title: ElasticSearch:filtering documents based on field length?
body: <p>Is there a way to filter ElasticSearch documents based on the length of a specific field?</p>
  
  <p>For instance, I have a bunch of documents with the field "body", and I only want to return results where the number of characters in body is > 1000. Is there a way to do this in ES without having to add an extra column with the length in the index?</p>