Circe support for playframework

How to get it

• Add dependency

For play 2.6.x

libraryDependencies += "com.dripower" %% "play-circe" % "2612.0"

For play 2.7.x

libraryDependencies += "com.dripower" %% "play-circe" % "2712.0"

For play 2.8.x

libraryDependencies += "com.dripower" %% "play-circe" % "2814.1"

Usage

package play.api.libs.circe

import io.circe.generic.auto._
import io.circe.syntax._
import play.api._
import play.api.mvc._

class CirceController(val controllerComponents: ControllerComponents) extends BaseController with Circe {

  case class Bar(bar: Int)
  case class Foo(foo: String, bar: Bar)

  val bar = Bar(1)
  val foo = Foo("foo", bar)

  //serve json
  def get = Action {
    Ok(foo.asJson)
  }

  //parse json to case class
  def post = Action(circe.json[Foo]) { implicit request =>
    val isEqual = request.body == foo
    Ok(isEqual.toString)
  }

  def postJson = Action(circe.json) { implicit request =>
    val isEqual = request.body == foo.asJson
    Ok(isEqual.toString)
  }

  def postTolerate = Action(circe.tolerantJson[Foo]) { implicit request =>
    val isEqual = request.body == foo
    Ok(isEqual.toString)
  }

  def postTolerateJson = Action(circe.tolerantJson) { implicit request =>
    val isEqual = request.body == foo.asJson
    Ok(isEqual.toString)
  }
}

FAQ

• If you want to customize the json output, you can provide an implicit Printer in scope (default is Printer.noSpaces):

import io.circe.Printer

implicit val customPrinter = Printer.spaces2.copy(dropNullValues = true)

• The Circe totally ignores the configured HttpErrorHandler and just uses DefaultHttpErrorHandler. If this not what you want, simply make a trait to override circeErrorHandler like this

class MyController @Inject() (val errorHandler: HttpErrorHandler, val controllerComponents: ControllerComponents) extends BaseController with Circe {
  override def circeErrorHandler = errorHandler
}