Using PHP to limit download speed

[chipgraphics]

:confused::confused:

I have been on the quest to find a php script that can serve files for downloads and limit the speed at which the file is transfered to the user. I want a faster download speed for registered members and a slower speed for guests.

The only other thing I can think of is using the header() function to force a download for the requested file type and stream the file to the user's browser. Then using sleep() or usleep() on a loop until the download completes.

Anyone have any suggestions or ideas?

~Chipgraphics

[Niheel]

Here is a snippet i found on php.net.

[font=Courier New]<?php
 
$file = "test.mp3"; [/font][font=Courier New]// file to be send to the client
$speed = 8.5; [/font][font=Courier New]// 8,5 kb/s download rate limit
 
if(file_exists($file) && is_file($file[/font][font=Courier New])) {
 
   header("Cache-control: private"[/font][font=Courier New]);
   header("Content-Type: application/octet-stream"[/font][font=Courier New]); 
   header("Content-Length: ".filesize($file[/font][font=Courier New]));
   header("Content-Disposition: filename=$file" . "%20"[/font][font=Courier New]); 
 
   flush[/font][font=Courier New]();
 
   $fd = fopen($file, "r"[/font][font=Courier New]);
   while(!feof($fd[/font][font=Courier New])) {
         echo fread($fd, round($speed*1024[/font][font=Courier New]));
       flush[/font][font=Courier New]();
       sleep(1[/font][font=Courier New]);
   }
   fclose ($fd[/font][font=Courier New]);
 
}
?> [/font]
 

Link to page and exact code.

[chipgraphics]

With the constant change of protocols and programming yada yada. I read over what you had suggested and combined a couple of the concepts into one package deal. And it worked on the first try ! :D So, thank you for pointing me in the right direction ! I'll list my source code below.

Here's a function to use PHP to control download bandwith speed:
All original code I borrowed from PHP's online documentation found HERE.

<?php
function send_file($file, $speed = 100) {
 
    //First, see if the file exists  
    if (!is_file($file)) {
        die("<b>404 File not found!</b>");
    }  
    //Gather relevent info about file
    $filename = basename($file);
    $file_extension = strtolower(substr(strrchr($filename,"."),1));
    // This will set the Content-Type to the appropriate setting for the file
    switch( $file_extension ) {
        case "exe":
            $ctype="application/octet-stream";
            break;
        case "zip":
            $ctype="application/zip";
            break;
        case "mp3":
            $ctype="audio/mpeg";
            break;
        case "mpg":
            $ctype="video/mpeg";
            break;
        case "avi":
            $ctype="video/x-msvideo";
            break;
 
        //  The following are for extensions that shouldn't be downloaded
        // (sensitive stuff, like php files)
        case "php":
        case "htm":
        case "html":
        case "txt":
            die("<b>Cannot be used for ". $file_extension ." files!</b>");
            break;
        default:
            $ctype="application/force-download";
    }
 
    //  Begin writing headers
    header("Cache-Control:");
    header("Cache-Control: public");
    header("Content-Type: $ctype");
 
    $filespaces = str_replace("_", " ", $filename);
    // if your filename contains underscores, replace them with spaces
 
    $header='Content-Disposition: attachment; filename='.$filespaces;
    header($header);
    header("Accept-Ranges: bytes");
 
    $size = filesize($file);  
    //  check if http_range is sent by browser (or download manager)  
    if(isset($_SERVER['HTTP_RANGE'])) {
        // if yes, download missing part     
 
        $seek_range = substr($_SERVER['HTTP_RANGE'] , 6);
        $range = explode( '-', $seek_range);
        if($range[0] > 0) { $seek_start = intval($range[0]); }
        if($range[1] > 0) { $seek_end  =  intval($range[1]); }
 
        header("HTTP/1.1 206 Partial Content");
        header("Content-Length: " . ($seek_end - $seek_start + 1));
        header("Content-Range: bytes $seek_start-$seek_end/$size");
    } else {
        header("Content-Range: bytes 0-$seek_end/$size");
        header("Content-Length: $size");
    }  
    //open the file
    $fp = fopen("$file","rb");
 
    //seek to start of missing part  
    fseek($fp,$seek_start);
 
    //start buffered download
    while(!feof($fp)) {      
        //reset time limit for big files
        set_time_limit(0);      
        print(fread($fp,1024*$speed));
        flush();
        sleep(1);
    }
    fclose($fp);
    exit;
}
?>

I hope that helps someone out too. Thanks again for pointing me in the right direction !!


~Chipgraphics

[Niheel]

Hey, congrats on getting the results you were looking for.

Thanks for posting the code for people to learn from, that's what this forum is all about.


~KUB

[Flegma]

I used that script from php.net but i have a problem. When i click on download it starts download, but on ~600kB it stops and dont download....
can abybody explain me thit??

[Niheel]

Download issues from their server. Maybe wait for a few hrs and try again.

[Flegma]

Download issues from their server. Maybe wait for a few hrs and try again.

it is localhost.....
can it be some option of apache ???
in my webhosting i tried to download 20 MB and it was OK....

[pezhvak]

@Flegma
it's because php stops your script (your script will timeout).. to avoid it, copy following code in the top of your script:

set_time_limit(99999999);

[s1dest3pnate]

I'm pretty new to PHP. Where in this file would I include the name of the file that I want the user to download or is there a different way to set what file to use this script for? Thanks in advance!

[Dormilich]

the file name is the function’s first parameter.

[s1dest3pnate]

My fault. I meant in chipgraphics code.

I would assume I would input the filename somewhere in this line:

$filename = basename($file);

If not, where?

Thanks in advance.

[Dormilich]

function send_file($file, $speed = 100) {

as can be deduced from line 5 to 9.

[xphile]

This code works on my station only if I comment sleep statement! Otherwise browser waiting for file but download doesn't starts. Why?
System: Debian squeeze 2.6.31.6 / Apache 2.2.14-3 / PHP 5.2.1