首页 / 网页编程 / PHP / 用mysql内存表来代替php session的类

复制代码 代码如下:
<？php
/**
@Usage: use some other storage method（mysql or memcache） instead of php sessoin
@author:lein
@Version:1.0
*/
session_start（）;
if（！isset（$_SESSION["test"]））{
$_SESSION["test"]="123_lein_".date（"Y-m-d H:i:s"）;
}

class session{

//session data
private $data;
//engine,mysql or memcache
private $engine;
//php session expire time
private $sessionexpiredTime;
//current user"s session cookie value
private $sessionID;

public function session（$engineBase=NULL,$engineName="mysql",$storage_name="php_session"）{
try{
$this->sessionexpiredTime = intval（ini_get（"session.cache_expire"））*60;
}catch（Exception $Exception）{
$this->sessionexpiredTime = 1200;
}
@session_start（）;
$this->sessionID=session_id（）;
$className = $engineName."SessionEngine";
$this->engine = new $className（
array（
"storage_name"=>$storage_name,//mysql table name or memcahce key which stores data;
"expire_time"=>$this->sessionexpiredTime,
"data_too_long_instead_value" => "{__DATA IS *$* TO LONG__}"
）,
$this->sessionID,
&$engineBase
）;
$this->init（）;
$this->engine->refresh（）;
$this->engine->cleanup（）;
}
private function init（）
{
$this->data = $this->engine->get（）;
if（emptyempty（$this->data）&&！emptyempty（$_SESSION））{
$this->data = $_SESSION;
$this->engine->create（false, $this->data）;
}
else if（emptyempty（$this->data））
{
$this->engine->create（false, $this->data）;
}
}
private function __get（$nm）
{
if （isset（$this->data[$nm]）） {
$r = $this->data[$nm];
return $r;
}
else
{
return NULL;
}
}
private function __set（$nm, $val）
{
$this->data[$nm] = $val;
$this->engine->set（false, $this->data）;
}
function __destruct（）{
$this->data = NULL;
$this->engine->close（）;
$this->engine = NULL;
}
}

interface SessionEngine
{
/*
* set varibles
* @param $arr array,array（varible name=>varible value,...）
*/
public function setVariable（$arr）;
/*
* get session value
* @param $key string
*/
public function get（$key=""）;
/*
* set session value
* @param $key string
* @param $value string
*/
public function set（$key="",$value=""）;
/*
* set session value
* @param $key string
* @param $value string
*/
public function create（$key="",$value=""）;
/*
* update the session"s invalid time
* @param $key string
*/
public function refresh（$key=""）;
/*
* close mysql or memcache connection
*/
public function close（）;
/*
* delete expired sessions
*/
public function cleanup（）;
}

final class mysqlSessionEngine implements SessionEngine{
private $id="";
private $storage_name="php_session";
private $storage_name_slow="php_session_slow";
private $data_too_long_instead_value = "{__DATA IS ~ TO LONG__}";//if data is longer than $max_session_data_length and you are using mysql 4 or below,insert this value into memery table instead.
private $expire_time=1200;
private $max_session_data_length = 2048;
private $conn;
private $mysql_version;
public function mysqlSessionEngine（$arr=array（）,$key="",&$_conn）{
$this->setVariable（$arr）;
$this->id = $key;
if（emptyempty（$this->id）||strlen（$this->id）！=32）{
throw new Exception（__FILE__."->".__LINE__.": Session"s cookie name can"t be empty and it must have just 32 charactors！"）;
}
$this->conn = $_conn;
if（！$this->conn||！is_resource（$this->conn））{
throw new Exception（__FILE__."->".__LINE__.": Need a mysql connection！"）;
}
$this->mysql_version = $this->getOne（"select floor（version（））"）;
if（$this->mysql_version<5）{
$this->max_session_data_length = 255;
}
}
public function setVariable（$arr）{
if（！emptyempty（$arr）&&is_array（$arr））{
foreach（$arr as $k=>$v）{
$this->$k = $v;
if（$k=="storage_name"）{
$this->storage_name_slow = $v."_slow";
}
}
}
}
public function get（$key=""）{
if（$key==""） $key = $this->id;
$return = $this->getOne（"select value from ".$this->storage_name." where id="".$key."""）;
if（$return==$this->data_too_long_instead_value）
{
$return = $this->getOne（"select value from ".$this->storage_name_slow." where id="".$key."""）;
}
if（！$return）
{
$mysqlError = mysql_error（$this->conn）;
if（strpos（$mysqlError,"doesn"t exist"）！==false）
{
$this->initTable（）;
}
$return = array（）;
}
else
{
$return = unserialize（$return）;
}
return $return;
}
public function close（）{
@mysql_close（$this->conn）;
}
public function cleanup（）{
if（$this->mysql_version>4）{
$sql = "delete from ".$this->storage_name." while date_add（time,INTERVAL ".$this->expire_time." SECOND）<CURRENT_TIMESTAMP（）";
}else{
$sql = "delete from ".$this->storage_name." while time+".$this->expire_time."<unix_timestamp（）";
}
$this->execute（$sql）;
}
public function refresh（$key=""）{
if（$this->mysql_version>4）{
$sql = "update ".$this->storage_name." set time=CURRENT_TIMESTAMP（） where id="".$key.""";
}else{
$sql = "update ".$this->storage_name." set time=unix_timestamp（） where id="".$key.""";
}
$return = $this->execute（$sql）;
if（！$return）{
$this->initTable（）;
$return = $this->execute（$sql,true）;
}
return $return;
}
public function create（$key="",$value=""）{
if（$key==""） $key = $this->id;
if（$value ！= ""） $value = mysql_real_escape_string（serialize（$value）,$this->conn）;
if（strlen（$value）>$this->max_session_data_length） throw new Exception（__FILE__."->".__LINE__.": Session data is long than max allow length（".$this->max_session_data_length."）！"）;
if（$this->mysql_version>4）{
$sql = "replace into ".$this->storage_name." set value="".$value."",id="".$key."",time=CURRENT_TIMESTAMP（）";
}else{
$sql = "replace into ".$this->storage_name." set value="".$value."",id="".$key."",time=unix_timestamp（）";
}
$return = $this->execute（$sql）;
if（！$return）{
$this->initTable（）;
$return = $this->execute（$sql,true）;
}
return $return;
}
public function set（$key="",$value=""）{
if（$key==""） $key = $this->id;
if（$value ！= ""） $value = mysql_real_escape_string（serialize（$value）,$this->conn）;
$sql = "update ".$this->storage_name." set value="".$value."" where id="".$key.""";
if（strlen（$value）>$this->max_session_data_length）
{
if（$this->mysql_version>4）{
throw new Exception（__FILE__."->".__LINE__.": Session data is long than max allow length（".$this->max_session_data_length."）！"）;
}
$sql = "replace into ".$this->storage_name_slow." set value="".$value."",id="".$key."",time=unix_timestamp（）";
$this->execute（$sql,true）;
$sql = "update ".$this->storage_name." set value="".$this->data_too_long_instead_value."" where id="".$key.""";
}
$return = $this->execute（$sql）;
if（！$return）{
$this->initTable（）;
$return = $this->execute（$sql,true）;
}
return $return;
}
private function initTable（）{
if（$this->mysql_version>4）{
$sql = "
CREATE TABLE if not exists `".$this->storage_name."` （
`id` char（32） NOT NULL default "ERR",
`value` VARBINARY（".$this->max_session_data_length."） NULL,
`time` timestamp NOT NULL default CURRENT_TIMESTAMP on update CURRENT_TIMESTAMP,
PRIMARY KEY （`id`）,
KEY `time` （`time`）
） ENGINE=MEMORY;
";
}else{
$sqlSlow = "
CREATE TABLE if not exists `".$this->storage_name."_slow` （
`id` char（32） NOT NULL default "ERR",
`value` text NULL,
`time` int（10） not null default "0",
PRIMARY KEY （`id`）,
KEY `time` （`time`）
） ENGINE=MyISAM;
";
$this->execute（$sqlSlow,true）;

$sql = "
CREATE TABLE if not exists `".$this->storage_name."` （
`id` char（32） NOT NULL default "ERR",
`value` VARCHAR（255） NULL,
`time` int（10） not null default "0",
PRIMARY KEY （`id`）,
KEY `time` （`time`）
） ENGINE=MEMORY;
";
}
return $this->execute（$sql,true）;
}
private function execute（$sql,$die=false）
{
if（$die）
{
mysql_query（$sql,$this->conn） or die（"exe Sql error:<br>".mysql_error（）."<br>".$sql."<hr>"）;
}
else
{
mysql_query（$sql,$this->conn）;

if（mysql_error（））{
return false;
}else{
return true;
}
}
}
private function getOne（$sql,$die=false）{
$rs = $this->query（$sql,$die）;
if（$rs && （$one = mysql_fetch_row（$rs）） ）{
return $one[0];
}else{
return false;
}
}
private function query（$sql,$die=false）{
if（$die）
$rs = mysql_query（$sql,$this->conn） or die（"query Sql error:<br>".mysql_error（）."<br>".$sql."<hr>"）;
else
$rs = mysql_query（$sql,$this->conn）;
return $rs;
}
}

$lnk = mysql_connect（"localhost", "root", "123456"）
or die （"Not connected : " . mysql_error（））;

// make foo the current db
mysql_select_db（"test", $lnk） or die （"Can"t use foo : " . mysql_error（））;
$S = new session（$lnk）;
if（！$S->last）{
$S->last = time（）;
}
echo "First visit at ".$S->last."<br>";
if（！$S->lastv）{
$S->lastv = 0;
}
$S->lastv++;
echo "lastv=".$S->lastv."<br>";
echo "test=".$S->test."<br>";
if（isset（$_GET["max"]））{
$S->boom = str_repeat（"OK",255）;
}
if（isset（$_GET["boom"]））{
$S->boom = $_GET["boom"];
}
echo "boom=".$S->boom."<br>";
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