仅公开 REST JSON 服务中的字段子集。玩框架，scala

Question

我有基于 JSON 和 play 框架的 scala REST 服务。我有用户案例 class

case class User(_id: BSONObjectID, username: String,password: String,creationTime: org.joda.time.DateTime)

和

object User{
val userReads: Reads[User] = (
(JsPath \ "username").read[String] (minLength[String](4) keepAnd maxLength[String] (32) ) and
(JsPath \ "password").read[String] (minLength[String](8) keepAnd maxLength[String] (32) ) 
?????)(User.apply _)

val userWrites: Writes[User] = ....
implicit val userFormat: Format[User] = Format (userReads, userWrites)
}

在注册期间（通过 REST API）我需要验证传入 json。我只需要用户名和密码，不需要 _id、creationTime 等。如何正确编写读取、写入以仅验证字段的子集（请完成读取并在您的代码中替换“??????”）？

Answer 1

定义一个单独的 class，比方说 RegistrationUser 并为此 class 定义 JSON 读取和写入：

 case class RegistrationUser(userName: String, password: String)

在数据库层你可以有这样的class：

 case class DbUser(_id: BSONObjectID,
                   username: String,
                   password: String,
                   creationTime: org.joda.time.DateTime)

然后您可以像这样在这些 class 之间映射：

 def saveUserToDb(registrationUser: RegistrationUser): Unit = {
   val dbUser = DbUser(
     _id          = BSONObjectID.generate,
     username     = registrationUser.username,
     password     = registrationUser.password,
     creationTime = DateTime.now
   )

   // Now you have your DbUser and you can save it to Mongo as you did before
 }

您不必在整个应用程序中使用相同的模型。为各个层使用单独的模型是完全有效的 - UI、服务、数据库、...

仅公开 REST JSON 服务中的字段子集。玩框架，scala

Expose only field subset in REST JSON Service. Play framework, scala

rest

json

scala

playframework