elasticsearch terms aggregation output keys

Question

Suppose I have a document like

doc :{
   item: {name: "Movie1", code: "M1"}
}

I can simply use terms aggregation on item.code and get all the buckets. But, is it possible to use aggregation on item.code but get the output bucket key to be the value of item.name

PS: I know I could use item.name in the terms aggregation, but due the nature of data (the names store vary slightly hence I have to use code), I need to bucket by code but output key as name .

Answer 1

Not exactly what you are looking for but it does what you need:

{
  "size": 0, 
  "aggs": {
    "whatever": {
      "terms": {
        "field": "item.code",
        "size": 10
      },
      "aggs": {
        "top1": {
          "top_hits": {
            "size": 1,
            "_source": {"exclude": "*"},
            "fields": ["item.name"]
          }
        }
      }
    }
  }
}