playjsonsnake Apache 2 badge

playjsonsnake is a micro-library that adds snake case support to play-json, the JSON library in Play.


Add this to your sbt build definitions, such as in build.sbt:

libraryDependencies += "com.beamly" %% "playjsonsnake" % "1.0.1"

For other build systems see the dependency information on Maven Central:

How to Use

Wrap play-json's OFormat (such as one returned by Json.format) with SnakeCaseJson.format.

The returned OFormat will serialise to and deserialise from snake case JSON field names:

scala> :pa
// Entering paste mode (ctrl-D to finish)

import playjsonsnake._
import play.api.libs.json._

final case class Foo(i: Int, abcDefGhi: Int)
object Foo {
  implicit val jsonFormat: OFormat[Foo] = SnakeCaseJson.format(Json.format[Foo])

// Exiting paste mode, now interpreting.

import playjsonsnake._
import play.api.libs.json._
defined class Foo
defined object Foo

scala> Json toJson Foo(123, 456)
res0: play.api.libs.json.JsValue = {"i":123,"abc_def_ghi":456}

scala> Json.fromJson[Foo](Json parse """{ "i" : 123, "abc_def_ghi" : 456 }""")
res1: play.api.libs.json.JsResult[Foo] = JsSuccess(Foo(123,456),)

There are also wrappers for Reads and OWrites, in the form of SnakeCaseJson.reads and SnakeCaseJson.writes.


  • Scala 2.11.x or 2.10.x
  • play-json 2.5.x


Copyright 2016 Beamly

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.