ElasticSearch：列出给定术语查询的所有_source键

Question

我正在尝试在运行“条款”ElasticSearch查询（或任何其他查询）时获取_source字段中的所有子字段而不是文档。

假设我有类别的文档和许多其他数据，如颜色，大小，重量......这些字段是动态的，我不知道哪些字段会存在。

文件示例：

{
    "_index": "myindex",
    "_type": "document",
    "_id": "1",
    "_score": 1,
    "_source": {
        "entity_id": "1",
        "is_in_stock": "1",
        "weight": null,
        "color": null,
        "name": "My Document",
        "description": "Hello World",
        "categories": [
        "4185",
        "4626"
        ]
    }
}

某些文档有颜色，但不是全部，因此可以获取特定查询的所有非空字段，如下所示：

{
  "query": {
    "terms" : { "categories" : ["5581"] }
  }
}

预期结果会是这样的（假设提供的文档是我索引中唯一的文档）：

{
    "took": 42,
    "timed_out": false,
    "_shards": {
        "total": 5,
        "successful": 5,
        "skipped": 0,
        "failed": 0
    },
    "hits": {
        "total": 1,
        "max_score": 0,
        "hits": []
    },
    "aggregations": {
        "category_att": {
            "doc_count": 1,
            "cosmetique": {
                "doc_count_error_upper_bound": 0,
                "sum_other_doc_count": 0,
                "buckets": [
                    {
                        "key": "entity_id",
                        "doc_count": 1
                    },
                    {
                        "key": "is_in_stock",
                        "doc_count": 1
                    },
                    {
                        "key": "name",
                        "doc_count": 1
                    },
                    {
                        "key": "description",
                        "doc_count": 1
                    },
                    {
                        "key": "categories",
                        "doc_count": 1
                    }
                ]
            }
        }
    }
}

谢谢！