Issue with elegantly accumulating errors using Either[String, B] in Scala - scala

Question

I am trying to parse a csv row here and each field can be a different type. To handle the error accumulation I am using Either[String, B] where the String is an error message and B is the value. The issue here is that B can be different types, Option[Int], String, Array[String], resulting in my Map being type (String, Either[String,java.io.Serializable]) effectively making the Map unreusable. Is there a way (I'm definitely sure there is) to more elegantly accumulate errors while also reusing those values to populate properties on an object?
override def parseCsv(implicit fields: Map[String, String]): Either[String, User] = {
val parsedValues = Map(Headers.Id -> getFieldAsString(Headers.Id),
Headers.FirstName -> getFieldAsString(Headers.FirstName),
Headers.LastName -> getFieldAsString(Headers.LastName),
Headers.Email -> getFieldAsString(Headers.Email),
Headers.TimeZone -> getFieldAsString(Headers.TimeZone),
Headers.Region -> getOption(Headers.Region),
Headers.Phone -> getOption(Headers.Phone),
Headers.ProfileImage -> getFieldAsString(Headers.ProfileImage),
Headers.Roles -> getFieldAsArray(Headers.Roles))
val errors = parsedValues.collect { case (key, Left(errors)) => errors }
if (!errors.isEmpty) Left(errors.mkString(", "))
else {
val user = new User
user.id = getFieldAsString(Headers.Id).right.get
user.firstName = getFieldAsString(Headers.FirstName).right.get
user.lastName = getFieldAsString(Headers.LastName).right.get
user.email = getFieldAsString(Headers.Email).right.get
user.timeZone = getFieldAsString(Headers.TimeZone).right.get
user.phoneNumber = (for {
region <- getOption(Headers.Region).right.get
phone <- getOption(Headers.Phone).right.get
_ = validatePhoneNumber(phone, region)
} yield {
new PhoneNumber(region, phone)
}).orNull
user.profileImageUrl = getFieldAsString(Headers.ProfileImage).right.get
user.roles = getFieldAsArray(Headers.Roles).right.get
Right(user)
}
}

Answer 1

Create case classes for all types of Bs. These case classes must extend some common trait. While populating the user object just pattern match and retrieve values.
sealed trait Result {
val paramName: String
}
case class OptionInt(override val paramName: String, value: Option[Int]) extends Result
case class ArrayString(override val paramName: String, value: Array[String]) extends Result
case class StringValue(override val paramName: String, value: String) extends Result
now the final type would be like Either[String, Result]
after parsing the whole file create a List[Result]
If you are expecting age as Option[Int] and firstName as String then do this
list.foreach { result =>
result match {
case Option("age", value) => userId.age = value.getOrElse(defaultAge)
case StringValue("firstName", value) => userId.firstName = value
case StringValue("email", value) => userId.email = value
case _ => //do nothing
}
}