Scala Slick - 省略 ID 列 (Auto_Increment)

Question

学了2个月的Scala，Slick，Akka，在做Akka的项目时遇到了问题...

// This case class is to use for parsing data from request
// case class UserTransaction(sender: String, recipient: String, amount: Int)

//This one is to use for reflecting database
case class UserTransactionDB(sender: String, recipient: String, amount: Int, id: Int)

class UserTransactionModelDB(tag: Tag) extends Table[UserTransactionDB](tag, "usertransaction")
{
    def id = column[Int]("id", O.PrimaryKey, O.AutoInc)
    def sender = column[String]("sender")
    def recipient = column[String]("recipient")

    def amount = column[Int]("amount")

    override def * =

        (sender, recipient, amount, id) <> (UserTransactionDB.tupled, UserTransactionDB.unapply)

}

我想像这样向 Akka 发送 POST 请求 (Json) :

{"sender" : "S" , "recipient" : "R", "amount" : 100}

现在，我只想使用一种情况 class UserTransaction（没有 UserTransactionDB 中的 "id" 字段），不仅要反映数据库，还要解析请求中的数据。这可能吗？

谢谢你，对不起我的英语！

Answer 1

尝试使用自定义格式...大致如下：

case class UserTransactionDB(sender: String, recipient: String, amount: Int, id: Int)

object MyJsonProtocol extends DefaultJsonProtocol {
  implicit object UserTransactionJsonFormat extends RootJsonFormat[UserTransactionDB] {
    def write(c: UserTransactionDB) =
      JsArray(JsString(c.sender), JsString(c.recipient), JsNumber(c.amount))

    def read(value: JsValue) = value match {
      case JsArray(Vector(JsString(sender), JsString(recipient), JsNumber(amount))) =>
        new UserTransactionDB(sender, recipient, amount.toInt)
      case _ => deserializationError("UserTransactionDB expected")
    }
  }
}

Scala Slick - 省略 ID 列 (Auto_Increment)

Scala Slick - Omit ID column (Auto_Increment)

scala

akka

slick