title: Unable to form the JOLT schema to transform JSON in NiFi
body: <p>I am trying to use the jolt JSON to JSON transformation in Apache NiFi. I want to transform one JSON into another format.</p>
  
  <p>Here is my original JSON:</p>
  
  <pre><code>{
    "total_rows": 5884,
    "offset": 0,
    "rows": [
      {
        "id": "03888c0ab40c32451a018be6b409eba3",
        "key": "03888c0ab40c32451a018be6b409eba3",
        "value": {
          "rev": "1-d5cc089dd8682422962ccab4f24bd21b"
        },
        "doc": {
          "_id": "03888c0ab40c32451a018be6b409eba3",
          "_rev": "1-d5cc089dd8682422962ccab4f24bd21b",
          "topic": "iot-2/type/home-iot/id/1234/evt/temp/fmt/json",
          "payload": {
            "temperature": 36
          },
          "deviceId": "1234",
          "deviceType": "home-iot",
          "eventType": "temp",
          "format": "json"
        }
      },
      {
        "id": "03888c0ab40c32451a018be6b409f163",
        "key": "03888c0ab40c32451a018be6b409f163",
        "value": {
          "rev": "1-dee82cbb1b5ffa8a5e974135eb6340c5"
        },
        "doc": {
          "_id": "03888c0ab40c32451a018be6b409f163",
          "_rev": "1-dee82cbb1b5ffa8a5e974135eb6340c5",
          "topic": "iot-2/type/home-iot/id/1234/evt/temp/fmt/json",
          "payload": {
            "temperature": 22
          },
          "deviceId": "1234",
          "deviceType": "home-iot",
          "eventType": "temp",
          "format": "json"
        }
      }
    ]
  }
  </code></pre>
  
  <p>I want this to be transformed in the following JSON:</p>
  
  <pre><code>[
     {
        "temperature":36,
        "deviceId":"1234",
        "deviceType":"home-iot",
        "eventType":"temp"
     },
     {
        "temperature":22,
        "deviceId":"1234",
        "deviceType":"home-iot",
        "eventType":"temp"
     }
  ]
  </code></pre>
  
  <p>This is what my spec looks like:</p>
  
  <pre><code>[
    {
      "operation": "shift",
      "spec": {
        "rows": {
          "*": {
            "doc": {
              "deviceId": "[&amp;1].deviceId",
              "deviceType": "[&amp;1].deviceType",
              "eventType": "[&amp;1].eventType",
              "payload": {
                "*": "[&amp;1]"
              }
            }
          }
        }
      }
    }
  ]
  </code></pre>
  
  <p>I keep getting a null response. I am new to this and the documentation is not very easy to comprehend. Can somebody please help?</p>