title: Making timestamp field available in kibana via elasticsearch with kafka
body: <p>How do I allow kibana to use my timestamp field as @timestamp when adding data via Kafka elasticsearch connector?</p>
  
  <p>I am defining my avro schema like so</p>
  
  <pre><code>    public static String userSchema =  "{\"type\":\"record\"," +
                                           "\"name\":\"myrecord\"," +
                                           "\"fields\":[" +
                                           "{\"name\":\"wSrcTime\",\"type\":[\"string\", \"null\"],\"default\":\"null\"}," +
                                           "{\"name\":\"wTradePrice\",\"type\":[\"null\",\"float\"],\"default\":null}," +
                                           "{\"name\":\"timestamp\",\"type\":{\"type\":\"long\",\"logicalType\":\"timestamp-millis\"}}" +
                                           "]}";
  </code></pre>
  
  <p>and use this to populate the field</p>
  
  <pre><code>avroRecord.put("timestamp", System.currentTimeMillis());
  </code></pre>
  
  <p>I see the data kafka-avro-console-consumer as follows:</p>
  
  <pre><code>{"wSrcTime":{"string":"2019-08-01 15:20:40.127"},"wTradePrice":null,"timestamp":1564672840137}
  {"wSrcTime":{"string":"2019-08-01 15:20:41.062"},"wTradePrice":null,"timestamp":1564672841072}
  {"wSrcTime":{"string":"2019-08-01 15:20:41.062"},"wTradePrice":null,"timestamp":1564672841073}
  {"wSrcTime":{"string":"2019-08-01 15:20:41.064"},"wTradePrice":null,"timestamp":1564672841075}
  {"wSrcTime":{"string":"2019-08-01 15:20:41.065"},"wTradePrice":null,"timestamp":1564672841076}
  {"wSrcTime":{"string":"2019-08-01 15:20:41.410"},"wTradePrice":null,"timestamp":1564672841420}
  </code></pre>
  
  <p>And see the data added to kibana index as </p>
  
  <pre><code>timestamp: number
  wTradePrice: number
  wSrcTime: string
  </code></pre>
  
  <p>Is there a recommended way of making timestamp @timestamp so I can use it on an axis?
  Thank you</p>