Download codes?

January 26, 2011 2:58 PM

Where can I find some sort of free download-code script or software for my website?

I'd like to add to my site a place where users can enter a download code they have purchased and then download a corresponding file. Each person gets a unique download code that can only be used, say, 3 times or so.

Are there any sort of pre-made systems I can install on my site, or other ways of implementing something like this? Preferably something customizable.

I thought of trying to code a simple way of doing this myself but I'm worried about security issues (people without codes just going straight to the download link, for example).

posted by god particle to Computers & Internet (3 answers total)

A lot of companies will help you with this; see here. e-Junkie being a common example...
posted by circular at 3:06 PM on January 26, 2011

I can think of simple ways to do this, but I don't know of any pre-made solutions.

For example:
1) store the files in a location that they are not publicly accessible (i.e., outside DocumentRoot)
2) in your database that tracks downloads, you need columns for CODE, FILE, and DOWNLOAD_COUNT
3) You have a server-side script that does effectively this:

$rows = select * from downloads where CODE = $code

if (($rows has exactly one entry) and ($rows[0][DOWNLOAD_COUNT] <> {
print "Content-Length:"
print length($rows[0][FILE])
print "\r\n"
print "Content-Disposition: attachment; filename="
print $rows[0][FILE].replace(/^.*\///)
print "\r\n"

cat $rows[0][FILE]

update downloads set DOWNLOAD_COUNT = DOWNLOAD_COUNT + 1 where CODE = $code;

}
else
{
return 403;
}

Sorry, my pseudo-code is a mash mash of perl, SQL, javascript and shell, but that's really about all the logic you need to do this.
posted by tylerkaraszewski at 3:16 PM on January 26, 2011 [1 favorite]

If you're ok with using a third party solution, I know someone who's used Payloadz and seems happy with it.
posted by korej at 3:34 PM on January 26, 2011