memcacheQueue.class.php
復制代碼 代碼如下:
<?php
/**
* PHP memcache 隊列類
* @author LKK/lianq.net
* @version 0.3
* @修改說明:
* 1.放棄了之前的AB面輪值思路,使用類似數組的構造,重寫了此類.
* 2.隊列默認先進先出,但增加了反向讀取功能.
* 3.感謝網友FoxHunter提出的寶貴意見.
* @example:
* $obj = new memcacheQueue('duilie');
* $obj->add('1asdf');
* $obj->getQueueLength();
* $obj->read(10);
* $obj->get(8);
*/
class memcacheQueue{
public static $client; //memcache客戶端連接
public $access; //隊列是否可更新
private $expire; //過期時間,秒,1~2592000,即30天內
private $sleepTime; //等待解鎖時間,微秒
private $queueName; //隊列名稱,唯一值
private $retryNum; //重試次數,= 10 * 理論並發數
public $currentHead; //當前隊首值
public $currentTail; //當前隊尾值
const MAXNUM = 20000; //最大隊列數,建議上限10K
const HEAD_KEY = '_lkkQueueHead_'; //隊列首kye
const TAIL_KEY = '_lkkQueueTail_'; //隊列尾key
const VALU_KEY = '_lkkQueueValu_'; //隊列值key
const LOCK_KEY = '_lkkQueueLock_'; //隊列鎖key
/**
* 構造函數
* @param string $queueName 隊列名稱
* @param int $expire 過期時間
* @param array $config memcache配置
*
* @return <type>
*/
public function __construct($queueName ='',$expire=0,$config =''){
if(empty($config)){
self::$client = memcache_pconnect('127.0.0.1',11211);
}elseif(is_array($config)){//array('host'=>'127.0.0.1','port'=>'11211')
self::$client = memcache_pconnect($config['host'],$config['port']);
}elseif(is_string($config)){//"127.0.0.1:11211"
$tmp = explode(':',$config);
$conf['host'] = isset($tmp[0]) ? $tmp[0] : '127.0.0.1';
$conf['port'] = isset($tmp[1]) ? $tmp[1] : '11211';
self::$client = memcache_pconnect($conf['host'],$conf['port']);
}
if(!self::$client) return false;
ignore_user_abort(true);//當客戶斷開連接,允許繼續執行
set_time_limit(0);//取消腳本執行延時上限
$this->access = false;
$this->sleepTime = 1000;
$expire = empty($expire) ? 3600 : intval($expire)+1;
$this->expire = $expire;
$this->queueName = $queueName;
$this->retryNum = 1000;
$this->head_key = $this->queueName . self::HEAD_KEY;
$this->tail_key = $this->queueName . self::TAIL_KEY;
$this->lock_key = $this->queueName . self::LOCK_KEY;
$this->_initSetHeadNTail();
}
/**
* 初始化設置隊列首尾值
*/
private function _initSetHeadNTail(){
//當前隊列首的數值
$this->currentHead = memcache_get(self::$client, $this->head_key);
if($this->currentHead === false) $this->currentHead =0;
//當前隊列尾的數值
$this->currentTail = memcache_get(self::$client, $this->tail_key);
if($this->currentTail === false) $this->currentTail =0;
}
/**
* 當取出元素時,改變隊列首的數值
* @param int $step 步長值
*/
private function _changeHead($step=1){
$this->currentHead += $step;
memcache_set(self::$client, $this->head_key,$this->currentHead,false,$this->expire);
}
/**
* 當添加元素時,改變隊列尾的數值
* @param int $step 步長值
* @param bool $reverse 是否反向
* @return null
*/
private function _changeTail($step=1, $reverse =false){
if(!$reverse){
$this->currentTail += $step;
}else{
$this->currentTail -= $step;
}
memcache_set(self::$client, $this->tail_key,$this->currentTail,false,$this->expire);
}
/**
* 隊列是否為空
* @return bool
*/
private function _isEmpty(){
return (bool)($this->currentHead === $this->currentTail);
}
/**
* 隊列是否已滿
* @return bool
*/
private function _isFull(){
$len = $this->currentTail - $this->currentHead;
return (bool)($len === self::MAXNUM);
}
/**
* 隊列加鎖
*/
private function _getLock(){
if($this->access === false){
while(!memcache_add(self::$client, $this->lock_key, 1, false, $this->expire) ){
usleep($this->sleepTime);
@$i++;
if($i > $this->retryNum){//嘗試等待N次
return false;
break;
}
}
$this->_initSetHeadNTail();
return $this->access = true;
}
return $this->access;
}
/**
* 隊列解鎖
*/
private function _unLock(){
memcache_delete(self::$client, $this->lock_key, 0);
$this->access = false;
}
/**
* 獲取當前隊列的長度
* 該長度為理論長度,某些元素由於過期失效而丟失,真實長度<=該長度
* @return int
*/
public function getQueueLength(){
$this->_initSetHeadNTail();
return intval($this->currentTail - $this->currentHead);
}
/**
* 添加隊列數據
* @param void $data 要添加的數據
* @return bool
*/
public function add($data){
if(!$this->_getLock()) return false;
if($this->_isFull()){
$this->_unLock();
return false;
}
$value_key = $this->queueName . self::VALU_KEY . strval($this->currentTail +1);
$result = memcache_set(self::$client, $value_key, $data, MEMCACHE_COMPRESSED, $this->expire);
if($result){
$this->_changeTail();
}
$this->_unLock();
return $result;
}
/**
* 讀取隊列數據
* @param int $length 要讀取的長度(反向讀取使用負數)
* @return array
*/
public function read($length=0){
if(!is_numeric($length)) return false;
$this->_initSetHeadNTail();
if($this->_isEmpty()){
return false;
}
if(empty($length)) $length = self::MAXNUM;//默認所有
$keyArr = array();
if($length >0){//正向讀取(從隊列首向隊列尾)
$tmpMin = $this->currentHead;
$tmpMax = $tmpMin + $length;
for($i= $tmpMin; $i<=$tmpMax; $i++){
$keyArr[] = $this->queueName . self::VALU_KEY . $i;
}
}else{//反向讀取(從隊列尾向隊列首)
$tmpMax = $this->currentTail;
$tmpMin = $tmpMax + $length;
for($i= $tmpMax; $i >$tmpMin; $i--){
$keyArr[] = $this->queueName . self::VALU_KEY . $i;
}
}
$result = @memcache_get(self::$client, $keyArr);
return $result;
}
/**
* 取出隊列數據
* @param int $length 要取出的長度(反向讀取使用負數)
* @return array
*/
public function get($length=0){
if(!is_numeric($length)) return false;
if(!$this->_getLock()) return false;
if($this->_isEmpty()){
$this->_unLock();
return false;
}
if(empty($length)) $length = self::MAXNUM;//默認所有
$length = intval($length);
$keyArr = array();
if($length >0){//正向讀取(從隊列首向隊列尾)
$tmpMin = $this->currentHead;
$tmpMax = $tmpMin + $length;
for($i= $tmpMin; $i<=$tmpMax; $i++){
$keyArr[] = $this->queueName . self::VALU_KEY . $i;
}
$this->_changeHead($length);
}else{//反向讀取(從隊列尾向隊列首)
$tmpMax = $this->currentTail;
$tmpMin = $tmpMax + $length;
for($i= $tmpMax; $i >$tmpMin; $i--){
$keyArr[] = $this->queueName . self::VALU_KEY . $i;
}
$this->_changeTail(abs($length), true);
}
$result = @memcache_get(self::$client, $keyArr);
foreach($keyArr as $v){//取出之後刪除
@memcache_delete(self::$client, $v, 0);
}
$this->_unLock();
return $result;
}
/**
* 清空隊列
*/
public function clear(){
if(!$this->_getLock()) return false;
if($this->_isEmpty()){
$this->_unLock();
return false;
}
$tmpMin = $this->currentHead--;
$tmpMax = $this->currentTail++;
for($i= $tmpMin; $i<=$tmpMax; $i++){
$tmpKey = $this->queueName . self::VALU_KEY . $i;
@memcache_delete(self::$client, $tmpKey, 0);
}
$this->currentTail = $this->currentHead = 0;
memcache_set(self::$client, $this->head_key,$this->currentHead,false,$this->expire);
memcache_set(self::$client, $this->tail_key,$this->currentTail,false,$this->expire);
$this->_unLock();
}
/*
* 清除所有memcache緩存數據
*/
public function memFlush(){
memcache_flush(self::$client);
}
}//end class
