如何在Scala中从JSON生成合并值列表并按条件拆分输出？

输入JSON #

[{    
    "Orders": {        
        "orderid": {            
            "path": "order_id",            
            "type": "CHAR",            
            "is_explode_required": "N"        
        },        
        "customerId": {            
            "path": "customers.customerId",            
            "type": "CHAR",            
            "is_explode_required": "N"        
        },        
        "offerid": {            
            "path": "Offers.Offerid",            
            "type": "LIST",            
            "is_explode_required": "Y"        
    }    },    
    "products": {        
        "productid": {            
            "path": "product_id",            
            "type": "CHAR",            
            "is_explode_required": "N"        
        },        
        "productName": {            
            "path": "products.productname",            
            "type": "CHAR",            
            "is_explode_required": "N"        
        }    
    }
}]

需求说明 #

处理上述JSON中的Orders节点，生成两列结果：

• output：拼接Orders下所有子节点的path值，用逗号分隔
• explode_output：仅拼接Orders下is_explode_required属性为"Y"的子节点的path值

Scala实现代码（基于Play JSON库） #

import play.api.libs.json._

object JsonProcessor extends App {
  // 输入JSON字符串
  val inputJson = """[{    
      "Orders": {        
          "orderid": {            
              "path": "order_id",            
              "type": "CHAR",            
              "is_explode_required": "N"        
          },        
          "customerId": {            
              "path": "customers.customerId",            
              "type": "CHAR",            
              "is_explode_required": "N"        
          },        
          "offerid": {            
              "path": "Offers.Offerid",            
              "type": "LIST",            
              "is_explode_required": "Y"        
      }    },    
      "products": {        
          "productid": {            
              "path": "product_id",            
              "type": "CHAR",            
              "is_explode_required": "N"        
          },        
          "productName": {            
              "path": "products.productname",            
              "type": "CHAR",            
              "is_explode_required": "N"        
          }    
      }
  }]"""

  // 解析JSON
  val parsedJson = Json.parse(inputJson)

  // 提取Orders节点下的所有子对象
  val ordersChildren = (parsedJson(0) \ "Orders").as[JsObject].values

  // 生成output列：所有path值拼接
  val outputCol = ordersChildren.map(_.as[JsObject]("path").as[String]).mkString(",")

  // 生成explode_output列：筛选符合条件的path值拼接
  val explodeOutputCol = ordersChildren
    .filter(child => (child \ "is_explode_required").as[String] == "Y")
    .map(_.as[JsObject]("path").as[String])
    .mkString(",")

  // 打印结果
  println("output| explode_output")
  println(s"$outputCol|$explodeOutputCol")
}

依赖配置 #

如果使用Play JSON，需要在build.sbt中添加以下依赖：

libraryDependencies += "com.typesafe.play" %% "play-json" % "2.9.2"

预期输出 #

output| explode_output
order_id,customers.customerId,Offers.Offerid|Offers.Offerid

内容的提问来源于stack exchange，提问作者Shankar Panda