eventespresso / event-espresso-core

espresso.php

Indentation +80 added lines, -80 removed lines

@@ -38,103 +38,103 @@
  * @since           4.0
  */
 if (function_exists('espresso_version')) {
-    if (! function_exists('espresso_duplicate_plugin_error')) {
-        /**
-         *    espresso_duplicate_plugin_error
-         *    displays if more than one version of EE is activated at the same time
-         */
-        function espresso_duplicate_plugin_error()
-        {
-            ?>
+	if (! function_exists('espresso_duplicate_plugin_error')) {
+		/**
+		 *    espresso_duplicate_plugin_error
+		 *    displays if more than one version of EE is activated at the same time
+		 */
+		function espresso_duplicate_plugin_error()
+		{
+			?>
             <div class="error">
                 <p>
                     <?php
-                    echo esc_html__(
-                        'Can not run multiple versions of Event Espresso! One version has been automatically deactivated. Please verify that you have the correct version you want still active.',
-                        'event_espresso'
-                    ); ?>
+					echo esc_html__(
+						'Can not run multiple versions of Event Espresso! One version has been automatically deactivated. Please verify that you have the correct version you want still active.',
+						'event_espresso'
+					); ?>
                 </p>
             </div>
             <?php
-            espresso_deactivate_plugin(plugin_basename(__FILE__));
-        }
-    }
-    add_action('admin_notices', 'espresso_duplicate_plugin_error', 1);
+			espresso_deactivate_plugin(plugin_basename(__FILE__));
+		}
+	}
+	add_action('admin_notices', 'espresso_duplicate_plugin_error', 1);
 } else {
-    define('EE_MIN_PHP_VER_REQUIRED', '5.4.0');
-    if (! version_compare(PHP_VERSION, EE_MIN_PHP_VER_REQUIRED, '>=')) {
-        /**
-         * espresso_minimum_php_version_error
-         *
-         * @return void
-         */
-        function espresso_minimum_php_version_error()
-        {
-            ?>
+	define('EE_MIN_PHP_VER_REQUIRED', '5.4.0');
+	if (! version_compare(PHP_VERSION, EE_MIN_PHP_VER_REQUIRED, '>=')) {
+		/**
+		 * espresso_minimum_php_version_error
+		 *
+		 * @return void
+		 */
+		function espresso_minimum_php_version_error()
+		{
+			?>
             <div class="error">
                 <p>
                     <?php
-                    printf(
-                        esc_html__(
-                            'We\'re sorry, but Event Espresso requires PHP version %1$s or greater in order to operate. You are currently running version %2$s.%3$sIn order to update your version of PHP, you will need to contact your current hosting provider.%3$sFor information on stable PHP versions, please go to %4$s.',
-                            'event_espresso'
-                        ),
-                        EE_MIN_PHP_VER_REQUIRED,
-                        PHP_VERSION,
-                        '<br/>',
-                        '<a href="http://php.net/downloads.php">http://php.net/downloads.php</a>'
-                    );
-                    ?>
+					printf(
+						esc_html__(
+							'We\'re sorry, but Event Espresso requires PHP version %1$s or greater in order to operate. You are currently running version %2$s.%3$sIn order to update your version of PHP, you will need to contact your current hosting provider.%3$sFor information on stable PHP versions, please go to %4$s.',
+							'event_espresso'
+						),
+						EE_MIN_PHP_VER_REQUIRED,
+						PHP_VERSION,
+						'<br/>',
+						'<a href="http://php.net/downloads.php">http://php.net/downloads.php</a>'
+					);
+					?>
                 </p>
             </div>
             <?php
-            espresso_deactivate_plugin(plugin_basename(__FILE__));
-        }
+			espresso_deactivate_plugin(plugin_basename(__FILE__));
+		}
 
-        add_action('admin_notices', 'espresso_minimum_php_version_error', 1);
-    } else {
-        define('EVENT_ESPRESSO_MAIN_FILE', __FILE__);
-        /**
-         * espresso_version
-         * Returns the plugin version
-         *
-         * @return string
-         */
-        function espresso_version()
-        {
-            return apply_filters('FHEE__espresso__espresso_version', '4.9.63.rc.018');
-        }
+		add_action('admin_notices', 'espresso_minimum_php_version_error', 1);
+	} else {
+		define('EVENT_ESPRESSO_MAIN_FILE', __FILE__);
+		/**
+		 * espresso_version
+		 * Returns the plugin version
+		 *
+		 * @return string
+		 */
+		function espresso_version()
+		{
+			return apply_filters('FHEE__espresso__espresso_version', '4.9.63.rc.018');
+		}
 
-        /**
-         * espresso_plugin_activation
-         * adds a wp-option to indicate that EE has been activated via the WP admin plugins page
-         */
-        function espresso_plugin_activation()
-        {
-            update_option('ee_espresso_activation', true);
-        }
+		/**
+		 * espresso_plugin_activation
+		 * adds a wp-option to indicate that EE has been activated via the WP admin plugins page
+		 */
+		function espresso_plugin_activation()
+		{
+			update_option('ee_espresso_activation', true);
+		}
 
-        register_activation_hook(EVENT_ESPRESSO_MAIN_FILE, 'espresso_plugin_activation');
+		register_activation_hook(EVENT_ESPRESSO_MAIN_FILE, 'espresso_plugin_activation');
 
-        require_once __DIR__ . '/core/bootstrap_espresso.php';
-        bootstrap_espresso();
-    }
+		require_once __DIR__ . '/core/bootstrap_espresso.php';
+		bootstrap_espresso();
+	}
 }
 if (! function_exists('espresso_deactivate_plugin')) {
-    /**
-     *    deactivate_plugin
-     * usage:  espresso_deactivate_plugin( plugin_basename( __FILE__ ));
-     *
-     * @access public
-     * @param string $plugin_basename - the results of plugin_basename( __FILE__ ) for the plugin's main file
-     * @return    void
-     */
-    function espresso_deactivate_plugin($plugin_basename = '')
-    {
-        if (! function_exists('deactivate_plugins')) {
-            require_once ABSPATH . 'wp-admin/includes/plugin.php';
-        }
-        unset($_GET['activate'], $_REQUEST['activate']);
-        deactivate_plugins($plugin_basename);
-    }
+	/**
+	 *    deactivate_plugin
+	 * usage:  espresso_deactivate_plugin( plugin_basename( __FILE__ ));
+	 *
+	 * @access public
+	 * @param string $plugin_basename - the results of plugin_basename( __FILE__ ) for the plugin's main file
+	 * @return    void
+	 */
+	function espresso_deactivate_plugin($plugin_basename = '')
+	{
+		if (! function_exists('deactivate_plugins')) {
+			require_once ABSPATH . 'wp-admin/includes/plugin.php';
+		}
+		unset($_GET['activate'], $_REQUEST['activate']);
+		deactivate_plugins($plugin_basename);
+	}
 }

core/EE_Session.core.php

Indentation +1239 added lines, -1239 removed lines

@@ -23,1237 +23,1237 @@ 
 class EE_Session implements SessionIdentifierInterface
 {
 
-    const session_id_prefix = 'ee_ssn_';
-
-    const hash_check_prefix = 'ee_shc_';
-
-    const OPTION_NAME_SETTINGS = 'ee_session_settings';
-
-    const STATUS_CLOSED = 0;
-
-    const STATUS_OPEN = 1;
-
-    /**
-     * instance of the EE_Session object
-     *
-     * @var EE_Session
-     */
-    private static $_instance;
-
-    /**
-     * @var CacheStorageInterface $cache_storage
-     */
-    protected $cache_storage;
-
-    /**
-     * EE_Encryption object
-     *
-     * @var EE_Encryption
-     */
-    protected $encryption;
-
-    /**
-     * the session id
-     *
-     * @var string
-     */
-    private $_sid;
-
-    /**
-     * session id salt
-     *
-     * @var string
-     */
-    private $_sid_salt;
-
-    /**
-     * session data
-     *
-     * @var array
-     */
-    private $_session_data = array();
-
-    /**
-     * how long an EE session lasts
-     * default session lifespan of 1 hour (for not so instant IPNs)
-     *
-     * @var SessionLifespan $session_lifespan
-     */
-    private $session_lifespan;
-
-    /**
-     * session expiration time as Unix timestamp in GMT
-     *
-     * @var int
-     */
-    private $_expiration;
-
-    /**
-     * whether or not session has expired at some point
-     *
-     * @var boolean
-     */
-    private $_expired = false;
-
-    /**
-     * current time as Unix timestamp in GMT
-     *
-     * @var int
-     */
-    private $_time;
-
-    /**
-     * whether to encrypt session data
-     *
-     * @var bool
-     */
-    private $_use_encryption;
-
-    /**
-     * well... according to the server...
-     *
-     * @var null
-     */
-    private $_user_agent;
-
-    /**
-     * do you really trust the server ?
-     *
-     * @var null
-     */
-    private $_ip_address;
-
-    /**
-     * current WP user_id
-     *
-     * @var null
-     */
-    private $_wp_user_id;
-
-    /**
-     * array for defining default session vars
-     *
-     * @var array
-     */
-    private $_default_session_vars = array(
-        'id'            => null,
-        'user_id'       => null,
-        'ip_address'    => null,
-        'user_agent'    => null,
-        'init_access'   => null,
-        'last_access'   => null,
-        'expiration'    => null,
-        'pages_visited' => array(),
-    );
-
-    /**
-     * timestamp for when last garbage collection cycle was performed
-     *
-     * @var int $_last_gc
-     */
-    private $_last_gc;
-
-    /**
-     * @var RequestInterface $request
-     */
-    protected $request;
-
-    /**
-     * whether session is active or not
-     *
-     * @var int $status
-     */
-    private $status = EE_Session::STATUS_CLOSED;
-
-
-    /**
-     * @singleton method used to instantiate class object
-     * @param CacheStorageInterface $cache_storage
-     * @param SessionLifespan|null  $lifespan
-     * @param RequestInterface      $request
-     * @param EE_Encryption         $encryption
-     * @return EE_Session
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    public static function instance(
-        CacheStorageInterface $cache_storage = null,
-        SessionLifespan $lifespan = null,
-        RequestInterface $request = null,
-        EE_Encryption $encryption = null
-    ) {
-        // check if class object is instantiated
-        // session loading is turned ON by default, but prior to the init hook, can be turned back OFF via:
-        // add_filter( 'FHEE_load_EE_Session', '__return_false' );
-        if (! self::$_instance instanceof EE_Session && apply_filters('FHEE_load_EE_Session', true)) {
-            self::$_instance = new self(
-                $cache_storage,
-                $lifespan,
-                $request,
-                $encryption
-            );
-        }
-        return self::$_instance;
-    }
-
-
-    /**
-     * protected constructor to prevent direct creation
-     *
-     * @param CacheStorageInterface $cache_storage
-     * @param SessionLifespan       $lifespan
-     * @param RequestInterface      $request
-     * @param EE_Encryption         $encryption
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    protected function __construct(
-        CacheStorageInterface $cache_storage,
-        SessionLifespan $lifespan,
-        RequestInterface $request,
-        EE_Encryption $encryption = null
-    ) {
-        // session loading is turned ON by default,
-        // but prior to the 'AHEE__EE_System__core_loaded_and_ready' hook
-        // (which currently fires on the init hook at priority 9),
-        // can be turned back OFF via: add_filter( 'FHEE_load_EE_Session', '__return_false' );
-        if (! apply_filters('FHEE_load_EE_Session', true)) {
-            return;
-        }
-        $this->session_lifespan = $lifespan;
-        $this->request = $request;
-        if (! defined('ESPRESSO_SESSION')) {
-            define('ESPRESSO_SESSION', true);
-        }
-        // retrieve session options from db
-        $session_settings = (array) get_option(EE_Session::OPTION_NAME_SETTINGS, array());
-        if (! empty($session_settings)) {
-            // cycle though existing session options
-            foreach ($session_settings as $var_name => $session_setting) {
-                // set values for class properties
-                $var_name = '_' . $var_name;
-                $this->{$var_name} = $session_setting;
-            }
-        }
-        $this->cache_storage = $cache_storage;
-        // are we using encryption?
-        $this->_use_encryption = $encryption instanceof EE_Encryption
-                                 && EE_Registry::instance()->CFG->admin->encode_session_data();
-        // encrypt data via: $this->encryption->encrypt();
-        $this->encryption = $encryption;
-        // filter hook allows outside functions/classes/plugins to change default empty cart
-        $extra_default_session_vars = apply_filters('FHEE__EE_Session__construct__extra_default_session_vars', array());
-        array_merge($this->_default_session_vars, $extra_default_session_vars);
-        // apply default session vars
-        $this->_set_defaults();
-        add_action('AHEE__EE_System__initialize', array($this, 'open_session'));
-        // check request for 'clear_session' param
-        add_action('AHEE__EE_Request_Handler__construct__complete', array($this, 'wp_loaded'));
-        // once everything is all said and done,
-        add_action('shutdown', array($this, 'update'), 100);
-        add_action('shutdown', array($this, 'garbageCollection'), 1000);
-        $this->configure_garbage_collection_filters();
-    }
-
-
-    /**
-     * @return bool
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    public static function isLoadedAndActive()
-    {
-        return did_action('AHEE__EE_System__core_loaded_and_ready')
-               && EE_Session::instance() instanceof EE_Session
-               && EE_Session::instance()->isActive();
-    }
-
-
-    /**
-     * @return bool
-     */
-    public function isActive()
-    {
-        return $this->status === EE_Session::STATUS_OPEN;
-    }
-
-
-    /**
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws InvalidSessionDataException
-     */
-    public function open_session()
-    {
-        // check for existing session and retrieve it from db
-        if (! $this->_espresso_session()) {
-            // or just start a new one
-            $this->_create_espresso_session();
-        }
-    }
-
-
-    /**
-     * @return bool
-     */
-    public function expired()
-    {
-        return $this->_expired;
-    }
-
-
-    /**
-     * @return void
-     */
-    public function reset_expired()
-    {
-        $this->_expired = false;
-    }
-
-
-    /**
-     * @return int
-     */
-    public function expiration()
-    {
-        return $this->_expiration;
-    }
-
-
-    /**
-     * @return int
-     */
-    public function extension()
-    {
-        return apply_filters('FHEE__EE_Session__extend_expiration__seconds_added', 10 * MINUTE_IN_SECONDS);
-    }
-
-
-    /**
-     * @param int $time number of seconds to add to session expiration
-     */
-    public function extend_expiration($time = 0)
-    {
-        $time = $time ? $time : $this->extension();
-        $this->_expiration += absint($time);
-    }
-
-
-    /**
-     * @return int
-     */
-    public function lifespan()
-    {
-        return $this->session_lifespan->inSeconds();
-    }
-
-
-    /**
-     * This just sets some defaults for the _session data property
-     *
-     * @access private
-     * @return void
-     */
-    private function _set_defaults()
-    {
-        // set some defaults
-        foreach ($this->_default_session_vars as $key => $default_var) {
-            if (is_array($default_var)) {
-                $this->_session_data[ $key ] = array();
-            } else {
-                $this->_session_data[ $key ] = '';
-            }
-        }
-    }
-
-
-    /**
-     * @retrieve  session data
-     * @access    public
-     * @return    string
-     */
-    public function id()
-    {
-        return $this->_sid;
-    }
-
-
-    /**
-     * @param \EE_Cart $cart
-     * @return bool
-     */
-    public function set_cart(EE_Cart $cart)
-    {
-        $this->_session_data['cart'] = $cart;
-        return true;
-    }
-
-
-    /**
-     * reset_cart
-     */
-    public function reset_cart()
-    {
-        do_action('AHEE__EE_Session__reset_cart__before_reset', $this);
-        $this->_session_data['cart'] = null;
-    }
-
-
-    /**
-     * @return \EE_Cart
-     */
-    public function cart()
-    {
-        return isset($this->_session_data['cart']) && $this->_session_data['cart'] instanceof EE_Cart
-            ? $this->_session_data['cart']
-            : null;
-    }
-
-
-    /**
-     * @param \EE_Checkout $checkout
-     * @return bool
-     */
-    public function set_checkout(EE_Checkout $checkout)
-    {
-        $this->_session_data['checkout'] = $checkout;
-        return true;
-    }
-
-
-    /**
-     * reset_checkout
-     */
-    public function reset_checkout()
-    {
-        do_action('AHEE__EE_Session__reset_checkout__before_reset', $this);
-        $this->_session_data['checkout'] = null;
-    }
-
-
-    /**
-     * @return \EE_Checkout
-     */
-    public function checkout()
-    {
-        return isset($this->_session_data['checkout']) && $this->_session_data['checkout'] instanceof EE_Checkout
-            ? $this->_session_data['checkout']
-            : null;
-    }
-
-
-    /**
-     * @param \EE_Transaction $transaction
-     * @return bool
-     * @throws EE_Error
-     */
-    public function set_transaction(EE_Transaction $transaction)
-    {
-        // first remove the session from the transaction before we save the transaction in the session
-        $transaction->set_txn_session_data(null);
-        $this->_session_data['transaction'] = $transaction;
-        return true;
-    }
-
-
-    /**
-     * reset_transaction
-     */
-    public function reset_transaction()
-    {
-        do_action('AHEE__EE_Session__reset_transaction__before_reset', $this);
-        $this->_session_data['transaction'] = null;
-    }
-
-
-    /**
-     * @return \EE_Transaction
-     */
-    public function transaction()
-    {
-        return isset($this->_session_data['transaction'])
-               && $this->_session_data['transaction'] instanceof EE_Transaction
-            ? $this->_session_data['transaction']
-            : null;
-    }
-
-
-    /**
-     * retrieve session data
-     *
-     * @param null $key
-     * @param bool $reset_cache
-     * @return array
-     */
-    public function get_session_data($key = null, $reset_cache = false)
-    {
-        if ($reset_cache) {
-            $this->reset_cart();
-            $this->reset_checkout();
-            $this->reset_transaction();
-        }
-        if (! empty($key)) {
-            return isset($this->_session_data[ $key ]) ? $this->_session_data[ $key ] : null;
-        }
-        return $this->_session_data;
-    }
-
-
-    /**
-     * Returns TRUE on success, FALSE on fail
-     *
-     * @param array $data
-     * @return bool
-     */
-    public function set_session_data($data)
-    {
-        // nothing ??? bad data ??? go home!
-        if (empty($data) || ! is_array($data)) {
-            EE_Error::add_error(
-                esc_html__(
-                    'No session data or invalid session data was provided.',
-                    'event_espresso'
-                ),
-                __FILE__,
-                __FUNCTION__,
-                __LINE__
-            );
-            return false;
-        }
-        foreach ($data as $key => $value) {
-            if (isset($this->_default_session_vars[ $key ])) {
-                EE_Error::add_error(
-                    sprintf(
-                        esc_html__(
-                            'Sorry! %s is a default session datum and can not be reset.',
-                            'event_espresso'
-                        ),
-                        $key
-                    ),
-                    __FILE__,
-                    __FUNCTION__,
-                    __LINE__
-                );
-                return false;
-            }
-            $this->_session_data[ $key ] = $value;
-        }
-        return true;
-    }
-
-
-    /**
-     * @initiate session
-     * @access   private
-     * @return TRUE on success, FALSE on fail
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws InvalidSessionDataException
-     */
-    private function _espresso_session()
-    {
-        do_action('AHEE_log', __FILE__, __FUNCTION__, '');
-        // check that session has started
-        if (session_id() === '') {
-            // starts a new session if one doesn't already exist, or re-initiates an existing one
-            session_start();
-        }
-        $this->status = EE_Session::STATUS_OPEN;
-        // get our modified session ID
-        $this->_sid = $this->_generate_session_id();
-        // and the visitors IP
-        $this->_ip_address = $this->request->ipAddress();
-        // set the "user agent"
-        $this->_user_agent = $this->request->userAgent();
-        // now let's retrieve what's in the db
-        $session_data = $this->_retrieve_session_data();
-        if (! empty($session_data)) {
-            // get the current time in UTC
-            $this->_time = $this->_time !== null ? $this->_time : time();
-            // and reset the session expiration
-            $this->_expiration = isset($session_data['expiration'])
-                ? $session_data['expiration']
-                : $this->_time + $this->session_lifespan->inSeconds();
-        } else {
-            // set initial site access time and the session expiration
-            $this->_set_init_access_and_expiration();
-            // set referer
-            $this->_session_data['pages_visited'][ $this->_session_data['init_access'] ] = isset($_SERVER['HTTP_REFERER'])
-                ? esc_attr($_SERVER['HTTP_REFERER'])
-                : '';
-            // no previous session = go back and create one (on top of the data above)
-            return false;
-        }
-        // now the user agent
-        if ($session_data['user_agent'] !== $this->_user_agent) {
-            return false;
-        }
-        // wait a minute... how old are you?
-        if ($this->_time > $this->_expiration) {
-            // yer too old fer me!
-            $this->_expired = true;
-            // wipe out everything that isn't a default session datum
-            $this->clear_session(__CLASS__, __FUNCTION__);
-        }
-        // make event espresso session data available to plugin
-        $this->_session_data = array_merge($this->_session_data, $session_data);
-        return true;
-    }
-
-
-    /**
-     * _get_session_data
-     * Retrieves the session data, and attempts to correct any encoding issues that can occur due to improperly setup
-     * databases
-     *
-     * @return array
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidSessionDataException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    protected function _retrieve_session_data()
-    {
-        $ssn_key = EE_Session::session_id_prefix . $this->_sid;
-        try {
-            // we're using WP's Transient API to store session data using the PHP session ID as the option name
-            $session_data = $this->cache_storage->get($ssn_key, false);
-            if (empty($session_data)) {
-                return array();
-            }
-            if (apply_filters('FHEE__EE_Session___perform_session_id_hash_check', WP_DEBUG)) {
-                $hash_check = $this->cache_storage->get(
-                    EE_Session::hash_check_prefix . $this->_sid,
-                    false
-                );
-                if ($hash_check && $hash_check !== md5($session_data)) {
-                    EE_Error::add_error(
-                        sprintf(
-                            __(
-                                'The stored data for session %1$s failed to pass a hash check and therefore appears to be invalid.',
-                                'event_espresso'
-                            ),
-                            EE_Session::session_id_prefix . $this->_sid
-                        ),
-                        __FILE__,
-                        __FUNCTION__,
-                        __LINE__
-                    );
-                }
-            }
-        } catch (Exception $e) {
-            // let's just eat that error for now and attempt to correct any corrupted data
-            global $wpdb;
-            $row = $wpdb->get_row(
-                $wpdb->prepare(
-                    "SELECT option_value FROM {$wpdb->options} WHERE option_name = %s LIMIT 1",
-                    '_transient_' . $ssn_key
-                )
-            );
-            $session_data = is_object($row) ? $row->option_value : null;
-            if ($session_data) {
-                $session_data = preg_replace_callback(
-                    '!s:(d+):"(.*?)";!',
-                    function ($match) {
-                        return $match[1] === strlen($match[2])
-                            ? $match[0]
-                            : 's:' . strlen($match[2]) . ':"' . $match[2] . '";';
-                    },
-                    $session_data
-                );
-            }
-            $session_data = maybe_unserialize($session_data);
-        }
-        // in case the data is encoded... try to decode it
-        $session_data = $this->encryption instanceof EE_Encryption
-            ? $this->encryption->base64_string_decode($session_data)
-            : $session_data;
-        if (! is_array($session_data)) {
-            try {
-                $session_data = maybe_unserialize($session_data);
-            } catch (Exception $e) {
-                $msg = esc_html__(
-                    'An error occurred while attempting to unserialize the session data.',
-                    'event_espresso'
-                );
-                $msg .= WP_DEBUG
-                    ? '<br><pre>'
-                      . print_r($session_data, true)
-                      . '</pre><br>'
-                      . $this->find_serialize_error($session_data)
-                    : '';
-                $this->cache_storage->delete(EE_Session::session_id_prefix . $this->_sid);
-                throw new InvalidSessionDataException($msg, 0, $e);
-            }
-        }
-        // just a check to make sure the session array is indeed an array
-        if (! is_array($session_data)) {
-            // no?!?! then something is wrong
-            $msg = esc_html__(
-                'The session data is missing, invalid, or corrupted.',
-                'event_espresso'
-            );
-            $msg .= WP_DEBUG
-                ? '<br><pre>' . print_r($session_data, true) . '</pre><br>' . $this->find_serialize_error($session_data)
-                : '';
-            $this->cache_storage->delete(EE_Session::session_id_prefix . $this->_sid);
-            throw new InvalidSessionDataException($msg);
-        }
-        if (isset($session_data['transaction']) && absint($session_data['transaction']) !== 0) {
-            $session_data['transaction'] = EEM_Transaction::instance()->get_one_by_ID(
-                $session_data['transaction']
-            );
-        }
-        return $session_data;
-    }
-
-
-    /**
-     * _generate_session_id
-     * Retrieves the PHP session id either directly from the PHP session,
-     * or from the $_REQUEST array if it was passed in from an AJAX request.
-     * The session id is then salted and hashed (mmm sounds tasty)
-     * so that it can be safely used as a $_REQUEST param
-     *
-     * @return string
-     */
-    protected function _generate_session_id()
-    {
-        // check if the SID was passed explicitly, otherwise get from session, then add salt and hash it to reduce length
-        if (isset($_REQUEST['EESID'])) {
-            $session_id = sanitize_text_field($_REQUEST['EESID']);
-        } else {
-            $session_id = md5(session_id() . get_current_blog_id() . $this->_get_sid_salt());
-        }
-        return apply_filters('FHEE__EE_Session___generate_session_id__session_id', $session_id);
-    }
-
-
-    /**
-     * _get_sid_salt
-     *
-     * @return string
-     */
-    protected function _get_sid_salt()
-    {
-        // was session id salt already saved to db ?
-        if (empty($this->_sid_salt)) {
-            // no?  then maybe use WP defined constant
-            if (defined('AUTH_SALT')) {
-                $this->_sid_salt = AUTH_SALT;
-            }
-            // if salt doesn't exist or is too short
-            if (strlen($this->_sid_salt) < 32) {
-                // create a new one
-                $this->_sid_salt = wp_generate_password(64);
-            }
-            // and save it as a permanent session setting
-            $this->updateSessionSettings(array('sid_salt' => $this->_sid_salt));
-        }
-        return $this->_sid_salt;
-    }
-
-
-    /**
-     * _set_init_access_and_expiration
-     *
-     * @return void
-     */
-    protected function _set_init_access_and_expiration()
-    {
-        $this->_time = time();
-        $this->_expiration = $this->_time + $this->session_lifespan->inSeconds();
-        // set initial site access time
-        $this->_session_data['init_access'] = $this->_time;
-        // and the session expiration
-        $this->_session_data['expiration'] = $this->_expiration;
-    }
-
-
-    /**
-     * @update session data  prior to saving to the db
-     * @access public
-     * @param bool $new_session
-     * @return TRUE on success, FALSE on fail
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    public function update($new_session = false)
-    {
-        $this->_session_data = $this->_session_data !== null
-                               && is_array($this->_session_data)
-                               && isset($this->_session_data['id'])
-            ? $this->_session_data
-            : array();
-        if (empty($this->_session_data)) {
-            $this->_set_defaults();
-        }
-        $session_data = array();
-        foreach ($this->_session_data as $key => $value) {
-            switch ($key) {
-                case 'id':
-                    // session ID
-                    $session_data['id'] = $this->_sid;
-                    break;
-                case 'ip_address':
-                    // visitor ip address
-                    $session_data['ip_address'] = $this->request->ipAddress();
-                    break;
-                case 'user_agent':
-                    // visitor user_agent
-                    $session_data['user_agent'] = $this->_user_agent;
-                    break;
-                case 'init_access':
-                    $session_data['init_access'] = absint($value);
-                    break;
-                case 'last_access':
-                    // current access time
-                    $session_data['last_access'] = $this->_time;
-                    break;
-                case 'expiration':
-                    // when the session expires
-                    $session_data['expiration'] = ! empty($this->_expiration)
-                        ? $this->_expiration
-                        : $session_data['init_access'] + $this->session_lifespan->inSeconds();
-                    break;
-                case 'user_id':
-                    // current user if logged in
-                    $session_data['user_id'] = $this->_wp_user_id();
-                    break;
-                case 'pages_visited':
-                    $page_visit = $this->_get_page_visit();
-                    if ($page_visit) {
-                        // set pages visited where the first will be the http referrer
-                        $this->_session_data['pages_visited'][ $this->_time ] = $page_visit;
-                        // we'll only save the last 10 page visits.
-                        $session_data['pages_visited'] = array_slice($this->_session_data['pages_visited'], -10);
-                    }
-                    break;
-                default:
-                    // carry any other data over
-                    $session_data[ $key ] = $this->_session_data[ $key ];
-            }
-        }
-        $this->_session_data = $session_data;
-        // creating a new session does not require saving to the db just yet
-        if (! $new_session) {
-            // ready? let's save
-            if ($this->_save_session_to_db()) {
-                return true;
-            }
-            return false;
-        }
-        // meh, why not?
-        return true;
-    }
-
-
-    /**
-     * @create session data array
-     * @access public
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    private function _create_espresso_session()
-    {
-        do_action('AHEE_log', __CLASS__, __FUNCTION__, '');
-        // use the update function for now with $new_session arg set to TRUE
-        return $this->update(true) ? true : false;
-    }
-
-
-    /**
-     * _save_session_to_db
-     *
-     * @param bool $clear_session
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    private function _save_session_to_db($clear_session = false)
-    {
-        // don't save sessions for crawlers
-        // and unless we're deleting the session data, don't save anything if there isn't a cart
-        if ($this->request->isBot()
-            || (
-                ! $clear_session
-                && ! $this->cart() instanceof EE_Cart
-                && apply_filters('FHEE__EE_Session___save_session_to_db__abort_session_save', true)
-            )
-        ) {
-            return false;
-        }
-        $transaction = $this->transaction();
-        if ($transaction instanceof EE_Transaction) {
-            if (! $transaction->ID()) {
-                $transaction->save();
-            }
-            $this->_session_data['transaction'] = $transaction->ID();
-        }
-        // then serialize all of our session data
-        $session_data = serialize($this->_session_data);
-        // do we need to also encode it to avoid corrupted data when saved to the db?
-        $session_data = $this->_use_encryption
-            ? $this->encryption->base64_string_encode($session_data)
-            : $session_data;
-        // maybe save hash check
-        if (apply_filters('FHEE__EE_Session___perform_session_id_hash_check', WP_DEBUG)) {
-            $this->cache_storage->add(
-                EE_Session::hash_check_prefix . $this->_sid,
-                md5($session_data),
-                $this->session_lifespan->inSeconds()
-            );
-        }
-        // we're using the Transient API for storing session data,
-        return $this->cache_storage->add(
-            EE_Session::session_id_prefix . $this->_sid,
-            $session_data,
-            $this->session_lifespan->inSeconds()
-        );
-    }
-
-
-    /**
-     * @get    the full page request the visitor is accessing
-     * @access public
-     * @return string
-     */
-    public function _get_page_visit()
-    {
-        $page_visit = home_url('/') . 'wp-admin/admin-ajax.php';
-        // check for request url
-        if (isset($_SERVER['REQUEST_URI'])) {
-            $http_host = '';
-            $page_id = '?';
-            $e_reg = '';
-            $request_uri = esc_url($_SERVER['REQUEST_URI']);
-            $ru_bits = explode('?', $request_uri);
-            $request_uri = $ru_bits[0];
-            // check for and grab host as well
-            if (isset($_SERVER['HTTP_HOST'])) {
-                $http_host = esc_url($_SERVER['HTTP_HOST']);
-            }
-            // check for page_id in SERVER REQUEST
-            if (isset($_REQUEST['page_id'])) {
-                // rebuild $e_reg without any of the extra parameters
-                $page_id = '?page_id=' . esc_attr($_REQUEST['page_id']) . '&amp;';
-            }
-            // check for $e_reg in SERVER REQUEST
-            if (isset($_REQUEST['ee'])) {
-                // rebuild $e_reg without any of the extra parameters
-                $e_reg = 'ee=' . esc_attr($_REQUEST['ee']);
-            }
-            $page_visit = rtrim($http_host . $request_uri . $page_id . $e_reg, '?');
-        }
-        return $page_visit !== home_url('/wp-admin/admin-ajax.php') ? $page_visit : '';
-    }
-
-
-    /**
-     * @the    current wp user id
-     * @access public
-     * @return int
-     */
-    public function _wp_user_id()
-    {
-        // if I need to explain the following lines of code, then you shouldn't be looking at this!
-        $this->_wp_user_id = get_current_user_id();
-        return $this->_wp_user_id;
-    }
-
-
-    /**
-     * Clear EE_Session data
-     *
-     * @access public
-     * @param string $class
-     * @param string $function
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    public function clear_session($class = '', $function = '')
-    {
+	const session_id_prefix = 'ee_ssn_';
+
+	const hash_check_prefix = 'ee_shc_';
+
+	const OPTION_NAME_SETTINGS = 'ee_session_settings';
+
+	const STATUS_CLOSED = 0;
+
+	const STATUS_OPEN = 1;
+
+	/**
+	 * instance of the EE_Session object
+	 *
+	 * @var EE_Session
+	 */
+	private static $_instance;
+
+	/**
+	 * @var CacheStorageInterface $cache_storage
+	 */
+	protected $cache_storage;
+
+	/**
+	 * EE_Encryption object
+	 *
+	 * @var EE_Encryption
+	 */
+	protected $encryption;
+
+	/**
+	 * the session id
+	 *
+	 * @var string
+	 */
+	private $_sid;
+
+	/**
+	 * session id salt
+	 *
+	 * @var string
+	 */
+	private $_sid_salt;
+
+	/**
+	 * session data
+	 *
+	 * @var array
+	 */
+	private $_session_data = array();
+
+	/**
+	 * how long an EE session lasts
+	 * default session lifespan of 1 hour (for not so instant IPNs)
+	 *
+	 * @var SessionLifespan $session_lifespan
+	 */
+	private $session_lifespan;
+
+	/**
+	 * session expiration time as Unix timestamp in GMT
+	 *
+	 * @var int
+	 */
+	private $_expiration;
+
+	/**
+	 * whether or not session has expired at some point
+	 *
+	 * @var boolean
+	 */
+	private $_expired = false;
+
+	/**
+	 * current time as Unix timestamp in GMT
+	 *
+	 * @var int
+	 */
+	private $_time;
+
+	/**
+	 * whether to encrypt session data
+	 *
+	 * @var bool
+	 */
+	private $_use_encryption;
+
+	/**
+	 * well... according to the server...
+	 *
+	 * @var null
+	 */
+	private $_user_agent;
+
+	/**
+	 * do you really trust the server ?
+	 *
+	 * @var null
+	 */
+	private $_ip_address;
+
+	/**
+	 * current WP user_id
+	 *
+	 * @var null
+	 */
+	private $_wp_user_id;
+
+	/**
+	 * array for defining default session vars
+	 *
+	 * @var array
+	 */
+	private $_default_session_vars = array(
+		'id'            => null,
+		'user_id'       => null,
+		'ip_address'    => null,
+		'user_agent'    => null,
+		'init_access'   => null,
+		'last_access'   => null,
+		'expiration'    => null,
+		'pages_visited' => array(),
+	);
+
+	/**
+	 * timestamp for when last garbage collection cycle was performed
+	 *
+	 * @var int $_last_gc
+	 */
+	private $_last_gc;
+
+	/**
+	 * @var RequestInterface $request
+	 */
+	protected $request;
+
+	/**
+	 * whether session is active or not
+	 *
+	 * @var int $status
+	 */
+	private $status = EE_Session::STATUS_CLOSED;
+
+
+	/**
+	 * @singleton method used to instantiate class object
+	 * @param CacheStorageInterface $cache_storage
+	 * @param SessionLifespan|null  $lifespan
+	 * @param RequestInterface      $request
+	 * @param EE_Encryption         $encryption
+	 * @return EE_Session
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	public static function instance(
+		CacheStorageInterface $cache_storage = null,
+		SessionLifespan $lifespan = null,
+		RequestInterface $request = null,
+		EE_Encryption $encryption = null
+	) {
+		// check if class object is instantiated
+		// session loading is turned ON by default, but prior to the init hook, can be turned back OFF via:
+		// add_filter( 'FHEE_load_EE_Session', '__return_false' );
+		if (! self::$_instance instanceof EE_Session && apply_filters('FHEE_load_EE_Session', true)) {
+			self::$_instance = new self(
+				$cache_storage,
+				$lifespan,
+				$request,
+				$encryption
+			);
+		}
+		return self::$_instance;
+	}
+
+
+	/**
+	 * protected constructor to prevent direct creation
+	 *
+	 * @param CacheStorageInterface $cache_storage
+	 * @param SessionLifespan       $lifespan
+	 * @param RequestInterface      $request
+	 * @param EE_Encryption         $encryption
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	protected function __construct(
+		CacheStorageInterface $cache_storage,
+		SessionLifespan $lifespan,
+		RequestInterface $request,
+		EE_Encryption $encryption = null
+	) {
+		// session loading is turned ON by default,
+		// but prior to the 'AHEE__EE_System__core_loaded_and_ready' hook
+		// (which currently fires on the init hook at priority 9),
+		// can be turned back OFF via: add_filter( 'FHEE_load_EE_Session', '__return_false' );
+		if (! apply_filters('FHEE_load_EE_Session', true)) {
+			return;
+		}
+		$this->session_lifespan = $lifespan;
+		$this->request = $request;
+		if (! defined('ESPRESSO_SESSION')) {
+			define('ESPRESSO_SESSION', true);
+		}
+		// retrieve session options from db
+		$session_settings = (array) get_option(EE_Session::OPTION_NAME_SETTINGS, array());
+		if (! empty($session_settings)) {
+			// cycle though existing session options
+			foreach ($session_settings as $var_name => $session_setting) {
+				// set values for class properties
+				$var_name = '_' . $var_name;
+				$this->{$var_name} = $session_setting;
+			}
+		}
+		$this->cache_storage = $cache_storage;
+		// are we using encryption?
+		$this->_use_encryption = $encryption instanceof EE_Encryption
+								 && EE_Registry::instance()->CFG->admin->encode_session_data();
+		// encrypt data via: $this->encryption->encrypt();
+		$this->encryption = $encryption;
+		// filter hook allows outside functions/classes/plugins to change default empty cart
+		$extra_default_session_vars = apply_filters('FHEE__EE_Session__construct__extra_default_session_vars', array());
+		array_merge($this->_default_session_vars, $extra_default_session_vars);
+		// apply default session vars
+		$this->_set_defaults();
+		add_action('AHEE__EE_System__initialize', array($this, 'open_session'));
+		// check request for 'clear_session' param
+		add_action('AHEE__EE_Request_Handler__construct__complete', array($this, 'wp_loaded'));
+		// once everything is all said and done,
+		add_action('shutdown', array($this, 'update'), 100);
+		add_action('shutdown', array($this, 'garbageCollection'), 1000);
+		$this->configure_garbage_collection_filters();
+	}
+
+
+	/**
+	 * @return bool
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	public static function isLoadedAndActive()
+	{
+		return did_action('AHEE__EE_System__core_loaded_and_ready')
+			   && EE_Session::instance() instanceof EE_Session
+			   && EE_Session::instance()->isActive();
+	}
+
+
+	/**
+	 * @return bool
+	 */
+	public function isActive()
+	{
+		return $this->status === EE_Session::STATUS_OPEN;
+	}
+
+
+	/**
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidSessionDataException
+	 */
+	public function open_session()
+	{
+		// check for existing session and retrieve it from db
+		if (! $this->_espresso_session()) {
+			// or just start a new one
+			$this->_create_espresso_session();
+		}
+	}
+
+
+	/**
+	 * @return bool
+	 */
+	public function expired()
+	{
+		return $this->_expired;
+	}
+
+
+	/**
+	 * @return void
+	 */
+	public function reset_expired()
+	{
+		$this->_expired = false;
+	}
+
+
+	/**
+	 * @return int
+	 */
+	public function expiration()
+	{
+		return $this->_expiration;
+	}
+
+
+	/**
+	 * @return int
+	 */
+	public function extension()
+	{
+		return apply_filters('FHEE__EE_Session__extend_expiration__seconds_added', 10 * MINUTE_IN_SECONDS);
+	}
+
+
+	/**
+	 * @param int $time number of seconds to add to session expiration
+	 */
+	public function extend_expiration($time = 0)
+	{
+		$time = $time ? $time : $this->extension();
+		$this->_expiration += absint($time);
+	}
+
+
+	/**
+	 * @return int
+	 */
+	public function lifespan()
+	{
+		return $this->session_lifespan->inSeconds();
+	}
+
+
+	/**
+	 * This just sets some defaults for the _session data property
+	 *
+	 * @access private
+	 * @return void
+	 */
+	private function _set_defaults()
+	{
+		// set some defaults
+		foreach ($this->_default_session_vars as $key => $default_var) {
+			if (is_array($default_var)) {
+				$this->_session_data[ $key ] = array();
+			} else {
+				$this->_session_data[ $key ] = '';
+			}
+		}
+	}
+
+
+	/**
+	 * @retrieve  session data
+	 * @access    public
+	 * @return    string
+	 */
+	public function id()
+	{
+		return $this->_sid;
+	}
+
+
+	/**
+	 * @param \EE_Cart $cart
+	 * @return bool
+	 */
+	public function set_cart(EE_Cart $cart)
+	{
+		$this->_session_data['cart'] = $cart;
+		return true;
+	}
+
+
+	/**
+	 * reset_cart
+	 */
+	public function reset_cart()
+	{
+		do_action('AHEE__EE_Session__reset_cart__before_reset', $this);
+		$this->_session_data['cart'] = null;
+	}
+
+
+	/**
+	 * @return \EE_Cart
+	 */
+	public function cart()
+	{
+		return isset($this->_session_data['cart']) && $this->_session_data['cart'] instanceof EE_Cart
+			? $this->_session_data['cart']
+			: null;
+	}
+
+
+	/**
+	 * @param \EE_Checkout $checkout
+	 * @return bool
+	 */
+	public function set_checkout(EE_Checkout $checkout)
+	{
+		$this->_session_data['checkout'] = $checkout;
+		return true;
+	}
+
+
+	/**
+	 * reset_checkout
+	 */
+	public function reset_checkout()
+	{
+		do_action('AHEE__EE_Session__reset_checkout__before_reset', $this);
+		$this->_session_data['checkout'] = null;
+	}
+
+
+	/**
+	 * @return \EE_Checkout
+	 */
+	public function checkout()
+	{
+		return isset($this->_session_data['checkout']) && $this->_session_data['checkout'] instanceof EE_Checkout
+			? $this->_session_data['checkout']
+			: null;
+	}
+
+
+	/**
+	 * @param \EE_Transaction $transaction
+	 * @return bool
+	 * @throws EE_Error
+	 */
+	public function set_transaction(EE_Transaction $transaction)
+	{
+		// first remove the session from the transaction before we save the transaction in the session
+		$transaction->set_txn_session_data(null);
+		$this->_session_data['transaction'] = $transaction;
+		return true;
+	}
+
+
+	/**
+	 * reset_transaction
+	 */
+	public function reset_transaction()
+	{
+		do_action('AHEE__EE_Session__reset_transaction__before_reset', $this);
+		$this->_session_data['transaction'] = null;
+	}
+
+
+	/**
+	 * @return \EE_Transaction
+	 */
+	public function transaction()
+	{
+		return isset($this->_session_data['transaction'])
+			   && $this->_session_data['transaction'] instanceof EE_Transaction
+			? $this->_session_data['transaction']
+			: null;
+	}
+
+
+	/**
+	 * retrieve session data
+	 *
+	 * @param null $key
+	 * @param bool $reset_cache
+	 * @return array
+	 */
+	public function get_session_data($key = null, $reset_cache = false)
+	{
+		if ($reset_cache) {
+			$this->reset_cart();
+			$this->reset_checkout();
+			$this->reset_transaction();
+		}
+		if (! empty($key)) {
+			return isset($this->_session_data[ $key ]) ? $this->_session_data[ $key ] : null;
+		}
+		return $this->_session_data;
+	}
+
+
+	/**
+	 * Returns TRUE on success, FALSE on fail
+	 *
+	 * @param array $data
+	 * @return bool
+	 */
+	public function set_session_data($data)
+	{
+		// nothing ??? bad data ??? go home!
+		if (empty($data) || ! is_array($data)) {
+			EE_Error::add_error(
+				esc_html__(
+					'No session data or invalid session data was provided.',
+					'event_espresso'
+				),
+				__FILE__,
+				__FUNCTION__,
+				__LINE__
+			);
+			return false;
+		}
+		foreach ($data as $key => $value) {
+			if (isset($this->_default_session_vars[ $key ])) {
+				EE_Error::add_error(
+					sprintf(
+						esc_html__(
+							'Sorry! %s is a default session datum and can not be reset.',
+							'event_espresso'
+						),
+						$key
+					),
+					__FILE__,
+					__FUNCTION__,
+					__LINE__
+				);
+				return false;
+			}
+			$this->_session_data[ $key ] = $value;
+		}
+		return true;
+	}
+
+
+	/**
+	 * @initiate session
+	 * @access   private
+	 * @return TRUE on success, FALSE on fail
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidSessionDataException
+	 */
+	private function _espresso_session()
+	{
+		do_action('AHEE_log', __FILE__, __FUNCTION__, '');
+		// check that session has started
+		if (session_id() === '') {
+			// starts a new session if one doesn't already exist, or re-initiates an existing one
+			session_start();
+		}
+		$this->status = EE_Session::STATUS_OPEN;
+		// get our modified session ID
+		$this->_sid = $this->_generate_session_id();
+		// and the visitors IP
+		$this->_ip_address = $this->request->ipAddress();
+		// set the "user agent"
+		$this->_user_agent = $this->request->userAgent();
+		// now let's retrieve what's in the db
+		$session_data = $this->_retrieve_session_data();
+		if (! empty($session_data)) {
+			// get the current time in UTC
+			$this->_time = $this->_time !== null ? $this->_time : time();
+			// and reset the session expiration
+			$this->_expiration = isset($session_data['expiration'])
+				? $session_data['expiration']
+				: $this->_time + $this->session_lifespan->inSeconds();
+		} else {
+			// set initial site access time and the session expiration
+			$this->_set_init_access_and_expiration();
+			// set referer
+			$this->_session_data['pages_visited'][ $this->_session_data['init_access'] ] = isset($_SERVER['HTTP_REFERER'])
+				? esc_attr($_SERVER['HTTP_REFERER'])
+				: '';
+			// no previous session = go back and create one (on top of the data above)
+			return false;
+		}
+		// now the user agent
+		if ($session_data['user_agent'] !== $this->_user_agent) {
+			return false;
+		}
+		// wait a minute... how old are you?
+		if ($this->_time > $this->_expiration) {
+			// yer too old fer me!
+			$this->_expired = true;
+			// wipe out everything that isn't a default session datum
+			$this->clear_session(__CLASS__, __FUNCTION__);
+		}
+		// make event espresso session data available to plugin
+		$this->_session_data = array_merge($this->_session_data, $session_data);
+		return true;
+	}
+
+
+	/**
+	 * _get_session_data
+	 * Retrieves the session data, and attempts to correct any encoding issues that can occur due to improperly setup
+	 * databases
+	 *
+	 * @return array
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidSessionDataException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	protected function _retrieve_session_data()
+	{
+		$ssn_key = EE_Session::session_id_prefix . $this->_sid;
+		try {
+			// we're using WP's Transient API to store session data using the PHP session ID as the option name
+			$session_data = $this->cache_storage->get($ssn_key, false);
+			if (empty($session_data)) {
+				return array();
+			}
+			if (apply_filters('FHEE__EE_Session___perform_session_id_hash_check', WP_DEBUG)) {
+				$hash_check = $this->cache_storage->get(
+					EE_Session::hash_check_prefix . $this->_sid,
+					false
+				);
+				if ($hash_check && $hash_check !== md5($session_data)) {
+					EE_Error::add_error(
+						sprintf(
+							__(
+								'The stored data for session %1$s failed to pass a hash check and therefore appears to be invalid.',
+								'event_espresso'
+							),
+							EE_Session::session_id_prefix . $this->_sid
+						),
+						__FILE__,
+						__FUNCTION__,
+						__LINE__
+					);
+				}
+			}
+		} catch (Exception $e) {
+			// let's just eat that error for now and attempt to correct any corrupted data
+			global $wpdb;
+			$row = $wpdb->get_row(
+				$wpdb->prepare(
+					"SELECT option_value FROM {$wpdb->options} WHERE option_name = %s LIMIT 1",
+					'_transient_' . $ssn_key
+				)
+			);
+			$session_data = is_object($row) ? $row->option_value : null;
+			if ($session_data) {
+				$session_data = preg_replace_callback(
+					'!s:(d+):"(.*?)";!',
+					function ($match) {
+						return $match[1] === strlen($match[2])
+							? $match[0]
+							: 's:' . strlen($match[2]) . ':"' . $match[2] . '";';
+					},
+					$session_data
+				);
+			}
+			$session_data = maybe_unserialize($session_data);
+		}
+		// in case the data is encoded... try to decode it
+		$session_data = $this->encryption instanceof EE_Encryption
+			? $this->encryption->base64_string_decode($session_data)
+			: $session_data;
+		if (! is_array($session_data)) {
+			try {
+				$session_data = maybe_unserialize($session_data);
+			} catch (Exception $e) {
+				$msg = esc_html__(
+					'An error occurred while attempting to unserialize the session data.',
+					'event_espresso'
+				);
+				$msg .= WP_DEBUG
+					? '<br><pre>'
+					  . print_r($session_data, true)
+					  . '</pre><br>'
+					  . $this->find_serialize_error($session_data)
+					: '';
+				$this->cache_storage->delete(EE_Session::session_id_prefix . $this->_sid);
+				throw new InvalidSessionDataException($msg, 0, $e);
+			}
+		}
+		// just a check to make sure the session array is indeed an array
+		if (! is_array($session_data)) {
+			// no?!?! then something is wrong
+			$msg = esc_html__(
+				'The session data is missing, invalid, or corrupted.',
+				'event_espresso'
+			);
+			$msg .= WP_DEBUG
+				? '<br><pre>' . print_r($session_data, true) . '</pre><br>' . $this->find_serialize_error($session_data)
+				: '';
+			$this->cache_storage->delete(EE_Session::session_id_prefix . $this->_sid);
+			throw new InvalidSessionDataException($msg);
+		}
+		if (isset($session_data['transaction']) && absint($session_data['transaction']) !== 0) {
+			$session_data['transaction'] = EEM_Transaction::instance()->get_one_by_ID(
+				$session_data['transaction']
+			);
+		}
+		return $session_data;
+	}
+
+
+	/**
+	 * _generate_session_id
+	 * Retrieves the PHP session id either directly from the PHP session,
+	 * or from the $_REQUEST array if it was passed in from an AJAX request.
+	 * The session id is then salted and hashed (mmm sounds tasty)
+	 * so that it can be safely used as a $_REQUEST param
+	 *
+	 * @return string
+	 */
+	protected function _generate_session_id()
+	{
+		// check if the SID was passed explicitly, otherwise get from session, then add salt and hash it to reduce length
+		if (isset($_REQUEST['EESID'])) {
+			$session_id = sanitize_text_field($_REQUEST['EESID']);
+		} else {
+			$session_id = md5(session_id() . get_current_blog_id() . $this->_get_sid_salt());
+		}
+		return apply_filters('FHEE__EE_Session___generate_session_id__session_id', $session_id);
+	}
+
+
+	/**
+	 * _get_sid_salt
+	 *
+	 * @return string
+	 */
+	protected function _get_sid_salt()
+	{
+		// was session id salt already saved to db ?
+		if (empty($this->_sid_salt)) {
+			// no?  then maybe use WP defined constant
+			if (defined('AUTH_SALT')) {
+				$this->_sid_salt = AUTH_SALT;
+			}
+			// if salt doesn't exist or is too short
+			if (strlen($this->_sid_salt) < 32) {
+				// create a new one
+				$this->_sid_salt = wp_generate_password(64);
+			}
+			// and save it as a permanent session setting
+			$this->updateSessionSettings(array('sid_salt' => $this->_sid_salt));
+		}
+		return $this->_sid_salt;
+	}
+
+
+	/**
+	 * _set_init_access_and_expiration
+	 *
+	 * @return void
+	 */
+	protected function _set_init_access_and_expiration()
+	{
+		$this->_time = time();
+		$this->_expiration = $this->_time + $this->session_lifespan->inSeconds();
+		// set initial site access time
+		$this->_session_data['init_access'] = $this->_time;
+		// and the session expiration
+		$this->_session_data['expiration'] = $this->_expiration;
+	}
+
+
+	/**
+	 * @update session data  prior to saving to the db
+	 * @access public
+	 * @param bool $new_session
+	 * @return TRUE on success, FALSE on fail
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	public function update($new_session = false)
+	{
+		$this->_session_data = $this->_session_data !== null
+							   && is_array($this->_session_data)
+							   && isset($this->_session_data['id'])
+			? $this->_session_data
+			: array();
+		if (empty($this->_session_data)) {
+			$this->_set_defaults();
+		}
+		$session_data = array();
+		foreach ($this->_session_data as $key => $value) {
+			switch ($key) {
+				case 'id':
+					// session ID
+					$session_data['id'] = $this->_sid;
+					break;
+				case 'ip_address':
+					// visitor ip address
+					$session_data['ip_address'] = $this->request->ipAddress();
+					break;
+				case 'user_agent':
+					// visitor user_agent
+					$session_data['user_agent'] = $this->_user_agent;
+					break;
+				case 'init_access':
+					$session_data['init_access'] = absint($value);
+					break;
+				case 'last_access':
+					// current access time
+					$session_data['last_access'] = $this->_time;
+					break;
+				case 'expiration':
+					// when the session expires
+					$session_data['expiration'] = ! empty($this->_expiration)
+						? $this->_expiration
+						: $session_data['init_access'] + $this->session_lifespan->inSeconds();
+					break;
+				case 'user_id':
+					// current user if logged in
+					$session_data['user_id'] = $this->_wp_user_id();
+					break;
+				case 'pages_visited':
+					$page_visit = $this->_get_page_visit();
+					if ($page_visit) {
+						// set pages visited where the first will be the http referrer
+						$this->_session_data['pages_visited'][ $this->_time ] = $page_visit;
+						// we'll only save the last 10 page visits.
+						$session_data['pages_visited'] = array_slice($this->_session_data['pages_visited'], -10);
+					}
+					break;
+				default:
+					// carry any other data over
+					$session_data[ $key ] = $this->_session_data[ $key ];
+			}
+		}
+		$this->_session_data = $session_data;
+		// creating a new session does not require saving to the db just yet
+		if (! $new_session) {
+			// ready? let's save
+			if ($this->_save_session_to_db()) {
+				return true;
+			}
+			return false;
+		}
+		// meh, why not?
+		return true;
+	}
+
+
+	/**
+	 * @create session data array
+	 * @access public
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	private function _create_espresso_session()
+	{
+		do_action('AHEE_log', __CLASS__, __FUNCTION__, '');
+		// use the update function for now with $new_session arg set to TRUE
+		return $this->update(true) ? true : false;
+	}
+
+
+	/**
+	 * _save_session_to_db
+	 *
+	 * @param bool $clear_session
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	private function _save_session_to_db($clear_session = false)
+	{
+		// don't save sessions for crawlers
+		// and unless we're deleting the session data, don't save anything if there isn't a cart
+		if ($this->request->isBot()
+			|| (
+				! $clear_session
+				&& ! $this->cart() instanceof EE_Cart
+				&& apply_filters('FHEE__EE_Session___save_session_to_db__abort_session_save', true)
+			)
+		) {
+			return false;
+		}
+		$transaction = $this->transaction();
+		if ($transaction instanceof EE_Transaction) {
+			if (! $transaction->ID()) {
+				$transaction->save();
+			}
+			$this->_session_data['transaction'] = $transaction->ID();
+		}
+		// then serialize all of our session data
+		$session_data = serialize($this->_session_data);
+		// do we need to also encode it to avoid corrupted data when saved to the db?
+		$session_data = $this->_use_encryption
+			? $this->encryption->base64_string_encode($session_data)
+			: $session_data;
+		// maybe save hash check
+		if (apply_filters('FHEE__EE_Session___perform_session_id_hash_check', WP_DEBUG)) {
+			$this->cache_storage->add(
+				EE_Session::hash_check_prefix . $this->_sid,
+				md5($session_data),
+				$this->session_lifespan->inSeconds()
+			);
+		}
+		// we're using the Transient API for storing session data,
+		return $this->cache_storage->add(
+			EE_Session::session_id_prefix . $this->_sid,
+			$session_data,
+			$this->session_lifespan->inSeconds()
+		);
+	}
+
+
+	/**
+	 * @get    the full page request the visitor is accessing
+	 * @access public
+	 * @return string
+	 */
+	public function _get_page_visit()
+	{
+		$page_visit = home_url('/') . 'wp-admin/admin-ajax.php';
+		// check for request url
+		if (isset($_SERVER['REQUEST_URI'])) {
+			$http_host = '';
+			$page_id = '?';
+			$e_reg = '';
+			$request_uri = esc_url($_SERVER['REQUEST_URI']);
+			$ru_bits = explode('?', $request_uri);
+			$request_uri = $ru_bits[0];
+			// check for and grab host as well
+			if (isset($_SERVER['HTTP_HOST'])) {
+				$http_host = esc_url($_SERVER['HTTP_HOST']);
+			}
+			// check for page_id in SERVER REQUEST
+			if (isset($_REQUEST['page_id'])) {
+				// rebuild $e_reg without any of the extra parameters
+				$page_id = '?page_id=' . esc_attr($_REQUEST['page_id']) . '&amp;';
+			}
+			// check for $e_reg in SERVER REQUEST
+			if (isset($_REQUEST['ee'])) {
+				// rebuild $e_reg without any of the extra parameters
+				$e_reg = 'ee=' . esc_attr($_REQUEST['ee']);
+			}
+			$page_visit = rtrim($http_host . $request_uri . $page_id . $e_reg, '?');
+		}
+		return $page_visit !== home_url('/wp-admin/admin-ajax.php') ? $page_visit : '';
+	}
+
+
+	/**
+	 * @the    current wp user id
+	 * @access public
+	 * @return int
+	 */
+	public function _wp_user_id()
+	{
+		// if I need to explain the following lines of code, then you shouldn't be looking at this!
+		$this->_wp_user_id = get_current_user_id();
+		return $this->_wp_user_id;
+	}
+
+
+	/**
+	 * Clear EE_Session data
+	 *
+	 * @access public
+	 * @param string $class
+	 * @param string $function
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	public function clear_session($class = '', $function = '')
+	{
 //         echo '
 // <h3 style="color:#999;line-height:.9em;">
 // <span style="color:#2EA2CC">' . __CLASS__ . '</span>::<span style="color:#E76700">' . __FUNCTION__ . '( ' . $class . '::' . $function . '() )</span><br/>
 // <span style="font-size:9px;font-weight:normal;">' . __FILE__ . '</span>    <b style="font-size:10px;">  ' . __LINE__ . ' </b>
 // </h3>';
-        do_action('AHEE_log', __FILE__, __FUNCTION__, 'session cleared by : ' . $class . '::' . $function . '()');
-        $this->reset_cart();
-        $this->reset_checkout();
-        $this->reset_transaction();
-        // wipe out everything that isn't a default session datum
-        $this->reset_data(array_keys($this->_session_data));
-        // reset initial site access time and the session expiration
-        $this->_set_init_access_and_expiration();
-        $this->_save_session_to_db(true);
-    }
-
-
-    /**
-     * resets all non-default session vars. Returns TRUE on success, FALSE on fail
-     *
-     * @param array|mixed $data_to_reset
-     * @param bool        $show_all_notices
-     * @return bool
-     */
-    public function reset_data($data_to_reset = array(), $show_all_notices = false)
-    {
-        // if $data_to_reset is not in an array, then put it in one
-        if (! is_array($data_to_reset)) {
-            $data_to_reset = array($data_to_reset);
-        }
-        // nothing ??? go home!
-        if (empty($data_to_reset)) {
-            EE_Error::add_error(
-                __(
-                    'No session data could be reset, because no session var name was provided.',
-                    'event_espresso'
-                ),
-                __FILE__,
-                __FUNCTION__,
-                __LINE__
-            );
-            return false;
-        }
-        $return_value = true;
-        // since $data_to_reset is an array, cycle through the values
-        foreach ($data_to_reset as $reset) {
-            // first check to make sure it is a valid session var
-            if (isset($this->_session_data[ $reset ])) {
-                // then check to make sure it is not a default var
-                if (! array_key_exists($reset, $this->_default_session_vars)) {
-                    // remove session var
-                    unset($this->_session_data[ $reset ]);
-                    if ($show_all_notices) {
-                        EE_Error::add_success(
-                            sprintf(
-                                __('The session variable %s was removed.', 'event_espresso'),
-                                $reset
-                            ),
-                            __FILE__,
-                            __FUNCTION__,
-                            __LINE__
-                        );
-                    }
-                } else {
-                    // yeeeeeeeeerrrrrrrrrrr OUT !!!!
-                    if ($show_all_notices) {
-                        EE_Error::add_error(
-                            sprintf(
-                                __(
-                                    'Sorry! %s is a default session datum and can not be reset.',
-                                    'event_espresso'
-                                ),
-                                $reset
-                            ),
-                            __FILE__,
-                            __FUNCTION__,
-                            __LINE__
-                        );
-                    }
-                    $return_value = false;
-                }
-            } elseif ($show_all_notices) {
-                // oops! that session var does not exist!
-                EE_Error::add_error(
-                    sprintf(
-                        __(
-                            'The session item provided, %s, is invalid or does not exist.',
-                            'event_espresso'
-                        ),
-                        $reset
-                    ),
-                    __FILE__,
-                    __FUNCTION__,
-                    __LINE__
-                );
-                $return_value = false;
-            }
-        } // end of foreach
-        return $return_value;
-    }
-
-
-    /**
-     *   wp_loaded
-     *
-     * @access public
-     * @throws EE_Error
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws InvalidArgumentException
-     */
-    public function wp_loaded()
-    {
-        if ($this->request->requestParamIsSet('clear_session')) {
-            $this->clear_session(__CLASS__, __FUNCTION__);
-        }
-    }
-
-
-    /**
-     * Used to reset the entire object (for tests).
-     *
-     * @since 4.3.0
-     * @throws EE_Error
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws InvalidArgumentException
-     */
-    public function reset_instance()
-    {
-        $this->clear_session();
-        self::$_instance = null;
-    }
-
-
-    public function configure_garbage_collection_filters()
-    {
-        // run old filter we had for controlling session cleanup
-        $expired_session_transient_delete_query_limit = absint(
-            apply_filters(
-                'FHEE__EE_Session__garbage_collection___expired_session_transient_delete_query_limit',
-                50
-            )
-        );
-        // is there a value? or one that is different than the default 50 records?
-        if ($expired_session_transient_delete_query_limit === 0) {
-            // hook into TransientCacheStorage in case Session cleanup was turned off
-            add_filter('FHEE__TransientCacheStorage__transient_cleanup_schedule', '__return_zero');
-        } elseif ($expired_session_transient_delete_query_limit !== 50) {
-            // or use that for the new transient cleanup query limit
-            add_filter(
-                'FHEE__TransientCacheStorage__clearExpiredTransients__limit',
-                function () use ($expired_session_transient_delete_query_limit) {
-                    return $expired_session_transient_delete_query_limit;
-                }
-            );
-        }
-    }
-
-
-    /**
-     * @see http://stackoverflow.com/questions/10152904/unserialize-function-unserialize-error-at-offset/21389439#10152996
-     * @param $data1
-     * @return string
-     */
-    private function find_serialize_error($data1)
-    {
-        $error = '<pre>';
-        $data2 = preg_replace_callback(
-            '!s:(\d+):"(.*?)";!',
-            function ($match) {
-                return ($match[1] === strlen($match[2]))
-                    ? $match[0]
-                    : 's:'
-                      . strlen($match[2])
-                      . ':"'
-                      . $match[2]
-                      . '";';
-            },
-            $data1
-        );
-        $max = (strlen($data1) > strlen($data2)) ? strlen($data1) : strlen($data2);
-        $error .= $data1 . PHP_EOL;
-        $error .= $data2 . PHP_EOL;
-        for ($i = 0; $i < $max; $i++) {
-            if (@$data1[ $i ] !== @$data2[ $i ]) {
-                $error .= 'Difference ' . @$data1[ $i ] . ' != ' . @$data2[ $i ] . PHP_EOL;
-                $error .= "\t-> ORD number " . ord(@$data1[ $i ]) . ' != ' . ord(@$data2[ $i ]) . PHP_EOL;
-                $error .= "\t-> Line Number = $i" . PHP_EOL;
-                $start = ($i - 20);
-                $start = ($start < 0) ? 0 : $start;
-                $length = 40;
-                $point = $max - $i;
-                if ($point < 20) {
-                    $rlength = 1;
-                    $rpoint = -$point;
-                } else {
-                    $rpoint = $length - 20;
-                    $rlength = 1;
-                }
-                $error .= "\t-> Section Data1  = ";
-                $error .= substr_replace(
-                    substr($data1, $start, $length),
-                    "<b style=\"color:green\">{$data1[ $i ]}</b>",
-                    $rpoint,
-                    $rlength
-                );
-                $error .= PHP_EOL;
-                $error .= "\t-> Section Data2  = ";
-                $error .= substr_replace(
-                    substr($data2, $start, $length),
-                    "<b style=\"color:red\">{$data2[ $i ]}</b>",
-                    $rpoint,
-                    $rlength
-                );
-                $error .= PHP_EOL;
-            }
-        }
-        $error .= '</pre>';
-        return $error;
-    }
-
-
-    /**
-     * Saves an  array of settings used for configuring aspects of session behaviour
-     *
-     * @param array $updated_settings
-     */
-    private function updateSessionSettings(array $updated_settings = array())
-    {
-        // add existing settings, but only if not included in incoming $updated_settings array
-        $updated_settings += get_option(EE_Session::OPTION_NAME_SETTINGS, array());
-        update_option(EE_Session::OPTION_NAME_SETTINGS, $updated_settings);
-    }
-
-
-    /**
-     * garbage_collection
-     */
-    public function garbageCollection()
-    {
-        // only perform during regular requests if last garbage collection was over an hour ago
-        if (! (defined('DOING_AJAX') && DOING_AJAX) && (time() - HOUR_IN_SECONDS) >= $this->_last_gc) {
-            $this->_last_gc = time();
-            $this->updateSessionSettings(array('last_gc' => $this->_last_gc));
-            /** @type WPDB $wpdb */
-            global $wpdb;
-            // filter the query limit. Set to 0 to turn off garbage collection
-            $expired_session_transient_delete_query_limit = absint(
-                apply_filters(
-                    'FHEE__EE_Session__garbage_collection___expired_session_transient_delete_query_limit',
-                    50
-                )
-            );
-            // non-zero LIMIT means take out the trash
-            if ($expired_session_transient_delete_query_limit) {
-                $session_key = str_replace('_', '\_', EE_Session::session_id_prefix);
-                $hash_check_key = str_replace('_', '\_', EE_Session::hash_check_prefix);
-                // since transient expiration timestamps are set in the future, we can compare against NOW
-                // but we only want to pick up any trash that's been around for more than a day
-                $expiration = time() - DAY_IN_SECONDS;
-                $SQL = "
+		do_action('AHEE_log', __FILE__, __FUNCTION__, 'session cleared by : ' . $class . '::' . $function . '()');
+		$this->reset_cart();
+		$this->reset_checkout();
+		$this->reset_transaction();
+		// wipe out everything that isn't a default session datum
+		$this->reset_data(array_keys($this->_session_data));
+		// reset initial site access time and the session expiration
+		$this->_set_init_access_and_expiration();
+		$this->_save_session_to_db(true);
+	}
+
+
+	/**
+	 * resets all non-default session vars. Returns TRUE on success, FALSE on fail
+	 *
+	 * @param array|mixed $data_to_reset
+	 * @param bool        $show_all_notices
+	 * @return bool
+	 */
+	public function reset_data($data_to_reset = array(), $show_all_notices = false)
+	{
+		// if $data_to_reset is not in an array, then put it in one
+		if (! is_array($data_to_reset)) {
+			$data_to_reset = array($data_to_reset);
+		}
+		// nothing ??? go home!
+		if (empty($data_to_reset)) {
+			EE_Error::add_error(
+				__(
+					'No session data could be reset, because no session var name was provided.',
+					'event_espresso'
+				),
+				__FILE__,
+				__FUNCTION__,
+				__LINE__
+			);
+			return false;
+		}
+		$return_value = true;
+		// since $data_to_reset is an array, cycle through the values
+		foreach ($data_to_reset as $reset) {
+			// first check to make sure it is a valid session var
+			if (isset($this->_session_data[ $reset ])) {
+				// then check to make sure it is not a default var
+				if (! array_key_exists($reset, $this->_default_session_vars)) {
+					// remove session var
+					unset($this->_session_data[ $reset ]);
+					if ($show_all_notices) {
+						EE_Error::add_success(
+							sprintf(
+								__('The session variable %s was removed.', 'event_espresso'),
+								$reset
+							),
+							__FILE__,
+							__FUNCTION__,
+							__LINE__
+						);
+					}
+				} else {
+					// yeeeeeeeeerrrrrrrrrrr OUT !!!!
+					if ($show_all_notices) {
+						EE_Error::add_error(
+							sprintf(
+								__(
+									'Sorry! %s is a default session datum and can not be reset.',
+									'event_espresso'
+								),
+								$reset
+							),
+							__FILE__,
+							__FUNCTION__,
+							__LINE__
+						);
+					}
+					$return_value = false;
+				}
+			} elseif ($show_all_notices) {
+				// oops! that session var does not exist!
+				EE_Error::add_error(
+					sprintf(
+						__(
+							'The session item provided, %s, is invalid or does not exist.',
+							'event_espresso'
+						),
+						$reset
+					),
+					__FILE__,
+					__FUNCTION__,
+					__LINE__
+				);
+				$return_value = false;
+			}
+		} // end of foreach
+		return $return_value;
+	}
+
+
+	/**
+	 *   wp_loaded
+	 *
+	 * @access public
+	 * @throws EE_Error
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidArgumentException
+	 */
+	public function wp_loaded()
+	{
+		if ($this->request->requestParamIsSet('clear_session')) {
+			$this->clear_session(__CLASS__, __FUNCTION__);
+		}
+	}
+
+
+	/**
+	 * Used to reset the entire object (for tests).
+	 *
+	 * @since 4.3.0
+	 * @throws EE_Error
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidArgumentException
+	 */
+	public function reset_instance()
+	{
+		$this->clear_session();
+		self::$_instance = null;
+	}
+
+
+	public function configure_garbage_collection_filters()
+	{
+		// run old filter we had for controlling session cleanup
+		$expired_session_transient_delete_query_limit = absint(
+			apply_filters(
+				'FHEE__EE_Session__garbage_collection___expired_session_transient_delete_query_limit',
+				50
+			)
+		);
+		// is there a value? or one that is different than the default 50 records?
+		if ($expired_session_transient_delete_query_limit === 0) {
+			// hook into TransientCacheStorage in case Session cleanup was turned off
+			add_filter('FHEE__TransientCacheStorage__transient_cleanup_schedule', '__return_zero');
+		} elseif ($expired_session_transient_delete_query_limit !== 50) {
+			// or use that for the new transient cleanup query limit
+			add_filter(
+				'FHEE__TransientCacheStorage__clearExpiredTransients__limit',
+				function () use ($expired_session_transient_delete_query_limit) {
+					return $expired_session_transient_delete_query_limit;
+				}
+			);
+		}
+	}
+
+
+	/**
+	 * @see http://stackoverflow.com/questions/10152904/unserialize-function-unserialize-error-at-offset/21389439#10152996
+	 * @param $data1
+	 * @return string
+	 */
+	private function find_serialize_error($data1)
+	{
+		$error = '<pre>';
+		$data2 = preg_replace_callback(
+			'!s:(\d+):"(.*?)";!',
+			function ($match) {
+				return ($match[1] === strlen($match[2]))
+					? $match[0]
+					: 's:'
+					  . strlen($match[2])
+					  . ':"'
+					  . $match[2]
+					  . '";';
+			},
+			$data1
+		);
+		$max = (strlen($data1) > strlen($data2)) ? strlen($data1) : strlen($data2);
+		$error .= $data1 . PHP_EOL;
+		$error .= $data2 . PHP_EOL;
+		for ($i = 0; $i < $max; $i++) {
+			if (@$data1[ $i ] !== @$data2[ $i ]) {
+				$error .= 'Difference ' . @$data1[ $i ] . ' != ' . @$data2[ $i ] . PHP_EOL;
+				$error .= "\t-> ORD number " . ord(@$data1[ $i ]) . ' != ' . ord(@$data2[ $i ]) . PHP_EOL;
+				$error .= "\t-> Line Number = $i" . PHP_EOL;
+				$start = ($i - 20);
+				$start = ($start < 0) ? 0 : $start;
+				$length = 40;
+				$point = $max - $i;
+				if ($point < 20) {
+					$rlength = 1;
+					$rpoint = -$point;
+				} else {
+					$rpoint = $length - 20;
+					$rlength = 1;
+				}
+				$error .= "\t-> Section Data1  = ";
+				$error .= substr_replace(
+					substr($data1, $start, $length),
+					"<b style=\"color:green\">{$data1[ $i ]}</b>",
+					$rpoint,
+					$rlength
+				);
+				$error .= PHP_EOL;
+				$error .= "\t-> Section Data2  = ";
+				$error .= substr_replace(
+					substr($data2, $start, $length),
+					"<b style=\"color:red\">{$data2[ $i ]}</b>",
+					$rpoint,
+					$rlength
+				);
+				$error .= PHP_EOL;
+			}
+		}
+		$error .= '</pre>';
+		return $error;
+	}
+
+
+	/**
+	 * Saves an  array of settings used for configuring aspects of session behaviour
+	 *
+	 * @param array $updated_settings
+	 */
+	private function updateSessionSettings(array $updated_settings = array())
+	{
+		// add existing settings, but only if not included in incoming $updated_settings array
+		$updated_settings += get_option(EE_Session::OPTION_NAME_SETTINGS, array());
+		update_option(EE_Session::OPTION_NAME_SETTINGS, $updated_settings);
+	}
+
+
+	/**
+	 * garbage_collection
+	 */
+	public function garbageCollection()
+	{
+		// only perform during regular requests if last garbage collection was over an hour ago
+		if (! (defined('DOING_AJAX') && DOING_AJAX) && (time() - HOUR_IN_SECONDS) >= $this->_last_gc) {
+			$this->_last_gc = time();
+			$this->updateSessionSettings(array('last_gc' => $this->_last_gc));
+			/** @type WPDB $wpdb */
+			global $wpdb;
+			// filter the query limit. Set to 0 to turn off garbage collection
+			$expired_session_transient_delete_query_limit = absint(
+				apply_filters(
+					'FHEE__EE_Session__garbage_collection___expired_session_transient_delete_query_limit',
+					50
+				)
+			);
+			// non-zero LIMIT means take out the trash
+			if ($expired_session_transient_delete_query_limit) {
+				$session_key = str_replace('_', '\_', EE_Session::session_id_prefix);
+				$hash_check_key = str_replace('_', '\_', EE_Session::hash_check_prefix);
+				// since transient expiration timestamps are set in the future, we can compare against NOW
+				// but we only want to pick up any trash that's been around for more than a day
+				$expiration = time() - DAY_IN_SECONDS;
+				$SQL = "
                     SELECT option_name
                     FROM {$wpdb->options}
                     WHERE
@@ -1262,17 +1262,17 @@ 
                     AND option_value < {$expiration}
                     LIMIT {$expired_session_transient_delete_query_limit}
                 ";
-                // produces something like:
-                // SELECT option_name FROM wp_options
-                // WHERE ( option_name LIKE '\_transient\_timeout\_ee\_ssn\_%'
-                // OR option_name LIKE '\_transient\_timeout\_ee\_shc\_%' )
-                // AND option_value < 1508368198 LIMIT 50
-                $expired_sessions = $wpdb->get_col($SQL);
-                // valid results?
-                if (! $expired_sessions instanceof WP_Error && ! empty($expired_sessions)) {
-                    $this->cache_storage->deleteMany($expired_sessions, true);
-                }
-            }
-        }
-    }
+				// produces something like:
+				// SELECT option_name FROM wp_options
+				// WHERE ( option_name LIKE '\_transient\_timeout\_ee\_ssn\_%'
+				// OR option_name LIKE '\_transient\_timeout\_ee\_shc\_%' )
+				// AND option_value < 1508368198 LIMIT 50
+				$expired_sessions = $wpdb->get_col($SQL);
+				// valid results?
+				if (! $expired_sessions instanceof WP_Error && ! empty($expired_sessions)) {
+					$this->cache_storage->deleteMany($expired_sessions, true);
+				}
+			}
+		}
+	}
 }

Spacing +53 added lines, -53 removed lines

@@ -186,7 +186,7 @@ 
         // check if class object is instantiated
         // session loading is turned ON by default, but prior to the init hook, can be turned back OFF via:
         // add_filter( 'FHEE_load_EE_Session', '__return_false' );
-        if (! self::$_instance instanceof EE_Session && apply_filters('FHEE_load_EE_Session', true)) {
+        if ( ! self::$_instance instanceof EE_Session && apply_filters('FHEE_load_EE_Session', true)) {
             self::$_instance = new self(
                 $cache_storage,
                 $lifespan,
@@ -219,21 +219,21 @@ 
         // but prior to the 'AHEE__EE_System__core_loaded_and_ready' hook
         // (which currently fires on the init hook at priority 9),
         // can be turned back OFF via: add_filter( 'FHEE_load_EE_Session', '__return_false' );
-        if (! apply_filters('FHEE_load_EE_Session', true)) {
+        if ( ! apply_filters('FHEE_load_EE_Session', true)) {
             return;
         }
         $this->session_lifespan = $lifespan;
         $this->request = $request;
-        if (! defined('ESPRESSO_SESSION')) {
+        if ( ! defined('ESPRESSO_SESSION')) {
             define('ESPRESSO_SESSION', true);
         }
         // retrieve session options from db
         $session_settings = (array) get_option(EE_Session::OPTION_NAME_SETTINGS, array());
-        if (! empty($session_settings)) {
+        if ( ! empty($session_settings)) {
             // cycle though existing session options
             foreach ($session_settings as $var_name => $session_setting) {
                 // set values for class properties
-                $var_name = '_' . $var_name;
+                $var_name = '_'.$var_name;
                 $this->{$var_name} = $session_setting;
             }
         }
@@ -292,7 +292,7 @@ 
     public function open_session()
     {
         // check for existing session and retrieve it from db
-        if (! $this->_espresso_session()) {
+        if ( ! $this->_espresso_session()) {
             // or just start a new one
             $this->_create_espresso_session();
         }
@@ -365,9 +365,9 @@ 
         // set some defaults
         foreach ($this->_default_session_vars as $key => $default_var) {
             if (is_array($default_var)) {
-                $this->_session_data[ $key ] = array();
+                $this->_session_data[$key] = array();
             } else {
-                $this->_session_data[ $key ] = '';
+                $this->_session_data[$key] = '';
             }
         }
     }
@@ -498,8 +498,8 @@ 
             $this->reset_checkout();
             $this->reset_transaction();
         }
-        if (! empty($key)) {
-            return isset($this->_session_data[ $key ]) ? $this->_session_data[ $key ] : null;
+        if ( ! empty($key)) {
+            return isset($this->_session_data[$key]) ? $this->_session_data[$key] : null;
         }
         return $this->_session_data;
     }
@@ -527,7 +527,7 @@ 
             return false;
         }
         foreach ($data as $key => $value) {
-            if (isset($this->_default_session_vars[ $key ])) {
+            if (isset($this->_default_session_vars[$key])) {
                 EE_Error::add_error(
                     sprintf(
                         esc_html__(
@@ -542,7 +542,7 @@ 
                 );
                 return false;
             }
-            $this->_session_data[ $key ] = $value;
+            $this->_session_data[$key] = $value;
         }
         return true;
     }
@@ -575,7 +575,7 @@ 
         $this->_user_agent = $this->request->userAgent();
         // now let's retrieve what's in the db
         $session_data = $this->_retrieve_session_data();
-        if (! empty($session_data)) {
+        if ( ! empty($session_data)) {
             // get the current time in UTC
             $this->_time = $this->_time !== null ? $this->_time : time();
             // and reset the session expiration
@@ -586,7 +586,7 @@ 
             // set initial site access time and the session expiration
             $this->_set_init_access_and_expiration();
             // set referer
-            $this->_session_data['pages_visited'][ $this->_session_data['init_access'] ] = isset($_SERVER['HTTP_REFERER'])
+            $this->_session_data['pages_visited'][$this->_session_data['init_access']] = isset($_SERVER['HTTP_REFERER'])
                 ? esc_attr($_SERVER['HTTP_REFERER'])
                 : '';
             // no previous session = go back and create one (on top of the data above)
@@ -623,7 +623,7 @@ 
      */
     protected function _retrieve_session_data()
     {
-        $ssn_key = EE_Session::session_id_prefix . $this->_sid;
+        $ssn_key = EE_Session::session_id_prefix.$this->_sid;
         try {
             // we're using WP's Transient API to store session data using the PHP session ID as the option name
             $session_data = $this->cache_storage->get($ssn_key, false);
@@ -632,7 +632,7 @@ 
             }
             if (apply_filters('FHEE__EE_Session___perform_session_id_hash_check', WP_DEBUG)) {
                 $hash_check = $this->cache_storage->get(
-                    EE_Session::hash_check_prefix . $this->_sid,
+                    EE_Session::hash_check_prefix.$this->_sid,
                     false
                 );
                 if ($hash_check && $hash_check !== md5($session_data)) {
@@ -642,7 +642,7 @@ 
                                 'The stored data for session %1$s failed to pass a hash check and therefore appears to be invalid.',
                                 'event_espresso'
                             ),
-                            EE_Session::session_id_prefix . $this->_sid
+                            EE_Session::session_id_prefix.$this->_sid
                         ),
                         __FILE__,
                         __FUNCTION__,
@@ -656,17 +656,17 @@ 
             $row = $wpdb->get_row(
                 $wpdb->prepare(
                     "SELECT option_value FROM {$wpdb->options} WHERE option_name = %s LIMIT 1",
-                    '_transient_' . $ssn_key
+                    '_transient_'.$ssn_key
                 )
             );
             $session_data = is_object($row) ? $row->option_value : null;
             if ($session_data) {
                 $session_data = preg_replace_callback(
                     '!s:(d+):"(.*?)";!',
-                    function ($match) {
+                    function($match) {
                         return $match[1] === strlen($match[2])
                             ? $match[0]
-                            : 's:' . strlen($match[2]) . ':"' . $match[2] . '";';
+                            : 's:'.strlen($match[2]).':"'.$match[2].'";';
                     },
                     $session_data
                 );
@@ -677,7 +677,7 @@ 
         $session_data = $this->encryption instanceof EE_Encryption
             ? $this->encryption->base64_string_decode($session_data)
             : $session_data;
-        if (! is_array($session_data)) {
+        if ( ! is_array($session_data)) {
             try {
                 $session_data = maybe_unserialize($session_data);
             } catch (Exception $e) {
@@ -691,21 +691,21 @@ 
                       . '</pre><br>'
                       . $this->find_serialize_error($session_data)
                     : '';
-                $this->cache_storage->delete(EE_Session::session_id_prefix . $this->_sid);
+                $this->cache_storage->delete(EE_Session::session_id_prefix.$this->_sid);
                 throw new InvalidSessionDataException($msg, 0, $e);
             }
         }
         // just a check to make sure the session array is indeed an array
-        if (! is_array($session_data)) {
+        if ( ! is_array($session_data)) {
             // no?!?! then something is wrong
             $msg = esc_html__(
                 'The session data is missing, invalid, or corrupted.',
                 'event_espresso'
             );
             $msg .= WP_DEBUG
-                ? '<br><pre>' . print_r($session_data, true) . '</pre><br>' . $this->find_serialize_error($session_data)
+                ? '<br><pre>'.print_r($session_data, true).'</pre><br>'.$this->find_serialize_error($session_data)
                 : '';
-            $this->cache_storage->delete(EE_Session::session_id_prefix . $this->_sid);
+            $this->cache_storage->delete(EE_Session::session_id_prefix.$this->_sid);
             throw new InvalidSessionDataException($msg);
         }
         if (isset($session_data['transaction']) && absint($session_data['transaction']) !== 0) {
@@ -732,7 +732,7 @@ 
         if (isset($_REQUEST['EESID'])) {
             $session_id = sanitize_text_field($_REQUEST['EESID']);
         } else {
-            $session_id = md5(session_id() . get_current_blog_id() . $this->_get_sid_salt());
+            $session_id = md5(session_id().get_current_blog_id().$this->_get_sid_salt());
         }
         return apply_filters('FHEE__EE_Session___generate_session_id__session_id', $session_id);
     }
@@ -835,19 +835,19 @@ 
                     $page_visit = $this->_get_page_visit();
                     if ($page_visit) {
                         // set pages visited where the first will be the http referrer
-                        $this->_session_data['pages_visited'][ $this->_time ] = $page_visit;
+                        $this->_session_data['pages_visited'][$this->_time] = $page_visit;
                         // we'll only save the last 10 page visits.
                         $session_data['pages_visited'] = array_slice($this->_session_data['pages_visited'], -10);
                     }
                     break;
                 default:
                     // carry any other data over
-                    $session_data[ $key ] = $this->_session_data[ $key ];
+                    $session_data[$key] = $this->_session_data[$key];
             }
         }
         $this->_session_data = $session_data;
         // creating a new session does not require saving to the db just yet
-        if (! $new_session) {
+        if ( ! $new_session) {
             // ready? let's save
             if ($this->_save_session_to_db()) {
                 return true;
@@ -901,7 +901,7 @@ 
         }
         $transaction = $this->transaction();
         if ($transaction instanceof EE_Transaction) {
-            if (! $transaction->ID()) {
+            if ( ! $transaction->ID()) {
                 $transaction->save();
             }
             $this->_session_data['transaction'] = $transaction->ID();
@@ -915,14 +915,14 @@ 
         // maybe save hash check
         if (apply_filters('FHEE__EE_Session___perform_session_id_hash_check', WP_DEBUG)) {
             $this->cache_storage->add(
-                EE_Session::hash_check_prefix . $this->_sid,
+                EE_Session::hash_check_prefix.$this->_sid,
                 md5($session_data),
                 $this->session_lifespan->inSeconds()
             );
         }
         // we're using the Transient API for storing session data,
         return $this->cache_storage->add(
-            EE_Session::session_id_prefix . $this->_sid,
+            EE_Session::session_id_prefix.$this->_sid,
             $session_data,
             $this->session_lifespan->inSeconds()
         );
@@ -936,7 +936,7 @@ 
      */
     public function _get_page_visit()
     {
-        $page_visit = home_url('/') . 'wp-admin/admin-ajax.php';
+        $page_visit = home_url('/').'wp-admin/admin-ajax.php';
         // check for request url
         if (isset($_SERVER['REQUEST_URI'])) {
             $http_host = '';
@@ -952,14 +952,14 @@ 
             // check for page_id in SERVER REQUEST
             if (isset($_REQUEST['page_id'])) {
                 // rebuild $e_reg without any of the extra parameters
-                $page_id = '?page_id=' . esc_attr($_REQUEST['page_id']) . '&amp;';
+                $page_id = '?page_id='.esc_attr($_REQUEST['page_id']).'&amp;';
             }
             // check for $e_reg in SERVER REQUEST
             if (isset($_REQUEST['ee'])) {
                 // rebuild $e_reg without any of the extra parameters
-                $e_reg = 'ee=' . esc_attr($_REQUEST['ee']);
+                $e_reg = 'ee='.esc_attr($_REQUEST['ee']);
             }
-            $page_visit = rtrim($http_host . $request_uri . $page_id . $e_reg, '?');
+            $page_visit = rtrim($http_host.$request_uri.$page_id.$e_reg, '?');
         }
         return $page_visit !== home_url('/wp-admin/admin-ajax.php') ? $page_visit : '';
     }
@@ -997,7 +997,7 @@ 
 // <span style="color:#2EA2CC">' . __CLASS__ . '</span>::<span style="color:#E76700">' . __FUNCTION__ . '( ' . $class . '::' . $function . '() )</span><br/>
 // <span style="font-size:9px;font-weight:normal;">' . __FILE__ . '</span>    <b style="font-size:10px;">  ' . __LINE__ . ' </b>
 // </h3>';
-        do_action('AHEE_log', __FILE__, __FUNCTION__, 'session cleared by : ' . $class . '::' . $function . '()');
+        do_action('AHEE_log', __FILE__, __FUNCTION__, 'session cleared by : '.$class.'::'.$function.'()');
         $this->reset_cart();
         $this->reset_checkout();
         $this->reset_transaction();
@@ -1019,7 +1019,7 @@ 
     public function reset_data($data_to_reset = array(), $show_all_notices = false)
     {
         // if $data_to_reset is not in an array, then put it in one
-        if (! is_array($data_to_reset)) {
+        if ( ! is_array($data_to_reset)) {
             $data_to_reset = array($data_to_reset);
         }
         // nothing ??? go home!
@@ -1039,11 +1039,11 @@ 
         // since $data_to_reset is an array, cycle through the values
         foreach ($data_to_reset as $reset) {
             // first check to make sure it is a valid session var
-            if (isset($this->_session_data[ $reset ])) {
+            if (isset($this->_session_data[$reset])) {
                 // then check to make sure it is not a default var
-                if (! array_key_exists($reset, $this->_default_session_vars)) {
+                if ( ! array_key_exists($reset, $this->_default_session_vars)) {
                     // remove session var
-                    unset($this->_session_data[ $reset ]);
+                    unset($this->_session_data[$reset]);
                     if ($show_all_notices) {
                         EE_Error::add_success(
                             sprintf(
@@ -1144,7 +1144,7 @@ 
             // or use that for the new transient cleanup query limit
             add_filter(
                 'FHEE__TransientCacheStorage__clearExpiredTransients__limit',
-                function () use ($expired_session_transient_delete_query_limit) {
+                function() use ($expired_session_transient_delete_query_limit) {
                     return $expired_session_transient_delete_query_limit;
                 }
             );
@@ -1162,7 +1162,7 @@ 
         $error = '<pre>';
         $data2 = preg_replace_callback(
             '!s:(\d+):"(.*?)";!',
-            function ($match) {
+            function($match) {
                 return ($match[1] === strlen($match[2]))
                     ? $match[0]
                     : 's:'
@@ -1174,13 +1174,13 @@ 
             $data1
         );
         $max = (strlen($data1) > strlen($data2)) ? strlen($data1) : strlen($data2);
-        $error .= $data1 . PHP_EOL;
-        $error .= $data2 . PHP_EOL;
+        $error .= $data1.PHP_EOL;
+        $error .= $data2.PHP_EOL;
         for ($i = 0; $i < $max; $i++) {
-            if (@$data1[ $i ] !== @$data2[ $i ]) {
-                $error .= 'Difference ' . @$data1[ $i ] . ' != ' . @$data2[ $i ] . PHP_EOL;
-                $error .= "\t-> ORD number " . ord(@$data1[ $i ]) . ' != ' . ord(@$data2[ $i ]) . PHP_EOL;
-                $error .= "\t-> Line Number = $i" . PHP_EOL;
+            if (@$data1[$i] !== @$data2[$i]) {
+                $error .= 'Difference '.@$data1[$i].' != '.@$data2[$i].PHP_EOL;
+                $error .= "\t-> ORD number ".ord(@$data1[$i]).' != '.ord(@$data2[$i]).PHP_EOL;
+                $error .= "\t-> Line Number = $i".PHP_EOL;
                 $start = ($i - 20);
                 $start = ($start < 0) ? 0 : $start;
                 $length = 40;
@@ -1195,7 +1195,7 @@ 
                 $error .= "\t-> Section Data1  = ";
                 $error .= substr_replace(
                     substr($data1, $start, $length),
-                    "<b style=\"color:green\">{$data1[ $i ]}</b>",
+                    "<b style=\"color:green\">{$data1[$i]}</b>",
                     $rpoint,
                     $rlength
                 );
@@ -1203,7 +1203,7 @@ 
                 $error .= "\t-> Section Data2  = ";
                 $error .= substr_replace(
                     substr($data2, $start, $length),
-                    "<b style=\"color:red\">{$data2[ $i ]}</b>",
+                    "<b style=\"color:red\">{$data2[$i]}</b>",
                     $rpoint,
                     $rlength
                 );
@@ -1234,7 +1234,7 @@ 
     public function garbageCollection()
     {
         // only perform during regular requests if last garbage collection was over an hour ago
-        if (! (defined('DOING_AJAX') && DOING_AJAX) && (time() - HOUR_IN_SECONDS) >= $this->_last_gc) {
+        if ( ! (defined('DOING_AJAX') && DOING_AJAX) && (time() - HOUR_IN_SECONDS) >= $this->_last_gc) {
             $this->_last_gc = time();
             $this->updateSessionSettings(array('last_gc' => $this->_last_gc));
             /** @type WPDB $wpdb */
@@ -1269,7 +1269,7 @@ 
                 // AND option_value < 1508368198 LIMIT 50
                 $expired_sessions = $wpdb->get_col($SQL);
                 // valid results?
-                if (! $expired_sessions instanceof WP_Error && ! empty($expired_sessions)) {
+                if ( ! $expired_sessions instanceof WP_Error && ! empty($expired_sessions)) {
                     $this->cache_storage->deleteMany($expired_sessions, true);
                 }
             }