Getting "No Json serializer found for type scala.concurrent.Future..." exception in Scala Play application -

i trying web application scala play 2, slick 3 , postgresql. purpose return json controller.

these dependencies -

librarydependencies ++= seq(     "org.postgresql" % "postgresql" % "9.4-1201-jdbc41",     "com.typesafe.slick" %% "slick" % "3.0.0",     "com.typesafe.play" %% "play-slick" % "1.0.1",     "com.typesafe.play" %% "play-slick-evolutions" % "1.0.1",     specs2 % test ) 

this 1 of model -

package models  import play.api.libs.json.json import slick.driver.postgresdriver.api._  import play.api.mvc._ import play.api.libs.json._ import play.api.libs.functional.syntax._  case class user (id: string, name: string)  class usermodel (tag: tag) extends table[user](tag, "users") {     def id = column[string]("id", o.primarykey)     def email = column[string]("email")      def * = (id, email) <> (user.tupled, user.unapply _) }  object users extends modelinit {     lazy val users = tablequery[usermodel]     implicit val userformat = json.format[user]      def = {         db.run(users.result)     } } 

this controller -

package controllers  import models.users import play.api.libs.json.json import play.api.mvc._  class application extends controller {     def index = action {         val users = users.all         val json = json.tojson(users)         println(json)         ok(views.html.index("your new application ready."))     } } 

currently getting following exception-

no json serializer found type scala.concurrent.future[seq[models.usermodel#tableelementtype]]. try implement implicit writes or format type.     class application extends controller { 8       def index = action { 9           val users = users.all 10          val json = json.tojson(users)  11          println(json) 12          ok(views.html.index("your new application ready.")) 13      } 14} 

you need :

class application extends controller {     def index = action {         val users = users.all         users.map(js => println(json.tojson(js))) // give future[unit] instead of printing can future[json], i.e can map 1 future future.         ok(views.html.index("your new application ready."))     } } 

or

you can await on future (not recommended) , serialize it.

import concurrent.duration._ val users = await.result(users.all,5.seconds) val json = json.tojson(users) println(json) 

ps: have not tested seems solution.