ReactiveMongo：管理序列字段答案

【问题标题】：ReactiveMongo: Manage Sequence fieldReactiveMongo：管理序列字段
【发布时间】：2015-01-12 12:35:00
【问题描述】：

我正在使用 Play Framework 和 ReactiveMongo 开发应用程序。我想为 Seq[Entities] 类型的模型字段编写 CRUD 操作

这是我的模型：

case class Person(_id: Option[BSONObjectID],
                  email: String,
                  password: String,
                  education: Option[Education])

object Lawyer {

  implicit val accountWrites: Writes[Person] = (
    (JsPath \ "_id").writeNullable[BSONObjectID] and
    (JsPath \ "email").write[String] and
    (JsPath \ "password").write[String] and
    (JsPath \ "education").writeNullable[Education]
  )(unlift(Person.unapply))

  implicit val accountReads: Reads[Person] = (
    (JsPath \ "_id").readNullable[BSONObjectID].map(_.getOrElse(BSONObjectID.generate)).map(Some(_)) and
    (JsPath \ "email").read[String] and
    (JsPath \ "password").read[String] and
    (JsPath \ "education").readNullable[Education]
  )(Person.apply _)

case class Education(status: String, certificates: Option[Seq[Certificate]])

object Education {

  implicit val educationFormat: Format[Education] = (
    (JsPath \ "status").format[String] and
    (JsPath \ "certificates").formatNullable[Seq[Certificate]]
  )(Education.apply, unlift(Education.unapply))

}

case class Certificate(id: Option[String] = Some(Random.alphanumeric.take(12).mkString),
                       name: String,
                       licenseCode: Option[String],
                       link: Option[String],
                       date: Date)

object Certificate {

  implicit val certificateFormat = Json.format[Certificate]

}

问题是：

1) 如何使用表单发布Certificate 实体？因为当我使用时：

def createCertificate(email: String, certificate: Certificate) = {
    val createCertificate = Json.obj(
      "$set" -> Json.obj(
        "education.certificates" -> certificate
      )
    )
    collection.update(
      Json.obj("email" -> email),
      createCertificate
    )
  }

它创建对象字段 {...} 的对象数组 [ {...}, ... ]

2) 如何从 Seq by ID 中删除 Certificate 实体？

谢谢

【问题讨论】：

标签： mongodb playframework reactivemongo

【解决方案1】：

1) 我假设您希望 createCertificate 将单个证书添加到（可能为空的）证书数组中，而不是使用单个证书创建数组。在这种情况下，您可以将 $set 运算符替换为 $push 运算符：

val createCertificate = Json.obj(
  "$push" -> Json.obj(
    "education.certificates" -> certificate
  )
)

2) 同样，要删除元素，您可以使用$pull 运算符：

def removeCertificate(email: String, certificateId: String) = {
  val removeCert = Json.obj(
    "$pull" -> Json.obj(
      "education.certificates" -> Json.obj("id" -> certificateId)
    )
  )
  collection.update(
    Json.obj("email" -> email),
    removeCert
  )
}

【讨论】：

谢谢明天试试 =)