Required fields in scala map -


i have jsonmap : map[string , any] , extracting 3 required field map

 //case class exception handling case class parserexception(message: string) extends exception(message)   val id = jsonmap.getorelse("id", throw parserexception("id required."))  val type = jsonmap.getorelse("type", throw parserexception("type required."))  val location = jsonmap.getorelse("location", throw parserexception("location required."))

if json don't have required value exception raised.is there better way in scala implement required field extract ?

expected : if field missing json , code should throw exception..if mandatory fields available program flow should move next step.

lift map partial function missing keys mapped none , defined keys some(value); example,

scala> val m = map("id" -> 1, "loc" -> 2) m: scala.collection.immutable.map[string,int] = map(id -> 1, loc -> 2)  scala> m.lift("id") res0: option[int] = some(1)  scala> m.lift("missing") res1: option[int] = none

note lift once, viz. val ml = m.lift, query many, e.g. ml("id")


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