Resumable downloads when using PHP to send the file?

Question

We are using a PHP scripting for tunnelling file downloads, since we don\'t want to expose the absolute path of downloadable file:

header(\"Content-Type: $ct         


        

Answer 1

Yes, you can use the Range header for that. You need to give 3 more headers to the client for a full download:

header ("Accept-Ranges: bytes");
header ("Content-Length: " . $fileSize);
header ("Content-Range: bytes 0-" . $fileSize - 1 . "/" . $fileSize . ";");

Than for an interrupted download you need to check the Range request header by:

$headers = getAllHeaders ();
$range = substr ($headers['Range'], '6');

And in this case don't forget to serve the content with 206 status code:

header ("HTTP/1.1 206 Partial content");
header ("Accept-Ranges: bytes");
header ("Content-Length: " . $remaining_length);
header ("Content-Range: bytes " . $start . "-" . $to . "/" . $fileSize . ";");

You'll get the $start and $to variables from the request header, and use fseek() to seek to the correct position in the file.