请求编写Apache NiFi的Jolt规范，实现指定JSON格式转换

输入JSON #

{"eventid": "165","name": "High memory utilization","severity": "0","userid": "1","hosts": [{"hostid": "101","proxy_hostid": "0","host": "hostname","name": "name"}],"relatedObject": {"description": "High memory utilization","comments": "The system is running out of free memory.","uuid": ""},"tags": [{"tag": "component","value": "memory"},{"tag": "class","value": "os"},{"tag": "target","value": "linux"}]}

预期输出JSON #

{"severity" : "0","name" : "High memory utilization","host" : "hostname","parameter" : "memory"}

Jolt转换规范（Shift操作） #

[
  {
    "operation": "shift",
    "spec": {
      "severity": "severity",
      "name": "name",
      "hosts": {
        "0": {
          "host": "host"
        }
      },
      "tags": {
        "*": {
          "tag": {
            "component": {
              "@(2,value)": "parameter"
            }
          }
        }
      }
    }
  }
]

规范说明 #

• 直接映射severity和name字段到输出对应键；
• 从hosts数组的第一个元素（索引0）中提取host字段；
• 遍历tags数组，匹配tag值为component的项，通过@(2,value)向上两层获取该项的value值，映射到输出的parameter字段。

内容的提问来源于stack exchange，提问作者Sathish