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   private $context;
  28   private $token;
  29
  30   public function __construct(GadgetContext $context, $token) {
  31     $this->context = $context;
  32     $this->token = $token;
  33   }
  34
  35   /**
  36    * Returns the processed gadget spec
  37    *
  38    * @return GadgetSpec
  39    */
  40   public function createGadget() {
  41     $gadgetUrl = $this->context->getUrl();
  42     if ($this->context->getBlacklist() != null && $this->context->getBlacklist()->isBlacklisted($gadgetUrl)) {
  43       throw new GadgetException("The Gadget ($gadgetUrl) is blacklisted and can not be rendered");
  44     }
  45     // Fetch the gadget's content and create a GadgetSpec
  46     $gadgetContent = $this->fetchGadget($gadgetUrl);
  47     $gadgetSpecParser = new GadgetSpecParser();
  48     $gadgetSpec = $gadgetSpecParser->parse($gadgetContent);
  49     $gadget = new Gadget($gadgetSpec, $this->context);
  50
  51     // Process the gadget: fetching remote resources, processing & applying the correct translations, user prefs and feature resolving
  52     $this->fetchResources($gadget);
  53     $this->mergeLocales($gadget);
  54     $this->parseUserPrefs($gadget);
  55     $this->addSubstitutions($gadget);
  56     $this->applySubstitutions($gadget);
  57     $this->parseFeatures($gadget);
  58     return $gadget;
  59   }
  60
  61   /**
  62    * Resolves the Required and Optional features and their dependencies into a real feature list using
  63    * the GadgetFeatureRegistry, which can be used to construct the javascript for the gadget
  64    *
  65    * @param Gadget $gadget
  66    */
  67   private function parseFeatures(Gadget &$gadget) {
  68     $found = $missing = array();
  69     if (!$this->context->getRegistry()->resolveFeatures(array_merge($gadget->gadgetSpec->requiredFeatures, $gadget->gadgetSpec->optionalFeatures), $found, $missing)) {
  70       $requiredMissing = false;
  71       foreach ($missing as $featureName) {
  72         if (in_array($featureName, $gadget->gadgetSpec->requiredFeatures)) {
  73           $requiredMissing = true;
  74           break;
  75         }
  76       }
  77       if ($requiredMissing) {
  78         throw new GadgetException("Unknown features: ".implode(',', $missing));
  79       }
  80     }
  81     unset($gadget->gadgetSpec->optionalFeatures);
  82     unset($gadget->gadgetSpec->requiredFeatures);
  83     $gadget->features = $found;
  84   }
  85
  86   /**
  87    * Applies the substitutions to the complex types (preloads, user prefs, etc). Simple
  88    * types (author, title, etc) are translated on the fly in the gadget's getFoo() functions
  89    */
  90   private function applySubstitutions(Gadget &$gadget) {
  91     // Apply the substitutions to the UserPrefs
  92     foreach ($gadget->gadgetSpec->userPrefs as $key => $pref) {
  93       $gadget->gadgetSpec->userPrefs[$key]['name'] = $gadget->substitutions->substitute($pref['name']);
  94       $gadget->gadgetSpec->userPrefs[$key]['displayName'] = $gadget->substitutions->substitute($pref['displayName']);
  95       $gadget->gadgetSpec->userPrefs[$key]['required'] = $gadget->substitutions->substitute($pref['required']);
  96       $gadget->gadgetSpec->userPrefs[$key]['datatype'] = $gadget->substitutions->substitute($pref['datatype']);
  97       $gadget->gadgetSpec->userPrefs[$key]['defaultValue'] = $gadget->substitutions->substitute($pref['defaultValue']);
  98       $gadget->gadgetSpec->userPrefs[$key]['value'] = $gadget->substitutions->substitute($pref['value']);
  99       if (isset($pref['enumValues'])) {
 100         foreach ($pref['enumValues'] as $enumKey => $enumVal) {
 101           $gadget->gadgetSpec->userPrefs[$key]['enumValues'][$enumKey]['value'] = $gadget->substitutions->substitute($enumVal['value']);
 102           $gadget->gadgetSpec->userPrefs[$key]['enumValues'][$enumKey]['displayValue'] = $gadget->substitutions->substitute($enumVal['displayValue']);
 103         }
 104       }
 105     }
 106     // Apply substitutions to the preloads
 107     foreach ($gadget->gadgetSpec->preloads as $url => $preload) {
 108       $gadget->gadgetSpec->preloads[$url]['body'] = $gadget->substitutions->substitute($preload['body']);
 109     }
 110   }
 111
 112   /**
 113    * Seeds the substitutions class with the user prefs, messages, bidi and module id
 114    */
 115   private function addSubstitutions(Gadget &$gadget) {
 116     $gadget->substitutions = new Substitutions();
 117     if ($this->token) {
 118       $gadget->substitutions->addSubstitution('MODULE', "ID", $this->token->getModuleId());
 119     }
 120     if ($gadget->gadgetSpec->locales) {
 121       $gadget->substitutions->addSubstitutions('MSG', $gadget->gadgetSpec->locales);
 122     }
 123     $gadget->substitutions->addSubstitution('BIDI', "START_EDGE", $gadget->rightToLeft ? "right" : "left");
 124     $gadget->substitutions->addSubstitution('BIDI', "END_EDGE", $gadget->rightToLeft ? "left" : "right");
 125     $gadget->substitutions->addSubstitution('BIDI', "DIR", $gadget->rightToLeft ? "rtl" : "ltr");
 126     $gadget->substitutions->addSubstitution('BIDI', "REVERSE_DIR", $gadget->rightToLeft ? "ltr" : "rtl");
 127     foreach ($gadget->gadgetSpec->userPrefs as $pref) {
 128       $gadget->substitutions->addSubstitution('UP', $gadget->substitutions->substitute($pref['name']), $gadget->substitutions->substitute($pref['value']));
 129     }
 130   }
 131   /**
 132    * Process the UserPrefs values based on the current context
 133    *
 134    * @param Gadget $gadget
 135    */
 136   private function parseUserPrefs(Gadget &$gadget) {
 137     foreach ($gadget->gadgetSpec->userPrefs as $key => $pref) {
 138       $queryKey = 'up_'.$pref['name'];
 139       $gadget->gadgetSpec->userPrefs[$key]['value'] = isset($_GET[$queryKey]) ? trim(urldecode($_GET[$queryKey])) : $pref['defaultValue'];
 140     }
 141   }
 142
 143   /**
 144    * Merges all matching Message bundles, with a full match (lang and country) having the
 145    * highest priority and all/all having the lowest.
 146    *
 147    * This distills the locales array's back to one array of translations, which is then exposed
 148    * through the $gadget->substitutions class
 149    *
 150    * @param Gadget $gadget
 151    */
 152   private function mergeLocales(Gadget $gadget) {
 153     if (count($gadget->gadgetSpec->locales)) {
 154       $contextLocale = $this->context->getLocale();
 155       $locales = $gadget->gadgetSpec->locales;
 156       $gadget->rightToLeft  = false;
 157       $full = $partial = $all = null;
 158       foreach ($locales as $locale) {
 159         if ($locale['lang'] == $contextLocale['lang'] && $locale['country'] == $contextLocale['country']) {
 160           $full = $locale['messageBundle'];
 161           $gadget->rightToLeft = $locale['languageDirection'] == 'rtl';
 162         } elseif ($locale['lang'] == $contextLocale['lang'] && $locale['country'] == 'all') {
 163           $partial = $locale['messageBundle'];
 164         } elseif ($locale['country'] == 'all' && $locale['lang'] == 'all') {
 165           $all = $locale['messageBundle'];
 166         }
 167       }
 168       $gadget->gadgetSpec->locales = array();
 169       // array_merge overwrites duplicate keys from param 2 over param 1, so $full takes precedence over partial, and it over all
 170       if ($full) $gadget->gadgetSpec->locales = array_merge($full, $gadget->gadgetSpec->locales);
 171       if ($partial) $gadget->gadgetSpec->locales = array_merge($partial, $gadget->gadgetSpec->locales);
 172       if ($all) $gadget->gadgetSpec->locales = array_merge($all, $gadget->gadgetSpec->locales);
 173     }
 174   }
 175
 176   /**
 177    * Fetches all remote resources simultaniously using a multiFetchRequest to optimize rendering time.
 178    *
 179    * The preloads will be json_encoded to their gadget document injection format, and the locales will
 180    * be reduced to only the GadgetContext->getLocale matching entries.
 181    *
 182    * @param Gadget $gadget
 183    * @param GadgetContext $context
 184    */
 185   private function fetchResources(Gadget &$gadget) {
 186     $contextLocale = $this->context->getLocale();
 187     $unsignedRequests = $unsignedContexts = $signedRequests = array();
 188     foreach ($gadget->getLocales() as $key => $locale) {
 189       // Only fetch the locales that match the current context's language and country
 190       if (($locale['country'] == 'all' && $locale['lang'] == 'all') || ($locale['lang'] == $contextLocale['lang'] && $locale['country'] == 'all') || ($locale['lang'] == $contextLocale['lang'] && $locale['country'] == $contextLocale['country'])) {
 191         if (!empty($locale['messages'])) {
 192           // locale matches the current context, add it to the requests queue
 193           $unsignedRequests[] = $locale['messages'];
 194         }
 195       } else {
 196         // remove any locales that are not applicable to this context
 197         unset($gadget->gadgetSpec->locales[$key]);
 198       }
 199     }
 200     // Add preloads to the request queue
 201     foreach ($gadget->getPreloads() as $preload) {
 202       if (!empty($preload['href'])) {
 203         if (!empty($preload['authz']) && $preload['authz'] == 'SIGNED') {
 204           if ($this->token == '') {
 205             throw new GadgetException("Signed preloading requested, but no valid security token set");
 206           }
 207           $signedRequests[] = $preload['href'];
 208         } else {
 209           $unsignedRequests[] = $preload['href'];
 210         }
 211       }
 212     }
 213     // Perform the non-signed requests
 214     foreach ($unsignedRequests as $key => $requestUrl) {
 215       $request = new RemoteContentRequest($requestUrl);
 216       $request->createRemoteContentRequestWithUri($requestUrl);
 217       $unsignedRequests[$key] = $request;
 218       $unsignedContexts[$key] = $this->context;
 219     }
 220     $responses = array();
 221     if (count($unsignedRequests)) {
 222       $brc = new BasicRemoteContent();
 223       $resps = $brc->multiFetch($unsignedRequests, $unsignedContexts);
 224       foreach ($resps as $response) {
 225         $responses[$response->getUrl()] = array(
 226             'body' => $response->getResponseContent(),
 227             'rc' => $response->getHttpCode());
 228       }
 229     }
 230     // Perform the signed requests
 231     foreach ($signedRequests as $key => $requestUrl) {
 232       $request = new RemoteContentRequest($requestUrl);
 233       $request->createRemoteContentRequestWithUri($requestUrl);
 234       $signedRequests[$key] = $request;
 235       $signingFetcherFactory = new SigningFetcherFactory(Config::get("private_key_file"));
 236       $fetcher = $signingFetcherFactory->getSigningFetcher(new BasicRemoteContentFetcher(), $this->token);
 237       $req = $fetcher->signRequest($requestUrl, 'GET');
 238       $req->setNotSignedUri($requestUrl);
 239       $signedRequests[] = $req;
 240     }
 241     if (count($signedRequests)) {
 242       $fetcher = $signingFetcherFactory->getSigningFetcher(new BasicRemoteContentFetcher(), $this->token);
 243       $resps = $fetcher->multiFetchRequest($signedRequests);
 244       foreach ($resps as $response) {
 245         $responses[$response->getNotSignedUrl()] = array(
 246             'body' => $response->getResponseContent(),
 247             'rc' => $response->getHttpCode());
 248       }
 249     }
 250     // assign the results to the gadget locales and preloads (using the url as the key)
 251     foreach ($gadget->gadgetSpec->locales as $key => $locale) {
 252       if (!empty($locale['messages']) && isset($responses[$locale['messages']]) && $responses[$locale['messages']]['rc'] == 200) {
 253         $gadget->gadgetSpec->locales[$key]['messageBundle'] = $this->parseMessageBundle($responses[$locale['messages']]['body']);
 254       }
 255     }
 256     $preloads = array();
 257     foreach ($gadget->gadgetSpec->preloads as $key => $preload) {
 258       if (!empty($preload['href']) && isset($responses[$preload['href']]) && $responses[$preload['href']]['rc'] == 200) {
 259         $preloads[$preload['href']] = $responses[$preload['href']];
 260       }
 261     }
 262     $gadget->gadgetSpec->preloads = $preloads;
 263   }
 264
 265   /**
 266    * Parses the (remote / fetched) message bundle xml
 267    *
 268    * @param string $messageBundleData
 269    * @return array (MessageBundle)
 270    */
 271   private function parseMessageBundle($messageBundleData) {
 272     libxml_use_internal_errors(true);
 273     $doc = new DOMDocument();
 274     if (! $doc->loadXML($messageBundleData, LIBXML_NOCDATA)) {
 275       $errors = libxml_get_errors();
 276       $errorStr = '';
 277       foreach ($errors as $error) {
 278         $errorStr .= $error . " \n";
 279       }
 280       libxml_clear_errors();
 281       throw new GadgetSpecException("Error parsing gadget xml:\n$errorStr");
 282     }
 283     $messageBundle = array();
 284     if (($messageBundleNode = $doc->getElementsByTagName('messagebundle')) != null && $messageBundleNode->length > 0) {
 285       $messageBundleNode = $messageBundleNode->item(0);
 286       $messages = $messageBundleNode->getElementsByTagName('msg');
 287       foreach ($messages as $msg) {
 288         $messageBundle[$msg->getAttribute('name')] = trim($msg->nodeValue);
 289       }
 290     }
 291     return $messageBundle;
 292   }
 293
 294   /**
 295    * Fetches the gadget xml for the requested URL using the http fetcher
 296    *
 297    * @param unknown_type $gadgetUrl
 298    * @return string gadget's xml content
 299    */
 300   protected function fetchGadget($gadgetUrl) {
 301     $request = new RemoteContentRequest($gadgetUrl);
 302     $xml = $this->context->getHttpFetcher()->fetch($request, $this->context);
 303     if ($xml->getHttpCode() != '200') {
 304       throw new GadgetException("Failed to retrieve gadget content (recieved http code " . $xml->getHttpCode() . ")");
 305     }
 306     return $xml->getResponseContent();
 307   }
 308 }