title: how to represent nested JSON object in a case class using Json4s?
body: <p>Given an example JSON object with a nested object who's properties are unkown:</p>
  
  <pre><code>      { "Key":"01234",
            "eventProperties":{
               "unknownProperty1":"value",
               "unknownProperty2":"value",
               "unknownProperty3":"value"
            },
         }
  </code></pre>
  
  <p>I have tried to use json4s' extract function with the following case class (In Scala):</p>
  
  <pre><code>case class nestedClass(Key:String, eventProperties:Map[(String,Any)])
  </code></pre>
  
  <p>Which results in the following error:</p>
  
  <pre><code>org.json4s.package$MappingException: Can't find constructor for nestedClass
  </code></pre>
  
  <p>Is it possible to do this without defining every possible property of eventProperties?</p>
  
  <p><strong>Update:</strong> there was a bug in json4s 3.2.10 causing this issue - updating to 3.2.11 and extracting to Map[String,Any] works fine.</p>