ElasticSearch Filtering aggregations from array field

Question

I am trying to do an aggregation on values in an array and also filter the buckets that are returned by a prefix. Not sure if this is possible or I am misusing the filter b

Answer 1

Try this, it will filter the values the buckets themselves are created for:

{
  "size": 0,
  "aggs": {
    "colors": {
      "filter": {
        "prefix": {
          "colors": "b"
        }
      },
      "aggs": {
        "top-colors": {
          "terms": {
            "field": "colors",
            "include": {
              "pattern": "b.*"
            }
          }
        }
      }
    }
  }
}