agg名称的排序未保留在响应中

如何解决agg名称的排序未保留在响应中

我正在执行弹性查询，并使用REST调用读取Java代码内部的响应。 当我读取响应时，未按响应顺序返回字段200、204、4xx，5xx的顺序。

在放置的示例请求下方找到

GET appl-activity*/_search
{
  "size": 0,"aggs": {
    "group_by_daterange": {
      "range": {
        "field": "Date","ranges": [
          {
            "from": "Fri Oct 23 02:54:26 2020 -0400","to": "Mon Oct 26 05:54:26 2020 -0400"
          }
        ]
      },"aggs": {
        "byapplication": {
          "terms": {
            "field": "application.keyword","size": 1000
          },"aggs": {
            "by200": {
              "sum": {
                "field": "200"
              }
            },"by204": {
              "sum": {
                "field": "204"
              }
            },"by4xx": {
              "sum": {
                "field": "4xx"
              }
            },"by5xx": {
              "sum": {
                "field": "5xx"
              }
            }
          }
        }
      }
    }
  }
}

响应返回：-

{
  "took" : 35,"timed_out" : false,"_shards" : {
    "total" : 2,"successful" : 2,"skipped" : 0,"failed" : 0
  },"hits" : {
    "total" : 1173,"max_score" : 0.0,"hits" : [ ]
  },"aggregations" : {
    "group_by_daterange" : {
      "buckets" : [
        {
          "key" : "Fri Oct 23 06:54:26 2020 +0000-Mon Oct 26 09:54:26 2020 +0000","from" : 1.603436066E12,"from_as_string" : "Fri Oct 23 06:54:26 2020 +0000","to" : 1.603706066E12,"to_as_string" : "Mon Oct 26 09:54:26 2020 +0000","doc_count" : 30,"byapplication" : {
            "doc_count_error_upper_bound" : 0,"sum_other_doc_count" : 0,"buckets" : [
              {
                "key" : "SITE","doc_count" : 20,"by4xx" : {
                  "value" : 1.0
                },"by5xx" : {
                  "value" : 0.0
                },"by204" : {
                  "value" : 0.0
                },"by200" : {
                  "value" : 5342.0
                }
              },{
                "key" : "MOBILE","doc_count" : 10,"by4xx" : {
                  "value" : 0.0
                },"by200" : {
                  "value" : 5635.0
                }
              }
            ]
          }
        }
      ]
    }
  }
}

我期望响应代码的顺序与请求中的顺序相同。请帮助我吗？

{
  "key": "MOBILE","doc_count": 10,"by200": {
    "value": 5635
  },"by204": {
    "value": 0
  },"by4xx": {
    "value": 0
  },"by5xx": {
    "value": 0
  }
}

解决方法

与数组不同，JSON字典不保证任何顺序。这意味着没有规范会强制ElasticSearch或任何其他JSON-in / JSON-out接口保留输入顺序。

不幸的是，某些系统（例如stripe）会花更多的精力在返回客户端之前按字母顺序对响应键进行排序。

---

话虽如此，我曾经通过根据想要的顺序在agg关键字名称前添加字母数字字符组合来解决此问题：

{
  "1__myAggName": { ... },"2__myAggName": { ... },...
}

然后在客户端上，我将对agg键进行简单排序并删除前缀。

但是这些天我倾向于在下订单和其他信息时使用aggregation metadata。这极大地提高了我所有后处理步骤的透明度和可读性：

{
  ...
  "byapplication": {
    "terms": {
      "field": "application.keyword","size": 1000
    },"aggs": {
      "by200": {
        "meta": {       <--
          "index": 0
        },"sum": {
          "field": "200"
        }
      },"by204": {
        "meta": {      <--
          "index": 1
        },"sum": {
          "field": "204"
        }
      },"by4xx": {
        "meta": {
          "index": 2
        },"sum": {
          "field": "4xx"
        }
      },"by5xx": {
        "meta": {
          "index": 3
        },"sum": {
          "field": "5xx"
        }
      }
    }
  }
}