Letting users download w/o showing the full path to the file

[john010117]

I have a quick question.

 

I don't want my users to know the full path to a file that they're downloading. I instead want to display them as "download.php?file=whatever.zip", and let users download it when they click that link. How would I go about doing that? I know a database is involved (to store the full path to a file), but how would I let them download it when they visit that link?

[redbullmarky]

not as tricky as it can seem. all it generally involves is download.php retrieving the file info, sending the necessary headers and presenting the file just like any other type. i'm a bit rusty with headers and things, but something like:

 

<?php
$upload_dir = $_SERVER['DOCUMENT_ROOT'] . '/uploads';
$filename = $upload_dir . '/myfile.zip';

// send the headers
header("Content-Disposition: attachment; filename=\"".basename($filename)."\"");
header("Content-Transfer-Encoding: binary");
header("Content-Length: ".filesize($filename));

// read the file contents to the output buffer
readfile($filename);
exit;
?>

 

will do the trick. in this example i've assumed that you keep your files in www.yoursite.com/uploads although i wouldnt recommend it, to prevent direct linking to the files themselves. the good thing about scripts like this is they can serve a file from wherever - ie, not necessarily within your web root:

 

- httpdocs/htdocs

  - index.php

  - download.php

  - css

  ...etc...

- uploads

  ... uploaded files here. CANNOT be accessed directly from browser - only the download script.

 

in the above case, you'd simply change the $upload_dir to suit, such as /var/www/uploads or wherever you keep the directory.

 

good luck

[johnrcornell]

The same could be accomplished using mod_rewrite. It's an Apache module that basically takes a requested URL, applies a regex pattern to it and transforms it server side into what it needs to be. So you could have:

 

http://www.mysite.com/scripts/download.php?file=/dl/apps/photoshop.exe

 

turn into:

 

http://www.mysite.com/downloads/photoshop

 

cool stuff eh

[john010117]

Right. Man, I learn something new everyday (in this case, readfile() ). Thanks to both of you. I'll post again if I have any questions.

[gabeg]

The same could be accomplished using mod_rewrite. It's an Apache module that basically takes a requested URL, applies a regex pattern to it and transforms it server side into what it needs to be. So you could have:

 

http://www.mysite.com/scripts/download.php?file=/dl/apps/photoshop.exe

 

turn into:

 

http://www.mysite.com/downloads/photoshop

 

cool stuff eh

 

Won't this become a problem if you have a lot of files? You would have to edit your htaccess file for every file.

[roopurt18]

No.

 

RewriteRule downloads/.* /path/to/script/downloads.php?file=$1

[gabeg]

No.

 

RewriteRule downloads/.* /path/to/script/downloads.php?file=$1

 

good point, I wasn't thinking, thanks!!

[Daniel0]

You shouldn't get the file from a GET parameter. That way people could download all sorts of files like configuration files containing passwords and such.

[roopurt18]

As long as download.php performs checking to determine if the user has access to download the file they've requested, there's no harm in using a GET parameter.

 

Messy, but perfectly valid.