transfer a file bigger than 500mb - php

Question

i created a file with php that can stream a file in a server but the only problem i am having is the resume and i can download only with 1 parallel using IDM i have been searching for a week without finding any thing that helps this is my code
<?php
$file = 'http://www.affymetrix.com/support/downloads/demo_data/Demo_Data_Barley_MAS5.zip';
function get_size($url){
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_HEADER, true);
curl_setopt($ch, CURLOPT_NOBODY, true);
curl_exec($ch);
$size = curl_getinfo($ch, CURLINFO_CONTENT_LENGTH_DOWNLOAD);
return intval($size);
}
$fp = #fopen($file, 'rb');
$size = get_size($file); // File size
$length = $size; // Content length
$start = 0; // Start byte
$end = $size - 1; // End byte
header('Content-Type: application/octet-stream');
header("Content-Disposition: attachment; filename=Demo_Data_Barley_MAS5.zip");
//header('Content-type: video/mp4');
header("Accept-Ranges: 0-$length");
if (isset($_SERVER['HTTP_RANGE'])) {
$c_start = $start;
$c_end = $end;
list(, $range) = explode('=', $_SERVER['HTTP_RANGE'], 2);
if (strpos($range, ',') !== false) {
header('HTTP/1.1 416 Requested Range Not Satisfiable');
header("Content-Range: bytes $start-$end/$size");
exit;
}
if ($range == '-') {
$c_start = $size - substr($range, 1);
}else{
$range = explode('-', $range);
$c_start = $range[0];
$c_end = (isset($range[1]) && is_numeric($range[1])) ? $range[1] : $size;
}
$c_end = ($c_end > $end) ? $end : $c_end;
if ($c_start > $c_end || $c_start > $size - 1 || $c_end >= $size) {
header('HTTP/1.1 416 Requested Range Not Satisfiable');
header("Content-Range: bytes $start-$end/$size");
exit;
}
$start = $c_start;
$end = $c_end;
$length = $end - $start + 1;
fseek($fp, $start);
header('HTTP/1.1 206 Partial Content');
}
header("Content-Range: bytes $start-$end/$size");
header("Content-Length: ".$length);
$buffer = 1024 * 8;
while(!feof($fp) && ($p = ftell($fp)) <= $end) {
if ($p + $buffer > $end) {
$buffer = $end - $p + 1;
}
set_time_limit(0);
echo fread($fp, $buffer);
flush();
}
fclose($fp);
exit();
?>
i am really thank full if some one can help me out here

Answer 1

Use following gist source code for this: https://gist.github.com/kijin/9735300
(im sorry for that linked gist source code annotated by Korean)
Translation of header:
supports:
1. do not break filename when use UTF-8 filename.
2. remove or replace if included unknown character by OS.
3. Add Cache-Control, Expires header when you want to use cache.
4. Fix the download error when use cache and IE <= 8.
5. Support resume download (automatically detect Range header, auto generate Accept-Ranges header)
6. Fix memory leak when download large file.
7. Can limit download speed.
How to use: send_attachment('filename that provide to client', 'file path', [period of the caching], [speed limit]);
this example is download 'foo.jpg' from server to client named 'photo.jpg'
send_attachment('photo.jpg', '/srv/www/files/uploads/foo.jpg')
Return: true when successfully sent else false.
Warning: 1. please execute 'exit' when end the transfer.
2. don't ensure that php version is very low(< 5.1) or not UTF-8 environment.
3. speed limitation is very dangerous when you using FastCGI/FPM. recommend to use web server's speed limitation.
4. some android versions does not support UTF-8 encoding.
Note: I recommend to use X-Accel-Redirect(nginx) or X-Sendfile(apache) header when transfer a big file. If you transfer big file on the php interpreter, the php have many load and it works very inefficiently.
Add: here is the code that you want to do - https://gist.github.com/ssut/a3d97c7a35e5458687ed
(note: I'm very poor in english, some translation is imprecise)
I tested this code on nginx + php 5.5(fpm) environment and this is test code: send_attachment('ubuntu.iso', 'http://ftp.daum.net/ubuntu-releases/trusty/ubuntu-14.04-server-amd64.iso');
IDM screenshot: