Converting JSON into Seq<String> in Scala-CodePudding

I'm new in Scala and trying to achieve the following using Scala's foldLeft() method or any other functional solution:

I have the following JSON:

 {
   "aspects": [
     {
       "name": "Name",
       "values": [
         "Phone"
       ]
     },
     {
       "name": "Color",
       "values": [
         "Red",
         "Black"
       ]
     },
     {
       "name": "Size",
       "values": [
         "6",
         "10"
       ]
     }
   ]
 }

I want to convert this into the following Seq<String>:

["Name:::Phone", "Color:::Red", "Color:::Black", "Size:::6", "Size:::10"]

I did that using Java style where aspects is an object representing the JSON:

 aspects.foreach(pair => {
   pair.values.foreach(value => {
     valuesList  = pair.name   ":::"   value
   })
 })

What is the best Scala's way to do this?

CodePudding user response：

It depends on the JSON library you are using, but once you have the aspects data in a suitable format the output can be generated is like this:

case class Aspect(name: String, values: Seq[String])

val aspects: Seq[Aspect] = ???

aspects.flatMap(a => a.values.map(a.name   ":::"   _))

I use json4s and jackson and the conversion code is basically just

val aspects = parse(json).extract[Seq[Aspect]]

Check the documentation for details, and check out other JSON libraries which may be more suitable for your application.

CodePudding user response：

Have not parsed the JSON since the object aspects has these values. Just manually constructing the case class and flatmapping it

scala> final case class Aspects(pairs:Seq[Pair])
defined class Aspects

 val namepair = Pair("Name",Seq("Phone"))
namepair: Pair = Pair(Name,List(Phone))

 val colorpair = Pair("Color",Seq("Red","Black"))
colorpair: Pair = Pair(Color,List(Red, Black))

 val sizepair = Pair("Size",Seq("6","10"))
sizepair: Pair = Pair(Size,List(6, 10))

 val aspects = Aspects(Seq(namepair,colorpair,sizepair))
aspects: Aspects = Aspects(List(Pair(Name,List(Phone)), Pair(Color,List(Red, Black)), Pair(Size,List(6, 10))))

aspects.pairs.flatMap(pair=>pair.values.map(value=>s"${pair.name}:::$value"))
res1: Seq[String] = List(Name:::Phone, Color:::Red, Color:::Black, Size:::6, Size:::10)