CRM/Core/CommunityMessages.php

   1 <?php
   2 /*
   3  +--------------------------------------------------------------------+
   4  | Copyright CiviCRM LLC. All rights reserved.                        |
   5  |                                                                    |
   6  | This work is published under the GNU AGPLv3 license with some      |
   7  | permitted exceptions and without any warranty. For full license    |
   8  | and copyright information, see https://civicrm.org/licensing       |
   9  +--------------------------------------------------------------------+
  10  */
  11
  12 /**
  13  * Manage the download, validation, and rendering of community messages
  14  */
  15 class CRM_Core_CommunityMessages {
  16
  17   const DEFAULT_MESSAGES_URL = 'https://alert.civicrm.org/alert?prot=1&ver={ver}&uf={uf}&sid={sid}&lang={lang}&co={co}';
  18   const DEFAULT_PERMISSION = 'administer CiviCRM';
  19
  20   /**
  21    * Default time to wait before retrying.
  22    */
  23   // 2 hours
  24   const DEFAULT_RETRY = 7200;
  25
  26   /**
  27    * @var CRM_Utils_HttpClient
  28    */
  29   protected $client;
  30
  31   /**
  32    * @var CRM_Utils_Cache_Interface
  33    */
  34   protected $cache;
  35
  36   /**
  37    * Url to retrieve community messages from.
  38    *
  39    * False means a retrieval will not be attempted.
  40    *
  41    * @var false|string
  42    */
  43   protected $messagesUrl;
  44
  45   /**
  46    * Create default instance.
  47    *
  48    * @return CRM_Core_CommunityMessages
  49    */
  50   public static function create() {
  51     return new CRM_Core_CommunityMessages(
  52       Civi::cache('community_messages'),
  53       CRM_Utils_HttpClient::singleton()
  54     );
  55   }
  56
  57   /**
  58    * Class constructor.
  59    *
  60    * @param CRM_Utils_Cache_Interface $cache
  61    * @param CRM_Utils_HttpClient $client
  62    * @param string|false $messagesUrl
  63    */
  64   public function __construct($cache, $client, $messagesUrl = NULL) {
  65     $this->cache = $cache;
  66     $this->client = $client;
  67     if ($messagesUrl === NULL) {
  68       $this->messagesUrl = Civi::settings()->get('communityMessagesUrl');
  69     }
  70     else {
  71       $this->messagesUrl = $messagesUrl;
  72     }
  73     if ($this->messagesUrl === '*default*') {
  74       $this->messagesUrl = self::DEFAULT_MESSAGES_URL;
  75     }
  76   }
  77
  78   /**
  79    * Get the messages document (either from the cache or by downloading).
  80    *
  81    * @return NULL|array
  82    */
  83   public function getDocument() {
  84     $isChanged = FALSE;
  85     $document = $this->cache->get('communityMessages');
  86
  87     if (empty($document) || !is_array($document)) {
  88       $document = [
  89         'messages' => [],
  90         // ASAP
  91         'expires' => 0,
  92         'ttl' => self::DEFAULT_RETRY,
  93         'retry' => self::DEFAULT_RETRY,
  94       ];
  95       $isChanged = TRUE;
  96     }
  97
  98     $refTime = CRM_Utils_Time::getTimeRaw();
  99     if ($document['expires'] <= $refTime) {
 100       $newDocument = $this->fetchDocument();
 101       if ($newDocument && $this->validateDocument($newDocument)) {
 102         $document = $newDocument;
 103         $document['expires'] = $refTime + $document['ttl'];
 104       }
 105       else {
 106         // keep the old messages for now, try again later
 107         $document['expires'] = $refTime + $document['retry'];
 108       }
 109       $isChanged = TRUE;
 110     }
 111
 112     if ($isChanged) {
 113       $this->cache->set('communityMessages', $document);
 114     }
 115
 116     return $document;
 117   }
 118
 119   /**
 120    * Download document from URL and parse as JSON.
 121    *
 122    * @return NULL|array
 123    *   parsed JSON
 124    */
 125   public function fetchDocument() {
 126     list($status, $json) = $this->client->get($this->getRenderedUrl());
 127     if ($status != CRM_Utils_HttpClient::STATUS_OK || empty($json)) {
 128       return NULL;
 129     }
 130     $doc = json_decode($json, TRUE);
 131     if (empty($doc) || json_last_error() != JSON_ERROR_NONE) {
 132       return NULL;
 133     }
 134     return $doc;
 135   }
 136
 137   /**
 138    * Get the final, usable URL string (after interpolating any variables)
 139    *
 140    * @return FALSE|string
 141    */
 142   public function getRenderedUrl() {
 143     return CRM_Utils_System::evalUrl($this->messagesUrl);
 144   }
 145
 146   /**
 147    * @return bool
 148    */
 149   public function isEnabled() {
 150     return $this->messagesUrl !== FALSE && $this->messagesUrl !== 'FALSE';
 151   }
 152
 153   /**
 154    * Pick a message to display.
 155    *
 156    * @return NULL|array
 157    */
 158   public function pick() {
 159     $document = $this->getDocument();
 160     $messages = [];
 161     foreach ($document['messages'] as $message) {
 162       if (!isset($message['perms'])) {
 163         $message['perms'] = [self::DEFAULT_PERMISSION];
 164       }
 165       if (!CRM_Core_Permission::checkAnyPerm($message['perms'])) {
 166         continue;
 167       }
 168
 169       if (isset($message['components'])) {
 170         $enabled = array_keys(CRM_Core_Component::getEnabledComponents());
 171         if (count(array_intersect($enabled, $message['components'])) == 0) {
 172           continue;
 173         }
 174       }
 175
 176       $messages[] = $message;
 177     }
 178     if (empty($messages)) {
 179       return NULL;
 180     }
 181
 182     $idx = rand(0, count($messages) - 1);
 183     return $messages[$idx];
 184   }
 185
 186   /**
 187    * @param string $markup
 188    * @return string
 189    */
 190   public static function evalMarkup($markup) {
 191     $config = CRM_Core_Config::singleton();
 192     $vals = [
 193       'resourceUrl' => rtrim($config->resourceBase, '/'),
 194       'ver' => CRM_Utils_System::version(),
 195       'uf' => $config->userFramework,
 196       'php' => phpversion(),
 197       'sid' => CRM_Utils_System::getSiteID(),
 198       'baseUrl' => $config->userFrameworkBaseURL,
 199       'lang' => $config->lcMessages,
 200       'co' => $config->defaultContactCountry ?? '',
 201     ];
 202     $vars = [];
 203     foreach ($vals as $k => $v) {
 204       $vars['%%' . $k . '%%'] = $v;
 205       $vars['{{' . $k . '}}'] = urlencode($v);
 206     }
 207     return strtr($markup, $vars);
 208   }
 209
 210   /**
 211    * Ensure that a document is well-formed
 212    *
 213    * @param array $document
 214    * @return bool
 215    */
 216   public function validateDocument($document) {
 217     if (!isset($document['ttl']) || !is_int($document['ttl'])) {
 218       return FALSE;
 219     }
 220     if (!isset($document['retry']) || !is_int($document['retry'])) {
 221       return FALSE;
 222     }
 223     if (!isset($document['messages']) || !is_array($document['messages'])) {
 224       return FALSE;
 225     }
 226     foreach ($document['messages'] as $message) {
 227       // TODO validate $message['markup']
 228     }
 229
 230     return TRUE;
 231   }
 232
 233 }