can I use codeigniter and redis to store session - codeigniter

Question

I use codeigniter 3 for my project, and I want to use redis to store session
to use it with nodejs and mysql for real-time notification system
i installed redis on my server and test it with nodejs is work good

Answer 1

I don't know if you are still looking for the answer(would help others too) but here's a good link (https://simplapi.wordpress.com/2012/04/13/php-and-node-js-session-share-redi/)
that explains serializing and de-serializing session data as json. I have done modification in Codeigniter's library Session_redis_driver.php to encode and decode so I can use it in Nodejs. I'd be glad if someone can validate this code and point any pitfalls or unhandled exceptions.
Modification in "read" method
public function read($session_id)
{
if (isset($this->_redis) && $this->_get_lock($session_id))
{
// Needed by write() to detect session_regenerate_id() calls
$this->_session_id = $session_id;
$session_data = json_decode($this->_redis->get($this->_key_prefix.$session_id),TRUE);
is_array($session_data)
? $this->_key_exists = TRUE
: $session_data = '';
$this->_fingerprint = md5(json_encode($session_data));
$tmp = $_SESSION;
$_SESSION = $session_data;
$new_data = session_encode();
$_SESSION = $tmp;
return $new_data;
}
return $this->_fail();
}
So far this is working without exceptions.
In write method the following changes have been done.
if (isset($this->_lock_key))
{
$this->_redis->setTimeout($this->_lock_key, 300);
$tmp = $_SESSION;
session_decode($session_data);
$new_data = $_SESSION;
$_SESSION = $tmp;
if ($this->_fingerprint !== ($fingerprint = md5(json_encode($new_data))) OR $this->_key_exists === FALSE)
{
if ($this->_redis->set($this->_key_prefix.$session_id, json_encode($new_data), $this->_config['expiration']))
{
$this->_fingerprint = $fingerprint;
$this->_key_exists = TRUE;
return $this->_success;
}
return $this->_fail();
}
return ($this->_redis->setTimeout($this->_key_prefix.$session_id, $this->_config['expiration']))
? $this->_success
: $this->_fail();
}