Gist for some marshalling and effect on the size of the resulting string

JsonSizePoc.scala

import java.io.ByteArrayOutputStream
import java.time.{Instant, ZonedDateTime}
import java.util.zip.GZIPOutputStream

import spray.json._

import scala.util.Random

case class SensorRecord(timestamp: ZonedDateTime, sensor1: Int, sensor2: Int, sensor3: Int, sensor4: Int, sensor5: Int, sensor6: Int, sensor7: Int, sensor8: Int, sensor9: Int, sensor10: Int, sensor11: Int)

case class DataRecord(exerciseId: String, gloveId: String, data: List[SensorRecord])


object SensorDataProtocol extends DefaultJsonProtocol {
  
  implicit object SensorRecordJsonFormat extends RootJsonFormat[SensorRecord] {
    def write(r: SensorRecord) =
      JsArray(JsNumber(r.timestamp.toInstant.toEpochMilli), JsNumber(r.sensor1), JsNumber(r.sensor2), JsNumber(r.sensor3), JsNumber(r.sensor4), JsNumber(r.sensor5), JsNumber(r.sensor6), JsNumber(r.sensor7), JsNumber(r.sensor8), JsNumber(r.sensor9), JsNumber(r.sensor10), JsNumber(r.sensor11))

    def read(value: JsValue) = value match {
      case JsArray(Vector(JsNumber(timestamp), JsNumber(sensor1), JsNumber(sensor2), JsNumber(sensor3), JsNumber(sensor4), JsNumber(sensor5), JsNumber(sensor6), JsNumber(sensor7), JsNumber(sensor8), JsNumber(sensor9), JsNumber(sensor10), JsNumber(sensor11))) =>
        new SensorRecord(ZonedDateTime.from(Instant.ofEpochMilli(timestamp.toLong)), sensor1.toInt, sensor2.toInt, sensor3.toInt, sensor4.toInt, sensor5.toInt, sensor6.toInt, sensor7.toInt, sensor8.toInt, sensor9.toInt, sensor10.toInt, sensor11.toInt)
      case _ => deserializationError("Sensor Data record expected")
    }
  }

  implicit val dataRecordFormat = jsonFormat3(DataRecord)
}

object JsonSizePoc {
  val r = Random
  r.setSeed(12345)

  def nextValue: Int = r.nextInt(1023)

  def newSensorRecord:SensorRecord = {
    SensorRecord(ZonedDateTime.now(), nextValue, nextValue, nextValue, nextValue, nextValue, nextValue, nextValue, nextValue, nextValue, nextValue, nextValue)
  }

  def printSize(data: String) = {
    println(s"${data.length} bytes")
    println(s"${data.length/1024}Kb")
    println(s"${data.length/1024/1024}Mb")
  }


  def main(args: Array[String]) {
    import SensorDataProtocol._

    val tmp = DataRecord("exercise_1", "glove_1", List(newSensorRecord))
    println(tmp.toJson)


    val cnt = 15 * 60 * 100

    println(cnt)
    val records = List.fill(cnt)(newSensorRecord)

    val dataRecord = DataRecord("id1", "glove1", records)
    println(" Raw")
    printSize(dataRecord.toJson.toString)

    val y = new ByteArrayOutputStream()
    val x = new GZIPOutputStream(y)
    x.write(dataRecord.toJson.toString().getBytes)
    x.flush()
    println("Zipped")
    printSize(y.toString)
  }
}