CRM/Core/CommunityMessages.php

   1 <?php
   2 /*
   3  +--------------------------------------------------------------------+
   4  | CiviCRM version 5                                                  |
   5  +--------------------------------------------------------------------+
   6  | Copyright CiviCRM LLC (c) 2004-2019                                |
   7  +--------------------------------------------------------------------+
   8  | This file is a part of CiviCRM.                                    |
   9  |                                                                    |
  10  | CiviCRM is free software; you can copy, modify, and distribute it  |
  11  | under the terms of the GNU Affero General Public License           |
  12  | Version 3, 19 November 2007 and the CiviCRM Licensing Exception.   |
  13  |                                                                    |
  14  | CiviCRM is distributed in the hope that it will be useful, but     |
  15  | WITHOUT ANY WARRANTY; without even the implied warranty of         |
  16  | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.               |
  17  | See the GNU Affero General Public License for more details.        |
  18  |                                                                    |
  19  | You should have received a copy of the GNU Affero General Public   |
  20  | License and the CiviCRM Licensing Exception along                  |
  21  | with this program; if not, contact CiviCRM LLC                     |
  22  | at info[AT]civicrm[DOT]org. If you have questions about the        |
  23  | GNU Affero General Public License or the licensing of CiviCRM,     |
  24  | see the CiviCRM license FAQ at http://civicrm.org/licensing        |
  25  +--------------------------------------------------------------------+
  26  */
  27
  28 /**
  29  * Manage the download, validation, and rendering of community messages
  30  */
  31 class CRM_Core_CommunityMessages {
  32
  33   const DEFAULT_MESSAGES_URL = 'https://alert.civicrm.org/alert?prot=1&ver={ver}&uf={uf}&sid={sid}&lang={lang}&co={co}';
  34   const DEFAULT_PERMISSION = 'administer CiviCRM';
  35
  36   /**
  37    * Default time to wait before retrying.
  38    */
  39   // 2 hours
  40   const DEFAULT_RETRY = 7200;
  41
  42   /**
  43    * @var CRM_Utils_HttpClient
  44    */
  45   protected $client;
  46
  47   /**
  48    * @var CRM_Utils_Cache_Interface
  49    */
  50   protected $cache;
  51
  52   /**
  53    * Url to retrieve community messages from.
  54    *
  55    * False means a retrieval will not be attempted.
  56    *
  57    * @var false|string
  58    */
  59   protected $messagesUrl;
  60
  61   /**
  62    * Create default instance.
  63    *
  64    * @return CRM_Core_CommunityMessages
  65    */
  66   public static function create() {
  67     return new CRM_Core_CommunityMessages(
  68       Civi::cache('community_messages'),
  69       CRM_Utils_HttpClient::singleton()
  70     );
  71   }
  72
  73   /**
  74    * Class constructor.
  75    *
  76    * @param CRM_Utils_Cache_Interface $cache
  77    * @param CRM_Utils_HttpClient $client
  78    * @param string|false $messagesUrl
  79    */
  80   public function __construct($cache, $client, $messagesUrl = NULL) {
  81     $this->cache = $cache;
  82     $this->client = $client;
  83     if ($messagesUrl === NULL) {
  84       $this->messagesUrl = Civi::settings()->get('communityMessagesUrl');
  85     }
  86     else {
  87       $this->messagesUrl = $messagesUrl;
  88     }
  89     if ($this->messagesUrl === '*default*') {
  90       $this->messagesUrl = self::DEFAULT_MESSAGES_URL;
  91     }
  92   }
  93
  94   /**
  95    * Get the messages document (either from the cache or by downloading).
  96    *
  97    * @return NULL|array
  98    */
  99   public function getDocument() {
 100     $isChanged = FALSE;
 101     $document = $this->cache->get('communityMessages');
 102
 103     if (empty($document) || !is_array($document)) {
 104       $document = [
 105         'messages' => [],
 106         // ASAP
 107         'expires' => 0,
 108         'ttl' => self::DEFAULT_RETRY,
 109         'retry' => self::DEFAULT_RETRY,
 110       ];
 111       $isChanged = TRUE;
 112     }
 113
 114     if ($document['expires'] <= CRM_Utils_Time::getTimeRaw()) {
 115       $newDocument = $this->fetchDocument();
 116       if ($newDocument && $this->validateDocument($newDocument)) {
 117         $document = $newDocument;
 118         $document['expires'] = CRM_Utils_Time::getTimeRaw() + $document['ttl'];
 119       }
 120       else {
 121         // keep the old messages for now, try again later
 122         $document['expires'] = CRM_Utils_Time::getTimeRaw() + $document['retry'];
 123       }
 124       $isChanged = TRUE;
 125     }
 126
 127     if ($isChanged) {
 128       $this->cache->set('communityMessages', $document);
 129     }
 130
 131     return $document;
 132   }
 133
 134   /**
 135    * Download document from URL and parse as JSON.
 136    *
 137    * @return NULL|array
 138    *   parsed JSON
 139    */
 140   public function fetchDocument() {
 141     list($status, $json) = $this->client->get($this->getRenderedUrl());
 142     if ($status != CRM_Utils_HttpClient::STATUS_OK || empty($json)) {
 143       return NULL;
 144     }
 145     $doc = json_decode($json, TRUE);
 146     if (empty($doc) || json_last_error() != JSON_ERROR_NONE) {
 147       return NULL;
 148     }
 149     return $doc;
 150   }
 151
 152   /**
 153    * Get the final, usable URL string (after interpolating any variables)
 154    *
 155    * @return FALSE|string
 156    */
 157   public function getRenderedUrl() {
 158     return CRM_Utils_System::evalUrl($this->messagesUrl);
 159   }
 160
 161   /**
 162    * @return bool
 163    */
 164   public function isEnabled() {
 165     return $this->messagesUrl !== FALSE && $this->messagesUrl !== 'FALSE';
 166   }
 167
 168   /**
 169    * Pick a message to display.
 170    *
 171    * @return NULL|array
 172    */
 173   public function pick() {
 174     $document = $this->getDocument();
 175     $messages = [];
 176     foreach ($document['messages'] as $message) {
 177       if (!isset($message['perms'])) {
 178         $message['perms'] = [self::DEFAULT_PERMISSION];
 179       }
 180       if (!CRM_Core_Permission::checkAnyPerm($message['perms'])) {
 181         continue;
 182       }
 183
 184       if (isset($message['components'])) {
 185         $enabled = array_keys(CRM_Core_Component::getEnabledComponents());
 186         if (count(array_intersect($enabled, $message['components'])) == 0) {
 187           continue;
 188         }
 189       }
 190
 191       $messages[] = $message;
 192     }
 193     if (empty($messages)) {
 194       return NULL;
 195     }
 196
 197     $idx = rand(0, count($messages) - 1);
 198     return $messages[$idx];
 199   }
 200
 201   /**
 202    * @param string $markup
 203    * @return string
 204    */
 205   public static function evalMarkup($markup) {
 206     $config = CRM_Core_Config::singleton();
 207     $vals = [
 208       'resourceUrl' => rtrim($config->resourceBase, '/'),
 209       'ver' => CRM_Utils_System::version(),
 210       'uf' => $config->userFramework,
 211       'php' => phpversion(),
 212       'sid' => CRM_Utils_System::getSiteID(),
 213       'baseUrl' => $config->userFrameworkBaseURL,
 214       'lang' => $config->lcMessages,
 215       'co' => $config->defaultContactCountry,
 216     ];
 217     $vars = [];
 218     foreach ($vals as $k => $v) {
 219       $vars['%%' . $k . '%%'] = $v;
 220       $vars['{{' . $k . '}}'] = urlencode($v);
 221     }
 222     return strtr($markup, $vars);
 223   }
 224
 225   /**
 226    * Ensure that a document is well-formed
 227    *
 228    * @param array $document
 229    * @return bool
 230    */
 231   public function validateDocument($document) {
 232     if (!isset($document['ttl']) || !is_int($document['ttl'])) {
 233       return FALSE;
 234     }
 235     if (!isset($document['retry']) || !is_int($document['retry'])) {
 236       return FALSE;
 237     }
 238     if (!isset($document['messages']) || !is_array($document['messages'])) {
 239       return FALSE;
 240     }
 241     foreach ($document['messages'] as $message) {
 242       // TODO validate $message['markup']
 243     }
 244
 245     return TRUE;
 246   }
 247
 248 }