Spark DataFrame Schema to Scala Case Class Generator

Schema2CaseClass.scala

object Schema2CaseClass {

  import org.apache.spark.sql.types._

  case class RecFieldRes(fieldStr: String, additionalCc: Option[String] = None)

  case class CcRes(cc: String, additional: List[String])

  def schema2Cc(schema: StructType, className: String): String = {
    val res = CcRes(s"case class $className (\n", Nil)
    val res1 = schema.map(field).foldLeft(res)((b, a) => b.copy(b.cc + s"\n${a.fieldStr},", b.additional ++ a.additionalCc))
    res1.cc.stripSuffix(",") + "\n)\n" + res1.additional.mkString("\n\n")
  }

  private def field(sf: StructField): RecFieldRes = {

    def fd: String => String = fieldDef(sf)

    sf.dataType match {
      case at: ArrayType => at.elementType match {
        case s: StructType => RecFieldRes(fd(s"Seq[${sf.name.toLowerCase.capitalize}]"), Some(schema2Cc(s, sf.name.toLowerCase.capitalize)))
        case _ => RecFieldRes(fd(s"Seq[${primitiveFiledType(at.elementType)}]"))
      }
      case mt: MapType => RecFieldRes(fd("Map")) //TODO
      case st: StructType => RecFieldRes(fd(sf.name.toLowerCase.capitalize), Some(schema2Cc(st, sf.name.toLowerCase.capitalize)))
      case pt => RecFieldRes(fd(primitiveFiledType(pt)))
    }
  }

  private def primitiveFiledType(dt: DataType): String = dt match {
    case _: ByteType => "Byte"
    case _: ShortType => "Short"
    case _: IntegerType => "Int"
    case _: LongType => "Long"
    case _: FloatType => "Float"
    case _: DoubleType => "Double"
    case _: DecimalType => "java.math.BigDecimal"
    case _: StringType => "String"
    case _: BinaryType => "Array[Byte]"
    case _: BooleanType => "Boolean"
    case _: TimestampType => "java.sql.Timestamp"
    case _: DateType => "java.sql.Date"
    case _ => "String"
  }

  private def fieldDef(sf: StructField)(ft: String): String = sf match {
    case x if x.nullable && !x.dataType.isInstanceOf[ArrayType] && !x.dataType.isInstanceOf[MapType] =>
      s"  ${sf.name}: Option[$ft]"
    case _ => s"  ${sf.name}: $ft"
  }
}

Thanks for the contribution