title: EvaluateJsonPath unable to return a scalar
body: <p>I'm trying to extract a value from JSON to a <strong>flowfile-attribute</strong>. When I run the EvaluateJsonPath processor I get an error stating </p>
  
  <p><code>"Unable to get a scalar value for expression $..fields.storyBoard.stringValue</code>. </p>
  
  <p><strong>Input JSON looks like this:</strong></p>
  
  <pre><code>{
    "name" : "projects/fakedims-0000/databases/(default)/documents/device/0000",
    "fields" : {
      "reportKey" : {
        "stringValue" : "abc123"
      },
      "dateOccured" : {
        "timestampValue" : "2018-10-14T04:00:00Z"
      },
      "storyBoard" : {
        "stringValue" : "https://path/to/media"
      },
      "new" : {
        "integerValue" : "25"
      },
      "name" : {
        "stringValue" : "device one"
      },
      "location" : {
        "geoPointValue" : {
          "latitude" : -78.413751,
          "longitude" : 38.156487
        }
      }
    },
    "createTime" : "2018-10-19T00:02:26.209335Z",
    "updateTime" : "2018-10-19T22:22:24.382136Z"
  }
  </code></pre>
  
  <p>The JSONPath expression is <code>$..fields.storyBoard.stringValue</code> </p>
  
  <p>What I think is happening is that the processor is returning <code>["https://path/to/media"]</code> rather than just the string. </p>
  
  <p>This is what I get if a evaluate to flowfile-content rather than an attribute. Why? What can I do to fix it?</p>