Scala Play readNullable can't read Map types

Question

I am trying to use play.api.lib.json to convert a json to my object. But then this happend...

  case class Foo(foo:Option[Map[String,String]])
  case class Bar(bar:String,foo:Foo)

  def barJsonToModel(foobarJson:JsValue):Bar = {
     implicit val fooReads: Reads[Foo] = (
        ( JsPath \ "foo" ).readNullable[Map[String,String]]
     )(Foo.apply _)
  }

Expression of type Reads[Option[Map[String,String]]] doesn't comfort to expect type Reads[Foo]

I think that your problem is similar to that in [this question](https://stackoverflow.com/questions/40786742/play-framework-json-reads-for-a-single-attribute-case-class). Also, since your class `Foo` is only a wrapper around a single value, you can remove it and include your `foo: Option[Map[String, String]])` directly in your class `Bar`. — Jack Bourne, Jun 21 '19 at 07:46
Possible duplicate of [Play framework: JSON Reads for a single-attribute case class](https://stackoverflow.com/questions/40786742/play-framework-json-reads-for-a-single-attribute-case-class) — Jack Bourne, Jun 21 '19 at 07:47

score 0 · Answer 1 · edited Jan 03 '21 at 15:20

0

You are using the functional syntax of play-json, but so an import is missing before:

import play.api.libs.functional.syntax._

edited Jan 03 '21 at 15:20

Tomer Shetah

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answered Jun 21 '19 at 06:41

cchantep

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Scala Play readNullable can't read Map types

1 Answers1