title: Replicate facebook open graph, how to get OG values on URL links
body: <p>I'm wondering how facebook extracts the open graph values from a link. </p>
  
  <pre><code>&lt;meta property="og:type" content="website"&gt;
  &lt;meta property="og:url" content="http://sample.com"&gt;
  &lt;meta property="og:title" content="sample title"&gt;
  &lt;meta property="og:description" content="sample description"&gt;
  </code></pre>
  
  <p>Cross-domain is a big issue here I think if the link is just on my domain I can do it with AJAX. I also have this idea via <code>&lt;iframe&gt;</code> like this:</p>
  
  <pre><code>$('iframe').contents().find('meta[property=og:title]').attr("content");
  //will output me: 'sample title'
  </code></pre>
  
  <p>But I've also need to put in consideration the loading/rendering time of an iframe so it's not the best option. Any help would be appreciated, thanks.</p>
  
  <p>PS. Can also someone tell me the supported og:type on facebook, it seems this link is broken: <a href="https://developers.facebook.com/docs/reference/opengraph/object-type" rel="nofollow">https://developers.facebook.com/docs/reference/opengraph/object-type</a>
  ; website, blog, article ...?</p>