From c9efaced2fd453bf4c2fcefd31ee1a9afdf8ff16 Mon Sep 17 00:00:00 2001 From: Andrey Andreev Date: Tue, 2 Sep 2014 15:19:01 +0300 Subject: feature/session (#3073): Add Memcached session driver --- .../Session/drivers/Session_memcached_driver.php | 287 +++++++++++++++++++++ 1 file changed, 287 insertions(+) create mode 100644 system/libraries/Session/drivers/Session_memcached_driver.php diff --git a/system/libraries/Session/drivers/Session_memcached_driver.php b/system/libraries/Session/drivers/Session_memcached_driver.php new file mode 100644 index 000000000..c6ad56511 --- /dev/null +++ b/system/libraries/Session/drivers/Session_memcached_driver.php @@ -0,0 +1,287 @@ +_save_path)) + { + log_message('error', 'Session: No Memcached save path configured.'); + } + + if ($this->_match_ip === TRUE) + { + $this->_key_prefix .= $_SERVER['REMOTE_ADDR'].':'; + } + } + + // ------------------------------------------------------------------------ + + public function open($save_path, $name) + { + $this->_memcached = new Memcached(); + $server_list = array(); + foreach ($this->_memcached->getServerList() as $server) + { + $server_list[] = $server['host'].':'.$server['port']; + } + + if ( ! preg_match_all('#,?([^,:]+)\:(\d{1,5})(?:\:(\d+))?#', $this->_save_path, $matches, PREG_SET_ORDER)) + { + $this->_memcached = NULL; + log_message('error', 'Session: Invalid Memcached save path format: '.$this->_save_path); + return FALSE; + } + + foreach ($matches as $match) + { + // If Memcached already has this server (or if the port is invalid), skip it + if (in_array($match[1].':'.$match[2], $server_list, TRUE)) + { + log_message('debug', 'Session: Memcached server pool already has '.$match[1].':'.$match[2]); + continue; + } + + if ( ! $this->_memcached->addServer($match[1], $match[2], isset($match[3]) ? $match[3] : 0)) + { + log_message('error', 'Could not add '.$match[1].':'.$match[2].' to Memcached server pool.'); + } + else + { + $server_list[] = $server['host'].':'.$server['port']; + } + } + + if (empty($server_list)) + { + log_message('error', 'Session: Memcached server pool is empty.'); + return FALSE; + } + + return TRUE; + } + + // ------------------------------------------------------------------------ + + public function read($session_id) + { + if (isset($this->_memcached) && $this->_get_lock($session_id)) + { + $session_data = (string) $this->_memcached->get($this->_key_prefix.$session_id); + $this->_fingerprint = md5($session_data); + return $session_data; + } + + return FALSE; + } + + public function write($session_id, $session_data) + { + if (isset($this->_memcached, $this->_lock_key)) + { + $this->_memcached->replace($this->_lock_key, time(), 5); + if ($this->_fingerprint !== ($fingerprint = md5($session_data))) + { + if ($this->_memcached->set($this->_key_prefix.$session_id, $session_data, $this->_expiration)) + { + $this->_fingerprint = $fingerprint; + return TRUE; + } + + return FALSE; + } + + return $this->_memcached->touch($this->_key_prefix.$session_id, $this->_expiration); + } + + return FALSE; + } + + // ------------------------------------------------------------------------ + + public function close() + { + if (isset($this->_memcached)) + { + isset($this->_lock_key) && $this->_memcached->delete($this->_lock_key); + if ( ! $this->_memcached->quit()) + { + return FALSE; + } + + $this->_memcached = NULL; + return TRUE; + } + + return FALSE; + } + + // ------------------------------------------------------------------------ + + public function destroy($session_id) + { + if (isset($this->_memcached, $this->_lock_key)) + { + $this->_memcached->delete($this->_key_prefix.$session_id); + return ($this->_cookie_destroy() && $this->close()); + } + + return $this->close(); + } + + // ------------------------------------------------------------------------ + + public function gc($maxlifetime) + { + return TRUE; + } + + // ------------------------------------------------------------------------ + + protected function _get_lock($session_id) + { + if (isset($this->_lock_key)) + { + return $this->_memcached->replace($this->_lock_key, time(), 5); + } + + $lock_key = $this->_key_prefix.$session_id.':lock'; + if ( ! ($ts = $this->_memcached->get($lock_key))) + { + if ( ! $this->_memcached->set($lock_key, TRUE, 5)) + { + log_message('error', 'Session: Error while trying to obtain lock for '.$this->_key_prefix.$session_id); + return FALSE; + } + + $this->_lock_key = $lock_key; + $this->_lock = TRUE; + return TRUE; + } + + // Another process has the lock, we'll try to wait for it to free itself ... + $attempt = 0; + while ($attempt++ < 5) + { + usleep(((time() - $ts) * 1000000) - 20000); + if (($ts = $this->_memcached->get($lock_key)) < time()) + { + continue; + } + + if ( ! $this->_memcached->set($lock_key, time(), 5)) + { + log_message('error', 'Session: Error while trying to obtain lock for '.$this->_key_prefix.$session_id); + return FALSE; + } + + $this->_lock_key = $lock_key; + break; + } + + if ($attempt === 5) + { + log_message('error', 'Session: Unable to obtain lock for '.$this->_key_prefix.$session_id.' after 5 attempts, aborting.'); + return FALSE; + } + + $this->_lock = TRUE; + return TRUE; + } + + // ------------------------------------------------------------------------ + + protected function _release_lock() + { + if (isset($this->_memcached, $this->_lock_key) && $this->_lock) + { + if ( ! $this->_memcached->delete($this->_lock_key) && $this->_memcached->getResultCode() !== Memcached::RES_NOTFOUND) + { + log_message('error', 'Session: Error while trying to free lock for '.$this->_key_prefix.$session_id); + return FALSE; + } + + $this->_lock_key = NULL; + $this->_lock = FALSE; + } + + return TRUE; + } + +} + +/* End of file Session_memcached_driver.php */ +/* Location: ./system/libraries/Session/drivers/Session_memcached_driver.php */ \ No newline at end of file -- cgit v1.2.3-24-g4f1b