Make thumb_handler.php use MediaHandler::parseParamString

Use MediaHandler::parseParamString to parse the parameter string
of a thumbnail. This seems to make much more sense given the
design of the Handler class. Also mark ExtractThumbParameters hook
as deprecated.

This should be reviewed by someone familar with the 404 thumbnailing
infrastructure. I'm unclear if there was a reason for why it wasn't
using MediaHandler::parseParamString in the first place.

Bug: 49629
Change-Id: I43a0e7d6f0e45536e4e24b72140157791f5f027f

diff --git a/RELEASE-NOTES-1.22 b/RELEASE-NOTES-1.22
index 3112e26..d3ce054 100644 (file)
--- a/RELEASE-NOTES-1.22
+++ b/RELEASE-NOTES-1.22
@@ -455,6 +455,8 @@ changes to languages because of Bugzilla reports.
   The skins/common/wikiprintable.css file no longer exists. Return value of
   Skin#commonPrintStylesheet is ignored. Please use the 'mediawiki.legacy.commonPrint'
   module instead or base your skin on SkinTemplate.
+* (bug 49629) The hook ExtractThumbParamaters has been deprecated in favour
+  of media handler overriding MediaHandler::parseParamString.
 
 == Compatibility ==
 

diff --git a/docs/hooks.txt b/docs/hooks.txt
index 5d6a6e4..1723daa 100644 (file)
--- a/docs/hooks.txt
+++ b/docs/hooks.txt
@@ -1077,6 +1077,7 @@ change the tables headers.
 
 'ExtractThumbParameters': Called when extracting thumbnail parameters from a
 thumbnail file name.
+DEPRECATED: Media handler should override MediaHandler::parseParamString instead.
 $thumbname: the base name of the thumbnail file
 &$params: the currently extracted params (has source name, temp or archived zone)
 

diff --git a/includes/media/MediaHandler.php b/includes/media/MediaHandler.php
index 2e8d41d..33b9303 100644 (file)
--- a/includes/media/MediaHandler.php
+++ b/includes/media/MediaHandler.php
@@ -79,13 +79,15 @@ abstract class MediaHandler {
         * Merge a parameter array into a string appropriate for inclusion in filenames
         *
         * @param $params array Array of parameters that have been through normaliseParams.
+        * @return String
         */
        abstract function makeParamString( $params );
 
        /**
         * Parse a param string made with makeParamString back into an array
         *
-        * @param $str string
+        * @param $str string The parameter string without file name (e.g. 122px)
+        * @return Array|Boolean Array of parameters or false on failure.
         */
        abstract function parseParamString( $str );
 

diff --git a/thumb.php b/thumb.php
index 2cda344..bb9c4d6 100644 (file)
--- a/thumb.php
+++ b/thumb.php
@@ -76,7 +76,7 @@ function wfThumbHandle404() {
                return;
        }
 
-       $params = wfExtractThumbParams( $matches['title'] ); // basic wiki URL param extracting
+       $params = wfExtractThumbRequestInfo( $matches['title'] ); // basic wiki URL param extracting
        if ( $params == null ) {
                wfThumbError( 400, 'The specified thumbnail parameters are not recognized.' );
                return;
@@ -88,7 +88,14 @@ function wfThumbHandle404() {
 /**
  * Stream a thumbnail specified by parameters
  *
- * @param $params Array
+ * @param $params Array 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 ) {
@@ -99,17 +106,6 @@ function wfStreamThumb( array $params ) {
        $headers = array(); // HTTP headers to send
 
        $fileName = isset( $params['f'] ) ? $params['f'] : '';
-       unset( $params['f'] );
-
-       // Backwards compatibility parameters
-       if ( isset( $params['w'] ) ) {
-               $params['width'] = $params['w'];
-               unset( $params['w'] );
-       }
-       if ( isset( $params['p'] ) ) {
-               $params['page'] = $params['p'];
-       }
-       unset( $params['r'] ); // ignore 'r' because we unconditionally pass File::RENDER
 
        // Is this a thumb of an archived file?
        $isOld = ( isset( $params['archived'] ) && $params['archived'] );
@@ -166,6 +162,16 @@ function wfStreamThumb( array $params ) {
                $varyHeader[] = 'Cookie';
        }
 
+       // 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;
@@ -229,6 +235,18 @@ function wfStreamThumb( array $params ) {
                }
        }
 
+       // Backwards compatibility parameters
+       if ( isset( $params['w'] ) ) {
+               $params['width'] = $params['w'];
+               unset( $params['w'] );
+       }
+       if ( isset( $params['p'] ) ) {
+               $params['page'] = $params['p'];
+       }
+       unset( $params['r'] ); // ignore 'r' because we unconditionally pass File::RENDER
+       unset( $params['f'] ); // We're done with 'f' parameter.
+
+
        // Get the normalized thumbnail name from the parameters...
        try {
                $thumbName = $img->thumbName( $params );
@@ -317,13 +335,25 @@ function wfStreamThumb( array $params ) {
 }
 
 /**
- * Extract the required params for thumb.php from the thumbnail request URI.
- * At least 'width' and 'f' should be set if the result is an array.
+ * 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 $thumbRel String Thumbnail path relative to the thumb zone
  * @return Array|null associative params array or null
  */
-function wfExtractThumbParams( $thumbRel ) {
+function wfExtractThumbRequestInfo( $thumbRel ) {
        $repo = RepoGroup::singleton()->getLocalRepo();
 
        $hashDirReg = $subdirReg = '';
@@ -349,12 +379,59 @@ function wfExtractThumbParams( $thumbRel ) {
                $params['temp'] = 1;
        }
 
-       // Check hooks if parameters can be extracted
-       // Hooks return false if they manage to *resolve* the parameters
+       $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 $param Array Array of parameters so far.
+ * @return Array parameters array with more parameters.
+ */
+function wfExtractThumbParams( $file, $params ) {
+       if ( !isset( $params['thumbName'] ) ) {
+               throw new MWException( "No thumbnail name passed to wfExtractThumbParams" );
+       }
+
+       $thumbname = $params['thumbName'];
+       unset( $params['thumbName'] );
+
+       // Do the hook first for older extensions that rely on it.
        if ( !wfRunHooks( 'ExtractThumbParameters', array( $thumbname, &$params ) ) ) {
+               // Check hooks if parameters can be extracted
+               // Hooks return false if they manage to *resolve* the parameters
+               // This hook should be considered deprecated
+               wfDeprecated( 'ExtractThumbParameters', '1.22' );
                return $params; // valid thumbnail URL (via extension or config)
-       // Check if the parameters can be extracted from the thumbnail name...
-       } elseif ( preg_match( '!^(page(\d*)-)*(\d*)px-[^/]*$!', $thumbname, $matches ) ) {
+       }
+
+       // 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 ( $handler !== 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 ) {
@@ -362,8 +439,7 @@ function wfExtractThumbParams( $thumbRel ) {
                }
                return $params; // valid thumbnail URL
        }
-
-       return null; // not a valid thumbnail URL
+       return null;
 }
 
 /**