无法基于弹性搜索中的多个文本字段进行排序

Question

doc1: 
{
    "createdAt": "2022-11-25T09:45:00.000Z",
    "tags": [
      "Response Needed"
    ]
}
doc2 :
{
    "createdAt": "2022-11-24T09:45:00.000Z",
    "tags": [
      "Customer care","Response Needed"
    ]
}
doc3 :
{
    "createdAt": "2022-11-24T09:45:00.000Z",
    "tags": [
     
    ]
}

I want to sort the below documents based on tags first and then createdAt. If tags is present then it should be in ascending order of createdAt otherwise if tags is blank then it should be in sort based on createdAt in Descending order.

Answer 1

I believe the solution is to use Script based sorting .

PUT idx_sort
{
  "mappings": {
      "properties": {
        "createdAt": {
          "type": "date"
        },
        "tags": {
          "type": "keyword"
        }
      }
    }
}

POST idx_sort/_doc
{
    "createdAt": "2022-11-25T09:45:00.000Z",
    "tags": [
      "Response Needed"
    ]
}

POST idx_sort/_doc
{
    "createdAt": "2022-11-24T09:45:00.000Z",
    "tags": [
      "Response 02"
    ]
}

POST idx_sort/_doc
{
    "createdAt": "2022-11-24T09:45:00.000Z",
    "tags": [
      "Customer care","Response Needed"
    ]
}

POST idx_sort/_doc
{
    "createdAt": "2022-11-24T09:45:00.000Z",
    "tags": [
     
    ]
}

Query

GET idx_sort/_search
{
  "sort": [
    {
      "_script": {
        "type": "number",
        "script": {
          "lang": "painless",
          "source": """
          def list = doc['tags.keyword'];
          if(list.size() > 0){
            return list.size();
          } else {
            return 0;
          }
          """
        },
        "order": "desc"
      }
    },
    {
      "createdAt": {
        "order": "asc"
      }
    }
  ]
}

Response

"hits": [
      {
        "_index": "idx_sort",
        "_id": "j489toQBEoAIompjkkXO",
        "_score": null,
        "_source": {
          "createdAt": "2022-11-24T09:45:00.000Z",
          "tags": [
            "Response 02"
          ]
        },
        "sort": [
          1,
          1669283100000
        ]
      },
      {
        "_index": "idx_sort",
        "_id": "kI89toQBEoAIompjxkWN",
        "_score": null,
        "_source": {
          "createdAt": "2022-11-24T09:45:00.000Z",
          "tags": [
            "Customer care",
            "Response Needed"
          ]
        },
        "sort": [
          1,
          1669283100000
        ]
      },
      {
        "_index": "idx_sort",
        "_id": "jo83toQBEoAIompjcEXD",
        "_score": null,
        "_source": {
          "createdAt": "2022-11-25T09:45:00.000Z",
          "tags": [
            "Response Needed"
          ]
        },
        "sort": [
          1,
          1669369500000
        ]
      },
      {
        "_index": "idx_sort",
        "_id": "kY8-toQBEoAIompj6kXg",
        "_score": null,
        "_source": {
          "createdAt": "2022-11-24T09:45:00.000Z",
          "tags": []
        },
        "sort": [
          0,
          1669283100000
        ]
      }
    ]