Get scrum retro using Trello's API, in Scala

Retro.scala

import spray.json._
import DefaultJsonProtocol._


object Main extends App {
  class Card(val cardId: String, val name: String, val cardType: String, val effortHours: Double) {

    def formatCard(idx: Int): String = {
      idx + ". " + name + ": [" + effortHours + " hour(s)]"
    }
  }

  val authParams = Map(
    "key" -> "--key--",
    "token" -> "--token--"
  )

  def fetchCardsfromTrello(requestParams: Map[String, String]): String = {
    val searchURL = "https://trello.com/1/search"
    val response = requests.get(searchURL, params=requestParams)
    assert(response.statusCode == 200)

    response.text
  }

  def fetchCardDetailsfromTrello(cardId: String, requestParams: Map[String, String]): String = {
    val cardUrl = "https://api.trello.com/1/cards/" + cardId
    val response = requests.get(cardUrl, params=requestParams)
    assert(response.statusCode == 200)

    response.text
  }

  def getArchivedCardIds(days: String): List[String] = {
    var searchParams = Map(
      "query" -> ("is:archived board:GTD! edited:" + days + " sort:-edited"),
      "card_fields" -> "dateLastActivity",
      "cards_limit" -> "1000"
    )
    searchParams ++= authParams

    val cardsJson = fetchCardsfromTrello(searchParams).parseJson.asJsObject.fields("cards")
    cardsJson.convertTo[List[Map[String, String]]].map(card => card("id"))
  }

  def getEffort(customFields: List[Map[String, JsValue]]): Double = {
    val effortFieldId = "5bb36a7085958b30ecc1e0c2"
    var effort = 0.0

    customFields.foreach(field => {
      if (field("idCustomField").toString == effortFieldId) {
        effort = field("value").convertTo[Map[String, String]].apply("number").toFloat
      }
    })

    effort
  }

  def getCard(cardId: String): Card = {
    var cardParams = Map(
      "fields" -> "name,idList",
      "customFieldItems" -> "true"
    )
    cardParams ++= authParams

    val cardJson = fetchCardDetailsfromTrello(cardId, cardParams).parseJson.asJsObject.fields
    val customFields = cardJson("customFieldItems").convertTo[List[Map[String, JsValue]]]
    val cardName = cardJson("name").toString

    new Card(
      cardId,
      name = cardName.substring(1, cardName.length - 1),
      cardType = "",
      effortHours = getEffort(customFields)
    )
  }

  var daysLastEdited = "1"
  if (args.length > 0)
    daysLastEdited = args(0)

  val cardIds = getArchivedCardIds(daysLastEdited)

  cardIds.zipWithIndex foreach { case(cardId, idx) => {
    val card = getCard(cardId)
    println(card.formatCard(idx + 1))
  }}
}