Question

我正在使用Reactivemongo驱动程序（使用Scala）编写Play 2.3.2应用程序。我有存储所有用户数据的recommendation.user集合。一份文件具有以下形式：

{
"_id" : ObjectId("542e67e07f724fc2af28ba75"),
    "id" : "",
    "email" : "luigi@gmail.com",
    "tags" : [
        {
            "tag" : "Paper Goods:Liners - Baking Cups",
            "weight" : 2,
            "lastInsert" : 1412327492874
        },
        {
            "tag" : "Vegetable:Carrots - Jumbo",
            "weight" : 4,
            "lastInsert" : 1412597883569
        },
        {
            "tag" : "Paper Goods:Lialberto- Baking Cups",
            "weight" : 1,
            "lastInsert" : 1412327548205
        },
        {
            "tag" : "Fish:Swordfish Loin Portions",
            "weight" : 3,
            "lastInsert" : 1412597939124
        },
        {
            "tag" : "Vegetable:Carrots - alberto@gmail.com",
            "weight" : 2,
            "lastInsert" : 1412597939124
        }
    ]
}

现在我正在编写一个返回特定用户的所有标签的方法。我回复了JSOn的回应。在游戏中如何创建动态json？我的回归json有以下形式：

 {
       "tags": [
         {"tag": "tag1"},
         {"tag": "tag2"}
               ]
 }

这是我的方法实现：

def userTag(user: String) = Action.async {
         //obtain all the users saved in the db.
         val allUser : Future[Option[User]] = Users.find(Json.obj("email" -> user)).one
         val futureComputation = allUser map {
                                        (user: Option[User]) =>
                                          user match {
                                            case Some(x) => x.tags  match {
                                              case Some(userTags) => val tags: List[Tag] =  userTags.map{tag: (Tag, Double, Long) => tag._1} //obtain all the Tag objects
                                               //here for every element in the tags variable i want to add it add the json.             
                                              case None => Ok(Json.obj()) //return an empty json.
                                            }
                                            case None => Ok(Json.obj()) //return an empty json
                                          }


         }
         futureComputation

     }

我如何解决我的问题？

Answer 1

解决使用：

def userTag(user: String) = Action.async {
         //obtain all the users saved in the db.
         val allUser : Future[Option[User]] = Users.find(Json.obj("email" -> user)).one
         val futureComputation = allUser map {
                                        (user: Option[User]) =>
                                          user match {
                                            case Some(x) => x.tags  match {
                                              case Some(userTags) => val tags =  userTags.map{tag: (Tag, Double, Long) => val t = tag._1; t.category + ":" + t.attr} //obtain all the Tag objects
                                                                                    val arrayTags = for(tag <- tags) yield{Json.obj("tag" -> tag)} //crete the array json
                                                                                    Ok(Json.obj("tags" -> arrayTags)) //return the json corresponding to the user.

                                              case None => Ok(Json.obj()) //return an empty json.
                                            }
                                            case None => Ok(Json.obj()) //return an empty json
                                          }


         }
         //return the Future computation JSON responce.
         futureComputation

     }

使用play创建动态JSON

1 个答案: