ElasticSearch - 对桶进行排序

Question

我的 elasticSearch 查询 是这样的：

{
    "size": 0,
    "aggs": {
        "group_by_name": {
            "terms": {
                "field": "Infos.InstanceInfo.Name.keyword",
                "size": 1000
            },
            "aggs": {
                "group_by_id": {
                    "terms": {
                        "field": "Infos.InstanceInfo.ID.keyword",
                        "size": 1000
                    },
                    "aggs": {
                        "tops": {
                            "top_hits": {
                                "size": 100,
                                "sort": {
                                    "Infos.InstanceInfo.StartTime": "asc"
                                }
                            }
                        }
                    }
                },
                "count": {
                    "cardinality": {
                        "field": "Infos.InstanceInfo.ID.keyword"
                    }
                }
            }
        }
    }
}

效果很好，我有一个这种形式的结果：

aggregations
==>group_by_name
======>buckets:
        {key:name1}
        =========>group_by_id
        ==============>buckets
                        {key:id1}
                        ===============>docs
                        {doc1.StartTime:"2020-12-15T19:00:00"}
                        {doc2.StartTime:"2020-12-15T20:00:00"}
                        {doc3.StartTime:"2020-12-15T21:00:00"}
                        
                        {key:id2}
                        ===============>docs
                        {doc1.StartTime:"2020-12-15T09:00:00"}
                        {doc2.StartTime:"2020-12-15T11:00:00"}
                        {doc3.StartTime:"2020-12-15T11:30:00"}
                        
                        {key:id4}
                        ===============>docs
                        {doc1.StartTime:"2020-12-15T22:00:00"}
                        {doc2.StartTime:"2020-12-15T23:00:00"}
                        {doc3.StartTime:"2020-12-15T23:30:00"}

        {key:name2}
        =========>group_by_id
        ==============>buckets
                        {key:id5}
                        ===============>docs
                        {doc1.StartTime:"2020-12-15T05:00:00"}
                        {doc2.StartTime:"2020-12-15T05:30:00"}
                        {doc3.StartTime:"2020-12-15T06:00:00"}
                        
                        {key:id8}
                        ===============>docs
                        {doc1.StartTime:"2020-12-15T01:00:00"}
                        {doc2.StartTime:"2020-12-15T01:00:15"}
                        {doc3.StartTime:"2020-12-15T02:00:00"}
                        
                        {key:id9}
                        ===============>docs
                        {doc1.StartTime:"2020-12-15T08:00:00"}
                        {doc2.StartTime:"2020-12-15T09:00:15"}
                        {doc3.StartTime:"2020-12-15T10:00:00"}

现在，我正在尝试根据第一个文档的 StartTime 的值对 group_by_id 聚合中的存储桶进行排序，以获得如下结果：

aggregations
==>group_by_name
======>buckets:
        {key:name1}
        =========>group_by_id
        ==============>buckets
                        {key:id4}
                        ===============>docs
                        {doc1.StartTime:"2020-12-15T22:00:00"}
                        {doc2.StartTime:"2020-12-15T23:00:00"}
                        {doc3.StartTime:"2020-12-15T23:30:00"}
                        
                        {key:id1}
                        ===============>docs
                        {doc1.StartTime:"2020-12-15T19:00:00"}
                        {doc2.StartTime:"2020-12-15T20:00:00"}
                        {doc3.StartTime:"2020-12-15T21:00:00"}
                        
                        {key:id2}
                        ===============>docs
                        {doc1.StartTime:"2020-12-15T09:00:00"}
                        {doc2.StartTime:"2020-12-15T11:00:00"}
                        {doc3.StartTime:"2020-12-15T11:30:00"}

        {key:name2}
        =========>group_by_id
        ==============>buckets
                        {key:id9}
                        ===============>docs
                        {doc1.StartTime:"2020-12-15T08:00:00"}
                        {doc2.StartTime:"2020-12-15T09:00:15"}
                        {doc3.StartTime:"2020-12-15T10:00:00"}
                        
                        {key:id5}
                        ===============>docs
                        {doc1.StartTime:"2020-12-15T05:00:00"}
                        {doc2.StartTime:"2020-12-15T05:30:00"}
                        {doc3.StartTime:"2020-12-15T06:00:00"}
                        
                        {key:id8}
                        ===============>docs
                        {doc1.StartTime:"2020-12-15T01:00:00"}
                        {doc2.StartTime:"2020-12-15T01:00:15"}
                        {doc3.StartTime:"2020-12-15T02:00:00"}

有什么想法吗？

Answer 1

执行以下操作：

{
  "size": 0,
  "aggs": {
    "group_by_name": {
      "terms": {
        "field": "Infos.InstanceInfo.Name.keyword",
        "size": 1000,
        "order": {                                         <-- name1, name2, ... alphabetically
          "_key": "asc"
        }
      },
      "aggs": {
        "group_by_id": {
          "terms": {
            "field": "Infos.InstanceInfo.ID.keyword",
            "size": 1000,
            "order": {                                     <-- order by the latest timestamp 
              "max_start_time": "desc"
            }
          },
          "aggs": {
            "tops": {
              "top_hits": {
                "size": 100,
                "_source": "Infos.InstanceInfo.StartTime",
                "sort": {
                  "Infos.InstanceInfo.StartTime": "asc"
                }
              }
            },
            "max_start_time": {                           <-- specify it here in order to apply it above
              "max": {
                "field": "Infos.InstanceInfo.StartTime"
              }
            }
          }
        },
        "count": {
          "cardinality": {
            "field": "Infos.InstanceInfo.ID.keyword"
          }
        }
      }
    }
  }
}