title: Verifying permissions on S3 object in Ruby
body: <p>I'm using <a href="https://github.com/aws/aws-sdk-ruby" rel="nofollow">aws-sdk for Ruby</a> to manage objects on S3. I'm able grant public read permissions by setting</p>
  
  <pre><code>object.acl = :public_read
  </code></pre>
  
  <p>Is there a way to determine if there is already public read permission granted to the object before doing that?</p>