Securing downloads

Python

Im working on something now and it lets users buy digital products which after payment they are given a link to download - which works fine...

But how can I protect the downloads?


Basically I want do have something like download.php?file=something

This when clicked then starts the download but without giving them the location of the file on the server. I also dont want the file extension to be within the url...

So basically how can I initiate a download in a PHP file

Thanks

CannonBallGuy

Cant "download.php" have lists of ifs...
like:
IF (file==something){then somehow download "something.extension"}
elseIF (file==article){then somehow download "article0193.whatever"}
elseIF (file==0800){then somehow download "number0800.haha"}

and so on...

Python

well it could... but i dont wanna sit there and type in an extra if statement each time i add a new download...

CannonBallGuy

then can't you do something like:

download "$file",".php"

so that if its: download.php?file=something
it downloads "something.php"...?