title: JOLT Spec for DataFrame input (NiFi JoltTransformJson)
body: <p>Could you please help me writing JOLT spec for the following?</p>
  <p>Input JSON:</p>
  <pre class="lang-json prettyprint-override"><code>{
    &quot;a&quot;: &quot;1&quot;,
    &quot;b&quot;: &quot;2&quot;,
    &quot;c&quot;: &quot;3&quot;,
    &quot;d&quot;: &quot;4&quot;
  }
  </code></pre>
  <p>I need to get output:</p>
  <pre class="lang-json prettyprint-override"><code>{
    &quot;columns&quot;: [&quot;a&quot;,&quot;b&quot;,&quot;c&quot;,&quot;d&quot;],
    &quot;data&quot;: [[1,2,3,4]]
  }
  </code></pre>