CRM/Core/BAO/Cache.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  * BAO object for civicrm_cache table.
  30  *
  31  * This is a database cache and is persisted across sessions. Typically we use
  32  * this to store meta data (like profile fields, custom fields etc).
  33  *
  34  * The group_name column is used for grouping together all cache elements that logically belong to the same set.
  35  * Thus all session cache entries are grouped under 'CiviCRM Session'. This allows us to delete all entries of
  36  * a specific group if needed.
  37  *
  38  * The path column allows us to differentiate between items in that group. Thus for the session cache, the path is
  39  * the unique form name for each form (per user)
  40  */
  41 class CRM_Core_BAO_Cache extends CRM_Core_DAO_Cache {
  42
  43   /**
  44    * When store session/form state, how long should the data be retained?
  45    *
  46    * Default is Two days: 2*24*60*60
  47    *
  48    * @var int, number of second
  49    */
  50   const DEFAULT_SESSION_TTL = 172800;
  51
  52   /**
  53    * Cache.
  54    *
  55    * Format is ($cacheKey => $cacheValue)
  56    *
  57    * @var array
  58    */
  59   public static $_cache = NULL;
  60
  61   /**
  62    * Retrieve an item from the DB cache.
  63    *
  64    * @param string $group
  65    *   (required) The group name of the item.
  66    * @param string $path
  67    *   (required) The path under which this item is stored.
  68    * @param int $componentID
  69    *   The optional component ID (so componenets can share the same name space).
  70    *
  71    * @return object
  72    *   The data if present in cache, else null
  73    * @deprecated
  74    */
  75   public static function &getItem($group, $path, $componentID = NULL) {
  76     if (($adapter = CRM_Utils_Constant::value('CIVICRM_BAO_CACHE_ADAPTER')) !== NULL) {
  77       $value = $adapter::getItem($group, $path, $componentID);
  78       return $value;
  79     }
  80
  81     if (self::$_cache === NULL) {
  82       self::$_cache = [];
  83     }
  84
  85     $argString = "CRM_CT_{$group}_{$path}_{$componentID}";
  86     if (!array_key_exists($argString, self::$_cache)) {
  87       $cache = CRM_Utils_Cache::singleton();
  88       $cleanKey = self::cleanKey($argString);
  89       self::$_cache[$argString] = $cache->get($cleanKey);
  90       if (self::$_cache[$argString] === NULL) {
  91         $table = self::getTableName();
  92         $where = self::whereCache($group, $path, $componentID);
  93         $rawData = CRM_Core_DAO::singleValueQuery("SELECT data FROM $table WHERE $where");
  94         $data = $rawData ? self::decode($rawData) : NULL;
  95
  96         self::$_cache[$argString] = $data;
  97         if ($data !== NULL) {
  98           // Do not cache 'null' as that is most likely a cache miss & we shouldn't then cache it.
  99           $cache->set($cleanKey, self::$_cache[$argString]);
 100         }
 101       }
 102     }
 103     return self::$_cache[$argString];
 104   }
 105
 106   /**
 107    * Retrieve all items in a group.
 108    *
 109    * @param string $group
 110    *   (required) The group name of the item.
 111    * @param int $componentID
 112    *   The optional component ID (so componenets can share the same name space).
 113    *
 114    * @return object
 115    *   The data if present in cache, else null
 116    * @deprecated
 117    */
 118   public static function &getItems($group, $componentID = NULL) {
 119     if (($adapter = CRM_Utils_Constant::value('CIVICRM_BAO_CACHE_ADAPTER')) !== NULL) {
 120       return $adapter::getItems($group, $componentID);
 121     }
 122
 123     if (self::$_cache === NULL) {
 124       self::$_cache = [];
 125     }
 126
 127     $argString = "CRM_CT_CI_{$group}_{$componentID}";
 128     if (!array_key_exists($argString, self::$_cache)) {
 129       $cache = CRM_Utils_Cache::singleton();
 130       $cleanKey = self::cleanKey($argString);
 131       self::$_cache[$argString] = $cache->get($cleanKey);
 132       if (!self::$_cache[$argString]) {
 133         $table = self::getTableName();
 134         $where = self::whereCache($group, NULL, $componentID);
 135         $dao = CRM_Core_DAO::executeQuery("SELECT path, data FROM $table WHERE $where");
 136
 137         $result = [];
 138         while ($dao->fetch()) {
 139           $result[$dao->path] = self::decode($dao->data);
 140         }
 141
 142         self::$_cache[$argString] = $result;
 143         $cache->set($cleanKey, self::$_cache[$argString]);
 144       }
 145     }
 146
 147     return self::$_cache[$argString];
 148   }
 149
 150   /**
 151    * Store an item in the DB cache.
 152    *
 153    * @param object $data
 154    *   (required) A reference to the data that will be serialized and stored.
 155    * @param string $group
 156    *   (required) The group name of the item.
 157    * @param string $path
 158    *   (required) The path under which this item is stored.
 159    * @param int $componentID
 160    *   The optional component ID (so componenets can share the same name space).
 161    * @deprecated
 162    */
 163   public static function setItem(&$data, $group, $path, $componentID = NULL) {
 164     if (($adapter = CRM_Utils_Constant::value('CIVICRM_BAO_CACHE_ADAPTER')) !== NULL) {
 165       return $adapter::setItem($data, $group, $path, $componentID);
 166     }
 167
 168     if (self::$_cache === NULL) {
 169       self::$_cache = [];
 170     }
 171
 172     // get a lock so that multiple ajax requests on the same page
 173     // dont trample on each other
 174     // CRM-11234
 175     $lock = Civi::lockManager()->acquire("cache.{$group}_{$path}._{$componentID}");
 176     if (!$lock->isAcquired()) {
 177       CRM_Core_Error::fatal();
 178     }
 179
 180     $table = self::getTableName();
 181     $where = self::whereCache($group, $path, $componentID);
 182     $dataExists = CRM_Core_DAO::singleValueQuery("SELECT COUNT(*) FROM $table WHERE {$where}");
 183     // FIXME - Use SQL NOW() or CRM_Utils_Time?
 184     $now = date('Y-m-d H:i:s');
 185     $dataSerialized = self::encode($data);
 186
 187     // This table has a wonky index, so we cannot use REPLACE or
 188     // "INSERT ... ON DUPE". Instead, use SELECT+(INSERT|UPDATE).
 189     if ($dataExists) {
 190       $sql = "UPDATE $table SET data = %1, created_date = %2 WHERE {$where}";
 191       $args = [
 192         1 => [$dataSerialized, 'String'],
 193         2 => [$now, 'String'],
 194       ];
 195       $dao = CRM_Core_DAO::executeQuery($sql, $args, TRUE, NULL, FALSE, FALSE);
 196     }
 197     else {
 198       $insert = CRM_Utils_SQL_Insert::into($table)
 199         ->row([
 200           'group_name' => $group,
 201           'path' => $path,
 202           'component_id' => $componentID,
 203           'data' => $dataSerialized,
 204           'created_date' => $now,
 205         ]);
 206       $dao = CRM_Core_DAO::executeQuery($insert->toSQL(), [], TRUE, NULL, FALSE, FALSE);
 207     }
 208
 209     $lock->release();
 210
 211     // cache coherency - refresh or remove dependent caches
 212
 213     $argString = "CRM_CT_{$group}_{$path}_{$componentID}";
 214     $cache = CRM_Utils_Cache::singleton();
 215     $data = self::decode($dataSerialized);
 216     self::$_cache[$argString] = $data;
 217     $cache->set(self::cleanKey($argString), $data);
 218
 219     $argString = "CRM_CT_CI_{$group}_{$componentID}";
 220     unset(self::$_cache[$argString]);
 221     $cache->delete(self::cleanKey($argString));
 222   }
 223
 224   /**
 225    * Delete all the cache elements that belong to a group OR delete the entire cache if group is not specified.
 226    *
 227    * @param string $group
 228    *   The group name of the entries to be deleted.
 229    * @param string $path
 230    *   Path of the item that needs to be deleted.
 231    * @param bool $clearAll clear all caches
 232    * @deprecated
 233    */
 234   public static function deleteGroup($group = NULL, $path = NULL, $clearAll = TRUE) {
 235     if (($adapter = CRM_Utils_Constant::value('CIVICRM_BAO_CACHE_ADAPTER')) !== NULL) {
 236       return $adapter::deleteGroup($group, $path);
 237     }
 238     else {
 239       $table = self::getTableName();
 240       $where = self::whereCache($group, $path, NULL);
 241       CRM_Core_DAO::executeQuery("DELETE FROM $table WHERE $where");
 242     }
 243
 244     if ($clearAll) {
 245       // also reset ACL Cache
 246       CRM_ACL_BAO_Cache::resetCache();
 247
 248       // also reset memory cache if any
 249       CRM_Utils_System::flushCache();
 250     }
 251   }
 252
 253   /**
 254    * The next two functions are internal functions used to store and retrieve session from
 255    * the database cache. This keeps the session to a limited size and allows us to
 256    * create separate session scopes for each form in a tab
 257    */
 258
 259   /**
 260    * This function takes entries from the session array and stores it in the cache.
 261    *
 262    * It also deletes the entries from the $_SESSION object (for a smaller session size)
 263    *
 264    * @param array $names
 265    *   Array of session values that should be persisted.
 266    *                     This is either a form name + qfKey or just a form name
 267    *                     (in the case of profile)
 268    * @param bool $resetSession
 269    *   Should session state be reset on completion of DB store?.
 270    */
 271   public static function storeSessionToCache($names, $resetSession = TRUE) {
 272     foreach ($names as $key => $sessionName) {
 273       if (is_array($sessionName)) {
 274         $value = NULL;
 275         if (!empty($_SESSION[$sessionName[0]][$sessionName[1]])) {
 276           $value = $_SESSION[$sessionName[0]][$sessionName[1]];
 277         }
 278         $key = "{$sessionName[0]}_{$sessionName[1]}";
 279         Civi::cache('session')->set($key, $value, self::pickSessionTtl($key));
 280         if ($resetSession) {
 281           $_SESSION[$sessionName[0]][$sessionName[1]] = NULL;
 282           unset($_SESSION[$sessionName[0]][$sessionName[1]]);
 283         }
 284       }
 285       else {
 286         $value = NULL;
 287         if (!empty($_SESSION[$sessionName])) {
 288           $value = $_SESSION[$sessionName];
 289         }
 290         Civi::cache('session')->set($sessionName, $value, self::pickSessionTtl($sessionName));
 291         if ($resetSession) {
 292           $_SESSION[$sessionName] = NULL;
 293           unset($_SESSION[$sessionName]);
 294         }
 295       }
 296     }
 297
 298     self::cleanup();
 299   }
 300
 301   /* Retrieve the session values from the cache and populate the $_SESSION array
 302    *
 303    * @param array $names
 304    *   Array of session values that should be persisted.
 305    *                     This is either a form name + qfKey or just a form name
 306    *                     (in the case of profile)
 307    */
 308
 309   /**
 310    * Restore session from cache.
 311    *
 312    * @param string $names
 313    */
 314   public static function restoreSessionFromCache($names) {
 315     foreach ($names as $key => $sessionName) {
 316       if (is_array($sessionName)) {
 317         $value = Civi::cache('session')->get("{$sessionName[0]}_{$sessionName[1]}");
 318         if ($value) {
 319           $_SESSION[$sessionName[0]][$sessionName[1]] = $value;
 320         }
 321       }
 322       else {
 323         $value = Civi::cache('session')->get($sessionName);
 324         if ($value) {
 325           $_SESSION[$sessionName] = $value;
 326         }
 327       }
 328     }
 329   }
 330
 331   /**
 332    * Determine how long session-state should be retained.
 333    *
 334    * @param string $sessionKey
 335    *   Ex: '_CRM_Admin_Form_Preferences_Display_f1a5f232e3d850a29a7a4d4079d7c37b_4654_container'
 336    *   Ex: 'CiviCRM_CRM_Admin_Form_Preferences_Display_f1a5f232e3d850a29a7a4d4079d7c37b_4654'
 337    * @return int
 338    *   Number of seconds.
 339    */
 340   protected static function pickSessionTtl($sessionKey) {
 341     $secureSessionTimeoutMinutes = (int) Civi::settings()->get('secure_cache_timeout_minutes');
 342     if ($secureSessionTimeoutMinutes) {
 343       $transactionPages = [
 344         'CRM_Contribute_Controller_Contribution',
 345         'CRM_Event_Controller_Registration',
 346       ];
 347       foreach ($transactionPages as $transactionPage) {
 348         if (strpos($sessionKey, $transactionPage) !== FALSE) {
 349           return $secureSessionTimeoutMinutes * 60;
 350         }
 351       }
 352     }
 353
 354     return self::DEFAULT_SESSION_TTL;
 355   }
 356
 357   /**
 358    * Do periodic cleanup of the CiviCRM session table.
 359    *
 360    * Also delete all session cache entries which are a couple of days old.
 361    * This keeps the session cache to a manageable size
 362    * Delete Contribution page session caches more energetically.
 363    *
 364    * @param bool $session
 365    * @param bool $table
 366    * @param bool $prevNext
 367    * @param bool $expired
 368    */
 369   public static function cleanup($session = FALSE, $table = FALSE, $prevNext = FALSE, $expired = FALSE) {
 370     // clean up the session cache every $cacheCleanUpNumber probabilistically
 371     $cleanUpNumber = 757;
 372
 373     // clean up all sessions older than $cacheTimeIntervalDays days
 374     $timeIntervalDays = 2;
 375
 376     if (mt_rand(1, 100000) % $cleanUpNumber == 0) {
 377       $expired = $session = $table = $prevNext = TRUE;
 378     }
 379
 380     if (!$session && !$table && !$prevNext && !$expired) {
 381       return;
 382     }
 383
 384     if ($prevNext) {
 385       // delete all PrevNext caches
 386       CRM_Core_BAO_PrevNextCache::cleanupCache();
 387     }
 388
 389     if ($table) {
 390       CRM_Core_Config::clearTempTables($timeIntervalDays . ' day');
 391     }
 392
 393     if ($session) {
 394       // Session caches are just regular caches, so they expire naturally per TTL.
 395       $expired = TRUE;
 396     }
 397
 398     if ($expired) {
 399       $sql = "DELETE FROM civicrm_cache WHERE expired_date < %1";
 400       $params = [
 401         1 => [date(CRM_Utils_Cache_SqlGroup::TS_FMT, CRM_Utils_Time::getTimeRaw()), 'String'],
 402       ];
 403       CRM_Core_DAO::executeQuery($sql, $params);
 404     }
 405   }
 406
 407   /**
 408    * (Quasi-private) Encode an object/array/string/int as a string.
 409    *
 410    * @param $mixed
 411    * @return string
 412    */
 413   public static function encode($mixed) {
 414     return base64_encode(serialize($mixed));
 415   }
 416
 417   /**
 418    * (Quasi-private) Decode an object/array/string/int from a string.
 419    *
 420    * @param $string
 421    * @return mixed
 422    */
 423   public static function decode($string) {
 424     // Upgrade support -- old records (serialize) always have this punctuation,
 425     // and new records (base64) never do.
 426     if (strpos($string, ':') !== FALSE || strpos($string, ';') !== FALSE) {
 427       return unserialize($string);
 428     }
 429     else {
 430       return unserialize(base64_decode($string));
 431     }
 432   }
 433
 434   /**
 435    * Compose a SQL WHERE clause for the cache.
 436    *
 437    * Note: We need to use the cache during bootstrap, so we don't have
 438    * full access to DAO services.
 439    *
 440    * @param string $group
 441    * @param string|null $path
 442    *   Filter by path. If NULL, then return any paths.
 443    * @param int|null $componentID
 444    *   Filter by component. If NULL, then look for explicitly NULL records.
 445    * @return string
 446    */
 447   protected static function whereCache($group, $path, $componentID) {
 448     $clauses = [];
 449     $clauses[] = ('group_name = "' . CRM_Core_DAO::escapeString($group) . '"');
 450     if ($path) {
 451       $clauses[] = ('path = "' . CRM_Core_DAO::escapeString($path) . '"');
 452     }
 453     if ($componentID && is_numeric($componentID)) {
 454       $clauses[] = ('component_id = ' . (int) $componentID);
 455     }
 456     return $clauses ? implode(' AND ', $clauses) : '(1)';
 457   }
 458
 459   /**
 460    * Normalize a cache key.
 461    *
 462    * This bridges an impedance mismatch between our traditional caching
 463    * and PSR-16 -- PSR-16 accepts a narrower range of cache keys.
 464    *
 465    * @param string $key
 466    *   Ex: 'ab/cd:ef'
 467    * @return string
 468    *   Ex: '_abcd1234abcd1234' or 'ab_xx/cd_xxef'.
 469    *   A similar key, but suitable for use with PSR-16-compliant cache providers.
 470    */
 471   public static function cleanKey($key) {
 472     if (!is_string($key) && !is_int($key)) {
 473       throw new \RuntimeException("Malformed cache key");
 474     }
 475
 476     $maxLen = 64;
 477     $escape = '-';
 478
 479     if (strlen($key) >= $maxLen) {
 480       return $escape . md5($key);
 481     }
 482
 483     $r = preg_replace_callback(';[^A-Za-z0-9_\.];', function($m) use ($escape) {
 484       return $escape . dechex(ord($m[0]));
 485     }, $key);
 486
 487     return strlen($r) >= $maxLen ? $escape . md5($key) : $r;
 488   }
 489
 490 }