A simple test to know if there is a performence pb in circe

CirceCheck.scala

package perf
import play.api.libs.json.Json
import io.circe._, io.circe.generic.auto._, io.circe.jawn._, io.circe.syntax._
import io.circe._
import io.circe.generic.auto._
import io.circe.jawn._
import io.circe.syntax._

//use 0.1.1 circe
//use play 2.3.8


case class IP(ip : Option[String], remote_ip : String)

object IP {
  implicit val formatOrder = play.api.libs.json.Json.format[IP] 
}

object Test {
	  
  def time[T](f:  => T, message:  String = "" ):  T  = {
    val a = System.nanoTime()
    val r = f
    val b = System.nanoTime()
    println(message + " elapsed time :"+  (b - a) / 1000000.0 + "ms" + Console.RESET )
    r
  }

  def run = {
  	import Console._
	  val v = IP(Some("1"),"2")
	  val v2 = IP(Some("3"),"4")


	  time(v.asJson,BLUE + "circe") //look like init something it's very long 200ms
	  time(v.asJson,BLUE + "circe") // avg 6-8 ms on my computer
	  time(v.asJson,BLUE + "circe") // idem
	  time(v.asJson.toString,BLUE + "circe try to avoid lazy things") //little more

	  time(play.api.libs.json.Json.toJson(v),GREEN + "play") //look like init something it's very long 60ms
	  time(play.api.libs.json.Json.toJson(v),GREEN + "play") //avg 0.1ms
	  time(play.api.libs.json.Json.toJson(v),GREEN + "play") //0.1 ms
	  time(play.api.libs.json.Json.toJson(v).toString,GREEN + "play try to avoid lazy things") // little more

	  println("second object")

	  time(v2.asJson,BLUE + "circe") //avg 6-8 ms on my computer
	  time(v2.asJson,BLUE + "circe") // avg 6-8 ms on my computer
	  time(v2.asJson,BLUE + "circe") // idem
	  time(v2.asJson.toString,BLUE + "circe try to avoid lazy things") // idem

	  time(play.api.libs.json.Json.toJson(v2),GREEN + "play") //avg 0.1ms
	  time(play.api.libs.json.Json.toJson(v2),GREEN + "play") //avg 0.1ms
	  time(play.api.libs.json.Json.toJson(v2).toString,GREEN + "play  try to avoid lazy things") //0.1 ms
  }

}



/*
Thing you maybe want to put into your build.sbt
name := "CircePoc"

version := "1.0"

scalaVersion := "2.11.7"

resolvers += "Typesafe Repo" at "http://repo.typesafe.com/typesafe/releases/"

libraryDependencies ++= Seq(
  "io.circe" %% "circe-core" % "0.1.1",
  "io.circe" %% "circe-generic" % "0.1.1",
  "io.circe" %% "circe-jawn" % "0.1.1",
  "com.typesafe.play" %% "play-json" % "2.3.4"
)




*/

Here's what I'm seeing after a few warmup rounds:

circe elapsed time :0.062ms
circe elapsed time :0.045ms
circe elapsed time :0.04ms
circe try to avoid lazy things elapsed time :0.086ms
play elapsed time :0.122ms
play elapsed time :0.08ms
play elapsed time :0.074ms
play try to avoid lazy things elapsed time :0.124ms
second object
circe elapsed time :0.036ms
circe elapsed time :0.03ms
circe elapsed time :0.032ms
circe try to avoid lazy things elapsed time :0.074ms
play elapsed time :0.079ms
play elapsed time :0.071ms
play  try to avoid lazy things elapsed time :0.117ms
res13: String = {"ip":"3","remote_ip":"4"}

And with the circe 0.2.0 snapshot:

scala> perf.Test.run
circe elapsed time :0.059ms
circe elapsed time :0.034ms
circe elapsed time :0.038ms
circe try to avoid lazy things elapsed time :0.102ms
play elapsed time :0.145ms
play elapsed time :0.08ms
play elapsed time :0.092ms
play try to avoid lazy things elapsed time :0.109ms
second object
circe elapsed time :0.035ms
circe elapsed time :0.032ms
circe elapsed time :0.032ms
circe try to avoid lazy things elapsed time :0.06ms
play elapsed time :0.061ms
play elapsed time :0.057ms
play  try to avoid lazy things elapsed time :0.078ms
res13: String = {"ip":"3","remote_ip":"4"}

So circe generally looks a little faster in both cases, but you'd want to use a more sophisticated approach to timing to take that as meaningful.