Scala 播放框架JSON转换器,如何使用递归路径(jsPath)?
假设我有这样一个JSON:Scala 播放框架JSON转换器,如何使用递归路径(jsPath)?,scala,playframework,Scala,Playframework,假设我有这样一个JSON: { "name" : "Watership Down", "location" : { "lat" : 51.235685, "long" : -1.309197 }, "residents" : [ { "name" : "Fiver", "age" : 4, "role" : null }, { "name" : "Bigwig", "age" : 6, "role" : "Ows
{
"name" : "Watership Down",
"location" : {
"lat" : 51.235685,
"long" : -1.309197
},
"residents" : [ {
"name" : "Fiver",
"age" : 4,
"role" : null
}, {
"name" : "Bigwig",
"age" : 6,
"role" : "Owsla"
} ]
}
val transformerRecursive = (__ \\ 'name).json.update(of[JsValue].map(a => JsString("x")))
如果我这样做
val transformer1 = (__ \ 'name).json.update(of[JsValue].map(a => JsString("x")))
要将名称
字段更改为“x”
,它可以正常工作
但是如果我想递归地将所有名称更改为“x”
,我想我可以使用递归jsPath,如下所示:
{
"name" : "Watership Down",
"location" : {
"lat" : 51.235685,
"long" : -1.309197
},
"residents" : [ {
"name" : "Fiver",
"age" : 4,
"role" : null
}, {
"name" : "Bigwig",
"age" : 6,
"role" : "Owsla"
} ]
}
val transformerRecursive = (__ \\ 'name).json.update(of[JsValue].map(a => JsString("x")))
但当我尝试时,我得到了以下错误:
scala>jsobject.transform(transformerRecursive)
res1:play.api.libs.json.JsResult[play.api.libs.json.JsObject]=JsError(List(//name,List(ValidationError)(List(error.path.result.multiple),WrappedArray())))
我应该如何在playframework中使用带有JSON Transformer的递归路径 正如@Irundia所说,您需要迭代数组并更新每个值(为此使用
Reads.list
):
感谢@andrey.ladniy,我成功地解决了我想清空嵌套JsArray的问题。下面是一个如何做到这一点的示例,仅适用于可能找到任何帮助的任何人:
import play.api.libs.json._
case class D(yay: String, nay: String)
case class C(ds: Seq[D], baz: Boolean)
case class B(cs: Seq[C], bar: Int)
case class A(b: B, foo: String)
implicit val formatD: OFormat[D] = Json.format
implicit val formatC: OFormat[C] = Json.format
implicit val formatB: OFormat[B] = Json.format
implicit val formatA: OFormat[A] = Json.format
val foo = A(
B(Seq(C(Seq(D("foo", "bar")), true), C(Seq(D("oof", "rab")), false)), 42),
"test"
)
val dsIgnoringReads =
(__ \ "b" \ "cs").json.update(Reads.seq((__ \ "ds").json.update(Reads.pure(JsArray()))).map(JsArray))
dsIgnoringReads.reads(Json.toJson(foo)).get
这就产生了
res0: play.api.libs.json.JsObject =
{"b":{"cs":[{"ds":[],"baz":true},{"ds":[],"baz":false}],"bar":42},"foo":"test"}
我认为错误报告了
“name
属性有多个匹配项。您可能需要对它们进行迭代并单独更新