how to limit file download size?

Hi, I'm writing a ruby on rails application that allows the user to
submit a link of a file which my app will then download.
Right now my app blindly downloads the file (which is 1-2mb on
I'm worried about pranksters who would intentionally submit links to
30gb files.
Is there a way to set the maximum size of a file that I'm downloading?

One possible solution is to parse the content-length field of the file
header. But the server need not send this field along with the file.

I just want my application to stop downloading when the file gets to a
certain size (say 2mb) and alert the user that the file they submitted
is too big.



This is a job of the web server. For apache look up the
LimitRequestBody configuration directive - it will allow you to
specify the maximum allowed Content-Length for requests to your