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。