PHP + JS 实现大文件分割上传

服务器上传文件会有一定的限制。避免内存消耗过大影响性能,在 php.ini 配置文件中,有几个影响参数:

upload_max_filesize = 2M //PHP最大能接受的文件大小
post_max_size = 8M //PHP能收到的最大POST值'
memory_limit = 128M //内存上限
max_execution_time = 30 //最大执行时间

为了满足需求,可适量调整配置参数。但遇到超大文件上传,比如视频时,就需要在技术层面解决这一问题。

以下利用 html5 可直接操作二进制文件的新特性,用 PHP + JS 实现将大文件分割上传后再合并的办法,实现大文件上传。

前端代码:

<!doctype html>
<head>
    <title>slide-upload</title>
</head>
<body>

    <input type="file" name="file" id="file">

    <script>
      var fileForm = document.getElementById("file");
      var upload = new Upload();
     
      fileForm.onchange = function(){
        upload.addFileAndSend(this);
      }
     
      function Upload(){
        var xhr = new XMLHttpRequest();
        var form_data = new FormData();
        const LENGTH = 1024 * 1024 * 1;
        var start = 0;
        var end = start + LENGTH;
        var blob;
        var blob_num = 1;
        var is_stop = 0

        //传入文件对象
        this.addFileAndSend = function(that){
          var file = that.files[0];
          blob = cutFile(file);
          sendFile(blob,file);
          blob_num += 1;
        }
        //切割文件
        function cutFile(file){
          var file_blob = file.slice(start,end);
          start = end;
          end = start + LENGTH;
          return file_blob;
        };
        //发送文件
        function sendFile(blob,file){
          var total_blob_num = Math.ceil(file.size / LENGTH);
          form_data.append('file',blob);
          form_data.append('blob_num',blob_num);
          form_data.append('total_blob_num',total_blob_num);
          form_data.append('file_name',file.name);
     
          xhr.open('POST','./slice_upload.php',true);
          xhr.onreadystatechange = function () {
            var progress;
            if(total_blob_num == 1){
              progress = '100%';
            }else{
              progress = Math.min(100,(blob_num/total_blob_num)* 100 ) +'%';
            }
            var t = setTimeout(function(){
              if(start < file.size){
                blob = cutFile(file);
                sendFile(blob,file);
                blob_num += 1;
              }else{
                setTimeout(t);
              }
            },1000);
          }
          xhr.send(form_data);
        }
      }
     
    </script>
</body>
</html>

后台文件上传代码:

<?php
 
//实例化并获取系统变量传参
$upload = new Upload($_FILES['file']['tmp_name'],$_POST['blob_num'],$_POST['total_blob_num'],$_POST['file_name']);
//调用方法,返回结果
$upload->apiReturn();

class Upload{
    private $filepath = './upload'; //上传目录
    private $tmpPath; //PHP文件临时目录
    private $blobNum; //第几个文件块
    private $totalBlobNum; //文件块总数
    private $fileName; //文件名

    public function __construct($tmpPath, $blobNum, $totalBlobNum, $fileName){
        $this->tmpPath = $tmpPath;
        $this->blobNum = $blobNum;
        $this->totalBlobNum = $totalBlobNum;
        $this->fileName = $fileName;
         
        $this->moveFile();
        $this->fileMerge();
    }

    //判断是否是最后一块,如果是则进行文件合成并且删除文件块
    private function fileMerge(){
        if($this->blobNum == $this->totalBlobNum){
            $blob = '';

            for($i=1; $i<= $this->totalBlobNum; $i++){
                $blob .= file_get_contents($this->filepath.'/'. $this->fileName.'__'.$i);
            }
            file_put_contents($this->filepath.'/'. $this->fileName,$blob);
            $this->deleteFileBlob();
        }
    }

    //删除文件块
    private function deleteFileBlob(){
        for($i=1; $i<= $this->totalBlobNum; $i++){
              @unlink($this->filepath.'/'. $this->fileName.'__'.$i);
        }
    }

    //移动文件
    private function moveFile(){
        $this->touchDir();
        $filename = $this->filepath.'/'. $this->fileName.'__'.$this->blobNum;
        move_uploaded_file($this->tmpPath,$filename);
    }

    //API返回数据
    public function apiReturn(){
        if($this->blobNum == $this->totalBlobNum){
            if(file_exists($this->filepath.'/'. $this->fileName)){
              $data['code'] = 2;
              $data['msg'] = 'success';
              $data['file_path'] = 'http://'.$_SERVER['HTTP_HOST'].dirname($_SERVER['DOCUMENT_URI']).str_replace('.','',$this->filepath).'/'. $this->fileName;
            }
        }else{
            if(file_exists($this->filepath.'/'. $this->fileName.'__'.$this->blobNum)){
              $data['code'] = 1;
              $data['msg'] = 'waiting for all';
              $data['file_path'] = '';
            }
        }
        header('Content-type: application/json');
        echo json_encode($data);
    }

    //建立上传文件夹
    private function touchDir(){
        if(!file_exists($this->filepath)){
          return mkdir($this->filepath);
        }
    }
}

 

以上只是实现了简单的上传功能,很多情况下文件传输之前需要加密,或者实现端点传输。

 

 

 

posted @ 2019-01-22 14:15  菜乌  阅读(680)  评论(0编辑  收藏