ElasticSearch - get all available filters (aggregate) from the index

Question

Let's say I have:

"hits": [
      {
        "_index": "products",
        "_type": "product",
        "_id": "599c2b3fc991ee0a597034fa",
        "_score": 1,
        "_source": {,
          "attributes": {
            "1": [
              "a"
            ],
            "2": [
              "b",
              "c"
            ],
            "3": [
              "d",
              "e"
            ],
            "4": [
              "f",
              "g"
            ],
            "5": [
              "h",
              "i"
            ]
          }
        }
      },
      {
        "_index": "products",
        "_type": "product",
        "_id": "599c4bb4b970c25976ced8bd",
        "_score": 1,
        "_source": {
          "attributes": {
            "1": [
              "z"
            ],
            "2": [
              "y"
            ]
          }
        }

Each product has attributes. Each attribute has an identifier and a value. I can filter products by attributes, but for now I am creating a list of "possible attributes" from MongoDB. I would like to find a way to create such a list only from ElasticSearch (and maybe just query MongoDB for more data).

What I need:

{
  1: [a, z],
  2: [b, c, y],
  etc.
}

What would such an aggregation look like? Get all the available attributes (grouped by attribute.id) with all their possible values ​​(for all products)?

Answer 1

You cannot do this in one query, but it is pretty easy in two:

Listing Attributes

, :

curl -XGET "http://localhost:9200/your_index/your_type/_mapping"

, :

curl -XGET "http://localhost:9200/your_index/your_type/_search" -H 'Content-Type: application/json' -d'
{
  "size": 0,
  "aggs": {
    "field1Values": {
      "terms": {
        "field": "field1",
        "size": 20
      }
    },
    "field2Values": {
      "terms": {
        "field": "field2",
        "size": 20
      }
    },
    "field3Values": {
      "terms": {
        "field": "field3",
        "size": 20
      }
    },
    ...
  }
}'

20 .

20 (, ). "size" , . , , - 10 , , , .

, , , . , , , cardinality * 2.

curl -XGET "http://localhost:9200/your_index/your_type/_search" -H 'Content-Type: application/json' -d'
{
  "size": 0,
  "aggs": {
    "field1Cardinality": {
      "cardinality": {
        "field": "field1"
      }
    },
    "field2Cardinality": {
      "cardinality": {
        "field": "field2"
      }
    },
    "field3Cardinality": {
      "cardinality": {
        "field": "field3"
      }
    },
    ...
  }
}'

, . , , , ,

:

{
    "attributes":[
        {
            "name":"1",
            "value":[
                "a"
            ]
        },
        {
            "name":"2",
            "value":[
                "b",
                "c"
            ]
        },
        {
            "name":"3",
            "value":[
                "d",
                "e"
            ]
        },
        {
            "name":"4",
            "value":[
                "f",
                "g"
            ]
        },
        {
            "name":"5",
            "value":[
                "h",
                "i"
            ]
        }
    ]
}

, "" "", "", , :

curl -XGET "http://localhost:9200/your_index/your_type/_search" -H 'Content-Type: application/json' -d'
{
  "size": 0,
  "aggs": {
    "attributes": {
      "terms": {
        "field": "attributes.name",
        "size": 1000
      },
      "aggs": {
        "values": {
          "terms": {
            "field": "attributes.value",
            "size": 100
          }
        }
      }
    }
  }
}'

.