PHP一致性hash分布式算法封装类定义与用法示例

本文实例讲述了PHP一致性hash分布式算法封装类定义与用法。分享给大家供大家参考，具体如下：

一、无虚拟节点实现

myHash($server. '#1');
    if(!isset($this->_serverList[$hash])) {
      for ($i = 1; $i <= $this->_virtual_node_num; $i++) {
        $hash = $this->myHash($server . '#' . $i);
        $this->_serverList[$hash] = $server;
      }
    }
    $this->_isSorted = false;
    return true;
  }
  //删除服务器
  function removeServer($server){
    for ($i = 1; $i <= $this->_virtual_node_num; $i++) {
      $hash = $this->myHash($server . '#' . $i);
      unset($this->_serverList[$hash]);
    }
    $this->_isSorted = false;
    return true;
  }
  //获取服务器
  function lookup($key){
    $hash =$this->myHash($key);
    if(!$this->_isSorted){
      krsort($this->_serverList,SORT_NUMERIC);
      $this->_isSorted = true;
    }
    foreach($this->_serverList as $pos=>$server){
      if($hash >= $pos) return $server;
    }
    return end($this->_serverList);
  }
  public function getServerList(){
    krsort($this->_serverList,SORT_NUMERIC);
    return $this->_serverList;
  }
}
//demo test
$hserver = new FlexiHash();
//添加服务器
$hserver->addServer('192.168.1.1');
$hserver->addServer('192.168.1.2');
$hserver->addServer('192.168.1.3');
$hserver->addServer('192.168.1.4');
$hserver->addServer('192.168.1.5');
$key1='Key1111';
$key2='Key2222';
$key2='Key3333';
$key2='Key4444';
$key2='Key5555';
$key2='Key6666';
echo "save key1 in server: ".$hserver->lookup($key1).PHP_EOL;
echo "save key2 in server: ".$hserver->lookup($key2).PHP_EOL;
echo "save key1 in server: ".$hserver->lookup($key3).PHP_EOL;
echo "save key2 in server: ".$hserver->lookup($key4).PHP_EOL;
echo "save key1 in server: ".$hserver->lookup($key5).PHP_EOL;
echo "save key2 in server: ".$hserver->lookup($key6).PHP_EOL;
echo "================================================".PHP_EOL;
//移除服务器 key值将自动转义到下一台服务器
$hserver->removeServer('192.168.1.4');
echo "save key1 in server: ".$hserver->lookup($key1).PHP_EOL;
echo "save key2 in server: ".$hserver->lookup($key2).PHP_EOL;
echo "save key1 in server: ".$hserver->lookup($key3).PHP_EOL;
echo "save key2 in server: ".$hserver->lookup($key4).PHP_EOL;
echo "save key1 in server: ".$hserver->lookup($key5).PHP_EOL;
echo "save key2 in server: ".$hserver->lookup($key6).PHP_EOL;
echo "================================================".PHP_EOL;
//恢复故障服务器 key值将恢复原来服务器
$hserver->addServer('192.168.1.4');
echo "save key1 in server: ".$hserver->lookup($key1).PHP_EOL;
echo "save key2 in server: ".$hserver->lookup($key2).PHP_EOL;
echo "save key1 in server: ".$hserver->lookup($key3).PHP_EOL;
echo "save key2 in server: ".$hserver->lookup($key4).PHP_EOL;
echo "save key1 in server: ".$hserver->lookup($key5).PHP_EOL;
echo "save key2 in server: ".$hserver->lookup($key6).PHP_EOL;

二、运行结果：

save key1 in server: 192.168.1.4
save key2 in server: 192.168.1.4
save key1 in server: 192.168.1.3
save key2 in server: 192.168.1.3
save key1 in server: 192.168.1.3
save key2 in server: 192.168.1.3
================================================
save key1 in server: 192.168.1.2
save key2 in server: 192.168.1.5
save key1 in server: 192.168.1.3
save key2 in server: 192.168.1.3
save key1 in server: 192.168.1.3
save key2 in server: 192.168.1.3
================================================
save key1 in server: 192.168.1.4
save key2 in server: 192.168.1.4
save key1 in server: 192.168.1.3
save key2 in server: 192.168.1.3
save key1 in server: 192.168.1.3
save key2 in server: 192.168.1.3

PS：这里再为大家提供2款hash相关在线工具供大家参考使用：

在线散列/哈希算法加密工具：
http://tools.jb51.net/password/hash_encrypt

在线MD5/hash/SHA-1/SHA-2/SHA-256/SHA-512/SHA-3/RIPEMD-160加密工具：
http://tools.jb51.net/password/hash_md5_sha

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希望本文所述对大家PHP程序设计有所帮助。