title: Using mule expression to point to elements in JsonData Object
body: <p>I have an inbound payload in JSON format. I'm converting it using the "JSON to Object" converter, and then passing on the data to a component (as a JsonData object.) My component then returns the same JsonData object with modifications. I'm trying to use the Amazon S3 component as the next step in my flow, and trying to tie the bucket name and other values to elements accessible in the JsonData object.
  Here is the expression for the bucket name for instance:</p>
  
  <pre><code>#[json: TopKey/BucketName]
  </code></pre>
  
  <p>From experience this has worked with JSON.</p>
  
  <p>However when I run this, here is what I get:</p>
  
  <p>Message               : Failed to invoke getObjectContent. Message payload is of type: JsonData
  Code                  : MULE_ERROR-29999</p>
  
  <ol>
  <li>Failed to invoke getObjectContent. Message payload is of type: JsonData (org.mule.api.MessagingException)
  org.mule.module.s3.processors.GetObjectContentMessageProcessor:177 (<a href="http://www.mulesoft.org/docs/site/current3/apidocs/org/mule/api/MessagingException.html" rel="nofollow">http://www.mulesoft.org/docs/site/current3/apidocs/org/mule/api/MessagingException.html</a>)</li>
  </ol>
  
  <p>Is there a way I can use my JsonData object and pull information from it, or do I have to convert it back to something else before passing it on to the Amazon S3 component?</p>
  
  <p>Thanks,</p>