title: Caching signed S3 URI's with paperclip and rails
body: <p>I'm generating expiring signed URI's with paperclip on S3. However on every request I generate a new URI which is not ideal and it forces the browser to download a new set of images from S3  on every page refresh.</p>
  
  <p>What I'd like to do is cache the generated URI's for a little less time than they expire on S3. Has anybody done anything like this before and can suggest a solution. </p>
  
  <p>I'm deploying on heroku if that suggests a solution ( or not )</p>