CSV Serializer

csv_serialize.scala

package com.socrata.util

import java.io.StringWriter
import com.github.tototoshi.csv.CSVWriter

trait CSVSerializable[T] {
  def getListOfValues(value: T): List[String]
}

object CSVSerializer {
  def serialize[T: CSVSerializable](value: T): String = {
    val stringWriter = new StringWriter
    val writer = CSVWriter.open(stringWriter)

    val fields = implicitly[CSVSerializable[T]].getListOfValues(value)
    writer.writeRow(fields)

    writer.close()
    stringWriter.toString
  }

  def serializeAll[T: CSVSerializable](values: Traversable[T]): String = {
    val stringWriter = new StringWriter
    val writer = CSVWriter.open(stringWriter)

    val serializable = implicitly[CSVSerializable[T]]

    values.foreach(x => writer.writeRow(serializable.getListOfValues(x)))

    writer.close()
    stringWriter.toString
  }
}

Goal.scala

object DeepGoal {
  implicit val deepGoalCodec = AutomaticJsonCodecBuilder[DeepGoal]

  def apply(goal:GoalWithId, prevailingMeasure:Option[MeasureWithId]) = {
    new DeepGoal(goal.id.id,
             goal.model.status,
             goal.model.name,
             goal.model.agencies,
             goal.model.relatedDatasets,
             goal.model.isPublic,
             goal.model.metadata,
             prevailingMeasure,
             goal.model.relatedMeasures,
             goal.model.baseDashboard,
             goal.model.updatedAt,
             goal.model.createdAt,
             goal.model.version,
             goal.model.createdBy)

  }

  implicit object CSVSerializableDeepGoal extends CSVSerializable[DeepGoal] {
    override def getListOfValues(value: DeepGoal): List[String] = {
      // TODO: Add required fields
      val fields = List(value.status, value.name, value.createdAt, value.updatedAt)

      val optionalToString = (x: Option[Any]) => x.map(_.toString).orNull

      fields
        .map(optionalToString)
        .filterNot(_.equals(null))
    }
  }
}

object CSVSerializable {
  def withoutHeaders[T](contentF: T => List[String]): CSVSerializable[T] = new CSVSerializable[T] {
      def getListOfValues(value: DeepGoal): List[String] = contentF(value)
      val getHeaders: Option[List[String]] = None
    }

  def withHeaders[T](headers: String*)(contentF: T => List[String]): CSVSerializable[T] = new CSVSerializable[T] {
    def getListOfValues(value: DeepGoal): List[String] = contentF(value)
    val getHeaders: Option[List[String]] = Some(headers.toList)
  }
}

implicit val csvDeepGoal = CSVSerialize.withHeaders[DeepGoal]("status", "name", "createdAt", "updatedAt") { value =>
  List(value.status, value.name, value.createdAt, value.updatedAt).map(_.fold("")(_.toString))
}

implicit val csvListString = CSVSerialize.withoutHeaders[List[String](identity)

def list(format: String)()(requestEnv:Triple[HttpServletRequest,Domain,AuthenticatedUser]) = {
      val (request, domain, user) = requestEnv

      val reader = self.GoalReader(domain)

      val goals = Array(FourByFour("iryy-8ukh"), FourByFour("ua8x-w82w"))
        .map(reader.getDeeply)
        .flatMap(_.right.getOrElse(null))
        .filterNot(_.equals(null))

      val content = format match {
        case "json" => renderJson(goals)
        case "csv"  => CSVSerializer.serializeAll(goals)
      }

      getSuccess(content, None)
    }