CRM/Core/BAO/Cache.php

   1 <?php
   2 /*
   3  +--------------------------------------------------------------------+
   4  | CiviCRM version 4.6                                                |
   5  +--------------------------------------------------------------------+
   6  | Copyright CiviCRM LLC (c) 2004-2014                                |
   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  *
  30  * @package CRM
  31  * @copyright CiviCRM LLC (c) 2004-2014
  32  * $Id$
  33  *
  34  */
  35
  36 /**
  37  * BAO object for civicrm_cache table. This is a database cache and is persisted across sessions. Typically we use
  38  * this to store meta data (like profile fields, custom fields etc).
  39  *
  40  * The group_name column is used for grouping together all cache elements that logically belong to the same set.
  41  * Thus all session cache entries are grouped under 'CiviCRM Session'. This allows us to delete all entries of
  42  * a specific group if needed.
  43  *
  44  * The path column allows us to differentiate between items in that group. Thus for the session cache, the path is
  45  * the unique form name for each form (per user)
  46  */
  47 class CRM_Core_BAO_Cache extends CRM_Core_DAO_Cache {
  48
  49   /**
  50    * @var array ($cacheKey => $cacheValue)
  51    */
  52   static $_cache = NULL;
  53
  54   /**
  55    * Retrieve an item from the DB cache.
  56    *
  57    * @param string $group
  58    *   (required) The group name of the item.
  59    * @param string $path
  60    *   (required) The path under which this item is stored.
  61    * @param int $componentID
  62    *   The optional component ID (so componenets can share the same name space).
  63    *
  64    * @return object
  65    *   The data if present in cache, else null
  66    */
  67   public static function &getItem($group, $path, $componentID = NULL) {
  68     if (self::$_cache === NULL) {
  69       self::$_cache = array();
  70     }
  71
  72     $argString = "CRM_CT_{$group}_{$path}_{$componentID}";
  73     if (!array_key_exists($argString, self::$_cache)) {
  74       $cache = CRM_Utils_Cache::singleton();
  75       self::$_cache[$argString] = $cache->get($argString);
  76       if (!self::$_cache[$argString]) {
  77         $dao = new CRM_Core_DAO_Cache();
  78
  79         $dao->group_name = $group;
  80         $dao->path = $path;
  81         $dao->component_id = $componentID;
  82
  83         $data = NULL;
  84         if ($dao->find(TRUE)) {
  85           $data = unserialize($dao->data);
  86         }
  87         $dao->free();
  88         self::$_cache[$argString] = $data;
  89         $cache->set($argString, self::$_cache[$argString]);
  90       }
  91     }
  92     return self::$_cache[$argString];
  93   }
  94
  95   /**
  96    * Retrieve all items in a group.
  97    *
  98    * @param string $group
  99    *   (required) The group name of the item.
 100    * @param int $componentID
 101    *   The optional component ID (so componenets can share the same name space).
 102    *
 103    * @return object
 104    *   The data if present in cache, else null
 105    */
 106   public static function &getItems($group, $componentID = NULL) {
 107     if (self::$_cache === NULL) {
 108       self::$_cache = array();
 109     }
 110
 111     $argString = "CRM_CT_CI_{$group}_{$componentID}";
 112     if (!array_key_exists($argString, self::$_cache)) {
 113       $cache = CRM_Utils_Cache::singleton();
 114       self::$_cache[$argString] = $cache->get($argString);
 115       if (!self::$_cache[$argString]) {
 116         $dao = new CRM_Core_DAO_Cache();
 117
 118         $dao->group_name = $group;
 119         $dao->component_id = $componentID;
 120         $dao->find();
 121
 122         $result = array(); // array($path => $data)
 123         while ($dao->fetch()) {
 124           $result[$dao->path] = unserialize($dao->data);
 125         }
 126         $dao->free();
 127
 128         self::$_cache[$argString] = $result;
 129         $cache->set($argString, self::$_cache[$argString]);
 130       }
 131     }
 132
 133     return self::$_cache[$argString];
 134   }
 135
 136   /**
 137    * Store an item in the DB cache.
 138    *
 139    * @param object $data
 140    *   (required) A reference to the data that will be serialized and stored.
 141    * @param string $group
 142    *   (required) The group name of the item.
 143    * @param string $path
 144    *   (required) The path under which this item is stored.
 145    * @param int $componentID
 146    *   The optional component ID (so componenets can share the same name space).
 147    *
 148    * @return void
 149    */
 150   public static function setItem(&$data, $group, $path, $componentID = NULL) {
 151     if (self::$_cache === NULL) {
 152       self::$_cache = array();
 153     }
 154
 155     $dao = new CRM_Core_DAO_Cache();
 156
 157     $dao->group_name = $group;
 158     $dao->path = $path;
 159     $dao->component_id = $componentID;
 160
 161     // get a lock so that multiple ajax requests on the same page
 162     // dont trample on each other
 163     // CRM-11234
 164     $lockName = "civicrm.cache.{$group}_{$path}._{$componentID}";
 165     $lock = new CRM_Core_Lock($lockName);
 166     if (!$lock->isAcquired()) {
 167       CRM_Core_Error::fatal();
 168     }
 169
 170     $dao->find(TRUE);
 171     $dao->data = serialize($data);
 172     $dao->created_date = date('YmdHis');
 173     $dao->save();
 174
 175     $lock->release();
 176
 177     $dao->free();
 178
 179     // cache coherency - refresh or remove dependent caches
 180
 181     $argString = "CRM_CT_{$group}_{$path}_{$componentID}";
 182     $cache = CRM_Utils_Cache::singleton();
 183     $data = unserialize($dao->data);
 184     self::$_cache[$argString] = $data;
 185     $cache->set($argString, $data);
 186
 187     $argString = "CRM_CT_CI_{$group}_{$componentID}";
 188     unset(self::$_cache[$argString]);
 189     $cache->delete($argString);
 190   }
 191
 192   /**
 193    * Delete all the cache elements that belong to a group OR
 194    * delete the entire cache if group is not specified
 195    *
 196    * @param string $group
 197    *   The group name of the entries to be deleted.
 198    * @param string $path
 199    *   Path of the item that needs to be deleted.
 200    * @param bool|\booleab $clearAll clear all caches
 201    *
 202    * @return void
 203    */
 204   public static function deleteGroup($group = NULL, $path = NULL, $clearAll = TRUE) {
 205     $dao = new CRM_Core_DAO_Cache();
 206
 207     if (!empty($group)) {
 208       $dao->group_name = $group;
 209     }
 210
 211     if (!empty($path)) {
 212       $dao->path = $path;
 213     }
 214
 215     $dao->delete();
 216
 217     if ($clearAll) {
 218       // also reset ACL Cache
 219       CRM_ACL_BAO_Cache::resetCache();
 220
 221       // also reset memory cache if any
 222       CRM_Utils_System::flushCache();
 223     }
 224   }
 225
 226   /**
 227    * The next two functions are internal functions used to store and retrieve session from
 228    * the database cache. This keeps the session to a limited size and allows us to
 229    * create separate session scopes for each form in a tab
 230    */
 231
 232   /**
 233    * This function takes entries from the session array and stores it in the cache.
 234    * It also deletes the entries from the $_SESSION object (for a smaller session size)
 235    *
 236    * @param array $names
 237    *   Array of session values that should be persisted.
 238    *                     This is either a form name + qfKey or just a form name
 239    *                     (in the case of profile)
 240    * @param bool $resetSession
 241    *   Should session state be reset on completion of DB store?.
 242    *
 243    * @return void
 244    */
 245   public static function storeSessionToCache($names, $resetSession = TRUE) {
 246     foreach ($names as $key => $sessionName) {
 247       if (is_array($sessionName)) {
 248         $value = NULL;
 249         if (!empty($_SESSION[$sessionName[0]][$sessionName[1]])) {
 250           $value = $_SESSION[$sessionName[0]][$sessionName[1]];
 251         }
 252         self::setItem($value, 'CiviCRM Session', "{$sessionName[0]}_{$sessionName[1]}");
 253         if ($resetSession) {
 254           $_SESSION[$sessionName[0]][$sessionName[1]] = NULL;
 255           unset($_SESSION[$sessionName[0]][$sessionName[1]]);
 256         }
 257       }
 258       else {
 259         $value = NULL;
 260         if (!empty($_SESSION[$sessionName])) {
 261           $value = $_SESSION[$sessionName];
 262         }
 263         self::setItem($value, 'CiviCRM Session', $sessionName);
 264         if ($resetSession) {
 265           $_SESSION[$sessionName] = NULL;
 266           unset($_SESSION[$sessionName]);
 267         }
 268       }
 269     }
 270
 271     self::cleanup();
 272   }
 273
 274   /* Retrieve the session values from the cache and populate the $_SESSION array
 275    *
 276    * @param array $names
 277    *   Array of session values that should be persisted.
 278    *                     This is either a form name + qfKey or just a form name
 279    *                     (in the case of profile)
 280    *
 281    * @return void
 282    */
 283
 284   /**
 285    * @param string $names
 286    */
 287   public static function restoreSessionFromCache($names) {
 288     foreach ($names as $key => $sessionName) {
 289       if (is_array($sessionName)) {
 290         $value = self::getItem('CiviCRM Session',
 291           "{$sessionName[0]}_{$sessionName[1]}"
 292         );
 293         if ($value) {
 294           $_SESSION[$sessionName[0]][$sessionName[1]] = $value;
 295         }
 296       }
 297       else {
 298         $value = self::getItem('CiviCRM Session',
 299           $sessionName
 300         );
 301         if ($value) {
 302           $_SESSION[$sessionName] = $value;
 303         }
 304       }
 305     }
 306   }
 307
 308   /**
 309    * Do periodic cleanup of the CiviCRM session table. Also delete all session cache entries
 310    * which are a couple of days old. This keeps the session cache to a manageable size
 311    *
 312    * @param bool $session
 313    * @param bool $table
 314    * @param bool $prevNext
 315    *
 316    * @return void
 317    */
 318   public static function cleanup($session = FALSE, $table = FALSE, $prevNext = FALSE) {
 319     // clean up the session cache every $cacheCleanUpNumber probabilistically
 320     $cleanUpNumber = 757;
 321
 322     // clean up all sessions older than $cacheTimeIntervalDays days
 323     $timeIntervalDays = 2;
 324     $timeIntervalMins = 30;
 325
 326     if (mt_rand(1, 100000) % $cleanUpNumber == 0) {
 327       $session = $table = $prevNext = TRUE;
 328     }
 329
 330     if (!$session && !$table && !$prevNext) {
 331       return;
 332     }
 333
 334     if ($prevNext) {
 335       // delete all PrevNext caches
 336       CRM_Core_BAO_PrevNextCache::cleanupCache();
 337     }
 338
 339     if ($table) {
 340       // also delete all the action temp tables
 341       // that were created the same interval ago
 342       $dao = new CRM_Core_DAO();
 343       $query = "
 344 SELECT TABLE_NAME as tableName
 345 FROM   INFORMATION_SCHEMA.TABLES
 346 WHERE  TABLE_SCHEMA = %1
 347 AND    ( TABLE_NAME LIKE 'civicrm_task_action_temp_%'
 348  OR      TABLE_NAME LIKE 'civicrm_export_temp_%'
 349  OR      TABLE_NAME LIKE 'civicrm_import_job_%' )
 350 AND    CREATE_TIME < date_sub( NOW( ), INTERVAL $timeIntervalDays day )
 351 ";
 352
 353       $params = array(1 => array($dao->database(), 'String'));
 354       $tableDAO = CRM_Core_DAO::executeQuery($query, $params);
 355       $tables = array();
 356       while ($tableDAO->fetch()) {
 357         $tables[] = $tableDAO->tableName;
 358       }
 359       if (!empty($tables)) {
 360         $table = implode(',', $tables);
 361         // drop leftover temporary tables
 362         CRM_Core_DAO::executeQuery("DROP TABLE $table");
 363       }
 364     }
 365
 366     if ($session) {
 367       // first delete all sessions which are related to any potential transaction
 368       // page
 369       $transactionPages = array(
 370         'CRM_Contribute_Controller_Contribution',
 371         'CRM_Event_Controller_Registration',
 372       );
 373
 374       $params = array(
 375         1 => array(date('Y-m-d H:i:s', time() - $timeIntervalMins * 60), 'String'),
 376       );
 377       foreach ($transactionPages as $trPage) {
 378         $params[] = array("%${trPage}%", 'String');
 379         $where[] = 'path LIKE %' . count($params);
 380       }
 381
 382       $sql = "
 383 DELETE FROM civicrm_cache
 384 WHERE       group_name = 'CiviCRM Session'
 385 AND         created_date <= %1
 386 AND         (" . implode(' OR ', $where) . ")";
 387       CRM_Core_DAO::executeQuery($sql, $params);
 388
 389       $sql = "
 390 DELETE FROM civicrm_cache
 391 WHERE       group_name = 'CiviCRM Session'
 392 AND         created_date < date_sub( NOW( ), INTERVAL $timeIntervalDays DAY )
 393 ";
 394       CRM_Core_DAO::executeQuery($sql);
 395     }
 396   }
 397
 398 }