Apache nifi Nifi JoltTransformJSON:在键名中保留下划线符号

我试图用ApacheNIFI编写一个转换json格式的jolt。我成功地转换了震动，但有一个属性缺少下划线：

输出：

          {
     "Source": {   //source is missing underscore. It should look like _Source
           "userName": "Lulu"
      }
  }

我的意见如下：

     {
        "user_name": "Lulu"
     }

[
        {
          "operation": "shift",
          "spec": {
               "user_name":"userName"
           }
        },
        {
          "operation": "modify-overwrite-beta",
          "spec": {         
              "_Source":{
                  "userName":"@(2,userName)"
               }
           }
         },
         { "operation": "remove", 
          "spec": { 

                    "userName": "" } 
               }
]

当前，我的震动表达式如下所示：

     {
        "user_name": "Lulu"
     }

[
        {
          "operation": "shift",
          "spec": {
               "user_name":"userName"
           }
        },
        {
          "operation": "modify-overwrite-beta",
          "spec": {         
              "_Source":{
                  "userName":"@(2,userName)"
               }
           }
         },
         { "operation": "remove", 
          "spec": { 

                    "userName": "" } 
               }
]

如何保持下划线登录属性“Source”

---

我一直在琢磨这部分。我想知道我在摇晃的表情中遗漏了什么。提前谢谢，伙计们，我想下划线可能是该运算符中的某种特殊字符，请尝试在源代码前面使用双反斜杠：

[
  {
    "operation": "shift",
    "spec": {
      "user_name": "userName"
    }
        },
  {
    "operation": "modify-overwrite-beta",
    "spec": {
      "\\_Source": {
        "userName": "@(2,userName)"
      }
    }
         },
  {
    "operation": "remove",
    "spec": {
      "userName": ""
    }
  }
]

---

我认为下划线可能是该运算符中的某种特殊字符，请尝试在_Source前面使用双反斜杠：

[
  {
    "operation": "shift",
    "spec": {
      "user_name": "userName"
    }
        },
  {
    "operation": "modify-overwrite-beta",
    "spec": {
      "\\_Source": {
        "userName": "@(2,userName)"
      }
    }
         },
  {
    "operation": "remove",
    "spec": {
      "userName": ""
    }
  }
]

---

只需一次“移位”就可以做到这一点

规格

---

只需一次“移位”就可以做到这一点

规格