Scala object to json string using lift-json

Question

I have a scala class like

class metrics{
 private var _moduleId: String = ""
 private var _blah1: String = ""
 private var _metadata: Map[String, String] = Map()
 def moduleId: String = _moduleId
 def moduleId_(value: String): Unit = {
 _moduleId = value
 }
 def blah1: String = _blah1
 def blah1_(value: String): Unit = {
 _blah1 = value
 }
 def metadata: Map[String, String] = _metadata
 def metadata_(value: Map[String, String]): Unit = {
 _metadata = value
 }
}

How do I use lift-json lib to convert metrics object like below to a json string.

val coda = new metrics()
 coda.blah1_("blah1")
 coda.moduleId_("module1")
 coda.metadata_(Map("p1"->"Alice","p2"->"Bob"))

When I try like this val json = Extraction.decompose(coda), I get a empty json {}. Any insight on how to do a conversion from scala pojo to json will be helpful.

Answer 1

The documentation for decompose says:

Decompose a case class into JSON

What you have there is not a case class. Case classes are the "pojo" in scala. You don't need to write all that boilerplate.

case class Metrics(moduleId: String = "", blah1: String = "", metadata: Map[String, String] = Map())
val coda = Metrics(
 blah1 = "blah1",
 moduleId = "module1",
 metadata = Map("p1"->"Alice","p2"->"Bob"))
val json = Extraction.decompose(coda)