From 332aed88eb317410a9ef02766fbdc4e6ee4e3675 Mon Sep 17 00:00:00 2001
From: Olav Morken <olav.morken@uninett.no>
Date: Wed, 14 May 2008 11:06:30 +0000
Subject: [PATCH] Changed MemcacheStore to use the Memcache class.
git-svn-id: https://simplesamlphp.googlecode.com/svn/trunk@558 44740490-163a-0410-bde0-09ae8108e29a
---
lib/SimpleSAML/MemcacheStore.php | 560 ++++---------------------------
1 file changed, 59 insertions(+), 501 deletions(-)
diff --git a/lib/SimpleSAML/MemcacheStore.php b/lib/SimpleSAML/MemcacheStore.php
index 90c7cd1d9..1cc9206f8 100644
--- a/lib/SimpleSAML/MemcacheStore.php
+++ b/lib/SimpleSAML/MemcacheStore.php
@@ -1,31 +1,12 @@
<?php
-/* We need access to the configuration from config/config.php. */
-require_once((isset($SIMPLESAML_INCPREFIX)?$SIMPLESAML_INCPREFIX:'') . 'SimpleSAML/Configuration.php');
-
-/* For access to SimpleSAML_Utilities::transposeArray. */
require_once((isset($SIMPLESAML_INCPREFIX)?$SIMPLESAML_INCPREFIX:'') . 'SimpleSAML/Utilities.php');
-
-/* For the interface that objects can export to allow us to see if it
- * is modified or not.
- */
require_once((isset($SIMPLESAML_INCPREFIX)?$SIMPLESAML_INCPREFIX:'') . 'SimpleSAML/ModifiedInfo.php');
+require_once((isset($SIMPLESAML_INCPREFIX)?$SIMPLESAML_INCPREFIX:'') . 'SimpleSAML/Memcache.php');
-/*
- * This file is part of SimpleSAMLphp. See the file COPYING in the
- * root of the distribution for licence information.
- *
- * This file implements a storage class which stores data to one or more
- * groups memcache servers.
- *
- * The goals of this storage class is to provide failover, redudancy and load
- * balancing. This is accomplished by storing the data object to several
- * groups of memcache servers. Each data object is replicated to every group
- * of memcache servers, but it is only stored to one server in each group.
- *
- * For this code to work correctly, all web servers accessing the data must
- * have the same clock (as measured by the time()-function). Different clock
- * values will lead to incorrect behaviour.
+/**
+ * This class provides a class with behaviour similar to the $_SESSION variable.
+ * Data is automatically saved on exit.
*
* @author Olav Morken, UNINETT AS.
* @package simpleSAMLphp
@@ -34,23 +15,16 @@ require_once((isset($SIMPLESAML_INCPREFIX)?$SIMPLESAML_INCPREFIX:'') . 'SimpleSA
class SimpleSAML_MemcacheStore {
- /* This variable contains the last commit time of this object.
- * This is used to determine which of the memcache servers contain
- * the newest version.
- *
- * This variable is serialized.
- */
- private $lastCommitTime = NULL;
-
-
- /* This variable contains the id for this data.
+ /**
+ * This variable contains the id for this data.
*
* This variable is serialized.
*/
private $id = NULL;
- /* This variable contains an array with all key-value pairs stored
+ /**
+ * This variable contains an array with all key-value pairs stored
* in this object.
*
* This variable is serialized.
@@ -58,7 +32,8 @@ class SimpleSAML_MemcacheStore {
private $data = NULL;
- /* This variable contains the serialized data which is currently
+ /**
+ * This variable contains the serialized data which is currently
* stored on the memcache servers. By comparing the data which is
* stored against the current data, we can determine whether we
* should update the data.
@@ -71,115 +46,47 @@ class SimpleSAML_MemcacheStore {
private $savedData = NULL;
- /* Private cache of the memcache servers we are using. */
- private static $serverGroups = NULL;
-
-
- /* This function is used to find an existing storage object. It will
- * return NULL if no storage object with the given id is found.
- *
- * Parameters:
- * $id The id of the storage object we are looking for. A id
- * consists of lowercase alphanumeric characters.
+ /**
+ * This function is used to find an existing storage object. It will return NULL if no storage object
+ * with the given id is found.
*
- * Returns:
- * The corresponding MemcacheStorage object if the data is found
- * or NULL if it isn't found.
+ * @param $id The id of the storage object we are looking for. A id consists of lowercase
+ * alphanumeric characters.
+ * @return The corresponding MemcacheStorage object if the data is found or NULL if it isn't found.
*/
public static function find($id) {
assert(self::isValidID($id));
- $mustUpdate = FALSE;
- $latest = NULL;
- $latestSerializedValue = NULL;
+ $serializedData = SimpleSAML_Memcache::get($id);
+ $data = unserialize($serializedData);
- /* Search all the servers for the given id. */
- foreach(self::getMemcacheServers() as $server) {
- $serializedValue = $server->get($id);
- if($serializedValue === FALSE) {
- /* Either the server is down, or we don't have
- * the value stored on that server.
- */
- $mustUpdate = TRUE;
- continue;
- }
-
- /* Deserialize the object. */
- $v = unserialize($serializedValue);
-
- /* Make sure that the deserialized object is of the
- * correct type.
- */
- if(!($v instanceof self)) {
- $e = 'We retrieved an object from the' .
- ' memcache server which wasn\'t an' .
- ' instance of a MemcacheStore object.' .
- ' This should never happen, and is a ' .
- ' sign that the MemcacheStore may be ' .
- ' unreliable.';
- error_log($e);
- die($e);
- }
-
- if($latest === NULL) {
- $latest = $v;
- $latestSerializedValue = $serializedValue;
- continue;
- }
-
- if($latest->lastCommitTime == $v->lastCommitTime) {
- /* They were committed at the same time. Assume
- * that they are equal.
- */
- continue;
- }
-
- /* They are different. We need to update at least one
- * of them to maintain synchronization.
- */
-
- $mustUpdate = TRUE;
-
- /* Update $latest if $v is newer than $latest. */
- if($latest->lastCommitTime < $v->lastCommitTime) {
- $latest = $v;
- $latestSerializedValue = $serializedValue;
- }
+ if($data === NULL) {
+ return $NULL;
}
- /* Check if we found any stored object matching the id. */
- if($latest === NULL) {
+ if(!($data instanceof self)) {
+ error_log('Retrieved key from memcache did not contain a MemcacheStore object.');
return NULL;
}
- /* If we don't need to update this data object, then we can
- * store the serialized value in the MemcacheStore object. If
- * we need to update this object, then we don't store the
- * serialized value.
- */
- if($mustUpdate === FALSE) {
- $latest->savedData = $latestSerializedValue;
- }
+ $data->savedData = $serializedData;
/* Add a call to save the data when we exit. */
- register_shutdown_function(array($latest, 'save'));
+ register_shutdown_function(array($data, 'save'));
- return $latest;
+ return $data;
}
- /* This constructor is used to create a new storage object. The storage
- * object will be created with the specified id and the initial
- * content passed in the data argument.
+ /**
+ * This constructor is used to create a new storage object. The storage object will be created with the
+ * specified id and the initial content passed in the data argument.
*
- * If there exists a storage object with the specified id, then it will
- * be overwritten.
+ * If there exists a storage object with the specified id, then it will be overwritten.
*
- * Parameters:
- * $id The id of the storage object.
- * $data An array containing the initial data of the storage
- * object.
+ * @param $id The id of the storage object.
+ * @param $data An array containing the initial data of the storage object.
*/
public function __construct($id, $data = array()) {
/* Validate arguments. */
@@ -194,22 +101,22 @@ class SimpleSAML_MemcacheStore {
}
- /* This magic function is called on serialization of this class.
- * It returns a list of the names of the variables which should be
- * serialized.
+ /**
+ * This magic function is called on serialization of this class. It returns a list of the names of the
+ * variables which should be serialized.
+ *
+ * @return List of variables which should be serialized.
*/
private function __sleep() {
- return array('lastCommitTime', 'id', 'data');
+ return array('id', 'data');
}
- /* This function retrieves the specified key from this storage object.
- *
- * Parameters:
- * $key The key we should retrieve the value of.
+ /**
+ * This function retrieves the specified key from this storage object.
*
- * Returns:
- * The value of the specified key, or NULL of the key wasn't found.
+ * @param $key The key we should retrieve the value of.
+ * @return The value of the specified key, or NULL of the key wasn't found.
*/
public function get($key) {
if(!array_key_exists($key, $this->data)) {
@@ -220,12 +127,12 @@ class SimpleSAML_MemcacheStore {
}
- /* This function sets the specified key to the specified value in this
+ /**
+ * This function sets the specified key to the specified value in this
* storage object.
*
- * Parameters:
- * $key The key we should set.
- * $value The value we should set the key to.
+ * @param $key The key we should set.
+ * @param $value The value we should set the key to.
*/
public function set($key, $value) {
$this->data[$key] = $value;
@@ -238,15 +145,15 @@ class SimpleSAML_MemcacheStore {
}
- /* This function determines whether we need to update the data which
+ /**
+ * This function determines whether we need to update the data which
* is stored on the memcache servers.
*
* If we are unable to detect a change, then we will serialize the
* class and compare this to the data we have cached. We do this to
* determine if any of the references have changed.
*
- * Returns:
- * TRUE if this object needs an update, FALSE if not.
+ * @return TRUE if this object needs an update, FALSE if not.
*/
private function needUpdate() {
/* If $savedData is NULL, then we don't have any data stored
@@ -308,299 +215,35 @@ class SimpleSAML_MemcacheStore {
return FALSE;
}
- /* We need to store the updated value to the servers. */
return TRUE;
}
- /* This function stores this storage object to the memcache servers.
+ /**
+ * This function stores this storage object to the memcache servers.
*/
public function save() {
/* First, chech whether we need to store new data. */
if(!$this->needUpdate()) {
- /* This object is unchanged - we don't need to
- * commit.
- */
+ /* This object is unchanged - we don't need to commit. */
return;
}
- /* Update the last-commit timestamp. */
- $this->lastCommitTime = time();
-
- /* Calculate the value we should store on the servers. */
+ /* Serialize this object. */
$this->savedData = serialize($this);
- /* Store this object to all groups of memcache servers. */
- foreach(self::getMemcacheServers() as $server) {
- $server->set($this->id, $this->savedData, 0,
- self::getExpireTime());
- }
- }
-
-
- /* This function adds a server from the 'memcache_store.servers'
- * configuration option to a Memcache object.
- *
- * Parameters:
- * $memcache The Memcache object we should add this server to.
- * $server The server we should parse. This is an array with
- * the following keys:
- * - hostname
- * Hostname or ip address to the memcache server.
- * - port (optional)
- * port number the memcache server is running on. This
- * defaults to memcache.default_port if no value is given.
- * The default value of memcache.default_port is 11211.
- * - weight (optional)
- * The weight of this server in the load balancing
- * cluster.
- * - timeout (optional)
- * The timeout for contacting this server, in seconds.
- * The default value is 3 seconds.
- */
- private static function addMemcacheServer($memcache, $server) {
-
- /* The hostname option is required. */
- if(!array_key_exists('hostname', $server)) {
- $e = 'hostname setting missing from server in the' .
- ' \'memcache_store.servers\' configuration' .
- ' option.';
- error_log($e);
- die($e);
- }
-
- $hostname = $server['hostname'];
-
- /* The hostname must be a valid string. */
- if(!is_string($hostname)) {
- $e = 'Invalid hostname for server in the' .
- ' \'memcache_store.servers\' configuration' .
- ' option. The hostname is supposed to be a' .
- ' string.';
- error_log($e);
- die($e);
- }
-
- /* Check if the user has specified a port number. */
- if(array_key_exists('port', $server)) {
- /* Get the port number from the array, and validate
- * it.
- */
- $port = (int)$server['port'];
- if(($port < 0) || ($port > 65535)) {
- $e = 'Invalid port for server in the' .
- ' \'memcache_store.servers\'' .
- ' configuration option. The port number' .
- ' is supposed to be an integer between' .
- ' 0 and 65535.';
- error_log($e);
- die($e);
- }
- } else {
- /* Use the default port number from the ini-file. */
- $port = (int)ini_get('memcache.default_port');
- if($port <= 0 || $port > 65535) {
- /* Invalid port number from the ini-file.
- * fall back to the default.
- */
- $port = 11211;
- }
- }
-
- /* Check if the user has specified a weight for this server. */
- if(array_key_exists('weight', $server)) {
- /* Get the weight and validate it. */
- $weight = (int)$server['weight'];
- if($weight <= 0) {
- $e = 'Invalid weight for server in the' .
- ' \'memcache_store.servers\'' .
- ' configuration option. The weight is' .
- ' supposed to be a positive integer.';
- error_log($e);
- die($e);
- }
- } else {
- /* Use a default weight of 1. */
- $weight = 1;
- }
-
- /* Check if the user has specified a timeout for this
- * server.
- */
- if(array_key_exists('timeout', $server)) {
- /* Get the timeout and validate it. */
- $timeout = (int)$server['timeout'];
- if($timeout <= 0) {
- $e = 'Invalid timeout for server in the' .
- ' \'memcache_store.servers\'' .
- ' configuration option. The timeout is' .
- ' supposed to be a positive integer.';
- error_log($e);
- die($e);
- }
- } else {
- /* Use a default timeout of 3 seconds. */
- $timeout = 3;
- }
-
- /* Add this server to the Memcache object. */
- $memcache->addServer($hostname, $port, TRUE, $weight, $timeout);
- }
-
-
- /* This function takes in a list of servers belonging to a group and
- * creates a Memcache object from the servers in the group.
- *
- * Parameters:
- * $group Array of servers. Each server is represented by one array
- * with the hostname (and optionally port number, timeout,
- * ...). See the addMemcacheServer function for more
- * information.
- *
- * Returns:
- * A Memcache object of the servers in the group.
- */
- private static function loadMemcacheServerGroup($group) {
- /* Create the Memcache object. */
- $memcache = new Memcache();
- if($memcache == NULL) {
- $e = 'Unable to create an instance of a Memcache' .
- ' object. Is the memcache extension' .
- ' installed?';
- error_log($e);
- die($e);
- }
-
- /* Iterate over all the servers in the group and add them to
- * the Memcache object.
- */
- foreach($group as $index => $server) {
- /* Make sure that we don't have an index. An index
- * would be a sign of invalid configuration.
- */
- if(!is_int($index)) {
- $e = 'Invalid index on element in the' .
- ' \'memcache_store.servers\'' .
- ' configuration option. Perhaps you' .
- ' have forgotten to add an array(...)' .
- ' around one of the server groups? The' .
- ' invalid index was: ' . $index;
- error_log($e);
- die($e);
- }
-
- /* Make sure that the server object is an array. Each
- * server is an array with name-value pairs.
- */
- if(!is_array($server)) {
- $e = 'Invalid value for the server with' .
- ' index ' . $index . '. Remeber that' .
- ' the \'memcache_store.servers\'' .
- ' configuration option contains an' .
- ' array of arrays of arrays.';
- error_log($e);
- die($e);
- }
-
- self::addMemcacheServer($memcache, $server);
- }
-
- return $memcache;
- }
-
-
- /* This function gets a list of all configured memcache servers. This
- * list is initialized based on the content of
- * 'memcache_store.servers' in the configuration.
- *
- * Returns:
- * Array with Memcache objects.
- */
- private static function getMemcacheServers() {
-
- /* Check if we have loaded the servers already. */
- if(self::$serverGroups != NULL) {
- return self::$serverGroups;
- }
-
- /* Initialize the servers-array. */
- self::$serverGroups = array();
-
- /* Load the configuration. */
- $config = SimpleSAML_Configuration::getInstance();
- assert($config instanceof SimpleSAML_Configuration);
-
-
- $groups = $config->getValue('memcache_store.servers');
-
- /* Validate the 'memcache_store.servers' configuration
- * option.
- */
- if(is_null($groups)) {
- $e = 'Unable to get value of the' .
- ' \'memcache_store.servers\' configuration' .
- ' option.';
- error_log($e);
- die($e);
- }
- if(!is_array($groups)) {
- $e = 'The value of the \'memcache_store.servers\'' .
- ' configuration option isn\'t an array.';
- error_log($e);
- die($e);
- }
-
- /* Iterate over all the groups in the
- * 'memcache_store.servers' configuration option.
- */
- foreach($groups as $index => $group) {
- /* Make sure that the group doesn't have an index.
- * An index would be a sign of invalid configuration.
- */
- if(!is_int($index)) {
- $e = 'Invalid index on element in the' .
- ' \'memcache_store.servers\'' .
- ' configuration option. Perhaps you' .
- ' have forgotten to add an array(...)' .
- ' around one of the server groups? The' .
- ' invalid index was: ' . $index;
- error_log($e);
- die($e);
- }
-
- /* Make sure that the group is an array. Each group
- * is an array of servers. Each server is an array of
- * name => value pairs for that server.
- */
- if(!is_array($group)) {
- $e = 'Invalid value for the server with' .
- ' index ' . $index . '. Remeber that' .
- ' the \'memcache_store.servers\'' .
- ' configuration option contains an' .
- ' array of arrays of arrays.';
- error_log($e);
- die($e);
- }
-
- /* Parse and add this group to the server group list.
- */
- self::$serverGroups[] =
- self::loadMemcacheServerGroup($group);
- }
-
- return self::$serverGroups;
+ /* Write to the memcache servers. */
+ SimpleSAML_Memcache::set($this->id, $this->savedData);
}
- /* This function determines whether the argument is a valid id.
+ /**
+ * This function determines whether the argument is a valid id.
* A valid id is a string containing lowercase alphanumeric
* characters.
*
- * Parameters:
- * $id The id we should validate.
- *
- * Returns:
- * TRUE if the id is valid, FALSE otherwise.
+ * @param $id The id we should validate.
+ * @return TRUE if the id is valid, FALSE otherwise.
*/
private static function isValidID($id) {
if(!is_string($id)) {
@@ -618,90 +261,5 @@ class SimpleSAML_MemcacheStore {
return TRUE;
}
-
- /* This is a helper-function which returns the expire value of data
- * we should store to the memcache servers.
- *
- * The value is set depending on the configuration. If no value is
- * set in the configuration, then we will use a default value of 0.
- * 0 means that the item will never expire.
- *
- * Returns:
- * The value which should be passed in the set(...) calls to the
- * memcache objects.
- */
- private static function getExpireTime()
- {
- /* Get the configuration instance. */
- $config = SimpleSAML_Configuration::getInstance();
- assert($config instanceof SimpleSAML_Configuration);
-
- /* Get the expire-value from the configuration. */
- $expire = $config->getValue('memcache_store.expires');
-
- /* If 'memcache_store.expires' isn't defined in the
- * configuration, then we will use 0 as the expire parameter.
- */
- if($expire === NULL) {
- return 0;
- }
-
- /* The 'memcache_store.expires' option must be an integer. */
- if(!is_integer($expire)) {
- $e = 'The value of \'memcache_store.expires\' in the' .
- ' configuration must be a valid integer.';
- error_log($e);
- die($e);
- }
-
- /* It must be a positive integer. */
- if($expire < 0) {
- $e = 'The value of \'memcache_store.expires\' in the' .
- ' configuration can\'t be a negative integer.';
- error_log($e);
- die($e);
- }
-
- /* If the configuration option is 0, then we should
- * return 0. This allows the user to specify that the data
- * shouldn't expire.
- */
- if($expire == 0) {
- return 0;
- }
-
- /* The expire option is given as the number of seconds into the
- * future an item should expire. We convert this to an actual
- * timestamp.
- */
- $expireTime = time() + $expire;
-
- return $expireTime;
- }
-
-
- /**
- * This function retrieves statistics about all memcache server groups.
- *
- * @return Array with the names of each stat and an array with the value for each
- * server group.
- */
- public static function getStats()
- {
- $ret = array();
-
- foreach(self::getMemcacheServers() as $sg) {
- $stats = $sg->getExtendedStats();
- if($stats === FALSE) {
- throw new Exception('Failed to get memcache server status.');
- }
-
- $stats = SimpleSAML_Utilities::transposeArray($stats);
-
- $ret = array_merge_recursive($ret, $stats);
- }
-
- return $ret;
- }
}
-?>
+?>
\ No newline at end of file
--
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