title: How can I remove field which are nil in CSV file
body: <p>My CSV file contains fields which are nil like that : </p>
  
  <pre><code>{ "message" =&gt; [
  [0] "m_FRA-LIENSs-R2012-1;\r"
  ],
                 "@version" =&gt; "1",
               "@timestamp" =&gt; "2015-05-24T13:51:14.735Z",
                     "host" =&gt; "debian",
             "SEXTANT_UUID" =&gt; "m_FRA-LIENSs-R2012-1",
  "SEXTANT_ALTERNATE_TITLE" =&gt; nil
  </code></pre>
  
  <p>}</p>
  
  <pre><code>How can I remove all : messages and fields 
  </code></pre>
  
  <p>Here is my CSV file </p>
  
  <pre><code>SEXTANT_UUID|SEXTANT_ALTERNATE_TITLE   
  a1afd680-543c | ZONE_ENJEU  
  4b80d9ad-e59d | ZICO   
  800d640f-1f82 |          
  </code></pre>
  
  <p>I want to delete the last line, I used filter ruby, but it doesn't work! It remove just the field not the entire message.</p>