Refactor CSS and JS caching

  * Increase HTTP cache time since the resources are timestamped on request
    anyway
  * Check userscript.js only once for JS cache validation
  * Use cache class

3 files changed, 70 insertions, 117 deletions

diff --git a/inc/httputils.php b/inc/httputils.php
index 8da42e3b7..0ad97a9a1 100644
--- a/inc/httputils.php
+++ b/inc/httputils.php
@@ -197,3 +197,55 @@ function http_gzip_valid($uncompressed_file) {
 
     return true;
 }
+
+/**
+ * Set HTTP headers and echo cachefile, if useable
+ *
+ * This function handles output of cacheable resource files. It ses the needed
+ * HTTP headers. If a useable cache is present, it is passed to the web server
+ * and the scrpt is terminated.
+ */
+function http_cached($cache, $cache_ok) {
+    global $conf;
+
+    // check cache age & handle conditional request
+    // since the resource files are timestamped, we can use a long max age: 1 year
+    header('Cache-Control: public, max-age=31536000');
+    header('Pragma: public');
+    if($cache_ok){
+        http_conditionalRequest(filemtime($cache));
+        if($conf['allowdebug']) header("X-CacheUsed: $cache");
+
+        // finally send output
+        if ($conf['gzip_output'] && http_gzip_valid($cache)) {
+            header('Vary: Accept-Encoding');
+            header('Content-Encoding: gzip');
+            readfile($cache.".gz");
+        } else {
+            if (!http_sendfile($cache)) readfile($cache);
+        }
+        exit;
+    }
+
+    http_conditionalRequest(time());
+}
+
+/**
+ * Cache content and print it
+ */
+function http_cached_finish($file, $content) {
+    global $conf;
+
+    // save cache file
+    io_saveFile($file, $content);
+    if(function_exists('gzopen')) io_saveFile("$file.gz",$content);
+
+    // finally send output
+    if ($conf['gzip_output']) {
+        header('Vary: Accept-Encoding');
+        header('Content-Encoding: gzip');
+        print gzencode($content,9,FORCE_GZIP);
+    } else {
+        print $content;
+    }
+}
diff --git a/lib/exe/css.php b/lib/exe/css.php
index e4105b427..9751b5be4 100644
--- a/lib/exe/css.php
+++ b/lib/exe/css.php
@@ -46,7 +46,7 @@ function css_out(){
     }
 
     // The generated script depends on some dynamic options
-    $cache = getCacheName('styles'.$_SERVER['HTTP_HOST'].$_SERVER['SERVER_PORT'].DOKU_BASE.$tplinc.$mediatype,'.css');
+    $cache = new cache('styles'.$_SERVER['HTTP_HOST'].$_SERVER['SERVER_PORT'].DOKU_BASE.$tplinc.$mediatype,'.css');
 
     // load template styles
     $tplstyles = array();
@@ -87,26 +87,14 @@ function css_out(){
         }
     }
 
-    // check cache age & handle conditional request
-    header('Cache-Control: public, max-age=3600');
-    header('Pragma: public');
-    if(css_cacheok($cache,array_keys($files),$tplinc)){
-        http_conditionalRequest(filemtime($cache));
-        if($conf['allowdebug']) header("X-CacheUsed: $cache");
-
-        // finally send output
-        if ($conf['gzip_output'] && http_gzip_valid($cache)) {
-          header('Vary: Accept-Encoding');
-          header('Content-Encoding: gzip');
-          readfile($cache.".gz");
-        } else {
-          if (!http_sendfile($cache)) readfile($cache);
-        }
+    $cache_files = array_merge(array_keys($files), getConfigFiles('main'));
+    $cache_files[] = $tplinc.'style.ini';
+    $cache_files[] = __FILE__;
 
-        return;
-    } else {
-        http_conditionalRequest(time());
-    }
+    // check cache age & handle conditional request
+    // This may exit if a cache can be used
+    http_cached($cache->cache,
+                $cache->useCache(array('files' => $cache_files)));
 
     // start output buffering and build the stylesheet
     ob_start();
@@ -135,45 +123,7 @@ function css_out(){
         $css = css_compress($css);
     }
 
-    // save cache file
-    io_saveFile($cache,$css);
-    if(function_exists('gzopen')) io_saveFile("$cache.gz",$css);
-
-    // finally send output
-    if ($conf['gzip_output']) {
-      header('Vary: Accept-Encoding');
-      header('Content-Encoding: gzip');
-      print gzencode($css,9,FORCE_GZIP);
-    } else {
-      print $css;
-    }
-}
-
-/**
- * Checks if a CSS Cache file still is valid
- *
- * @author Andreas Gohr <andi@splitbrain.org>
- */
-function css_cacheok($cache,$files,$tplinc){
-    global $config_cascade;
-
-    if(isset($_REQUEST['purge'])) return false; //support purge request
-
-    $ctime = @filemtime($cache);
-    if(!$ctime) return false; //There is no cache
-
-    // some additional files to check
-    $files = array_merge($files, getConfigFiles('main'));
-    $files[] = $tplinc.'style.ini';
-    $files[] = __FILE__;
-
-    // now walk the files
-    foreach($files as $file){
-        if(@filemtime($file) > $ctime){
-            return false;
-        }
-    }
-    return true;
+    http_cached_finish($cache->cache, $css);
 }
 
 /**
diff --git a/lib/exe/js.php b/lib/exe/js.php
index 28894ffc6..0688825c6 100644
--- a/lib/exe/js.php
+++ b/lib/exe/js.php
@@ -32,7 +32,8 @@ function js_out(){
     global $config_cascade;
 
     // The generated script depends on some dynamic options
-    $cache = getCacheName('scripts'.$_SERVER['HTTP_HOST'].$_SERVER['SERVER_PORT'],'.js');
+    $cache = new cache('scripts'.$_SERVER['HTTP_HOST'].$_SERVER['SERVER_PORT'],
+                       '.js');
 
     // load minified version for some files
     $min = $conf['compress'] ? '.min' : '';
@@ -70,25 +71,13 @@ function js_out(){
         $files[] = $config_cascade['userscript']['default'];
     }
 
+    $cache_files = array_merge($files, getConfigFiles('main'));
+    $cache_files[] = __FILE__;
+
     // check cache age & handle conditional request
-    header('Cache-Control: public, max-age=3600');
-    header('Pragma: public');
-    if(js_cacheok($cache,$files)){
-        http_conditionalRequest(filemtime($cache));
-        if($conf['allowdebug']) header("X-CacheUsed: $cache");
-
-        // finally send output
-        if ($conf['gzip_output'] && http_gzip_valid($cache)) {
-            header('Vary: Accept-Encoding');
-            header('Content-Encoding: gzip');
-            readfile($cache.".gz");
-        } else {
-            if (!http_sendfile($cache)) readfile($cache);
-        }
-        return;
-    } else {
-        http_conditionalRequest(time());
-    }
+    // This may exit if a cache can be used
+    http_cached($cache->cache,
+                $cache->useCache(array('files' => $cache_files)));
 
     // start output buffering and build the script
     ob_start();
@@ -137,18 +126,7 @@ function js_out(){
 
     $js .= "\n"; // https://bugzilla.mozilla.org/show_bug.cgi?id=316033
 
-    // save cache file
-    io_saveFile($cache,$js);
-    if(function_exists('gzopen')) io_saveFile("$cache.gz",$js);
-
-    // finally send output
-    if ($conf['gzip_output']) {
-        header('Vary: Accept-Encoding');
-        header('Content-Encoding: gzip');
-        print gzencode($js,9,FORCE_GZIP);
-    } else {
-        print $js;
-    }
+    http_cached_finish($cache->cache, $js);
 }
 
 /**
@@ -184,33 +162,6 @@ function js_load($file){
 }
 
 /**
- * Checks if a JavaScript Cache file still is valid
- *
- * @author Andreas Gohr <andi@splitbrain.org>
- */
-function js_cacheok($cache,$files){
-    if(isset($_REQUEST['purge'])) return false; //support purge request
-
-    $ctime = @filemtime($cache);
-    if(!$ctime) return false; //There is no cache
-
-    global $config_cascade;
-
-    // some additional files to check
-    $files = array_merge($files, getConfigFiles('main'));
-    $files[] = $config_cascade['userscript']['default'];
-    $files[] = __FILE__;
-
-    // now walk the files
-    foreach($files as $file){
-        if(@filemtime($file) > $ctime){
-            return false;
-        }
-    }
-    return true;
-}
-
-/**
  * Returns a list of possible Plugin Scripts (no existance check here)
  *
  * @author Andreas Gohr <andi@splitbrain.org>