功能:支持断点续传的下载,能计算传输率,能控制传输率
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简易使用方法:
$object = new httpdownload();
$object-set_byfile($file)%N#H#%;//服务器文件名,包括路径
$object-filename = $filename;//下载另存为的文件名
$object-download();
3.源文件:
?
class httpdownload {
var $data = null;
var $data_len = 0;
var $data_mod = 0;
var $data_type = 0;
var $data_section = 0; //section download
var $sentSize=0;
var $handler = array('auth' = null);
var $use_resume = true;
var $use_autoexit = false;
var $use_auth = false;
var $filename = null;
var $mime = null;
var $bufsize = 2048;
var $seek_start = 0;
var $seek_end = -1;
var $totalsizeref = 0;
var $bandwidth = 0;
var $speed = 0;
function initialize() {
global $HTTP_SERVER_VARS;
if ($this-use_auth) //use authentication {
if (!$this-_auth()) //no authentication {
header('WWW-Authenticate: Basic realm="Please enter your username and password"');
header('HTTP/1.0 401 Unauthorized');
header('status: 401 Unauthorized');
if ($this-use_autoexit) exit();
return false;
}
}
if ($this-mime == null) $this-mime = "application/octet-stream"; //default mime
if (isset($_SERVER['HTTP_RANGE']) || isset($HTTP_SERVER_VARS['HTTP_RANGE'])) {
if (isset($HTTP_SERVER_VARS['HTTP_RANGE'])) $seek_range = substr($HTTP_SERVER_VARS['HTTP_RANGE'] , strlen('bytes='));
else $seek_range = substr($_SERVER['HTTP_RANGE'] , strlen('bytes='));
$range = explode('-',$seek_range);
if ($range[0] 0) {
$this-seek_start = intval($range[0]);
}
if ($range[1] 0) $this-seek_end = intval($range[1]);
else $this-seek_end = -1;
if (!$this-use_resume) {
$this-seek_start = 0;
//header("HTTP/1.0 404 Bad Request");
//header("Status: 400 Bad Request");
//exit;
//return false;
} else {
$this-data_section = 1;
}
} else {
$this-seek_start = 0;
$this-seek_end = -1;
}
$this-sentSize=0;
return true;
}
function header($size,$seek_start=null,$seek_end=null) {
header('Content-type: ' . $this-mime);
header('Content-Disposition: attachment; filename="' . $this-filename . '"');
header('Last-Modified: ' . date('D, d M Y H:i:s /G/M/T' , $this-data_mod));
if ($this-data_section $this-use_resume) {
header("HTTP/1.0 206 Partial Content");
header("Status: 206 Partial Content");
header('Accept-Ranges: bytes');
header("Content-Range: bytes $seek_start-$seek_end/$size");
header("Content-Length: " . ($seek_end - $seek_start + 1));
} else {
header("Content-Length: $size");
}
}
function download_ex($size) {
if (!$this-initialize()) return false;
ignore_user_abort(true);
//Use seek end here
if ($this-seek_start ($size - 1)) $this-seek_start = 0;
if ($this-seek_end = 0) $this-seek_end = $size - 1;
$this-header($size,$seek,$this-seek_end);
$this-data_mod = time();
return true;
}
function download() {
if (!$this-initialize()) return false;
try {
error_log("begin download/n", 3,"/usr/local/www/apache22/LOGS/apache22_php.err");
$seek = $this-seek_start;
$speed = $this-speed;
$bufsize = $this-bufsize;
$packet = 1;
//do some clean up
@ob_end_clean();
$old_status = ignore_user_abort(true);
@set_time_limit(0);
$this-bandwidth = 0;
$size = $this-data_len;
if ($this-data_type == 0) //download from a file {
$size = filesize($this-data);
if ($seek ($size - 1)) $seek = 0;
if ($this-filename == null) $this-filename = basename($this-data);
$res = fopen($this-data,'rb');
if ($seek) fseek($res , $seek);
if ($this-seek_end $seek) $this-seek_end = $size - 1;
$this-header($size,$seek,$this-seek_end); //always use the last seek
$size = $this-seek_end - $seek + 1;
while (!(connection_aborted() || connection_status() == 1) $size 0) {
if ($size $bufsize) {
echo fread($res , $size);
$this-bandwidth += $size;
$this-sentSize+=$size;
} else {
echo fread($res , $bufsize);
$this-bandwidth += $bufsize;
$this-sentSize+=$bufsize;
}
$size -= $bufsize;
flush();
if ($speed 0 ($this-bandwidth $speed*$packet*1024)) {
sleep(1);
$packet++;
}
}
fclose($res);
}
elseif ($this-data_type == 1) //download from a string
{
if ($seek ($size - 1)) $seek = 0;
if ($this-seek_end $seek) $this-seek_end = $this-data_len - 1;
$this-data = substr($this-data , $seek , $this-seek_end - $seek + 1);
if ($this-filename == null) $this-filename = time();
$size = strlen($this-data);
$this-header($this-data_len,$seek,$this-seek_end);
while (!connection_aborted() $size 0) {
if ($size $bufsize) {
$this-bandwidth += $size;
$this-sentSize+=$size;
} else {
$this-bandwidth += $bufsize;
$this-sentSize+=$bufsize;
}
echo substr($this-data , 0 , $bufsize);
$this-data = substr($this-data , $bufsize);
$size -= $bufsize;
flush();
if ($speed 0 ($this-bandwidth $speed*$packet*1024)) {
sleep(1);
$packet++;
}
}
} else if ($this-data_type == 2) {
//just send a redirect header
header('location: ' . $this-data);
}
if($this-totalsizeref==$this-sentSize )error_log("end download/n", 3,"/usr/local/www/apache22/LOGS/apache22_php.err");
else error_log("download is canceled/n", 3,"/usr/local/www/apache22/LOGS/apache22_php.err");
if ($this-use_autoexit) exit();
//restore old status
ignore_user_abort($old_status);
set_time_limit(ini_get("max_execution_time"));
}
catch(Exception $e) {
error_log("cancel download/n".$e, 3,"/usr/local/www/apache22/LOGS/apache22_php.err");
}
return true;
}
function set_byfile($dir) {
if (is_readable($dir) is_file($dir)) {
$this-data_len = 0;
$this-data = $dir;
$this-data_type = 0;
$this-data_mod = filemtime($dir);
$this-totalsizeref = filesize($dir);
return true;
} else return false;
}
function set_bydata($data) {
if ($data == '') return false;
$this-data = $data;
$this-data_len = strlen($data);
$this-data_type = 1;
$this-data_mod = time();
return true;
}
function set_byurl($data) {
$this-data = $data;
$this-data_len = 0;
$this-data_type = 2;
return true;
}
function set_lastmodtime($time) {
$time = intval($time);
if ($time = 0) $time = time();
$this-data_mod = $time;
}
function _auth() {
if (!isset($_SERVER['PHP_AUTH_USER'])) return false;
if (isset($this-handler['auth']) function_exists($this-handler['auth'])) {
return $this-handler['auth']('auth' , $_SERVER['PHP_AUTH_USER'],$_SERVER['PHP_AUTH_PW']);
} else return true; //you must use a handler
}
}
?
可以通过$_SERVER['HTTP_RANGE']取得用户请求的文件的range来实现。
其实说简单点就是通过这个变量$_SERVER['HTTP_RANGE']取得用户请求的文件的range，然后程序去控制文件的输出。比如第一次请求一个文件的从0到999字节，第二次请求1000到1999字节，以此类推，每次请求1000字节的内容，然后程序通过fseek函数去取得对应的文件位置，然后输出。
网上有很多这样的教程可以去查一查。
现在这个时代文件存储基本分离到了单独的存储服务上面,比如说阿里云的OSS,七牛云的云存储等等.考虑这些第三方服务的话,那么你的大文件上传和断点续传等功能实现只需要去对接服务商提供的API接口即可(好处就是上传服务的压力等因素服务商帮你抗,不好就是你得付钱给服务商),其中方案就是js-sdk只传OSS的方式,稳定性好,只传断点续传和实时浏览上传进度。
如果你是大神,需要自己在服务器实现上述功能,那么要考虑的不仅是实现本身的需求,还得考虑服务器是否能抗得住这样的上传压力(带宽,延时),还有存储空间是否足够等额外的问题.
HTTP协议里, 对断点下载有支持.
断点上传单纯靠PHP 是做不了的.
因为普通的浏览器端没那功能.(上传的时候 还是会整个文件编码发送)
想实现的话 , 客户端需要插件了,
客户端可以使用flex实现. 服务端, PHP可以写个webservice 接受文件.
可以在网上找找. 关键字: "flex php 上传"
大文件上传, 走 http 是比较费劲儿的. 不稳定是关键.
是实现断点续传，就需要把大文件分割成多个小文件，然后单个上传。传完后在合并。
│ merge.PHP –合并文件脚本
│ merge.zip –合并后文件
│ socket.zip –需要分割的文件
│ split.php –分割文件脚本
│
└─split –分割后小文件目录
下面是源码
split.php
?php
$fp = fopen("socket.zip", "rb");
$filesize = 10;
$i = 0;
$no = 1;
while(!feof($fp))
{
$file = fread($fp, $filesize);
$fp2 = fopen("./split/socket.port".sprintf("%04d",$no).".".$i."-".($i+$filesize).".tmp", "wb");fwrite($fp2, $file, $filesize);
fclose($fp2);
$i+=$filesize+1;
$no++;
}
fclose($fp);
merge.php
?php
$filelist = glob('./split/*socket*.tmp');$filesize = 10;
//print_r($filelist);
$mergeFileName = 'merg.zip';
unlink($mergeFileName);
$fp2 = fopen($mergeFileName,"w+");
foreach($filelist as $k = $v)
{
$fp = fopen($v, "rb");
$content = fread($fp, $filesize);
fwrite($fp2, $content, $filesize);
unset($content);
fclose($fp);
echo $k,"\n";
}
fclose($fp2);
