php/src/gadgets/render/GadgetRenderer.php

   1 <?php
   2 /**
   3  * Licensed to the Apache Software Foundation (ASF) under one
   4  * or more contributor license agreements.  See the NOTICE file
   5  * distributed with this work for additional information
   6  * regarding copyright ownership.  The ASF licenses this file
   7  * to you under the Apache License, Version 2.0 (the
   8  * "License"); you may not use this file except in compliance
   9  * with the License.  You may obtain a copy of the License at
  10  *
  11  *     http://www.apache.org/licenses/LICENSE-2.0
  12  *
  13  * Unless required by applicable law or agreed to in writing,
  14  * software distributed under the License is distributed on an
  15  * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
  16  * KIND, either express or implied.  See the License for the
  17  * specific language governing permissions and limitations
  18  * under the License.
  19  */
  20
  21 abstract class GadgetRenderer {
  22   protected $context;
  23
  24   public function __construct(GadgetContext $context) {
  25     $this->context = $context;
  26   }
  27
  28   /**
  29    * generates the library string (core:caja:etc.js) including a checksum of all the
  30    * javascript content (?v=<md5 of js>) for cache busting
  31    *
  32    * @param string $libs
  33    * @param Gadget $gadget
  34    * @return string the list of libraries in core:caja:etc.js?v=checksum> format
  35    */
  36   protected function getJsUrl($features) {
  37     $ret = '';
  38     if (! is_array($features) || ! count($features)) {
  39       $ret = 'core';
  40     } else {
  41       $ret = implode(':', $features);
  42     }
  43     $cache = Cache::createCache(Config::get('feature_cache'), 'FeatureCache');
  44     if (($md5 = $cache->get(md5('getJsUrlMD5'))) === false) {
  45       $registry = $this->context->getRegistry();
  46       $features = $registry->features;
  47
  48       // Build a version string from the md5() checksum of all included javascript
  49       // to ensure the client always has the right version
  50       $inlineJs = '';
  51       foreach ($features as $feature => $content) {
  52         $inlineJs .= $registry->getFeatureContent($feature, $this->context, true);
  53       }
  54       $md5 = md5($inlineJs);
  55       $cache->set(md5('getJsUrlMD5'), $md5);
  56     }
  57     $ret .= ".js?v=" . $md5;
  58     return $ret;
  59   }
  60
  61   abstract function renderGadget(Gadget $gadget, $view);
  62 }