redis + php + session

1.php

<?php
$vcap_services = json_decode( getenv( "VCAP_SERVICES" ) );
$credentials = $vcap_services->{"redis-2.2"}[0]->credentials;
$host = $credentials->host;
$port = $credentials->port;
$pass = $credentials->password;

ini_set( 'session.save_handler', 'redis' );
ini_set( 'session.save_path', "tcp://{$host}:{$port}?auth={$pass}" );

session_start();

3.php

<?php
require_once 'RedisSessionHandler.php';

$vcap_services = json_decode( getenv( "VCAP_SERVICES" ) );
$credentials = $vcap_services->{"redis-2.2"}[0]->credentials;
$host = $credentials->host;
$port = $credentials->port;
$pass = $credentials->password;

$rsh = new RedisSessionHandler( $host, $port, $pass );
session_set_save_handler(
  array( $rsh, 'open' ),
  array( $rsh, 'close' ),
  array( $rsh, 'read' ),
  array( $rsh, 'write' ),
  array( $rsh, 'destroy' ),
  array( $rsh, 'gc' )
);
register_shutdown_function( 'session_write_close' );

session_start();

RedisSessionHandler.php

<?php
// RedisSessionHandler.php
class RedisSessionHandler
{
  const PREFIX = 'REDISSESS:';
  const TIMEOUT = 2.0;
  const SESS_TIMEOUT = 1200;

  public function __construct( $host, $port, $password ) {
    $this->_redis = new Redis();
    $this->_host = $host;
    $this->_port = $port;
    $this->_password = $password;
    return true;
  }

  public function open( $savePath, $sessionName ) {
    $this->_redis->connect( $this->_host, $this->_port, self::TIMEOUT );
    $this->_redis->setOption( Redis::OPT_PREFIX, self::PREFIX );
    $this->_redis->auth( $this->_password );
    return true;
  }

  public function close() {
    return true;
  }

  public function read( $id ){
    return gzinflate( $this->_redis->get( $id ) );
  }

  public function write( $id, $data ){
    $this->_redis->setex( $id, self::SESS_TIMEOUT, gzdeflate( $data, 9 ) );
    return true;
  }

  public function destroy( $id ){
    $this->_redis->delete( $id );
    return true;
  }

  public function gc( $maxlifetime ) {
    return true;
  }
}