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