How to partially parse a json string into my case class with spray json?

[Leon Ma]

input like this:

{

    "name" : "leon",

     "address" : "my address",

     "unknowfield1" : "blabla",

      "unknowfield2" : "blabla",

}

case class Info(name:String, address:String)

val myObject = jsonAst.convertTo[Info]

Anyone can provide some code snippet to do this?

Thanks

[Johannes Rudolph]

Hi Leon,

spray-json just ignores fields that are not mapped. So, nothing
special to do here. It may suffice to provide an

implicit val infoFormat = jsonFormat2(Info)

to get it working.

Johannes

-----------------------------------------------
Johannes Rudolph
http://virtual-void.net

[Leon Ma]

cool, I just tried and it works!

But if the json is like this

{

     "address" : "my address",

     "unknowfield1" : "blabla",

}

case class Info(name:String = "leon", address:String)

it seems the parser will complain about missing name even if I have a default value for it.

spray.json.DeserializationException: Object is missing required member 'name'

at spray.json.package$.deserializationError(package.scala:23)

at spray.json.ProductFormats$class.liftedTree1$1(ProductFormats.scala:489)

at spray.json.ProductFormats$class.spray$json$ProductFormats$$fromField(ProductFormats.scala:481)

at spray.json.ProductFormats$$anon$2.read(ProductFormats.scala:50)

at spray.json.ProductFormats$$anon$2.read(ProductFormats.scala:43)

at spray.json.JsValue.convertTo(JsValue.scala:32)

at com.ebay.raptor.proxy.LogHandler$$anonfun$receive$2.applyOrElse(LogService.scala:62)

at akka.actor.ActorCell.receiveMessage(ActorCell.scala:498)

How to resolve it?

Thanks

Ma Ling

在 2014年2月25日星期二UTC-8上午1时05分08秒，Johannes Rudolph写道：

[Johannes Rudolph]

On Tue, Feb 25, 2014 at 10:22 AM, Leon Ma <tutu...@gmail.com> wrote:
> cool, I just tried and it works!
>
> But if the json is like this
>
> {
>
> "address" : "my address",
> "unknowfield1" : "blabla",
>
>
> }
>
> case class Info(name:String = "leon", address:String)

Yes, Scala's default parameters are not supported. If you have
optional fields you need to change the `name` parameter to type
`Option[String]`.

--

[Leon Ma]

Got it! Thanks a lot!

在 2014年2月25日星期二UTC+8下午5时24分54秒，Johannes Rudolph写道：