crm.fsf.org/20131203/files/sites/all/modules-old/ctools/includes/object-cache.inc

   1 <?php
   2
   3 /**
   4  * @file
   5  * The non-volatile object cache is used to store an object while it is
   6  * being edited, so that we don't have to save until we're completely
   7  * done. The cache should be 'cleaned' on a regular basis, meaning to
   8  * remove old objects from the cache, but otherwise the data in this
   9  * cache must remain stable, as it includes unsaved changes.
  10  */
  11
  12 /**
  13  * Get an object from the non-volatile ctools cache.
  14  *
  15  * This function caches in memory as well, so that multiple calls to this
  16  * will not result in multiple database reads.
  17  *
  18  * @param $obj
  19  *   A 128 character or less string to define what kind of object is being
  20  *   stored; primarily this is used to prevent collisions.
  21  * @param $name
  22  *   The name of the object being stored.
  23  * @param $skip_cache
  24  *   Skip the memory cache, meaning this must be read from the db again.
  25  * @param $sid
  26  *   The session id, allowing someone to use Session API or their own solution;
  27  *   defaults to session_id().
  28  *
  29  * @deprecated $skip_cache is deprecated in favor of drupal_static*
  30  * @return
  31  *   The data that was cached.
  32  */
  33 function ctools_object_cache_get($obj, $name, $skip_cache = FALSE, $sid = NULL) {
  34   $cache = &drupal_static(__FUNCTION__, array());
  35   $key = "$obj:$name";
  36   if ($skip_cache) {
  37     unset($cache[$key]);
  38   }
  39
  40   if (!$sid) {
  41     $sid = session_id();
  42   }
  43
  44   if (!array_key_exists($key, $cache)) {
  45     $data = db_query('SELECT * FROM {ctools_object_cache} WHERE sid = :session_id AND obj = :object AND name = :name', array(':session_id' => $sid, ':object' => $obj, ':name' => $name))
  46       ->fetchObject();
  47     if ($data) {
  48       $cache[$key] = unserialize($data->data);
  49     }
  50   }
  51   return isset($cache[$key]) ? $cache[$key] : NULL;
  52 }
  53
  54 /**
  55  * Store an object in the non-volatile ctools cache.
  56  *
  57  * @param $obj
  58  *   A 128 character or less string to define what kind of object is being
  59  *   stored; primarily this is used to prevent collisions.
  60  * @param $name
  61  *   The name of the object being stored.
  62  * @param $cache
  63  *   The object to be cached. This will be serialized prior to writing.
  64  * @param $sid
  65  *   The session id, allowing someone to use Session API or their own solution;
  66  *   defaults to session_id().
  67  */
  68 function ctools_object_cache_set($obj, $name, $cache, $sid = NULL) {
  69   // Store the CTools session id in the user session to force a
  70   // session for anonymous users in Drupal 7 and Drupal 6 Pressflow.
  71   // see http://drupal.org/node/562374, http://drupal.org/node/861778
  72   if (empty($GLOBALS['user']->uid) && empty($_SESSION['ctools_session_id'])) {
  73     $_SESSION['ctools_hold_session'] = TRUE;
  74   }
  75
  76   ctools_object_cache_clear($obj, $name, $sid);
  77
  78   if (!$sid) {
  79     $sid = session_id();
  80   }
  81
  82   db_insert('ctools_object_cache')
  83     ->fields(array(
  84       'sid' => $sid,
  85       'obj' => $obj,
  86       'name' => $name,
  87       'data' => serialize($cache),
  88       'updated' => REQUEST_TIME,
  89     ))
  90     ->execute();
  91 }
  92
  93 /**
  94  * Remove an object from the non-volatile ctools cache
  95  *
  96  * @param $obj
  97  *   A 128 character or less string to define what kind of object is being
  98  *   stored; primarily this is used to prevent collisions.
  99  * @param $name
 100  *   The name of the object being removed.
 101  * @param $sid
 102  *   The session id, allowing someone to use Session API or their own solution;
 103  *   defaults to session_id().
 104  */
 105 function ctools_object_cache_clear($obj, $name, $sid = NULL) {
 106
 107   if (!$sid) {
 108     $sid = session_id();
 109   }
 110
 111   db_delete('ctools_object_cache')
 112     ->condition('sid', $sid)
 113     ->condition('obj', $obj)
 114     ->condition('name', $name)
 115     ->execute();
 116   // Ensure the static cache is emptied of this obj:name set.
 117   drupal_static_reset('ctools_object_cache_get');
 118 }
 119
 120
 121 /**
 122  * Determine if another user has a given object cached.
 123  *
 124  * This is very useful for 'locking' objects so that only one user can
 125  * modify them.
 126  *
 127  * @param $obj
 128  *   A 128 character or less string to define what kind of object is being
 129  *   stored; primarily this is used to prevent collisions.
 130  * @param $name
 131  *   The name of the object being removed.
 132  * @param $sid
 133  *   The session id, allowing someone to use Session API or their own solution;
 134  *   defaults to session_id().
 135  *
 136  * @return
 137  *   An object containing the UID and updated date if found; NULL if not.
 138  */
 139 function ctools_object_cache_test($obj, $name, $sid = NULL) {
 140
 141   if (!$sid) {
 142     $sid = session_id();
 143   }
 144
 145   return db_query('SELECT s.uid, c.updated FROM {ctools_object_cache} c INNER JOIN {sessions} s ON c.sid = s.sid WHERE s.sid <> :session_id AND c.obj = :obj AND c.name = :name ORDER BY c.updated ASC', array(':session_id' => $sid, ':obj' => $obj, ':name' => $name))
 146     ->fetchObject();
 147 }
 148
 149 /**
 150  * Get the cache status of a group of objects.
 151  *
 152  * This is useful for displaying lock status when listing a number of objects
 153  * an an administration UI.
 154  *
 155  * @param $obj
 156  *   A 128 character or less string to define what kind of object is being
 157  *   stored; primarily this is used to prevent collisions.
 158  * @param $names
 159  *   An array of names of objects
 160  *
 161  * @return
 162  *   An array of objects containing the UID and updated date for each name found.
 163  */
 164 function ctools_object_cache_test_objects($obj, $names) {
 165   return db_query("SELECT c.name, s.uid, c.updated FROM {ctools_object_cache} c INNER JOIN {sessions} s ON c.sid = s.sid WHERE c.obj = :obj AND c.name IN (:names) ORDER BY c.updated ASC", array(':obj' => $obj, ':names' => $names))
 166     ->fetchAllAssoc('name');
 167 }
 168
 169 /**
 170  * Remove an object from the non-volatile ctools cache for all session IDs.
 171  *
 172  * This is useful for clearing a lock.
 173  *
 174  * @param $obj
 175  *   A 128 character or less string to define what kind of object is being
 176  *   stored; primarily this is used to prevent collisions.
 177  * @param $name
 178  *   The name of the object being removed.
 179  */
 180 function ctools_object_cache_clear_all($obj, $name) {
 181   db_delete('ctools_object_cache')
 182     ->condition('obj', $obj)
 183     ->condition('name', $name)
 184     ->execute();
 185   // Ensure the static cache is emptied of this obj:name set.
 186   $cache = &drupal_static('ctools_object_cache_get', array());
 187   unset($cache["$obj:$name"]);
 188 }
 189
 190 /**
 191  * Remove all objects in the object cache that are older than the
 192  * specified age.
 193  *
 194  * @param $age
 195  *   The minimum age of objects to remove, in seconds. For example, 86400 is
 196  *   one day. Defaults to 7 days.
 197  */
 198 function ctools_object_cache_clean($age = NULL) {
 199   if (empty($age)) {
 200     $age = 86400 * 7; // 7 days
 201   }
 202   db_delete('ctools_object_cache')
 203     ->condition('updated', REQUEST_TIME - $age, '<')
 204     ->execute();
 205 }