}
+
+	/**
+	 * The material is vectorized and thus scaling is lossless
+	 *
+	 * @param File $file
+	 * @return bool
+	 */
+	function isVectorized( $file ) {
+		return false;
+	}
+
+	/**
+	 * The material is an image, and is animated.
+	 * In particular, video material need not return true.
+	 * @note Before 1.20, this was a method of ImageHandler only
+	 *
+	 * @param File $file
+	 * @return bool
+	 */
+	function isAnimatedImage( $file ) {
+		return false;
+	}
+
+	/**
+	 * If the material is animated, we can animate the thumbnail
+	 * @since 1.20
+	 *
+	 * @param File $file
+	 * @return bool If material is not animated, handler may return any value.
+	 */
+	function canAnimateThumbnail( $file ) {
+		return true;
+	}
+
+	/**
+	 * False if the handler is disabled for all files
+	 * @return bool
+	 */
+	function isEnabled() {
+		return true;
+	}
+
+	/**
+	 * Get an associative array of page dimensions
+	 * Currently "width" and "height" are understood, but this might be
+	 * expanded in the future.
+	 * Returns false if unknown.
+	 *
+	 * It is expected that handlers for paged media (e.g. DjVuHandler)
+	 * will override this method so that it gives the correct results
+	 * for each specific page of the file, using the $page argument.
+	 *
+	 * @note For non-paged media, use getImageSize.
+	 *
+	 * @param File $image
+	 * @param int $page What page to get dimensions of
+	 * @return array|bool
+	 */
+	function getPageDimensions( File $image, $page ) {
+		$gis = $this->getImageSize( $image, $image->getLocalRefPath() );
+		if ( $gis ) {
+			return [
+				'width' => $gis[0],
+				'height' => $gis[1]
+			];
+		} else {
+			return false;
+		}
+	}
+
+	/**
+	 * Generic getter for text layer.
+	 * Currently overloaded by PDF and DjVu handlers
+	 * @param File $image
+	 * @param int $page Page number to get information for
+	 * @return bool|string Page text or false when no text found or if
+	 *   unsupported.
+	 */
+	function getPageText( File $image, $page ) {
+		return false;
+	}
+
+	/**
+	 * Get the text of the entire document.
+	 * @param File $file
+	 * @return bool|string The text of the document or false if unsupported.
+	 */
+	public function getEntireText( File $file ) {
+		$numPages = $file->pageCount();
+		if ( !$numPages ) {
+			// Not a multipage document
+			return $this->getPageText( $file, 1 );
+		}
+		$document = '';
+		for ( $i = 1; $i <= $numPages; $i++ ) {
+			$curPage = $this->getPageText( $file, $i );
+			if ( is_string( $curPage ) ) {
+				$document .= $curPage . "\n";
+			}
+		}
+		if ( $document !== '' ) {
+			return $document;
+		}
+		return false;
+	}
+
+	/**
+	 * Get an array structure that looks like this:
+	 *
+	 * [
+	 *    'visible' => [
+	 *       'Human-readable name' => 'Human readable value',
+	 *       ...
+	 *    ],
+	 *    'collapsed' => [
+	 *       'Human-readable name' => 'Human readable value',
+	 *       ...
+	 *    ]
+	 * ]
+	 * The UI will format this into a table where the visible fields are always
+	 * visible, and the collapsed fields are optionally visible.
+	 *
+	 * The function should return false if there is no metadata to display.
+	 */
+
+	/**
+	 * @todo FIXME: This interface is not very flexible. The media handler
+	 * should generate HTML instead. It can do all the formatting according
+	 * to some standard. That makes it possible to do things like visual
+	 * indication of grouped and chained streams in ogg container files.
+	 * @param File $image
+	 * @param bool|IContextSource $context Context to use (optional)
+	 * @return array|bool
+	 */
+	function formatMetadata( $image, $context = false ) {
+		return false;
+	}
+
+	/** sorts the visible/invisible field.
+	 * Split off from ImageHandler::formatMetadata, as used by more than
+	 * one type of handler.
+	 *
+	 * This is used by the media handlers that use the FormatMetadata class
+	 *
+	 * @param array $metadataArray
+	 * @param bool|IContextSource $context Context to use (optional)
+	 * @return array Array for use displaying metadata.
+	 */
+	function formatMetadataHelper( $metadataArray, $context = false ) {
+		$result = [
+			'visible' => [],
+			'collapsed' => []
+		];
+
+		$formatted = FormatMetadata::getFormattedData( $metadataArray, $context );
+		// Sort fields into visible and collapsed
+		$visibleFields = $this->visibleMetadataFields();
+		foreach ( $formatted as $name => $value ) {
+			$tag = strtolower( $name );
+			self::addMeta( $result,
+				in_array( $tag, $visibleFields ) ? 'visible' : 'collapsed',
+				'exif',
+				$tag,
+				$value
+			);
+		}
+
+		return $result;
+	}
+
+	/**
+	 * Get a list of metadata items which should be displayed when
+	 * the metadata table is collapsed.
+	 *
+	 * @return array Array of strings
+	 */
+	protected function visibleMetadataFields() {
+		return FormatMetadata::getVisibleFields();
+	}
+
+	/**
+	 * This is used to generate an array element for each metadata value
+	 * That array is then used to generate the table of metadata values
+	 * on the image page
+	 *
+	 * @param array &$array An array containing elements for each type of visibility
+	 *   and each of those elements being an array of metadata items. This function adds
+	 *   a value to that array.
+	 * @param string $visibility ('visible' or 'collapsed') if this value is hidden
+	 *   by default.
+	 * @param string $type Type of metadata tag (currently always 'exif')
+	 * @param string $id The name of the metadata tag (like 'artist' for example).
+	 *   its name in the table displayed is the message "$type-$id" (Ex exif-artist ).
+	 * @param string $value Thingy goes into a wikitext table; it used to be escaped but
+	 *   that was incompatible with previous practise of customized display
+	 *   with wikitext formatting via messages such as 'exif-model-value'.
+	 *   So the escaping is taken back out, but generally this seems a confusing
+	 *   interface.
+	 * @param bool|string $param Value to pass to the message for the name of the field
+	 *   as $1. Currently this parameter doesn't seem to ever be used.
+	 *
+	 * Note, everything here is passed through the parser later on (!)
+	 */
+	protected static function addMeta( &$array, $visibility, $type, $id, $value, $param = false ) {
+		$msg = wfMessage( "$type-$id", $param );
+		if ( $msg->exists() ) {
+			$name = $msg->text();
+		} else {
+			// This is for future compatibility when using instant commons.
+			// So as to not display as ugly a name if a new metadata
+			// property is defined that we don't know about
+			// (not a major issue since such a property would be collapsed
+			// by default).
+			wfDebug( __METHOD__ . ' Unknown metadata name: ' . $id . "\n" );
+			$name = wfEscapeWikiText( $id );
+		}
+		$array[$visibility][] = [
+			'id' => "$type-$id",
+			'name' => $name,
+			'value' => $value
+		];
+	}
+
+	/**
+	 * Short description. Shown on Special:Search results.
+	 *
+	 * @param File $file
+	 * @return string
+	 */
+	function getShortDesc( $file ) {
+		return self::getGeneralShortDesc( $file );
+	}
+
+	/**
+	 * Long description. Shown under image on image description page surounded by ().
+	 *
+	 * @param File $file
+	 * @return string
+	 */
+	function getLongDesc( $file ) {
+		return self::getGeneralLongDesc( $file );
+	}
+
+	/**
+	 * Used instead of getShortDesc if there is no handler registered for file.
+	 *
+	 * @param File $file
+	 * @return string
+	 */
+	static function getGeneralShortDesc( $file ) {
+		global $wgLang;
+
+		return htmlspecialchars( $wgLang->formatSize( $file->getSize() ) );
+	}
+
+	/**
+	 * Used instead of getLongDesc if there is no handler registered for file.
+	 *
+	 * @param File $file
+	 * @return string
+	 */
+	static function getGeneralLongDesc( $file ) {
+		return wfMessage( 'file-info' )->sizeParams( $file->getSize() )
+			->params( '<span class="mime-type">' . $file->getMimeType() . '</span>' )->parse();
+	}
+
+	/**
+	 * Calculate the largest thumbnail width for a given original file size
+	 * such that the thumbnail's height is at most $maxHeight.
+	 * @param int $boxWidth Width of the thumbnail box.
+	 * @param int $boxHeight Height of the thumbnail box.
+	 * @param int $maxHeight Maximum height expected for the thumbnail.
+	 * @return int
+	 */
+	public static function fitBoxWidth( $boxWidth, $boxHeight, $maxHeight ) {
+		$idealWidth = $boxWidth * $maxHeight / $boxHeight;
+		$roundedUp = ceil( $idealWidth );
+		if ( round( $roundedUp * $boxHeight / $boxWidth ) > $maxHeight ) {
+			return floor( $idealWidth );
+		} else {
+			return $roundedUp;
+		}
+	}
+
+	/**
+	 * Shown in file history box on image description page.
+	 *
+	 * @param File $file
+	 * @return string Dimensions
+	 */
+	function getDimensionsString( $file ) {
+		return '';
+	}
+
+	/**
+	 * Modify the parser object post-transform.
+	 *
+	 * This is often used to do $parser->addOutputHook(),
+	 * in order to add some javascript to render a viewer.
+	 * See TimedMediaHandler or OggHandler for an example.
+	 *
+	 * @param Parser $parser
+	 * @param File $file
+	 */
+	function parserTransformHook( $parser, $file ) {
+	}
+
+	/**
+	 * File validation hook called on upload.
+	 *
+	 * If the file at the given local path is not valid, or its MIME type does not
+	 * match the handler class, a Status object should be returned containing
+	 * relevant errors.
+	 *
+	 * @param string $fileName The local path to the file.
+	 * @return Status
+	 */
+	function verifyUpload( $fileName ) {
+		return Status::newGood();
+	}
+
+	/**
+	 * Check for zero-sized thumbnails. These can be generated when
+	 * no disk space is available or some other error occurs
+	 *
+	 * @param string $dstPath The location of the suspect file
+	 * @param int $retval Return value of some shell process, file will be deleted if this is non-zero
+	 * @return bool True if removed, false otherwise
+	 */
+	function removeBadFile( $dstPath, $retval = 0 ) {
+		if ( file_exists( $dstPath ) ) {
+			$thumbstat = stat( $dstPath );
+			if ( $thumbstat['size'] == 0 || $retval != 0 ) {
+				$result = unlink( $dstPath );
+
+				if ( $result ) {
+					wfDebugLog( 'thumbnail',
+						sprintf( 'Removing bad %d-byte thumbnail "%s". unlink() succeeded',
+							$thumbstat['size'], $dstPath ) );
+				} else {
+					wfDebugLog( 'thumbnail',
+						sprintf( 'Removing bad %d-byte thumbnail "%s". unlink() failed',
+							$thumbstat['size'], $dstPath ) );
+				}
+
+				return true;
+			}
+		}
+
+		return false;
+	}
+
+	/**
+	 * Remove files from the purge list.
+	 *
+	 * This is used by some video handlers to prevent ?action=purge
+	 * from removing a transcoded video, which is expensive to
+	 * regenerate.
+	 *
+	 * @see LocalFile::purgeThumbnails
+	 *
+	 * @param array &$files
+	 * @param array $options Purge options. Currently will always be
+	 *  an array with a single key 'forThumbRefresh' set to true.
+	 */
+	public function filterThumbnailPurgeList( &$files, $options ) {
+		// Do nothing
+	}
+
+	/**
+	 * True if the handler can rotate the media
+	 * @since 1.24 non-static. From 1.21-1.23 was static
+	 * @return bool
+	 */
+	public function canRotate() {
+		return false;
+	}
+
+	/**
+	 * On supporting image formats, try to read out the low-level orientation
+	 * of the file and return the angle that the file needs to be rotated to
+	 * be viewed.
+	 *
+	 * This information is only useful when manipulating the original file;
+	 * the width and height we normally work with is logical, and will match
+	 * any produced output views.
+	 *
+	 * For files we don't know, we return 0.
+	 *
+	 * @param File $file
+	 * @return int 0, 90, 180 or 270
+	 */
+	public function getRotation( $file ) {
+		return 0;
+	}
+
+	/**
+	 * Log an error that occurred in an external process
+	 *
+	 * Moved from BitmapHandler to MediaHandler with MediaWiki 1.23
+	 *
+	 * @since 1.23
+	 * @param int $retval
+	 * @param string $err Error reported by command. Anything longer than
+	 * MediaHandler::MAX_ERR_LOG_SIZE is stripped off.
+	 * @param string $cmd
+	 */
+	protected function logErrorForExternalProcess( $retval, $err, $cmd ) {
+		# Keep error output limited (T59985)
+		$errMessage = trim( substr( $err, 0, self::MAX_ERR_LOG_SIZE ) );
+
+		wfDebugLog( 'thumbnail',
+			sprintf( 'thumbnail failed on %s: error %d "%s" from "%s"',
+					wfHostname(), $retval, $errMessage, $cmd ) );
+	}
+
+	/**
+	 * Get list of languages file can be viewed in.
+	 *
+	 * @param File $file
+	 * @return string[] Array of language codes, or empty array if unsupported.
+	 * @since 1.23
+	 */
+	public function getAvailableLanguages( File $file ) {
+		return [];
+	}
+
+	/**
+	 * On file types that support renderings in multiple languages,
+	 * which language is used by default if unspecified.
+	 *
+	 * If getAvailableLanguages returns a non-empty array, this must return
+	 * a valid language code. Otherwise can return null if files of this
+	 * type do not support alternative language renderings.
+	 *
+	 * @param File $file
+	 * @return string|null Language code or null if multi-language not supported for filetype.
+	 * @since 1.23
+	 */
+	public function getDefaultRenderLanguage( File $file ) {
+		return null;
+	}
+
+	/**
+	 * If its an audio file, return the length of the file. Otherwise 0.
+	 *
+	 * File::getLength() existed for a long time, but was calling a method
+	 * that only existed in some subclasses of this class (The TMH ones).
+	 *
+	 * @param File $file
+	 * @return float Length in seconds
+	 * @since 1.23
+	 */
+	public function getLength( $file ) {
+		return 0.0;
+	}
+
+	/**
+	 * True if creating thumbnails from the file is large or otherwise resource-intensive.
+	 * @param File $file
+	 * @return bool
+	 */
+	public function isExpensiveToThumbnail( $file ) {
+		return false;
+	}
+
+	/**
+	 * Returns whether or not this handler supports the chained generation of thumbnails according
+	 * to buckets
+	 * @return bool
+	 * @since 1.24
+	 */
+	public function supportsBucketing() {
+		return false;
+	}
+
+	/**
+	 * Returns a normalised params array for which parameters have been cleaned up for bucketing
+	 * purposes
+	 * @param array $params
+	 * @return array
+	 */
+	public function sanitizeParamsForBucketing( $params ) {
+		return $params;
+	}
+
+	/**
+	 * Gets configuration for the file warning message. Return value of
+	 * the following structure:
+	 *   [
+	 *     // Required, module with messages loaded for the client
+	 *     'module' => 'example.filewarning.messages',
+	 *     // Required, array of names of messages
+	 *     'messages' => [
+	 *       // Required, main warning message
+	 *       'main' => 'example-filewarning-main',
+	 *       // Optional, header for warning dialog
+	 *       'header' => 'example-filewarning-header',
+	 *       // Optional, footer for warning dialog
+	 *       'footer' => 'example-filewarning-footer',
+	 *       // Optional, text for more-information link (see below)
+	 *       'info' => 'example-filewarning-info',
+	 *     ],
+	 *     // Optional, link for more information
+	 *     'link' => 'http://example.com',
+	 *   ]
+	 *
+	 * Returns null if no warning is necessary.
+	 * @param File $file
+	 * @return array|null
+	 */
+	public function getWarningConfig( $file ) {
+		return null;
+	}
+
+	/**
+	 * Converts a dimensions array about a potentially multipage document from an
+	 * exhaustive list of ordered page numbers to a list of page ranges
+	 * @param Array $pagesByDimensions
+	 * @return String
+	 * @since 1.30
+	 */
+	public static function getPageRangesByDimensions( $pagesByDimensions ) {
+		$pageRangesByDimensions = [];
+
+		foreach ( $pagesByDimensions as $dimensions => $pageList ) {
+			$ranges = [];
+			$firstPage = $pageList[0];
+			$lastPage = $firstPage - 1;
+
+			foreach ( $pageList as $page ) {
+				if ( $page > $lastPage + 1 ) {
+					if ( $firstPage != $lastPage ) {
+						$ranges[] = "$firstPage-$lastPage";
+					} else {
+						$ranges[] = "$firstPage";
+					}
+
+					$firstPage = $page;
+				}
+
+				$lastPage = $page;
+			}
+
+			if ( $firstPage != $lastPage ) {
+				$ranges[] = "$firstPage-$lastPage";
+			} else {
+				$ranges[] = "$firstPage";
+			}
+
+			$pageRangesByDimensions[ $dimensions ] = $ranges;
+		}
+
+		$dimensionsString = [];
+		foreach ( $pageRangesByDimensions as $dimensions => $pageRanges ) {
+			$dimensionsString[] = "$dimensions:" . implode( ',', $pageRanges );
+		}
+
+		return implode( '/', $dimensionsString );
+	}
+
+	/**
+	 * Get useful response headers for GET/HEAD requests for a file with the given metadata
+	 * @param array $metadata Contains this handler's unserialized getMetadata() for a file
+	 * @return array
+	 * @since 1.30
+	 */
+	public function getContentHeaders( $metadata ) {
+		return [ 'X-Content-Dimensions' => '' ]; // T175689
+	}
+}