title: Automatically fetch preview image from given URL in Rails
body: <p>I need help again from the community.</p>
  
  <p>I'm interested to know how to extract a preview image from a given URL in rails.</p>
  
  <p>Basically, it would be a functionality like you have on reddit. When user submits a link (fills in the link field in the _form), a preview image/thumbnail is automatically pulled from a given url. (I would like to save the link of the image as a field in the model, I don't want to save the image itself).</p>
  
  <p>Is there a gem for that or? What's the best way to do it?</p>
  
  <p>Thanks for the help.</p>