php实现Session存储到Redis

对于大访问量的站点使用默认的session 并不合适，我们可以将其存入数据库、或者使用redis key-value数据存储方案
首先新建一个session表

create table `sessions` (
 `sid` char(40) not null,
 `updatetime` int(20) not null,
 `data` varchar(200) not null,
 unique key `sid` (`sid`) using hash
) engine=memory default charset=utf8;

mysql 的memory引擎采用内存表，所有数据存储在内存，操作速度快

<?php
//引入数据库文件
include "db.php";
class mysessionhandler implements sessionhandlerinterface
{
  private $savepath;
  private $sessdata;
  public $expiretime;  //设置过期时间
  public $db;  //数据库
  public function __construct($hanlder =''){
     
    $this->db = database::getinstance();  
     
    //获取数据库实力 
    ///var_dump($this->db);
     
  }
   
  public function open($savepath, $sessionname)
  {
 
    return true;
  }
 
  public function close()
  {
    return true;
  }
 
  public function read($id)
  {  
    $sql ="select * from sessions where sid ='$id'";
    $result = $this->db->execute($sql);
      if(!empty($result)){
         return $this->sessdata = $result;
      }
  }
      //函数的参数 $id -> 当前会话id
      //数据data -> 序列化之后的字符串
  public function write($id, $data)
  {
    // echo $id;
    // echo $data;
    $now = time();
    $newexp = $now+$this->expiretime;  //总时间=当前时间 + 期限时间
    $sql = "select * from sessions where sid ='$id'";
    $result = $this->db->getone($sql);
    //var_dump($result);
    if($data==''||isset($data)){
      $data = $this->sessdata;
    }
      if($result){
      //如果存在则更新
  $sql ="update sessions set updatetime = '$newexp',data ='$data' where sid = '$id'";
        //echo $sql;
          $update_data =$this->db->execute($sql);
          if($update_data){
            return true;
          }
         
      }else{
      //不存在则生成生成
  $sql = "insert into sessions(sid,updatetime,data) values('$id','$now','$data')";
    $insert_data = $this->db->execute($sql);
    if($insert_data){
    return true;
        }
      }
      return false;
  }
 
  public function destroy($id)
  {    //销毁
    $sql = "delete from sessions where sid="."$id";
    $destory = $this->db->execute($sql);
    if($destory){
       return true;
    }else{
      return false;
    }
  }
 
  public function gc($sessmaxlifetime)
  {
   $t = time();
  $sql ="delete from sessions where $t - 'updatetime'>${sessmaxlifetime}";
    $data = $this->db->execute($this->tosql);
    if($data){
      return true;
    }else{
      return false;
      }
    return true;
  }
}

实例化

此处 php 手册可以有两种方法
1，实现了sessionhandlerinterface借口的对象,自php5.4可以使用
2 ，直接使用  session_set_save_handler

 //判断php版本
 if(version_compare(php_version,5.4)==1){
       
   session_set_save_handler($handler, true);
  session_start();
  }else{  
    ini_set('session.use_trans_sid',0);
    ini_set('session.use_cookies',1);
    ini_set('session.cookie_path','/');
      ini_set('session.save_handler','user');
      session_module_name('user');
      session_set_save_handler(array($session,"open"),array($session,"close"),array($session,"read"),array($session,"write"),array($session,"destory"),array($session,"gc"));
      session_start();   
     }
$_session['qq']="qq";
echo $_session['qq'];

数据库代码

<?php 
class database{
     static $instance;
    static $db;
  static function getinstance(){   
    if(self::$instance){
      return self::$instance;
    }else{
      return new database();  
    }
  }
  public function __construct(){
    self::$db = new pdo('mysql:host=localhost;dbname=session', 'root','');
  }
 
    public function getone($sql){
      $rs =self::$db->query($sql);
      @$rs->setfetchmode(pdo::fetch_assoc);//返回关联数组
      $result = $rs -> fetch();
      return $result;
    }
    public function execute($sql){
       
       
        $rs = self::$db->exec($sql);
        return $rs;
         
    } 
   
 
} 
//$data = database::getinstance();
//var_dump($data);

  使用redis 存储session

<?php
class sessionmanager{
  private $redis;
  private $sessionsavepath;
  private $sessionname;
  private $sessionexpiretime = 30;
  public function __construct(){
    $this->redis = new redis();
    $this->redis->connect('127.0.0.1',6379);  //连接redis
    $retval = session_set_save_handler(
      array($this,"open"),
      array($this,"close"),
      array($this,"read"),
      array($this,"write"),
      array($this,"destory"),
      array($this,"gc")
    );
      session_start();
  }
   
    public function open($path,$name){
      return true;
    }
    public function close(){
      return true;
    }
    public function read($id){
      $value = $this->redis->get($id);
      if($value){
        return $value;
      }else{
        return "";
      }
    }
    public function write($id,$data){
      if($this->redis->set($id,$data)){
        $this->redis->expire($id,$this->sessionexpiretime); 
         //设置过期时间
        return true;
      }
      return false;
    }
    public function destory($id){
      if($this->redis->delete($id)){
        return true;
      }
      return false;
    }
    public function gc($maxlifetime){
      return true;
    }
    //析构函数
    public function __destruct(){
      session_write_close();
    }
     
} 
$re = new sessionmanager();
$_session['name'] = "qq";
echo $_session['name'];

以上就是详细的介绍了php实现session存储到redis的方法，希望对大家的学习有所帮助。