elasticsearch calculate average of unique values

Question

How can I dynamically calculate the average of unique values in elasticsearch?

{ "price" : 10000, "color" : "red" }
{ "price" : 20000, "color" : "red" }
{ "price" : 30000, "color" : "green" }
{ "price" : 15000, "color" : "blue" }
{ "price" : 12000, "color" : "green" }
{ "price" : 20000, "color" : "red" }
{ "price" : 80000, "color" : "red" }
{ "price" : 25000, "color" : "blue" }

In the above data, how can I get the unique values of the "color" field and then the averages for each of the unique "color" fields?

Answer 1

Using a terms aggregation to figure out the unique color values and then an avg sub-aggregation would do the trick:

{
  "aggs": {
    "colors": {
      "terms": {
        "field": "color"
      },
      "aggs": {
        "average": {
          "avg": {
            "field": "price"
          }
        }
      }
    }
  }
}