{
  "train_station": {
    "properties": {
      "timestamp": {
        "type": "date",
        "format": "yyyy-MM-dd'T'HH:mm:ss.SSSZ"
      },
      "resourceName": {
        "type": "keyword"
      },
      "dataValue": {
        "type": "double"
      }
    }
  }
}