Fixes #3940. Cleaned up caching for access functions. Access caches are now cleared on ignore access change.

3 files changed, 120 insertions, 59 deletions

diff --git a/engine/classes/ElggStaticVariableCache.php b/engine/classes/ElggStaticVariableCache.php
index 787d35a32..17d849400 100644
--- a/engine/classes/ElggStaticVariableCache.php
+++ b/engine/classes/ElggStaticVariableCache.php
@@ -21,8 +21,8 @@ class ElggStaticVariableCache extends ElggSharedMemoryCache {
 	 * This function creates a variable cache in a static variable in
 	 * memory, optionally with a given namespace (to avoid overlap).
 	 *
-	 * @param string $namespace The namespace for this cache to write to
-	 * note, namespaces of the same name are shared!
+	 * @param string $namespace The namespace for this cache to write to.
+	 * @note namespaces of the same name are shared!
 	 */
 	function __construct($namespace = 'default') {
 		$this->setNamespace($namespace);
diff --git a/engine/lib/access.php b/engine/lib/access.php
index 3b2b7aeaa..f7d3bf7ea 100644
--- a/engine/lib/access.php
+++ b/engine/lib/access.php
@@ -12,6 +12,26 @@
  */
 
 /**
+ * Return an ElggCache static variable cache for the access caches
+ *
+ * @staticvar ElggStaticVariableCache $access_cache
+ * @return \ElggStaticVariableCache
+ * @access private
+ */
+function _elgg_get_access_cache() {
+	/**
+	 * A default filestore cache using the dataroot.
+	 */
+	static $access_cache;
+
+	if (!$access_cache) {
+		$access_cache = new ElggStaticVariableCache('access');
+	}
+
+	return $access_cache;
+}
+
+/**
  * Return a string of access_ids for $user_id appropriate for inserting into an SQL IN clause.
  *
  * @uses get_access_array
@@ -29,10 +49,10 @@
  */
 function get_access_list($user_id = 0, $site_id = 0, $flush = false) {
 	global $CONFIG, $init_finished;
-	static $access_list;
-
-	if (!isset($access_list)) {
-		$access_list = array();
+	$cache = _elgg_get_access_cache();
+	
+	if ($flush) {
+		$cache->clear();
 	}
 
 	if ($user_id == 0) {
@@ -45,20 +65,20 @@ function get_access_list($user_id = 0, $site_id = 0, $flush = false) {
 	$user_id = (int) $user_id;
 	$site_id = (int) $site_id;
 
-	if (isset($access_list[$user_id]) && $flush == false) {
-		return $access_list[$user_id];
-	}
+	$hash = $user_id . $site_id . 'get_access_list';
 
-	$access = "(" . implode(",", get_access_array($user_id, $site_id, $flush)) . ")";
+	if ($cache[$hash]) {
+		return $cache[$hash];
+	}
+	
+	$access_array = get_access_array($user_id, $site_id, $flush);
+	$access = "(" . implode(",", $access_array) . ")";
 
-	// only cache if done with init and access is enabled (unless admin user)
-	// session is loaded before init is finished, so don't need to check for user session
-	if ($init_finished && (elgg_is_admin_logged_in() || !elgg_get_ignore_access())) {
-		$access_list[$user_id] = $access;
-		return $access_list[$user_id];
-	} else {
-		return $access;
+	if ($init_finished) {
+		$cache[$hash] = $access;
 	}
+	
+	return $access;
 }
 
 /**
@@ -86,9 +106,11 @@ function get_access_list($user_id = 0, $site_id = 0, $flush = false) {
 function get_access_array($user_id = 0, $site_id = 0, $flush = false) {
 	global $CONFIG, $init_finished;
 
-	// @todo everything from the db is cached.
-	// this cache might be redundant. But db cache is flushed on every db write.
-	static $access_array = array();
+	$cache = _elgg_get_access_cache();
+
+	if ($flush) {
+		$cache->clear();
+	}
 
 	if ($user_id == 0) {
 		$user_id = elgg_get_logged_in_user_guid();
@@ -101,35 +123,41 @@ function get_access_array($user_id = 0, $site_id = 0, $flush = false) {
 	$user_id = (int) $user_id;
 	$site_id = (int) $site_id;
 
-	if (empty($access_array[$user_id]) || $flush == true) {
-		$tmp_access_array = array(ACCESS_PUBLIC);
+	$hash = $user_id . $site_id . 'get_access_array';
+
+	if ($cache[$hash]) {
+		$access_array = $cache[$hash];
+	} else {
+		$access_array = array(ACCESS_PUBLIC);
 
 		// The following can only return sensible data if the user is logged in.
 		if (elgg_is_logged_in()) {
-			$tmp_access_array[] = ACCESS_LOGGED_IN;
+			$access_array[] = ACCESS_LOGGED_IN;
 
 			// Get ACL memberships
 			$query = "SELECT am.access_collection_id"
 				. " FROM {$CONFIG->dbprefix}access_collection_membership am"
 				. " LEFT JOIN {$CONFIG->dbprefix}access_collections ag ON ag.id = am.access_collection_id"
-				. " WHERE am.user_guid = {$user_id} AND (ag.site_guid = {$site_id} OR ag.site_guid = 0)";
+				. " WHERE am.user_guid = $user_id AND (ag.site_guid = $site_id OR ag.site_guid = 0)";
 
-			if ($collections = get_data($query)) {
+			$collections = get_data($query);
+			if ($collections) {
 				foreach ($collections as $collection) {
 					if (!empty($collection->access_collection_id)) {
-						$tmp_access_array[] = (int)$collection->access_collection_id;
+						$access_array[] = (int)$collection->access_collection_id;
 					}
 				}
 			}
 
 			// Get ACLs owned.
 			$query = "SELECT ag.id FROM {$CONFIG->dbprefix}access_collections ag ";
-			$query .= "WHERE ag.owner_guid = {$user_id} AND (ag.site_guid = {$site_id} OR ag.site_guid = 0)";
+			$query .= "WHERE ag.owner_guid = $user_id AND (ag.site_guid = $site_id OR ag.site_guid = 0)";
 
-			if ($collections = get_data($query)) {
+			$collections = get_data($query);
+			if ($collections) {
 				foreach ($collections as $collection) {
 					if (!empty($collection->id)) {
-						$tmp_access_array[] = (int)$collection->id;
+						$access_array[] = (int)$collection->id;
 					}
 				}
 			}
@@ -137,21 +165,21 @@ function get_access_array($user_id = 0, $site_id = 0, $flush = false) {
 			$ignore_access = elgg_check_access_overrides($user_id);
 
 			if ($ignore_access == true) {
-				$tmp_access_array[] = ACCESS_PRIVATE;
+				$access_array[] = ACCESS_PRIVATE;
 			}
+		}
 
-			// only cache if done with init and access is enabled (unless admin user)
-			// session is loaded before init is finished, so don't need to check for user session
-			if ($init_finished && (elgg_is_admin_logged_in() || !elgg_get_ignore_access())) {
-				$access_array[$user_id] = $tmp_access_array;
-			}
+		if ($init_finished) {
+			$cache[$hash] = $access_array;
 		}
-	} else {
-		$tmp_access_array = $access_array[$user_id];
 	}
 
-	$options = array('user_id' => $user_id, 'site_id' => $site_id);
-	return elgg_trigger_plugin_hook('access:collections:read', 'user', $options, $tmp_access_array);
+	$options = array(
+		'user_id' => $user_id,
+		'site_id' => $site_id
+	);
+	
+	return elgg_trigger_plugin_hook('access:collections:read', 'user', $options, $access_array);
 }
 
 /**
@@ -397,9 +425,12 @@ function has_access_to_entity($entity, $user = null) {
  * @link http://docs.elgg.org/Access
  */
 function get_write_access_array($user_id = 0, $site_id = 0, $flush = false) {
-	global $CONFIG;
-	//@todo this is probably not needed since caching happens at the DB level.
-	static $access_array;
+	global $CONFIG, $init_finished;
+	$cache = _elgg_get_access_cache();
+
+	if ($flush) {
+		$cache->clear();
+	}
 
 	if ($user_id == 0) {
 		$user_id = elgg_get_logged_in_user_guid();
@@ -412,37 +443,41 @@ function get_write_access_array($user_id = 0, $site_id = 0, $flush = false) {
 	$user_id = (int) $user_id;
 	$site_id = (int) $site_id;
 
-	if (empty($access_array[$user_id]) || $flush == true) {
-		$query = "SELECT ag.* FROM {$CONFIG->dbprefix}access_collections ag ";
-		$query .= " WHERE (ag.site_guid = {$site_id} OR ag.site_guid = 0)";
-		$query .= " AND (ag.owner_guid = {$user_id})";
-		// ACCESS_PRIVATE through ACCESS_PUBLIC take 0 through 2
-		// @todo this AND clause is unnecessary because of id starts at 3 for table
-		$query .= " AND ag.id >= 3";
+	$hash = $user_id . $site_id . 'get_write_access_array';
 
-		$tmp_access_array = array(
+	if ($cache[$hash]) {
+		$access_array = $cache[$hash];
+	} else {
+		// @todo is there such a thing as public write access?
+		$access_array = array(
 			ACCESS_PRIVATE => elgg_echo("PRIVATE"),
 			ACCESS_FRIENDS => elgg_echo("access:friends:label"),
 			ACCESS_LOGGED_IN => elgg_echo("LOGGED_IN"),
 			ACCESS_PUBLIC => elgg_echo("PUBLIC")
 		);
+		
+		$query = "SELECT ag.* FROM {$CONFIG->dbprefix}access_collections ag ";
+		$query .= " WHERE (ag.site_guid = $site_id OR ag.site_guid = 0)";
+		$query .= " AND (ag.owner_guid = $user_id)";
+
 		$collections = get_data($query);
 		if ($collections) {
 			foreach ($collections as $collection) {
-				$tmp_access_array[$collection->id] = $collection->name;
+				$access_array[$collection->id] = $collection->name;
 			}
 		}
 
-		$access_array[$user_id] = $tmp_access_array;
-	} else {
-		$tmp_access_array = $access_array[$user_id];
+		if ($init_finished) {
+			$cache[$hash] = $access_array;
+		}
 	}
 
-	$options = array('user_id' => $user_id, 'site_id' => $site_id);
-	$tmp_access_array = elgg_trigger_plugin_hook('access:collections:write', 'user',
-		$options, $tmp_access_array);
-
-	return $tmp_access_array;
+	$options = array(
+		'user_id' => $user_id,
+		'site_id' => $site_id
+	);
+	return elgg_trigger_plugin_hook('access:collections:write', 'user',
+		$options, $access_array);
 }
 
 /**
@@ -871,6 +906,8 @@ function get_readable_access_level($entity_access_id) {
  * @tip Use this to access entities in automated scripts
  * when no user is logged in.
  *
+ * @note This clears the access cache.
+ *
  * @warning This will not show disabled entities.
  * Use {@link access_show_hidden_entities()} to access disabled entities.
  *
@@ -882,6 +919,8 @@ function get_readable_access_level($entity_access_id) {
  * @see elgg_get_ignore_access()
  */
 function elgg_set_ignore_access($ignore = true) {
+	$cache = _elgg_get_access_cache();
+	$cache->clear();
 	$elgg_access = elgg_get_access_object();
 	return $elgg_access->setIgnoreAccess($ignore);
 }
diff --git a/engine/tests/api/access_collections.php b/engine/tests/api/access_collections.php
index bea995a6e..ebcd7d318 100644
--- a/engine/tests/api/access_collections.php
+++ b/engine/tests/api/access_collections.php
@@ -268,4 +268,26 @@ class ElggCoreAccessCollectionsTest extends ElggCoreUnitTest {
 
 		$group->delete();
 	}
+
+	public function testAccessCaching() {
+		// create a new user to check against
+		$user = new ElggUser();
+		$user->username = 'access_test_user';
+		$user->save();
+
+		foreach (array('get_access_list', 'get_access_array') as $func) {
+			$cache = _elgg_get_access_cache();
+			$cache->clear();
+
+			// admin users run tests, so disable access
+			elgg_set_ignore_access(true);
+			$access = $func($user->getGUID());
+
+			elgg_set_ignore_access(false);
+			$access2 = $func($user->getGUID());
+			$this->assertNotEqual($access, $access2, "Access test for $func");
+		}
+
+		$user->delete();	
+	}
 }