Json error parsing into case class, json array - scala

Question

I am trying to parse this json object and I ran a unit test and I got this error Error: Error when parsing result of 'listdescriptors': {"obj":[{"msg":["error.expected.jsarray"],"args":[]}]}! [info] at org.bitcoins.rpc.client.common.Client.parseResult(Client.scala:455). I think the problem may be that I'm parsing the json file into a case class incorectly.
Result:
{ (json object)
"wallet_name" : "str", (string) Name of wallet this operation was performed on
"descriptors" : [ (json array) Array of descriptor objects
{ (json object)
"desc" : "str", (string) Descriptor string representation
"timestamp" : n, (numeric) The creation time of the descriptor
"active" : true|false, (boolean) Activeness flag
"internal" : true|false, (boolean, optional) Whether this is an internal or external descriptor; defined only for active descriptors
"range" : [ (json array, optional) Defined only for ranged descriptors
n, (numeric) Range start inclusive
n (numeric) Range end inclusive
],
"next" : n (numeric, optional) The next index to generate addresses from; defined only for ranged descriptors
},
...
]
}
object JsonSerializers {
implicit val descriptorsClassReads: Reads[descriptorsClass] =
Json.reads[descriptorsClass]
implicit val listDescriptorsReads: Reads[listDescriptorsResult] =
Json.reads[listDescriptorsResult]
sealed abstract class WalletResult
case class listDescriptorsResult(
wallet_name: String,
descriptors: Vector[descriptorsClass]
) extends WalletResult
case class descriptorsClass(
desc: String,
timestamp: ZonedDateTime,
active: Boolean,
internal: Boolean,
range: Array[(Int, Int)],
next: Int
) extends WalletResult

Answer 1

Here is a working example without the ZonedDateTime. It is probably better to have it represented as a Long in case class and convert it to ZonedDateTime later only when you need to represent it as ZonedDateTime
import play.api.libs.json.{Json, Reads, Writes}
sealed abstract class WalletResult
case class ListDescriptorsResult(
wallet_name: String,
descriptors: Seq[DescriptorsClass]
) extends WalletResult
case class DescriptorsClass(
desc: String,
timestamp: Long,
active: Boolean,
internal: Boolean,
range: (Int, Int),
next: Int
) extends WalletResult
implicit val descriptorsClassReads: Reads[DescriptorsClass] =
Json.reads[DescriptorsClass]
implicit val listDescriptorsResultReads: Reads[ListDescriptorsResult] =
Json.reads[ListDescriptorsResult]
val jsonString =
"""
|{
| "wallet_name" : "str",
| "descriptors" : [
| {
| "desc" : "desc1",
| "timestamp" : 1657920976,
| "active" : true,
| "internal" : true,
| "range" : [
| 10,
| 20
| ],
| "next" : 10
| },
| {
| "desc" : "desc2",
| "timestamp" : 1657920976,
| "active" : true,
| "internal" : false,
| "range" : [
| 30,
| 40
| ],
| "next" : 20
| }
| ]
|}
|
""".stripMargin.replaceAll("\n","")
val jsValue = Json.parse(jsonString)
println(Json.fromJson[ListDescriptorsResult] (jsValue).get)
Here is the code in a scastie editor