php/src/gadgets/GadgetFactory.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 /**
  22  * The Gadget Factory builds a gadget based on the current context and token and returns a fully processed
  23  * gadget ready to be rendered.
  24  *
  25  */
  26 class GadgetFactory {
  27   /**
  28    * @var GadgetContext
  29    */
  30   private $context;
  31   private $token;
  32
  33   public function __construct(GadgetContext $context, $token) {
  34     $this->context = $context;
  35     $this->token = $token;
  36   }
  37
  38   /**
  39    * Returns the processed gadget spec
  40    *
  41    * @return GadgetSpec
  42    */
  43   public function createGadget() {
  44     $gadgetUrl = $this->context->getUrl();
  45     if ($this->context->getBlacklist() != null && $this->context->getBlacklist()->isBlacklisted($gadgetUrl)) {
  46       throw new GadgetException("The Gadget ($gadgetUrl) is blacklisted and can not be rendered");
  47     }
  48     // Fetch the gadget's content and create a GadgetSpec
  49     $gadgetContent = $this->fetchGadget($gadgetUrl);
  50     $gadgetSpecParser = new GadgetSpecParser();
  51     $gadgetSpec = $gadgetSpecParser->parse($gadgetContent);
  52     $gadget = new Gadget($gadgetSpec, $this->context);
  53
  54     // Process the gadget: fetching remote resources, processing & applying the correct translations, user prefs and feature resolving
  55     $this->fetchResources($gadget);
  56     $this->mergeLocales($gadget);
  57     $this->parseUserPrefs($gadget);
  58     $this->addSubstitutions($gadget);
  59     $this->applySubstitutions($gadget);
  60     $this->parseFeatures($gadget);
  61     return $gadget;
  62   }
  63
  64   /**
  65    * Resolves the Required and Optional features and their dependencies into a real feature list using
  66    * the GadgetFeatureRegistry, which can be used to construct the javascript for the gadget
  67    *
  68    * @param Gadget $gadget
  69    */
  70   private function parseFeatures(Gadget &$gadget) {
  71     $found = $missing = array();
  72     if (!$this->context->getRegistry()->resolveFeatures(array_merge($gadget->gadgetSpec->requiredFeatures, $gadget->gadgetSpec->optionalFeatures), $found, $missing)) {
  73       $requiredMissing = false;
  74       foreach ($missing as $featureName) {
  75         if (in_array($featureName, $gadget->gadgetSpec->requiredFeatures)) {
  76           $requiredMissing = true;
  77           break;
  78         }
  79       }
  80       if ($requiredMissing) {
  81         throw new GadgetException("Unknown features: ".implode(',', $missing));
  82       }
  83     }
  84     unset($gadget->gadgetSpec->optionalFeatures);
  85     unset($gadget->gadgetSpec->requiredFeatures);
  86     $gadget->features = $found;
  87   }
  88
  89   /**
  90    * Applies the substitutions to the complex types (preloads, user prefs, etc). Simple
  91    * types (author, title, etc) are translated on the fly in the gadget's getFoo() functions
  92    */
  93   private function applySubstitutions(Gadget &$gadget) {
  94     // Apply the substitutions to the UserPrefs
  95     foreach ($gadget->gadgetSpec->userPrefs as $key => $pref) {
  96       $gadget->gadgetSpec->userPrefs[$key]['name'] = $gadget->substitutions->substitute($pref['name']);
  97       $gadget->gadgetSpec->userPrefs[$key]['displayName'] = $gadget->substitutions->substitute($pref['displayName']);
  98       $gadget->gadgetSpec->userPrefs[$key]['required'] = $gadget->substitutions->substitute($pref['required']);
  99       $gadget->gadgetSpec->userPrefs[$key]['datatype'] = $gadget->substitutions->substitute($pref['datatype']);
 100       $gadget->gadgetSpec->userPrefs[$key]['defaultValue'] = $gadget->substitutions->substitute($pref['defaultValue']);
 101       $gadget->gadgetSpec->userPrefs[$key]['value'] = $gadget->substitutions->substitute($pref['value']);
 102       if (isset($pref['enumValues'])) {
 103         foreach ($pref['enumValues'] as $enumKey => $enumVal) {
 104           $gadget->gadgetSpec->userPrefs[$key]['enumValues'][$enumKey]['value'] = $gadget->substitutions->substitute($enumVal['value']);
 105           $gadget->gadgetSpec->userPrefs[$key]['enumValues'][$enumKey]['displayValue'] = $gadget->substitutions->substitute($enumVal['displayValue']);
 106         }
 107       }
 108     }
 109     // Apply substitutions to the preloads
 110     foreach ($gadget->gadgetSpec->preloads as $url => $preload) {
 111       $gadget->gadgetSpec->preloads[$url]['body'] = $gadget->substitutions->substitute($preload['body']);
 112     }
 113   }
 114
 115   /**
 116    * Seeds the substitutions class with the user prefs, messages, bidi and module id
 117    */
 118   private function addSubstitutions(Gadget &$gadget) {
 119     $gadget->substitutions = new Substitutions();
 120     if ($this->token) {
 121       $gadget->substitutions->addSubstitution('MODULE', "ID", $this->token->getModuleId());
 122     } else {
 123       $gadget->substitutions->addSubstitution('MODULE', "ID", 0);
 124     }
 125     if ($gadget->gadgetSpec->locales) {
 126       $gadget->substitutions->addSubstitutions('MSG', $gadget->gadgetSpec->locales);
 127     }
 128     $gadget->substitutions->addSubstitution('BIDI', "START_EDGE", $gadget->rightToLeft ? "right" : "left");
 129     $gadget->substitutions->addSubstitution('BIDI', "END_EDGE", $gadget->rightToLeft ? "left" : "right");
 130     $gadget->substitutions->addSubstitution('BIDI', "DIR", $gadget->rightToLeft ? "rtl" : "ltr");
 131     $gadget->substitutions->addSubstitution('BIDI', "REVERSE_DIR", $gadget->rightToLeft ? "ltr" : "rtl");
 132     foreach ($gadget->gadgetSpec->userPrefs as $pref) {
 133       $gadget->substitutions->addSubstitution('UP', $gadget->substitutions->substitute($pref['name']), $gadget->substitutions->substitute($pref['value']));
 134     }
 135   }
 136   /**
 137    * Process the UserPrefs values based on the current context
 138    *
 139    * @param Gadget $gadget
 140    */
 141   private function parseUserPrefs(Gadget &$gadget) {
 142     foreach ($gadget->gadgetSpec->userPrefs as $key => $pref) {
 143       $queryKey = 'up_'.$pref['name'];
 144       $gadget->gadgetSpec->userPrefs[$key]['value'] = isset($_GET[$queryKey]) ? trim(urldecode($_GET[$queryKey])) : $pref['defaultValue'];
 145     }
 146   }
 147
 148   /**
 149    * Merges all matching Message bundles, with a full match (lang and country) having the
 150    * highest priority and all/all having the lowest.
 151    *
 152    * This distills the locales array's back to one array of translations, which is then exposed
 153    * through the $gadget->substitutions class
 154    *
 155    * @param Gadget $gadget
 156    */
 157   private function mergeLocales(Gadget $gadget) {
 158     if (count($gadget->gadgetSpec->locales)) {
 159       $contextLocale = $this->context->getLocale();
 160       $locales = $gadget->gadgetSpec->locales;
 161       $gadget->rightToLeft  = false;
 162       $full = $partial = $all = null;
 163       foreach ($locales as $locale) {
 164         if ($locale['lang'] == $contextLocale['lang'] && $locale['country'] == $contextLocale['country']) {
 165           $full = $locale['messageBundle'];
 166           $gadget->rightToLeft = $locale['languageDirection'] == 'rtl';
 167         } elseif ($locale['lang'] == $contextLocale['lang'] && $locale['country'] == 'all') {
 168           $partial = $locale['messageBundle'];
 169         } elseif ($locale['country'] == 'all' && $locale['lang'] == 'all') {
 170           $all = $locale['messageBundle'];
 171         }
 172       }
 173       $gadget->gadgetSpec->locales = array();
 174       // array_merge overwrites duplicate keys from param 2 over param 1, so $full takes precedence over partial, and it over all
 175       if ($full) $gadget->gadgetSpec->locales = array_merge($full, $gadget->gadgetSpec->locales);
 176       if ($partial) $gadget->gadgetSpec->locales = array_merge($partial, $gadget->gadgetSpec->locales);
 177       if ($all) $gadget->gadgetSpec->locales = array_merge($all, $gadget->gadgetSpec->locales);
 178     }
 179   }
 180
 181   /**
 182    * Fetches all remote resources simultaniously using a multiFetchRequest to optimize rendering time.
 183    *
 184    * The preloads will be json_encoded to their gadget document injection format, and the locales will
 185    * be reduced to only the GadgetContext->getLocale matching entries.
 186    *
 187    * @param Gadget $gadget
 188    * @param GadgetContext $context
 189    */
 190   private function fetchResources(Gadget &$gadget) {
 191     $contextLocale = $this->context->getLocale();
 192     $unsignedRequests = $signedRequests = array();
 193     foreach ($gadget->getLocales() as $key => $locale) {
 194       // Only fetch the locales that match the current context's language and country
 195       if (($locale['country'] == 'all' && $locale['lang'] == 'all') || ($locale['lang'] == $contextLocale['lang'] && $locale['country'] == 'all') || ($locale['lang'] == $contextLocale['lang'] && $locale['country'] == $contextLocale['country'])) {
 196         if (!empty($locale['messages'])) {
 197           // locale matches the current context, add it to the requests queue
 198           $unsignedRequests[] = $locale['messages'];
 199         }
 200       } else {
 201         // remove any locales that are not applicable to this context
 202         unset($gadget->gadgetSpec->locales[$key]);
 203       }
 204     }
 205     // Add preloads to the request queue
 206     foreach ($gadget->getPreloads() as $preload) {
 207       if (!empty($preload['href'])) {
 208         if (!empty($preload['authz']) && $preload['authz'] == 'SIGNED') {
 209           if ($this->token == '') {
 210             throw new GadgetException("Signed preloading requested, but no valid security token set");
 211           }
 212           $signedRequests[] = $preload['href'];
 213         } else {
 214           $unsignedRequests[] = $preload['href'];
 215         }
 216       }
 217     }
 218     // Perform the non-signed requests
 219     foreach ($unsignedRequests as $key => $requestUrl) {
 220       $request = new RemoteContentRequest($requestUrl);
 221       $request->createRemoteContentRequestWithUri($requestUrl);
 222       $request->getOptions()->ignoreCache = $this->context->getIgnoreCache();
 223       $unsignedRequests[$key] = $request;
 224     }
 225     $responses = array();
 226     if (count($unsignedRequests)) {
 227       $brc = new BasicRemoteContent();
 228       $resps = $brc->multiFetch($unsignedRequests);
 229       foreach ($resps as $response) {
 230         $responses[$response->getUrl()] = array(
 231             'body' => $response->getResponseContent(),
 232             'rc' => $response->getHttpCode());
 233       }
 234     }
 235     // Perform the signed requests
 236     foreach ($signedRequests as $key => $requestUrl) {
 237       $request = new RemoteContentRequest($requestUrl);
 238       $request->setAuthType(RemoteContentRequest::$AUTH_SIGNED);
 239       $request->setNotSignedUri($requestUrl);
 240       $request->getOptions()->ignoreCache = $this->context->getIgnoreCache();
 241       $signedRequests[$key] = $request;
 242     }
 243     if (count($signedRequests)) {
 244       $remoteContent = new BasicRemoteContent(new BasicRemoteContentFetcher(), $signingFetcherFactory);
 245       $resps = $remoteContent->multiFetch($signedRequests);
 246       foreach ($resps as $response) {
 247         $responses[$response->getNotSignedUrl()] = array(
 248             'body' => $response->getResponseContent(),
 249             'rc' => $response->getHttpCode());
 250       }
 251     }
 252     // assign the results to the gadget locales and preloads (using the url as the key)
 253     foreach ($gadget->gadgetSpec->locales as $key => $locale) {
 254       if (!empty($locale['messages']) && isset($responses[$locale['messages']]) && $responses[$locale['messages']]['rc'] == 200) {
 255         $gadget->gadgetSpec->locales[$key]['messageBundle'] = $this->parseMessageBundle($responses[$locale['messages']]['body']);
 256       }
 257     }
 258     $preloads = array();
 259     foreach ($gadget->gadgetSpec->preloads as $key => $preload) {
 260       if (!empty($preload['href']) && isset($responses[$preload['href']]) && $responses[$preload['href']]['rc'] == 200) {
 261         $preloads[$preload['href']] = $responses[$preload['href']];
 262       }
 263     }
 264     $gadget->gadgetSpec->preloads = $preloads;
 265   }
 266
 267   /**
 268    * Parses the (remote / fetched) message bundle xml
 269    *
 270    * @param string $messageBundleData
 271    * @return array (MessageBundle)
 272    */
 273   private function parseMessageBundle($messageBundleData) {
 274     libxml_use_internal_errors(true);
 275     $doc = new DOMDocument();
 276     if (! $doc->loadXML($messageBundleData, LIBXML_NOCDATA)) {
 277       throw new GadgetSpecException("Error parsing gadget xml:\n".XmlError::getErrors($messageBundleData));
 278     }
 279     $messageBundle = array();
 280     if (($messageBundleNode = $doc->getElementsByTagName('messagebundle')) != null && $messageBundleNode->length > 0) {
 281       $messageBundleNode = $messageBundleNode->item(0);
 282       $messages = $messageBundleNode->getElementsByTagName('msg');
 283       foreach ($messages as $msg) {
 284         $messageBundle[$msg->getAttribute('name')] = trim($msg->nodeValue);
 285       }
 286     }
 287     return $messageBundle;
 288   }
 289
 290   /**
 291    * Fetches the gadget xml for the requested URL using the http fetcher
 292    *
 293    * @param unknown_type $gadgetUrl
 294    * @return string gadget's xml content
 295    */
 296   protected function fetchGadget($gadgetUrl) {
 297     $request = new RemoteContentRequest($gadgetUrl);
 298     $request->setToken($this->token);
 299     $request->getOptions()->ignoreCache = $this->context->getIgnoreCache();
 300     $xml = $this->context->getHttpFetcher()->fetch($request);
 301     if ($xml->getHttpCode() != '200') {
 302       throw new GadgetException("Failed to retrieve gadget content (recieved http code " . $xml->getHttpCode() . ")");
 303     }
 304     return $xml->getResponseContent();
 305   }
 306 }