Determine modification time of remote (http) file

Rails
1

Is there way to determine the last modification time of a file via HTTP?
Specifically, I’d like to not download or parse a very large RSS file
(300+
items) if it hasn’t changed.

TIA,
Jeffrey

2

Hi,

there is 304 HTTP response code that says “not modified”. However,
you’ll not be able to use it unless RSS file provider is actually
serving this response to you. I know apache for static files does just
that, but if on the other end is application that doesn’t provide
caching for RSS feeds (sic!) you’re toast.

H.

3

Quoting Hubert Łępicki [email protected]:

Hi,

there is 304 HTTP response code that says “not modified”. However,
you’ll not be able to use it unless RSS file provider is actually
serving this response to you. I know apache for static files does just
that, but if on the other end is application that doesn’t provide
caching for RSS feeds (sic!) you’re toast.

Thank you. I tried using the -N flag of wget on the largest feed and it
doesn’t appear to support the last_modified meta tag (or whatever it’s
called,
I’m still learning). I may eventually implement the feature, but it
won’t
help with the immediate problem.

Thanks,
Jeffrey