Centralise url handling for urls to static resources

[lhc/web/wiklou.git] / includes / OutputPage.php

diff --git a/includes/OutputPage.php b/includes/OutputPage.php
index 6a56848..e06fad9 100644 (file)
--- a/includes/OutputPage.php
+++ b/includes/OutputPage.php
@@ -229,9 +229,6 @@ class OutputPage extends ContextSource {
        /** @var string */
        private $mPageTitleActionText = '';
 
-       /** @var array */
-       private $mParseWarnings = array();
-
        /** @var int Cache stuff. Looks like mEnableClientCache */
        protected $mCdnMaxage = 0;
        /** @var int Upper limit on mCdnMaxage */
@@ -1773,7 +1770,6 @@ class OutputPage extends ContextSource {
                $this->mNewSectionLink = $parserOutput->getNewSection();
                $this->mHideNewSectionLink = $parserOutput->getHideNewSection();
 
-               $this->mParseWarnings = $parserOutput->getWarnings();
                if ( !$parserOutput->isCacheable() ) {
                        $this->enableClientCache( false );
                }
@@ -3813,6 +3809,58 @@ class OutputPage extends ContextSource {
                return $link;
        }
 
+       /**
+        * Transform path to web-accessible static resource.
+        *
+        * This is used to add a validation hash as query string.
+        * This aids various behaviors:
+        *
+        * - Put long Cache-Control max-age headers on responses for improved
+        *   cache performance.
+        * - Get the correct version of a file as expected by the current page.
+        * - Instantly get the updated version of a file after deployment.
+        *
+        * Avoid using this for urls included in HTML as otherwise clients may get different
+        * versions of a resource when navigating the site depending on when the page was cached.
+        * If changes to the url propagate, this is not a problem (e.g. if the url is in
+        * an external stylesheet).
+        *
+        * @since 1.27
+        * @param Config $config
+        * @param string $path Path-absolute URL to file (from document root, must start with "/")
+        * @return string URL
+        */
+       public static function transformResourcePath( Config $config, $path ) {
+               global $IP;
+               $remotePath = $config->get( 'ResourceBasePath' );
+               if ( strpos( $path, $remotePath ) !== 0 ) {
+                       // Path is outside wgResourceBasePath, ignore.
+                       return $path;
+               }
+               $path = RelPath\getRelativePath( $path, $remotePath );
+               return self::transformFilePath( $remotePath, $IP, $path );
+       }
+
+       /**
+        * Utility method for transformResourceFilePath().
+        *
+        * Caller is responsible for ensuring the file exists. Emits a PHP warning otherwise.
+        *
+        * @since 1.27
+        * @param string $remotePath URL path that points to $localPath
+        * @param string $localPath File directory exposed at $remotePath
+        * @param string $file Path to target file relative to $localPath
+        * @return string URL
+        */
+       public static function transformFilePath( $remotePath, $localPath, $file ) {
+               $hash = md5_file( "$localPath/$file" );
+               if ( $hash === false ) {
+                       wfLogWarning( __METHOD__ . ": Failed to hash $localPath/$file" );
+                       $hash = '';
+               }
+               return "$remotePath/$file?" . substr( $hash, 0, 5 );
+       }
+
        /**
         * Transform "media" attribute based on request parameters
         *