PHP实现大文件切割上传

/**
 * 取值简便方法
 * @param  String $query   请求参数格式如：post.arg、get.arg、server.arg、cookie.arg
 * @param  mixed $default  默认值
 * @return mixed           获取到的值或默认值
 */
function helper($query, $default=null){
    $qus = explode('.', $query);
    if(count($qus) === 1){
        $type = strtolower($_SERVER['REQUEST_METHOD']);
    }else{
        $type = strtolower($qus[0]);
        $query = $qus[1];
    }
    switch ($type) {
        case 'post':
            return isset($_POST[$query]) ? $_POST[$query] : $default;
        case 'get':
            return isset($_GET[$query]) ? $_GET[$query] : $default;
        case 'server':
            return isset($_SERVER[$query]) ? $_SERVER[$query] : $default;
        case 'cookie':
            return isset($_COOKIE[$query]) ? $_COOKIE[$query] : $default;
        default:
            return $default;
    }
}
 
header('Content-type: application/json');
//上传文件
if ($_SERVER['REQUEST_METHOD'] === 'POST'){
 
  if (!empty($_FILES)){
    foreach ($_FILES as $file) {
      $uploader = new Uploader();
      $info = $uploader->upload($file);
      //目前块只包含一个文件
      echo json_encode($uploader->getResult());
      die;
    }
  }
}else if($_SERVER['REQUEST_METHOD'] === 'GET'){
  //断点上传
  //获取文件基本信息
  $uploader = new Uploader();
  $upload = $uploader->getUploadInfo();
  echo json_encode($upload);
}

/**
 * 分隔文件处理
 */
class Uploader{
 
  /**
   * 临时文件上传保存目录
   */
  const UPLOAD_TMP_PATH = './_tmp/';
  /**
   * 合并后的文件保存目录
   */
  const UPLOAD_REAL_PATH = './upload/';
 
  /**
   * 文件上传成功状态
   */
  const STATUS_SUCCESS = 0;
 
  /**
   * 文件上传失败状态
   */
  const STATUS_MOVE_ERROR = 1;
 
  /**
   * [$error 错误消息]
   * @var string
   */
  protected $error = '';
  /**
   * [$code 消息代码]
   * @var integer
   */
  protected $code = 0;
 
  /**
   * [
   * __construct 构造方法,主要获取上传的基本信息.和服务端的数据进行对比.
   * NOTE:可以结合文件的hash值实现文件秒传功能,原理差不多了
   * ]
   */
  public function __construct(){
    $this->config = array(
      'filename' => helper('filename'),
      'filesize' => intval(helper('filesize')),
      'filetype' => helper('filetype'),
      'modified' => intval(helper('modified')),
      'trunksize'=> intval(helper('trunksize'))
    );
    $this->hash = md5(serialize($this->config));
  }
 
  /**
   * [upload 上传文件]
   * @param  [type] $file [$_FILES[0]前端上传的FILE]
   * @return [type]       [description]
   */
  public function upload($file){
    // print_r($this->config);
    $trunk = intval(helper('post.trunk'));
    $total = helper('post.total');
    // print_r($file);
    //文件移动成功,记录文件上传指针
    $trunkname = self::UPLOAD_TMP_PATH . $this->hash . '.part.'.$trunk;
 
    if(@move_uploaded_file($file['tmp_name'], $trunkname)){
 
      static::log('success','文件'.$this->config['filename'].',块'.$trunk.'移动成功');
 
      $upload = $this->_uploadSuccess($trunk,$trunkname);
      if(count($upload) == $total){
        //合并文件
        $this->combineTrunkFile();
      }
      
      $this->setCode(self::STATUS_SUCCESS,'ok');
      return true;
    }
 
    static::log('error','文件'.$this->config['filename'].',块'.$trunk.'移动失败');
 
    $this->setCode(self::STATUS_MOVE_ERROR,'移动上传块'.$trunk.'失败');
    return false;
  }
 
  /**
   * [setCode 设置返回消息]
   * @param [type] $code [code]
   * @param string $msg  [消息]
   */
  protected function setCode($code,$msg=''){
    $this->error = $msg;
    $this->code = $code;
  }
 
  /**
   * [getResult 获取结果]
   * @return [type] [result]
   */
  public function getResult(){
    return [
      'code'  => $this->code,
      'error' => $this->error
    ];
  }
 
  /**
   * [_uploadSuccess 记录上传成功的块]
   * @param  [type] $trunk [块id]
   * @return [type]        [返回上传所有已经上传的块]
   */
  protected function _uploadSuccess($trunk,$trunkname){
 
    $log = self::UPLOAD_TMP_PATH .$this->hash.'.log';
 
    $uploadLog = $this->getUploadInfo();
 
 
    if(false === array_key_exists($trunk, $uploadLog['record']) 
      || $uploadLog['record'][$trunk] < $uploadLog['trunksize']){
      $uploadLog['record'][ $trunk ] = filesize($trunkname);
      file_put_contents( $log,serialize($uploadLog) );
    }
 
    return $uploadLog['record'];
  }
 
  /**
   * [getUploadInfo 获取服务端保存的文件上传信息]
   * @return [type] [description]
   */
  public function getUploadInfo(){
    $log = self::UPLOAD_TMP_PATH .$this->hash.'.log';
 
    if(file_exists($log)){
      $uploadLog = unserialize(file_get_contents($log));
    }else{
      $uploadLog = $this->config;
      $uploadLog['total'] = helper('post.total',0);
      $uploadLog['record'] = [];
    }
 
    return $uploadLog;
  }
 
  /**
   * [combineTrunkFile 合并文件]
   * @param  [type] $config [文件碎片信息]
   * @return [type]         [description]
   */
  public function combineTrunkFile(){
    $config = $this->getUploadInfo();
 
    $partname = self::UPLOAD_TMP_PATH . $this->hash . '.part.';
 
    $fp = fopen(self::UPLOAD_REAL_PATH . $config['filename'], 'w');
    //注意,切割的文件编号从1开始的
    for ($i=1; $i <= $config['total']; $i++) { 
      fwrite($fp, file_get_contents( $partname.$i ));
      //产出文件
      unlink($partname.$i);
    }
 
    static::log('success','文件'.$config['filename'].'合并成功');
 
    fclose($fp);
  }
 
  /**
   * [log 记录上传日志]
   * @param  string $type [description]
   * @param  string $msg  [description]
   * @return [type]       [description]
   */
  public static function log($type='', $msg=''){
    $str =  sprintf('[%s] %s => %s'.PHP_EOL,date('Y-m-d H:i:s'),strtoupper($type),$msg);
 
    if (($fp = fopen('upload_log.log', 'a+')) !== false) {
          fputs($fp, $str);
          fclose($fp);
      }
 
  }
 
}