Json.encode fails on Array[Byte]

[mushtaq]

Test

val bytes = "abc".getBytes()
Json.encode(bytes).toUtf8String

Error

io.bullet.borer.Borer$Error$Unsupported: The JSON renderer doesn't support byte strings (Output.ToByteArray index 0)

Related

All of the following works

Json.encode(bytes.head).toUtf8String
Cbor.encode(bytes.head).toByteArray
Cbor.encode(bytes).toByteArray

Workaround

implicit lazy val bytesEnc: Encoder[Array[Byte]] = targetSpecificEnc(
    cborEnc = Encoder.forByteArray,
    jsonEnc = Encoder.forArray[Byte]
  )

def targetSpecificEnc[T](cborEnc: Encoder[T], jsonEnc: Encoder[T]): Encoder[T] = { (writer, value) ⇒
  val enc = if (writer.target == Cbor) cborEnc else jsonEnc
  enc.write(writer, value)
}

We had to write an analogous target specific decoder for Array[Bytes]

[sirthias]

How would you expect raw bytes to be encoded in JSON?
Base64 String? Simple hex string? As an array of JSON numbers?
IMHO there is no clear and valuable default strategy here, or is there?

[mushtaq]

@sirthias I agree that there is no natural default. But getting a runtime error is not nice.

For us, any default will work because we will rarely exercise this path when using the REST/Json.

I would suggest we go ahead with Encoder.forArray[Byte] as the default because that is what most JSON libs do.

Also, in this case encoder, we do not need to define the decoder, and the following works fine:
Json.decode(Json.encode("abc".getBytes()).toByteArray).to[Array[Byte]].value