我遇到了序列化模型的问题:MyModel:
case class DocumentModel(
documentId: Option[Int] = None,
title: String,
...
responsibleList: Option[Seq[UserModel]], // No problem
preConditions: Option[Seq[Object]], // Problem occurs here
postConditions: Option[Seq[Object]] // Problem occurs here
)
object DocumentModel {
implicit val documentFormat = Jsonx.formatCaseClass[DocumentModel]
}
responsibleList
,preConditions
以及postConditions
都没有存储在数据库中,它们只用作帮助列表。我继续在我的控制器中填写这些列表,以便通过JSON
将其发送回前端:
val document = for {
newDocument <- documentDTO.getDocument(documentId, clientId)
responsibleList <- raciDocumentDTO.getResponsible_Documents(documentId)
...
preConditions <- conditionController.getPreConditions(documentId)
postConditions <- conditionController.getPostConditions(documentId)
} yield (newDocument, responsibleList, ..., preConditions, postConditions)
document.map({ case (newDocument, responsibleList, ..., preConditions, postConditions) =>
val temp = newDocument.map(docu => {
...
val doc = new DocumentModel(
docu.documentId,
docu.title,
...
Some(responsibleList),
Some(preConditions),
Some(postConditions)
)
doc
})
Ok(Json.obj(
"document" -> temp,
))
})
我怀疑它与Option[Seq[Object]]
或Option[Seq[Any]]
有关。编译器抛出一个错误:由于preConditions
和postConditions
可以是来自各种instances/objects
的models
,我无法明确说明它应该是哪个模型。有这个问题的解决方案还是我必须走另一条路?提前致谢!
UPDATE
我补充说:
trait Condition
object Condition {
import play.api.libs.json._
implicit val conditionWrites: Writes[Condition] = Writes[Condition] {
case a: DocumentModel => JsObject(Seq("DocumentModel" -> Jsonx(a)))
case b: ProcessModel => JsObject(Seq("ProcessModel" -> Jsonx(b)))
case c: ProcessInstanceModel => JsObject(Seq("ProcessInstanceModel" -> Jsonx(c)))
}
}
在我的模型中:
case class DocumentModel(
documentId: Option[Int] = None,
title: String,
...,
responsibleList: Option[Seq[UserModel]],
preConditions: Option[Seq[Condition]],
postConditions: Option[Seq[Condition]]
) extends Condition
它仍然留下这个错误消息:
这是我第一次遇到这样的问题,老实说我有点困惑。
更新2
我已经像你提到的那样尝试过,但它仍然会抛出相同的错误。
我的代码看起来像这样:
UPDATE
我实施了建议的更改,并将问题缩小到这个范围:
trait Condition
object Condition {
implicit val conditionWrites: Writes[Condition] = Writes[Condition] {
case a: DocumentModel => JsObject(Seq(
"documentId" -> Json.toJson(a.documentId),
"title" -> Json.toJson(a.title),
...
"responsibleList" -> Json.toJson(a.responsibleList),
"preConditions" -> Json.toJson(a.preConditions),
"postConditions" -> Json.toJson(a.postConditions)
))
case b: ...
}
}
当我这样做时,我收到以下错误消息:
所以我认为implicit read
可能会丢失。所以我补充说:
object Condition {
implicit val conditionReads: OFormat[Condition] = Json.format[Condition] // New
implicit val conditionWrites: Writes[Condition] = Writes[Condition] {
case a: DocumentModel => JsObject(Seq(
"documentId" -> Json.toJson(a.documentId),
"title" -> Json.toJson(a.title),
...
但是,在运行代码时,我得到了这个:
No unapply or unapplySeq function found
[error] implicit val conditionReads: OFormat[Condition] = Json.format[Condition]
建议解决这个问题的方法是将我的object condition
改为case class condition
。但是,这会破坏创建这种通用trait/object
的整个目的。
让所有“条件”模型扩展具有JSON可写的特征。例如,
trait Condition
object Condition {
implicit val conditionWrites: Writes[Condition] = Writes[Condition] {
case a: PreConditionA => JsObject(Seq("field" -> JsString(a.stringValue))) //or whatever
case b: PreConditionB => //...
//etc...
case x: PostConditionX => //...
case y: PostConditionY => //...
//etc...
}
}
case class PreConditionA(stringValue: String) extends Condition
//etc.
然后在DocumentModel
中,将条件的类型更改为Condition
特征:
case class DocumentModel(
documentId: Option[Int] = None,
title: String,
//...
responsibleList: Option[Seq[UserModel]],
preConditions: Option[Seq[Condition]],
postConditions: Option[Seq[Condition]]
)
您可能必须将序列化语法转换为Jsonx的任何语法,但希望它足够相似并且您可以理解。