avdv / play-json-refined   0.6.1

Contributors Wanted Apache License 2.0 Website GitHub

Play JSON Reads/Writes instances for refined types

Scala versions: 2.12 2.11


Apache 2.0 license Github workflow status

Play JSON Reads/Writes instances for refined types. In other words, this library let’s you convert refined types to and from JSON.


Add the following to your build.sbt:

libraryDependencies += "de.cbley" %% "play-json-refined" % "<version>"

Replace <version> with the desired version, see https://mvnrepository.com/artifact/de.cbley/play-json-refined.


import eu.timepit.refined._
import eu.timepit.refined.auto._
import eu.timepit.refined.api._
import play.api.libs.json._
import de.cbley.refined.play.json._
Welcome to Scala 2.11.8 (Java HotSpot(TM) 64-Bit Server VM, Java 1.8.0_65).
Type in expressions for evaluation. Or try :help.

scala> type PosInt = Int Refined numeric.Positive
defined type alias PosInt

scala> val foo : PosInt = 42
foo: PosInt = 42

scala> Json.toJson(foo)
res0: play.api.libs.json.JsValue = 42

scala> Json.fromJson[PosInt](JsNumber(42))
res3: play.api.libs.json.JsResult[PosInt] = JsSuccess(42,)

scala> Json.fromJson[PosInt](JsNumber(-42))
res4: play.api.libs.json.JsResult[PosInt] =
JsError(List((,List(ValidationError(List(Predicate failed: (-42 >


Copyright 2016–2019 Sebastian Wiesner Copyright 2019 Claudio Bley

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at


Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.