Added support for aggregating and caching library assets

h5p-default-storage.class.php

@@ -148,6 +148,104 @@ class DefaultStorage implements \H5P\FileStorage {
     }
   }
 
+  /**
+   * Will concatenate all JavaScrips and Stylesheets into two files in order
+   * to improve page performance.
+   *
+   * @param array $files
+   *  A set of all the assets required for content to display
+   * @param string $key
+   *  Hashed key for cached asset
+   */
+  public function cacheAssets(&$files, $key) {
+    foreach ($files as $type => $assets) {
+      $content = '';
+
+      foreach ($assets as $asset) {
+        // Get content from asset file
+        $assetContent = file_get_contents($this->path . $asset->path);
+        $cssRelPath = preg_replace('/[^\/]+$/', '', $asset->path);
+
+        // Get file content and concatenate
+        if ($type === 'scripts') {
+          $content .= $assetContent . ";\n";
+        }
+        else {
+          // Rewrite relative URLs used inside stylesheets
+          $content .= preg_replace_callback(
+              '/url\([\'"]?([^"\')]+)[\'"]?\)/i',
+              function ($matches) use ($cssRelPath) {
+                return substr($matches[1], 0, 3) !== '../' ? $matches[0] : 'url("../' . $cssRelPath . $matches[1] . '")';
+              },
+              $assetContent
+          ) . "\n";
+        }
+      }
+
+      self::dirReady("{$this->path}/cachedassets");
+      $ext = ($type === 'scripts' ? 'js' : 'css');
+      file_put_contents("{$this->path}/cachedassets/{$key}.{$ext}", $content);
+    }
+
+    // Use the newly created cache
+    $files = self::formatCachedAssets($key);
+  }
+
+  /**
+   * Will check if there are cache assets available for content.
+   *
+   * @param string $key
+   *  Hashed key for cached asset
+   * @return array
+   */
+  public function getCachedAssets($key) {
+    if (!file_exists("{$this->path}/cachedassets/{$key}.js") ||
+        !file_exists("{$this->path}/cachedassets/{$key}.css") {
+      return NULL;
+    }
+    return self::formatCachedAssets($key);
+  }
+
+  /**
+   * Remove the aggregated cache files.
+   *
+   * @param array $keys
+   *   The hash keys of removed files
+   */
+  public function deleteCachedAssets($keys) {
+    $context = \context_system::instance();
+    $fs = get_file_storage();
+
+    foreach ($keys as $hash) {
+      foreach (array('js', 'css') as $ext) {
+        $path = "{$this->path}/cachedassets/{$key}.{$ext}";
+        if (file_exists($path)) {
+          unlink($path);
+        }
+      }
+    }
+  }
+
+  /**
+   * Format the cached assets data the way it's supposed to be.
+   *
+   * @param string $key
+   *  Hashed key for cached asset
+   * @return array
+   */
+  private static function formatCachedAssets($key) {
+    return array(
+      'scripts' => array((object) array(
+        'path' => "/cachedassets/{$key}.js",
+        'version' => ''
+      )),
+      'styles' => array((object) array(
+        'path' => "/cachedassets/{$key}.css",
+        'version' => ''
+      ))
+    );
+  }
+
   /**
    * Recursive function for copying directories.
    *

h5p-file-storage.interface.php

@@ -91,4 +91,32 @@ interface FileStorage {
    * @param string $filename
    */
   public function deleteExport($filename);
+
+  /**
+   * Will concatenate all JavaScrips and Stylesheets into two files in order
+   * to improve page performance.
+   *
+   * @param array $files
+   *  A set of all the assets required for content to display
+   * @param string $key
+   *  Hashed key for cached asset
+   */
+  public function cacheAssets(&$files, $key);
+
+  /**
+   * Will check if there are cache assets available for content.
+   *
+   * @param string $key
+   *  Hashed key for cached asset
+   * @return array
+   */
+  public function getCachedAssets($key);
+
+  /**
+   * Remove the aggregated cache files.
+   *
+   * @param array $keys
+   *   The hash keys of removed files
+   */
+  public function deleteCachedAssets($keys);
 }

h5p.classes.php

@@ -536,6 +536,29 @@ interface H5PFrameworkInterface {
    * @return boolean
    */
   public function isContentSlugAvailable($slug);
+
+  /**
+   * Stores hash keys for cached assets, aggregated JavaScripts and
+   * stylesheets, and connects it to libraries so that we know which cache file
+   * to delete when a library is updated.
+   *
+   * @param string $key
+   *  Hash key for the given libraries
+   * @param array $libraries
+   *  List of dependencies(libraries) used to create the key
+   */
+  public function saveCachedAssets($key, $libraries);
+
+  /**
+   * Locate hash keys for given library and delete them.
+   * Used when cache file are deleted.
+   *
+   * @param int $library_id
+   *  Library identifier
+   * @return array
+   *  List of hash keys removed
+   */
+  public function deleteCachedAssets($library_id);
 }
 
 /**
@@ -1345,6 +1368,12 @@ class H5PStorage {
       // Save library folder
       $this->h5pC->fs->saveLibrary($library);
 
+      // Remove cachedassets that uses this library
+      if ($this->h5pC->aggregateAssets && isset($library['libraryId'])) {
+        $removedKeys = $this->h5pF->deleteCachedAssets($library['libraryId']);
+        $this->h5pC->fs->deleteCachedAssets($removedKeys);
+      }
+
       // Remove tmp folder
       H5PCore::deleteFileTree($library['uploadDirectory']);
 
@@ -1680,6 +1709,8 @@ class H5PCore {
     $this->exportEnabled = $export;
     $this->development_mode = $development_mode;
 
+    $this->aggregateAssets = FALSE; // Off by default.. for now
+
     if ($development_mode & H5PDevelopment::MODE_LIBRARY) {
       $this->h5pD = new H5PDevelopment($this->h5pF, $path . '/', $language);
     }
@@ -1909,9 +1940,7 @@ class H5PCore {
    * @return array files.
    */
   public function getDependenciesFiles($dependencies, $prefix = '') {
-    $aggregateAssets = TRUE;
+    if ($this->aggregateAssets) {
-
-    if ($aggregateAssets) {
       // Get aggregated files for assets
       $key = self::getDependenciesHash($dependencies);
 
@@ -1938,11 +1967,12 @@ class H5PCore {
       $this->getDependencyAssets($dependency, 'preloadedCss', $files['styles'], $prefix);
     }
 
-    if ($aggregateAssets) {
+    if ($this->aggregateAssets) {
       // Aggregate and store assets
       $this->fs->cacheAssets($files, $key);
 
-      // TODO: Update cache table
+      // Keep track of which libraries have been cached in case they are updated
+      $this->h5pF->saveCachedAssets($key, $dependencies);
     }
 
     return $files;