title: Full url for an image-path in Rails 3
body: <p>I have an Image, which contains carrierwave uploads: </p>
  
  <pre><code>Image.find(:first).image.url #=&gt; "/uploads/image/4d90/display_foo.jpg"
  </code></pre>
  
  <p>In my view, I want to find the absolute url for this. Appending the <a href="https://stackoverflow.com/questions/1939942/generate-full-url-to-javascript-in-rails-similar-to-javascript-path-but-url">root_url</a> results in a double <code>/</code>.</p>
  
  <pre><code>root_url + image.url #=&gt; http://localhost:3000//uploads/image/4d90/display_foo.jpg
  </code></pre>
  
  <p>I cannot use <a href="https://stackoverflow.com/questions/3489838/full-url-with-url-for-in-rails">url_for</a> (that I know of), because that <em>either</em> allows passing a path, <em>or</em> a list of options to identify the resource and the <code>:only_path</code> option. Since I do't have a resource that can be identified trough "controller"+"action" I cannot use the <code>:only_path</code> option. </p>
  
  <pre><code>url_for(image.url, :only_path =&gt; true) #=&gt; wrong amount of parameters, 2 for 1
  </code></pre>
  
  <p>What would be the cleanest and best way to create a path into a full url in Rails3?</p>